JP2009068826A - Method and apparatus for producing clathrate hydrate slurry and method of operating the production apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique by which a clathrate hydrate slurry can be stably produced over a long period of time while maintaining a merit in which a clathrate hydrate adherent to a heat exchange surface of a heat exchanger has the effect of accelerating the fresh formation of a clathrate hydrate. <P>SOLUTION: A method for producing the clathrate hydrate slurry has a step in which either an aqueous solution of a guest compound for a clathrate hydrate or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water is made to flow in a heat exchanger tube to yield the clathrate hydrate in the aqueous solution or the slurry through heat exchange with a refrigerant surrounding the outer periphery of the heat exchanger tube. The amount of the clathrate hydrate adhering to the inner wall surface of the heat exchanger tube in the course of heat exchange with the refrigerant is inhibited from increasing by the force of flow of the aqueous solution or slurry running in the heat exchanger tube. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a clathrate hydrate slurry production technique using a heat transfer tube as a heat exchanger, and more specifically, an aqueous solution of clathrate hydrate guest compound or clathrate hydrate is dispersed in an aqueous solution or water. Inclusion hydration comprising a step of flowing a slurry in suspension into a heat transfer tube and generating clathrate hydrate in the aqueous solution or slurry through heat exchange with a refrigerant around the heat transfer tube The present invention relates to a method for manufacturing a product slurry, an apparatus for realizing the manufacturing method, and a method for operating the apparatus.

In the present invention, the following terms are defined or interpreted as follows.
(1) “Clusion clathrate hydrate” includes quasi clathrate hydrate. Hereinafter, it may be simply abbreviated as “hydrate”.
(2) “Clusion clathrate hydrate slurry” or “hydrate slurry” refers to a slurry-like substance formed by dispersing or suspending clathrate hydrate in an aqueous solution or aqueous solvent of the guest compound. Even if another composition (including additives) is present in the aqueous solution or water solvent, as long as the clathrate hydrate is dispersed or suspended, the “clathrate hydrate slurry” or “hydration” Corresponding to “product slurry”.
(3) “Aqueous solution of clathrate hydrate guest compound” refers to an aqueous solution containing a guest compound of clathrate hydrate as a solute, and clathrate hydrate or another composition ( Even if an additive is present, the solution falls under the “aqueous solution of a clathrate hydrate guest compound” as long as the clathrate hydrate guest compound is an aqueous solution.
(4) “Raw material solution” refers to an aqueous solution of a clathrate hydrate guest compound that has the property of forming clathrate hydrate upon cooling.
(5) “Raw material slurry” refers to a clathrate hydrate slurry or a hydrate slurry having the property of generating clathrate hydrate when cooled.
(6) “Refrigerant” and “heat medium” are different in terms and terms, and have different uses such as hydrate generation and condensation, but both store and transport thermal energy. Means a substance that can.

  For example, in the field of heat utilization, a clathrate hydrate slurry used as a heat medium such as a heat storage medium or a latent heat transport medium can be produced by cooling a raw material solution or a raw material slurry through heat exchange with a refrigerant. Yes (Patent Document 1). An example of a heat exchanger that enables the heat exchange is to use a heat transfer tube, which can be further subdivided into a single tube type and a multi-tube type (including a shell and tube type), and A heat exchange is performed by placing a refrigerant around the outer periphery of the heat tube and a raw material solution or slurry inside the heat pipe, and conversely, a refrigerant inside the heat transfer tube and a raw material solution or raw material slurry around the outer periphery, respectively. By arranging, it can be divided into those that perform heat exchange (see Patent Documents 2 and 3).

By the way, it is known that the clathrate hydrate adhering to the heat exchange surface of the heat exchanger has the effect of promoting the production of new clathrate hydrate as a production nucleus (Patent Document) 4 and 5).
On the other hand, if the clathrate hydrate adheres to the heat exchange surface of the heat exchanger, the heat exchange surface is not exposed and hinders heat exchange. In particular, when using a heat exchanger configured to perform heat exchange by disposing a refrigerant around the outer periphery of the heat transfer tube and a raw material solution or raw material slurry inside the heat transfer tube, the heat transfer tube adheres to and accumulates on the inner wall surface of the heat transfer tube. The clathrate hydrate prevents the flow of the raw material solution or the raw material slurry. As a result, the clathrate hydrate slurry cannot be stably produced for a long time. For this reason, by increasing the flow rate of the raw material solution or raw material slurry, the attached clathrate hydrate is forcibly separated from the heat exchange surface, and appropriate parameters are detected to determine whether the separation has been performed completely. (Patent Document 6).
JP 2004-93052 A JP 2002-263470 A JP 2004-85008 A JP 2000-234769 A JP 2002-283223 A Japanese Patent No. 2001-343139

  However, if the clathrate hydrate adhering to the heat exchange surface of the heat exchanger is completely peeled off, the clathrate hydrate slurry can be stably produced. There is no denying the fact that the production of new clathrate hydrate is promoted because the clathrate hydrate adhering to the heat exchange surface serves as a nucleus of formation because the emphasis is placed on the production of the product.

  The present invention has been made in view of the above circumstances, while maintaining the advantage of the effect of promoting the generation of a new clathrate hydrate by the clathrate hydrate attached to the heat exchange surface of the heat exchanger, It aims at providing the technique which can manufacture a clathrate hydrate slurry stably over a long time.

  In order to achieve the above object, a method for producing an clathrate hydrate according to the first aspect of the present invention comprises an aqueous solution of a guest compound of clathrate hydrate or the clathrate hydrate in the aqueous solution or water. Flowing the slurry dispersed or suspended inside the heat transfer tube, and generating the clathrate hydrate in the aqueous solution or the slurry through heat exchange with the refrigerant around the heat transfer tube. A method for producing a clathrate hydrate slurry, wherein an increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant flows through the heat transfer tube. It is suppressed by the flow force of the aqueous solution or the slurry.

  The method for producing clathrate hydrate according to the second aspect of the present invention includes an aqueous solution of a clathrate hydrate guest compound or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water. The clathrate hydrate slurry is produced by flowing the heat flux into the inside of the heat transfer tube and generating the clathrate hydrate in the aqueous solution or the slurry through heat exchange with a refrigerant around the heat transfer tube. In this method, part of the clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant is removed by the flow force of the aqueous solution or slurry, and the rest is transferred to the heat transfer tube. The heat pipe is left so as to cover the inner wall surface.

  The clathrate hydrate slurry production method according to the third aspect of the present invention is the production method according to the first or second aspect, wherein the aqueous solution or a part of the slurry that has passed through the heat transfer tube or The whole is refluxed to the heat transfer tube.

  The manufacturing method of the clathrate hydrate slurry which concerns on the 4th form of this invention is a manufacturing method which concerns on any 1st thru | or 3rd form, Comprising: It has the process of adjusting the temperature of the said refrigerant | coolant. It is a feature.

  The clathrate hydrate slurry manufacturing method according to the fifth aspect of the present invention is the clathrate hydrate slurry manufacturing method according to the fourth aspect, wherein the temperature of the refrigerant is the clathrate hydrate. The temperature is adjusted to a temperature close to the freezing point and close to the freezing point or the temperature of the aqueous solution or slurry flowing inside the heat transfer tube.

  The clathrate hydrate manufacturing apparatus according to the sixth aspect of the present invention includes a plurality of heat transfer tubes, a refrigerant supply device that supplies a refrigerant to the outer periphery of each heat transfer tube, and a clathrate water inside each heat transfer tube. A stock solution supply device for supplying a slurry obtained by dispersing or suspending an aqueous solution of a guest compound of the Japanese or the clathrate hydrate in the aqueous solution or water, and a flow rate setting device for setting a flow rate of the aqueous solution or the slurry. A clathrate hydrate slurry producing apparatus in which the clathrate hydrate is generated in the aqueous solution or the slurry through heat exchange with the refrigerant. The flow rate of the aqueous solution or the slurry is set so that an increase in the amount of the clathrate hydrate adhering to the wall surface is suppressed by the flow force of the aqueous solution or the slurry flowing inside each heat transfer tube. It is characterized by That.

  The clathrate hydrate manufacturing apparatus according to the seventh aspect of the present invention includes a plurality of heat transfer tubes, a refrigerant supply device that supplies a refrigerant to the outer periphery of each heat transfer tube, and a clathrate water inside each heat transfer tube. A stock solution supply device for supplying a slurry obtained by dispersing or suspending an aqueous solution of a guest compound of the Japanese or the clathrate hydrate in the aqueous solution or water, and a flow rate setting device for setting a flow rate of the aqueous solution or the slurry. A clathrate hydrate slurry producing apparatus in which the clathrate hydrate is generated in the aqueous solution or the slurry through heat exchange with the refrigerant. The flow rate of the aqueous solution or slurry is such that a part of the clathrate hydrate adhering to the wall surface is removed by the flow force of the aqueous solution or slurry, and the remainder remains so as to cover the inner wall surface of each heat transfer tube. Features that are set It is intended to.

  The clathrate hydrate slurry production apparatus according to the eighth aspect of the present invention is the production apparatus according to the sixth or seventh aspect, wherein the aqueous solution or slurry supplied to the inside of each heat transfer tube It is characterized by comprising turbulence forming means for forming turbulence in the flow.

  The clathrate hydrate slurry production apparatus according to the ninth aspect of the present invention is the production apparatus according to any one of the sixth to eighth aspects, wherein at least one of the inner wall surface and the outer wall surface of each heat transfer tube. In addition, unevenness is formed along the direction in which the aqueous solution or the slurry flows.

  A clathrate hydrate slurry production apparatus according to a tenth aspect of the present invention is the production apparatus according to any one of the sixth to ninth aspects, wherein the aqueous solution or one of the slurries that has passed through the heat transfer tube. A part or the whole is provided with a circulation device that circulates back to the heat transfer tube.

  The clathrate hydrate slurry production apparatus according to the eleventh aspect of the present invention is the production apparatus according to any one of the sixth to tenth aspects, wherein the refrigerant temperature adjustment apparatus for adjusting the temperature of the refrigerant is provided. It is characterized by comprising.

  The operation method of the clathrate hydrate slurry manufacturing apparatus according to the twelfth aspect of the present invention includes a plurality of heat transfer tubes, a refrigerant supply device that supplies refrigerant to the outer periphery of each heat transfer tube, and the inside of each heat transfer tube An aqueous solution of a clathrate hydrate guest compound or a stock solution supply device for supplying a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water, and setting the flow rate of the aqueous solution or the slurry. A flow rate setting device, and a circulation device that recirculates a part or all of the aqueous solution or the slurry that has passed through each heat transfer tube to the heat transfer tube at all times or as needed, through the heat exchange with the refrigerant, the aqueous solution or the The clathrate hydrate slurry manufacturing apparatus operating method in which the clathrate hydrate is generated in the slurry, each time during the initial operation of the manufacturing apparatus, at the restart operation after the stop or at the performance confirmation operation, Inner wall of heat transfer tube As well as eliminating the force flow of the aqueous solution or the slurry a portion of the clathrate hydrate deposited on, is characterized in that leaves the remainder so as to cover the inner wall surface of each heat transfer tube.

  The operating method of the clathrate hydrate slurry manufacturing apparatus according to the thirteenth aspect of the present invention includes a plurality of heat transfer tubes, a refrigerant supply device that supplies a refrigerant to the outer periphery of each heat transfer tube, and the temperature of the refrigerant. A refrigerant temperature adjusting device to be adjusted, and a raw solution supply for supplying an aqueous solution of a clathrate hydrate guest compound or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water inside each heat transfer tube A flow rate setting device for setting the flow rate of the aqueous solution or the slurry, and a circulation device for returning a part or all of the aqueous solution or the slurry that has passed through each heat transfer tube to the heat transfer tube at all times or as necessary. Comprising a clathrate hydrate slurry manufacturing apparatus in which the clathrate hydrate is generated in the aqueous solution or the slurry through heat exchange with the refrigerant, the initial time of the manufacturing apparatus, Re-after pause During operation or performance check operation, the temperature of the refrigerant is set to a temperature higher than the freezing point of the clathrate hydrate by the refrigerant temperature adjusting device, and the clathrate hydrate adhered to the inner wall surface of each heat transfer tube A part is removed by the flow force of the aqueous solution or the slurry, and the remaining part is left so as to cover the inner wall surface of each heat transfer tube.

The operation method of the clathrate hydrate slurry manufacturing apparatus according to the fourteenth aspect of the present invention includes a plurality of heat transfer tubes, a refrigerant supply device that supplies a refrigerant to the outer periphery of each heat transfer tube, and the temperature of the refrigerant. A refrigerant temperature adjusting device to be adjusted, and a raw solution supply for supplying an aqueous solution of a clathrate hydrate guest compound or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water inside each heat transfer tube A flow rate setting device for setting a flow rate of the aqueous solution or the slurry, and a circulation device for returning a part or all of the aqueous solution or the slurry that has passed through each heat transfer tube to the heat transfer tube at all times or as necessary. Comprising the clathrate hydrate slurry manufacturing apparatus in which the clathrate hydrate is produced in the aqueous solution or the slurry through heat exchange with the refrigerant,
During normal operation of the manufacturing apparatus, the refrigerant temperature adjustment device suppresses fluctuations in the temperature of the refrigerant, and a part of the clathrate hydrate adhering to the inner wall surface of each heat transfer tube is removed from the flow of the aqueous solution or slurry. While removing by force, the remainder is left so that the inner wall surface of each heat exchanger tube may be covered.

The principle of the present invention will be described.
1 to 3 are conceptual explanatory diagrams of the state of formation of clathrate hydrate, and more specifically, an aqueous solution (raw material solution) of a guest compound of clathrate hydrate or the clathrate hydrate as the aqueous solution or water. The slurry (raw material slurry) dispersed or suspended in is flown into the heat transfer tube, and the clathrate hydrate is generated in the raw material solution or raw material slurry through heat exchange with the refrigerant around the heat transfer tube. This is a conceptual view of the situation of making a clathrate hydrate slurry.

  The above raw material solution or raw material slurry is flowed into the heat transfer tube, and the refrigerant temperature is set so that the temperature of the inner wall surface of the heat transfer tube is equal to or lower than the freezing point (or generation start temperature) of the clathrate hydrate. Then, a hydrate is formed at the interface between the inner wall surface and the raw material solution or slurry, or in the raw material solution near the inner wall surface, and adheres or accumulates on the inner wall surface (see FIG. 1). The effect of cooling by the refrigerant through the heat transfer tube extends to the raw material solution through the hydrate attached or deposited on the inner wall surface of the heat transfer tube, so that columnar and needle-like hydrate crystals are formed on the hydrate surface. The thickness of the clathrate hydrate deposited or deposited (the thickness from the inner surface of the heat transfer tube toward the center of the tube; the same shall apply hereinafter) increases (see FIG. 2).

  Among the hydrates adhering to the inner wall surface of the heat transfer tube, those exposed to the raw material solution or raw material slurry become the core of hydrate formation, which increases the adhesion thickness or deposition thickness of clathrate hydrates. Spur. As a result, the thickness of the hydrate layer attached to the inner wall surface gradually increases.

  On the other hand, as the thickness of the clathrate hydrate deposited or deposited increases, the flow rate of the raw material solution or raw material slurry flowing in the heat transfer tube gradually decreases as the flow path cross-sectional area in the heat transfer tube decreases (see FIG. 2). The flow force (for example, shearing force) of the raw material solution or the raw material slurry gradually increases. Here, of the clathrate hydrate adhering to and depositing on the inner wall surface of the heat transfer tube, the portion on the side of the raw material solution or raw material slurry or the inner surface of the heat transfer tube toward the center of the tube (ie, the raw material solution or raw material slurry The exposed part) is quite soft and relatively easy to peel off. The degree of softness and ease of peeling vary depending on various conditions (for example, the temperature difference between the raw material solution or raw material slurry and the refrigerant), but are clearly softer than ice. Therefore, hydration from the softer portion of the hydrate layer adhering to the inner wall surface of the heat transfer tube due to the flow force of the raw material solution or raw material slurry, that is, the portion exposed to the raw material solution or raw material slurry side. Although the physical crystals are peeled off, the thickness of the hydrate layer attached to the inner wall surface gradually increases (see FIG. 3).

  Finally, the amount of hydrate particles adhering or depositing on the inner wall surface of the heat transfer tube is balanced with the amount of hydrate particles adhering or accumulating on the inner wall of the heat transfer tube. However, the variation in the adhesion thickness or the deposition thickness on the inner wall surface of the heat transfer tube is eliminated or the variation becomes very small.

At this time, the hydrate crystals separated from the hydrate layer attached or deposited on the inner wall surface of the heat transfer tube are usually fine particles of about 50 to 100 microns, and function as nuclei of new hydrates. Therefore, the supercooled state of the raw material solution or raw material slurry is released. In addition, the hydrate crystals are dispersed or suspended in the raw material solution or the raw material slurry, and become the clathrate hydrate slurry as a whole.
In addition, when the adhesion thickness or deposition thickness of the hydrate on the inner wall surface of the heat transfer tube increases to a certain level or more, the cooling effect by the refrigerant through the heat transfer tube does not reach the raw material solution or the raw material slurry, and the increase will eventually reach its peak. Become. However, due to the above-described peeling effect of the hydrate due to the flow force of the raw material solution or raw material slurry, the adhesion thickness or deposition thickness is suppressed to a range in which the cooling effect reaches the raw material solution or raw material slurry by the refrigerant. Formation and exfoliation of hydrate crystals occur continuously. Then, the new hydrate crystals are dispersed or suspended in the raw material solution or the raw slurry, and become the clathrate hydrate slurry as a whole.

  In the present invention, based on the principle of the present invention described above, the raw material solution or raw material slurry of clathrate hydrate is caused to flow inside the heat transfer tube, and the raw material solution or the raw material slurry is exchanged with the refrigerant around the heat transfer tube. When generating clathrate hydrate, the increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube is suppressed by the flow force of the raw material solution or raw material slurry flowing inside the heat transfer tube. . More specifically, a part of clathrate hydrate adhering to the inner wall surface of the heat transfer tube (a soft and easily peelable portion on the side of the raw material solution or raw slurry or the side of the heat transfer tube in the tube center direction). The raw material solution or the raw material slurry is peeled or scraped off by the shearing force or other force of the raw material solution or the raw material slurry and removed together with the flow, and the remaining part is dared to cover the inner wall surface of the heat transfer tube.

Thus, according to the present invention, the following operational effects can be obtained.
(A) Since the adhesion thickness or deposition thickness of clathrate hydrate remaining on the inner wall surface of the heat transfer tube does not exceed the level determined by the balance with the strength of the flow of the raw material solution or raw material slurry (becomes peak), The cooling effect by the exchanger can be maintained to such an extent that clathrate hydrate is generated from the raw material solution or raw material slurry.
(B) The clathrate hydrate removed by the flow force of the raw material solution or raw material slurry is dispersed or suspended in the raw material solution or raw material slurry. Therefore, it is possible to produce an clathrate hydrate slurry having a higher clathrate hydrate content ratio or solid phase fraction than the original raw material solution or raw slurry.
(C) Since the clathrate hydrate remaining on the inner wall surface of the heat transfer tube functions as a production nucleus, a new clathrate hydrate can be easily generated.

(D) In the case where the raw slurry is caused to flow inside the heat transfer tube, the clathrate hydrate present in the original raw slurry functions as a production nucleus, so that a new clathrate hydrate can be easily generated. Can do.
(E) The clathrate hydrate removed from the heat transfer tube is dispersed or suspended in the subcooled raw material solution or raw slurry in the process of passing through the heat transfer tube, thereby forming a new nucleus of clathrate hydrate Thus, since it functions as a supercooling release agent, even after passing through the heat transfer tube, it is possible to promote the increase in the inclusion ratio or solid phase fraction of the clathrate hydrate in the clathrate hydrate slurry.
Thus, the clathrate hydrate slurry can be stably produced over a long period of time or continuously.

In addition, as the above explanation suggests, when adjusting or controlling the performance or capacity of the clathrate hydrate slurry production apparatus or clathrate hydrate slurry production capacity, it remains on the inner wall surface of the heat transfer tube. It is important to adjust or control the clathrate hydrate deposition or deposition thickness.
The adhesion thickness or deposition thickness can be adjusted or controlled by the flow force of the raw material solution or raw material slurry or a parameter correlated with this force. Typical examples of such parameters are the flow rate (ie, the value obtained by dividing the flow rate of the raw material solution or raw material slurry per unit time by the inner cross-sectional area of the heat transfer tube), the material and dimensions of the heat transfer tube, and the exchange in the heat exchanger. Calorific value, concentration of raw material solution, freezing point (generation start temperature), viscosity and temperature of raw material solution and raw material slurry, pressure loss before and after raw material solution or raw material slurry passes through heat transfer tube, temperature of refrigerant around outer periphery of heat transfer tube And how to sink.

  However, among the above parameters, there are parameters that are already determined at the time of starting the production of clathrate hydrate slurry (for example, dimensions and materials of heat transfer tubes) and parameters that are not. When aiming to produce clathrate hydrate slurry stably over a long period of time, adjust or control with parameters that are easy to adjust or control during operation of clathrate hydrate slurry production equipment Is preferred. The flow rate is optimal as such a parameter. Even if parameters other than the flow rate fluctuate during the production of the clathrate hydrate slurry, if the flow rate is adjusted or controlled in accordance with the fluctuation, the adhesion thickness of the clathrate hydrate remaining on the inner wall surface of the heat transfer tube or This is because it is often possible to adjust or control the deposition thickness, that is, the performance and capacity of the clathrate hydrate slurry production apparatus or the clathrate hydrate slurry production capacity.

  In order to adjust or control the amount of clathrate hydrate produced and the amount attached to the inner wall surface of the heat transfer tube, at least one of the temperature of the refrigerant and the temperature of the raw material solution or raw material slurry is selected as a parameter. It is also effective to adjust or control this. In this case, adjusting or controlling the temperature of the refrigerant is more responsive to the amount of clathrate hydrate produced or attached to the inner wall surface of the heat transfer tube than to adjust or control the temperature of the raw material solution or raw material slurry. It is preferable in that it has a high immediate effect and can avoid the complexity of the actual device.

The range in which the clathrate hydrate covers the inner wall surface in the tube axis direction of the heat transfer tube may be the whole range or a part of the range, but the stability of clathrate hydrate slurry production From the viewpoint, it is preferable that the clathrate hydrate adhered to the inner wall surface is uniform.
As a matter of fact, when the clathrate hydrate is thickly deposited on a wide area of the inner wall surface of the heat transfer tube, the pressure loss of the raw material solution or raw material slurry flowing therethrough becomes high, The power of the pump will also increase, and eventually the cost of equipment and facilities may increase. With these economic aspects in mind, if the above parameters are varied so as to be suitable for long-term stable production of clathrate hydrate slurries, the allowable variation range of the above parameters can be empirically or reasonably estimated. Can be evaluated. In the course of the determination operation or as a result, the thickness of the clathrate hydrate deposited or deposited on the inner wall surface of the heat transfer tube and the preferred range of the extent of the coverage are determined empirically or with reasonable assumptions.

Hereinafter, the effect which each form of the present invention shows is explained.
According to the first aspect of the present invention, the increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant is caused by the increase in the amount of the raw material solution or the raw material slurry flowing inside the heat transfer tube. Since it is suppressed by the force of the flow, the effects (a) to (e) above, and the effect that the clathrate hydrate slurry can be stably produced over a long period of time or continuously. Play.

According to the second aspect of the present invention, part of the clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant is removed by the flow force of the raw material solution or raw material slurry, Since the remaining part is left so as to cover the inner wall surface of the heat transfer tube, the effects (a) to (e) described above, and thus the clathrate hydrate slurry can be stably produced over a long period of time or continuously. There is an effect that it can be performed.
In the second embodiment of the present invention, clathrate hydrate formation nuclei are widely distributed on the inner wall surface of the heat transfer tube, and the inside of the heat transfer tube is easy to produce clathrate hydrate. Therefore, the effect (c) is remarkably exhibited.

According to the third aspect of the present invention, the above effects (a) to (e), and further, the clathrate hydrate slurry can be stably produced over a long period of time or continuously. In addition to the effects described above, the following effects (f) and (g) are exhibited.
(F) Since part or all of the aqueous solution or slurry that has passed through the heat transfer tube flows again to the heat transfer tube as a raw material solution or raw material slurry, the inclusion ratio or solid phase content of the clathrate hydrate in the clathrate hydrate slurry The rate can be increased with each reflux.
(G) The clathrate hydrate is attached to the inner wall surface of the heat transfer tube, to which the clathrate hydrate has been attached at all or only in a small amount or non-uniformly at the beginning, and the inside of the heat transfer tube It is possible to deposit more uniformly over a wide range of wall surfaces. In addition, even if the clathrate hydrate originally attached or deposited on the inner wall surface of the heat transfer tube peels off for some reason, the clathrate hydrate is re-applied to the peeled portion every time it is refluxed. Adhering, depositing, and finally removing the peeled portion to a state where the clathrate hydrate is evenly adhered. Therefore, the clathrate hydrate slurry can be stably produced over a long period of time or continuously.
The effects of (f) and (g) described above are that the production apparatus is brought to a stable operation state earlier at the time of initial operation of the clathrate hydrate slurry production apparatus, at the time of restarting operation after a stop or at the time of performance confirmation operation. It can be used for the purpose (see the twelfth to fourteenth aspects of the present invention).
The force due to the flow of the raw material solution is generated by the action of only the raw material solution, but the force due to the flow of the raw material slurry is generated by the action of both the aqueous solution and the hydrate fine particles in the raw material slurry. For this reason, there exists an effect of the following (h).
(H) Increasing the peeling effect by recirculating part or all of the clathrate hydrate slurry or raw material slurry in which the hydrate is dispersed or suspended in the raw material solution to the heat transfer tube as the raw material slurry Can do.
This exfoliation effect becomes higher when the concentration of hydrate fine particles in the raw slurry is high, and hence the viscosity of the raw slurry is high, but so as to increase the cross-sectional area of the flow passage in the heat transfer tube, and thus the heat transfer tube. It works to suppress the increase in pressure loss that occurs when passing through. Therefore, according to the 3rd form of this invention, since the increase in the pressure loss produced when passing a heat exchanger tube can be suppressed, the operating state of the manufacturing apparatus of clathrate hydrate slurry seems to deteriorate rapidly. Can be avoided, and can contribute to the stable production of the clathrate hydrate slurry.

When the clathrate hydrate slurry is produced, the temperature of the refrigerant around the heat transfer tube depends on the change in the refrigerating capacity of the refrigerator that cools the refrigerant, the refrigerating capacity of the refrigerating machine, and the load on the heat utilization side. It varies depending on the balance. Such a change in the refrigerant temperature affects the amount of clathrate hydrate generated by heat exchange through the heat transfer tube and the amount of adhesion to the inner wall surface of the heat transfer tube, and thus the clathrate hydrate slurry. For a long time or continuously, it becomes difficult to manufacture stably.
On the other hand, according to the fourth aspect of the present invention, through the adjustment of the refrigerant temperature, more specifically, the fluctuation of the refrigerant temperature is suppressed or the fluctuation is positively controlled, so that the inside of the heat transfer tube The amount of clathrate hydrate produced in step 1 and the amount of adhesion to the inner wall surface of the heat transfer tube can be adjusted, so that the above problems do not occur and the clathrate hydrate slurry is kept for a long time. Or it can manufacture continuously and stably.
In addition, “the refrigerant temperature is actively controlled to adjust the amount of clathrate hydrate generated inside the heat transfer tube and the amount of adhesion to the inner wall surface of the heat transfer tube” The temperature of the clathrate hydrate is higher than the freezing point of the clathrate hydrate, and at least a part of the clathrate hydrate deposits adhering to the inner wall surface of the heat transfer tube is melted in a short time to It is also included that the amount of adhesion is reduced to zero or very small by removing with. Such an operation is performed when the state of adhesion or deposition of clathrate hydrate on the inner wall surface of the heat transfer tube is not desirable for some reason, and the inner wall surface is in the initial state (that is, completely or almost completely free of inclusion water). Necessary when returning to a state in which the Japanese product is not attached, and is useful for initialization and resetting of the clathrate hydrate slurry production apparatus.

  According to the fifth aspect of the present invention, the temperature of the refrigerant is lower than the freezing point of the clathrate hydrate and is close to the freezing point or the temperature of the aqueous solution or the slurry flowing inside the heat transfer tube, that is, The temperature of the clathrate hydrate is adjusted to be as high as possible at a temperature lower than the freezing point of the clathrate hydrate, so that the increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube It is possible to more effectively perform the suppression by the force of. This will be described in detail.

  When suppressing the increase in the amount of clathrate hydrate adhering to the heat transfer tube only by the flow force of the raw material solution or raw material slurry flowing inside the heat transfer tube, a liquid feed pump with a large output must be adopted. No longer. However, the increase can also be suppressed by adjusting the temperature of the refrigerant. That is, the temperature of the refrigerant is lower than the freezing point of clathrate hydrate, close to the freezing point, or close to the temperature of the aqueous solution or slurry flowing inside the heat transfer tube, that is, lower than the freezing point of clathrate hydrate. If the temperature is set as high as possible, the degree of cooling of the raw material solution or raw material slurry in contact with the heat exchange surface of the heat transfer tube (specifically, the degree of supercooling) becomes small. As a result, the ratio of gaps (content of aqueous solution) in the hydrate deposit formed by cooling on the heat exchange surface of the heat transfer tube increases, the hydrate deposit is soft, and the raw solution or slurry It becomes easy to peel off by the force of the flow.

On the other hand, if the temperature of the refrigerant is made as high as possible at a temperature lower than the freezing point of the clathrate hydrate, it is expected that the exchange heat will be reduced and the ability to produce a hydrate slurry will be reduced. Since the thickness is reduced, the heat resistance in heat exchange is reduced, so that the ability to cool the raw solution or raw slurry is not lowered and the ability to produce a hydrate slurry is not lowered.
As a result, the thickness of the clathrate hydrate adhering to the inner wall surface of the heat transfer tube is generally reduced. Therefore, according to the fifth aspect of the present invention, the flow rate of the raw material solution or the raw slurry can be reduced, the output of the liquid feed pump can be made smaller, a small pump can be adopted, or the energy consumption can be reduced. There is an effect.
Furthermore, the refrigeration for supplying the refrigerant is performed by setting the temperature of the refrigerant at a temperature lower than the freezing point of the clathrate hydrate and close to the freezing point or the temperature of the aqueous solution or slurry flowing inside the heat transfer tube. Since the power consumption of the machine can be reduced, the COP of the hydrate slurry production system can be improved.
By adjusting the temperature of the refrigerant to a temperature lower than the freezing point of the clathrate hydrate and close to the temperature of the aqueous solution or slurry flowing inside the heat transfer tube, it adheres to the inner wall surface of the heat transfer tube as described above. It is possible to more effectively suppress the increase in clathrate hydrates by the flow force of the raw material solution or raw material slurry. In addition, since heat transfer efficiency will become low when the temperature difference of a refrigerant | coolant and a raw material solution or a raw material slurry is made too small, it is preferable to make the temperature of a refrigerant | coolant into 1-4 degreeC temperature lower than the temperature of a raw material solution or a raw material slurry.

  According to the 6th form of this invention, the manufacturing apparatus of the clathrate hydrate slurry based on the manufacturing method which concerns on the 1st form of this invention is realizable.

  According to the 7th form of this invention, the manufacturing apparatus of the clathrate hydrate slurry based on the manufacturing method which concerns on the 2nd form of this invention is realizable.

According to the eighth aspect of the present invention, by providing the turbulence forming means inside the heat transfer tube, turbulence can be formed in the flow of the raw material solution or raw material slurry supplied to the heat transfer tube, and the heat transfer tube The increase in the amount of clathrate hydrate adhering to the inner wall surface of the steel can be more reliably suppressed by the flow force, and the clathrate hydrate slurry can be stably produced over a long period of time or continuously. can do.
In addition, since the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube can be reduced, the heat resistance due to the clathrate hydrate adhering to it decreases, and the heat transfer efficiency from the refrigerant to the raw material solution or slurry Improves and the amount of heat transfer increases. This leads to a reduction in the heat transfer area (the number of heat transfer tubes).
Also, because the flow of the raw material solution or raw material slurry inside the heat transfer tube is disturbed, the efficiency of heat transfer from the refrigerant to the raw material solution or raw material slurry is improved, so that the production capacity of clathrate hydrate slurry is improved. Can do.
Even if the flow rate of the raw material solution or raw material slurry flowing inside the heat transfer tube is reduced as compared with the case where no turbulence forming means is provided, the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube is increased. It can suppress by the force of a flow and can maintain the heat exchange efficiency of a heat exchanger tube. Thereby, the load concerning the pump apparatus for flowing a raw material solution or a raw material slurry can be reduced relatively.

According to the ninth aspect of the present invention, since the heat transfer area of the heat transfer tube is increased, the heat transfer efficiency from the refrigerant to the raw material solution or the raw slurry is improved, so that the production capacity of the clathrate hydrate slurry is improved. be able to.
Further, even if the flow rate of the raw material solution or raw material slurry flowing inside the heat transfer tube is increased as compared with the case where the heat transfer tube is not formed with unevenness, the heat exchange efficiency of the heat transfer tube can be maintained. Thereby, it is possible to more reliably suppress the increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube by the force of the flow, the clathrate hydrate slurry for a long time or continuously, It can be manufactured stably.
In addition, the clathrate hydrate produced tends to remain in the recesses provided on the inner wall surface of the heat transfer tube along the direction in which the raw material solution or the raw material slurry flows. Therefore, a new clathrate hydrate can be generated more easily. Therefore, even if the temperature of the refrigerant is set higher than when the irregularity is not formed in the heat transfer tube, the clathrate hydrate that functions as a generation nucleus remains attached to the concave portion, so that clathrate hydration is ensured. Product slurry can be produced. Therefore, since the clathrate hydrate slurry can be produced even if the temperature of the refrigerant is set high, the load of the refrigerant refrigeration system can be relatively reduced, or the coefficient of performance of the refrigerator can be increased. Can be improved.

  According to the 10th form of this invention, the manufacturing apparatus of the clathrate hydrate slurry based on the manufacturing method which concerns on the 3rd form of this invention is realizable.

According to the 11th form of this invention, the manufacturing apparatus of the clathrate hydrate slurry based on the manufacturing method which concerns on the 4th form of this invention is realizable.
With the combined use of the circulation device in the tenth embodiment and the refrigerant temperature adjustment device in the eleventh embodiment, the amount of clathrate hydrate deposited on the inner wall surface of the heat transfer tube or the deposition thickness of the production apparatus can be finely adjusted. There are also advantages in operation control.
According to the refrigerant temperature control device, the temperature of the refrigerant is set higher than the freezing point of the clathrate hydrate, and at least part of the clathrate hydrate deposits adhering to the inner wall surface of the heat transfer tube is removed for a short time. And then peeled and removed by the force of the raw material solution or raw material slurry, and the amount of adhesion can be made zero or very small. Such an operation is performed when the state of adhesion or deposition of clathrate hydrate on the inner wall surface of the heat transfer tube is not desirable for some reason, and the inner wall surface is in the initial state (that is, completely or almost completely free of inclusion water). Necessary when returning to a state in which the Japanese product is not attached, and is useful for initialization and resetting of the clathrate hydrate slurry production apparatus.

The state of the inner wall surface of the heat transfer tube in the clathrate hydrate slurry production apparatus shows no clathrate hydrate adhering at the first operation of the clathrate hydrate slurry production apparatus, and after At the time of restarting the operation, the clathrate hydrate once adhering melts and part or all of the clathrate detaches and adheres or deposits only unevenly. Since it is made to fluctuate, it cannot be judged correctly whether clathrate hydrate has adhered or whether it has adhered uniformly.
Therefore, according to the twelfth aspect of the present invention, at the initial operation of the clathrate hydrate slurry manufacturing apparatus, at the time of restarting operation after a pause or at the time of performance check operation, A part of the wet hydrate is removed by the flow force of the aqueous solution or the slurry, and the remainder is left so as to cover the inner wall surface of each heat transfer tube, and the raw material solution or the raw slurry that has passed through the heat transfer tube By operating to recirculate part or all to the heat transfer tube at all times or as necessary, the manufacturing apparatus can be brought into a stable operation state earlier by the effects (f) and (g). . Further, the effect (h) is also achieved.

  In addition, in the plurality of heat transfer tubes, the state of the inner wall surface of each heat transfer tube is not the same, but rather differs for each heat transfer tube. In such a case, it is necessary to stabilize the clathrate hydrate slurry production by uniformly depositing and depositing clathrate hydrate on the inner wall surfaces of more heat transfer tubes. Thus, according to the third, tenth and twelfth aspects of the present invention, the clathrate hydrate is uniformly adhered and deposited on the inner wall surface of the heat transfer tube by circulating the raw material solution or the raw material slurry. This is particularly advantageous when the clathrate hydrate slurry manufacturing apparatus includes a plurality of heat transfer tubes.

According to the 13th form of this invention, there exists an effect similar to a 12th form. In addition to this, according to the thirteenth embodiment, the temperature of the refrigerant can be adjusted by the refrigerant temperature adjusting device provided in the clathrate hydrate slurry manufacturing apparatus, and more specifically through the adjustment of the refrigerant temperature. The amount of clathrate hydrate generated inside the heat transfer tube and the amount of adhesion to the inner wall surface of the heat transfer tube can be adjusted by suppressing or actively controlling the variation of the refrigerant temperature. Therefore, it is possible to find conditions that allow normal operation to be performed earlier or more efficiently than in the twelfth embodiment, and to finish the initial operation, resumption operation after stoppage, or performance confirmation operation of the apparatus.
In the present invention, “normal operation” refers to the performance, capability or clathrate hydrate of the production apparatus when the clathrate hydrate slurry production apparatus is continuously operated after the start of operation. It refers to the operation when the production capacity of the slurry converges to a certain value or a certain range without much depending on the operation duration.

Furthermore, according to the thirteenth aspect of the present invention, it becomes possible to finely adjust the adhesion thickness or deposition thickness of the clathrate hydrate on the inner wall surface of the heat transfer tube by using the circulation device and the refrigerant temperature adjustment device together. Further, the advantages of controlling the operation of the clathrate hydrate slurry production apparatus can be obtained.
According to the refrigerant temperature control device, the temperature of the refrigerant is set higher than the freezing point of the clathrate hydrate, and at least part of the clathrate hydrate deposits adhering to the inner wall surface of the heat transfer tube is removed for a short time. And then peeled and removed by the force of the raw material solution or raw material slurry, and the amount of adhesion can be made zero or very small. As described above, this operation is useful for initializing or resetting the clathrate hydrate slurry production apparatus, but in particular for the initial operation of the production apparatus, the restart operation after a pause, the performance check operation, and other normal operations. It is important as an operation to return the inner wall surface of the heat transfer tube to the initial state in order to review the set condition once it is necessary to converge and confirm the necessary condition early by trial and error.

  According to the fourteenth aspect of the present invention, the refrigerant temperature adjusting device can also be used for the refrigerant in the clathrate hydrate slurry production apparatus during the initial operation, the resumption operation after the suspension, or the normal operation after the performance confirmation operation. As in the fourth, fifth and eleventh embodiments, the clathrate hydrate slurry can be stably produced over a long period of time or continuously through the adjustment of the refrigerant temperature. can do.

In order to demonstrate the principle of the present invention, the following experiment was conducted.
[Double tube single tube experiment]
About controlling the amount of hydrate adhering to the inner wall surface of the heat transfer tube by the flow force of the raw material solution or raw material slurry using a double tube heat exchanger corresponding to the shell and tube type heat exchanger, Focusing on the flow rate of the raw material solution or raw material slurry as a parameter related to the flow force, this flow rate was changed, and an experiment was conducted to examine how the hydrate adhesion thickness changes depending on the flow rate of the slurry flowing in the heat transfer tube. It was.

<Experimental equipment>
FIG. 4 is an explanatory diagram of this experimental apparatus.
Insert a SUS304 straight pipe (inner diameter φ15 mm, outer diameter φ18 mm, length 2.5 m) into a SUS pipe with an inner diameter φ28 mm and a length of 2 m. Use a heat exchanger as a tube.
As shown in FIG. 4, the experimental apparatus has four sets of double pipe heat exchangers 51 to 54 connected in series, and a SUS straight pipe (inner diameter φ15 mm) with a length of 1.5 m at one end side (rear stream side). The outer diameter φ18 mm) is connected as the non-cooling section 55.
Thermometers for measuring the temperature in the inner pipe were installed at the connecting parts and both ends of the four sets of double pipe heat exchangers 51 to 54, respectively. A thermometer was also installed at the end of the non-cooling section 55.
A circulation channel 56 for passing the raw material solution or the raw material slurry was provided in the inner pipe of the double pipe heat exchangers 51 to 54. Then, a buffer tank 57 for storing the raw material solution or the raw slurry, a circulation pump 58 with an inverter for circulating the raw material solution or the raw slurry, and a flow rate of the raw material solution or the raw slurry flowing through the circulation passage 56 are detected in the circulation passage 56. A flow meter 59 was installed.
In addition, cold water can be supplied as a refrigerant to the annular portion of the gap between the inner tube and the outer tube in the double tube heat exchangers 51 to 54.
As a raw material solution (a clathrate hydrate aqueous solution), an aqueous solution of tetra n-butylammonium bromide (TBAB) having a concentration of 23 wt% was used. The hydrate formation start temperature of this aqueous TBAB solution is about 10 ° C. Moreover, the temperature of the cold water as a refrigerant | coolant was 6-7 degreeC.

<Experiment method>
In the experimental apparatus configured as described above, the raw material solution is supplied from the buffer tank 57 to the inner pipes of the double-pipe heat exchangers 51 to 54 by the circulation pump 58, while cold water (6 to 7 ° C) in a direction opposite to the aqueous solution to cool the raw material solution in the inner tube.
A hydrate is produced by cooling the raw material solution, and becomes a hydrate slurry of about 8.6 ° C. at the outlet. As the hydrate is generated, the differential pressure in each measurement section (Pd1 to Pd3) increases.
The flow rate of the raw material solution or raw material slurry is changed by changing the pump rotation speed, and the maximum differential pressure at that time is measured.
The flow velocity in the inner pipe is obtained by dividing the flow rate by the cross-sectional area in the pipe.

The thickness of the hydrate adhering to the inner wall of the pipe (apparent adhesion thickness) is obtained by subtracting the differential pressure PdS (corresponding to the pressure loss of the hydrate slurry) of the uncooled part from the measured differential pressure in the measurement section. It is calculated from the differential pressure increase due to the inner diameter change due to the adhesion of the object. Specifically, it was determined as follows.
It is known that when a fluid passes through a pipe, the pressure loss in the pipe is proportional to the square of the flow velocity and inversely proportional to the pipe inner diameter. Therefore, δ was calculated using the following equation, where δ was the apparent adhesion thickness.
Pd3 ₁ '/ Pd3 ₀ = {v ₁ ² / (D-2δ)} / (v ₀ ² / D)
However,
Subscript 0: At the beginning of liquid delivery (aqueous solution) 1: After hydrate formation
v: Flow velocity
D: Inner tube inner diameter δ: Apparent adhesion thickness
Pd3: Differential pressure at the inlet and outlet of the double heat exchanger 54
Pd3 ₁ ': In-pipe pressure loss from which the slurry pressure loss in the double heat exchanger 54 is removed
Pd3 ₁ ′ is obtained by the following equation.
Pd3 ₁ '= Pd3 ₁ − (PdS ₁ −PdS ₀ ) × 2.5 / 1.5

<Experimental result>
(1) Relationship between apparent thickness of clathrate hydrate and flow rate The pressure loss was measured by changing the flow rate, and the apparent thickness of the hydrate was calculated based on the above formula. FIG. 5 is a graph showing the calculation results. In the graph of FIG. 5, the vertical axis represents the apparent adhesion thickness δ, and the horizontal axis represents the flow rate of the raw material solution (in the case of an aqueous solution). As shown in the graph of FIG. 5, the adhesion thickness decreases as the flow rate increases. When the flow velocity exceeds 1.8 m / s, the adhesion thickness decreases rapidly, and thereafter it is understood that there is no rapid change and the same thickness is maintained.
From this, the increase in the adhesion amount of the hydrate to the cooling surface can be suppressed by setting the flow rate of the raw material solution or the raw material slurry on the cooling surface of the heat exchanger to 1.8 m / s or more.

(2) Apparent thickness of clathrate hydrate and change in heat transfer rate over time Differential pressure due to change in inner diameter due to hydrate attachment when the flow rate of the raw material solution is 1.8 m / s (measured differential pressure) The time change of the differential pressure from which the slurry pressure loss was removed) and the time change of the heat transfer rate at which heat input by cold water was transferred to the raw material solution were obtained.

The experimental conditions are as follows.
Raw material solution flow rate: 1.8 m / s
Cold water inlet: 6.4 ° C
Cold water outlet: 6.7 ° C
Raw material solution inlet temperature: 8.9 ° C
Hydrate slurry outlet temperature: 8.6 ° C
Thermal density: 16.6 Mcal / m ³

The differential pressure (differential pressure per meter from which the slurry pressure loss was removed) P and the heat passage rate K1 due to the change in the inner diameter due to adhesion of the hydrate were calculated by the following equations.
P = (Pd1 + Pd2 + Pd3) / (5 + 2.5 + 2.5)-(PdS-PdS ₀ ) /1.5
K1 = Q / AΘ = Cp ・ ρ ・ u (To-Ti) / πDLΘ
However,
Pdn, PdS subscript 0: At the beginning of liquid feeding (aqueous solution) None: After hydrate formation Q: Heat input A: Heat transfer area
Cp: Water specific heat ρ: Water density
u: Cold water flow rate
To: Cold water outlet temperature
Ti: Cold water inlet temperature D: Inner pipe inner diameter L: Heat transfer length Θ: Aqueous solution temperature difference

FIG. 6 is a graph showing the calculation results. In the figure, the vertical axis on the left shows the differential pressure (differential pressure from which slurry pressure loss has been removed) due to changes in the inner diameter due to hydrate adhesion, the vertical axis on the right shows the heat transfer rate, and the horizontal axis shows the test time. ing.
As can be seen from the graph of FIG. 6, the time change of the pressure loss in the heat exchanger tube is substantially constant, and the increase in the pressure loss can be suppressed. Moreover, the heat passage rate is also substantially constant, and an increase in the amount of hydrate adhering to the heat transfer surface can be suppressed to suppress an increase in thermal resistance.
As described above, it has been demonstrated that the hydrate adherence to the heat transfer surface is suppressed by setting the flow rate of the raw material solution or raw material slurry passing through the heat exchanger to 1.8 m / s or more.

[Experiment with shell and tube heat exchanger]
Next, a manufacturing experiment for producing a hydrate slurry by cooling a raw material solution or a raw material slurry with a chlorofluorocarbon refrigerant using a shell and tube heat exchanger will be described.

<Explanation of experimental equipment>
FIG. 7 is an explanatory diagram of this experimental apparatus.
The shell-and-tube heat exchanger is a one-pass heat exchanger in which 27 SUS304 pipes with an outer diameter of 17.3 mm and an inner diameter of 14 mm are arranged in a shell processed from a SUS304 nominal diameter 150A steel pipe. The raw material solution or raw material slurry flows in the tube, and the refrigerant flows to the shell side.

A circulation path 62 for circulating and supplying the raw material solution or raw material slurry to the tube side of the shell and tube heat exchanger 61 is a tank 63 for storing the raw material solution or raw material slurry (the raw material solution is stored at the start of the experiment). A circulation pump 64 provided on the downstream side of the tank 63, and a simulated load electric heater 65 provided on the outlet side of the circulation pump 64.
The tank 63 is provided with a cooling coil (not shown), or hydrate slurry for nucleation is charged, and the supercooled raw material solution sent from the heat exchanger is released.
Experiments can be performed with the temperature of the raw material solution or raw material slurry supplied to the heat exchanger inlet heated by the electric heater 65 for the simulated load so as to offset the cold heat of the hydrate slurry sent from the tank 63. Adjust so that.

In addition, a recirculation flow path 66 that connects the tank 63 and the downstream side of the electric heater 65 in the circulation flow path 62 is provided, and a recirculation pump 67 is provided in the recirculation flow path 66.
The flow rate of the raw material solution or raw material slurry sent to the shell and tube heat exchanger 61 is adjusted to a predetermined amount by adjusting the rotational speed of the pump by an inverter attached to the recirculation pump 67 and the circulation pump 64.

The shell side of the shell-and-tube heat exchanger 61 is supplied with R134a of chlorofluorocarbon refrigerant through the refrigerant circuit 68. The refrigerant circuit 68 is provided with a refrigerant heat exchanger 69, a gas-liquid separator 70, and a refrigerant pump 71. The refrigerant heat exchanger 69 is supplied with the chlorofluorocarbon refrigerant R404a cooled by the refrigerator unit 75 including the compressor 72, the condenser 73, and the expansion valve 74, and performs heat exchange with the refrigerant R134a.
A refrigerant liquid of about 2 ° C. is supplied from the gas-liquid separator 70 into the shell by the refrigerant pump 71, and a part of the refrigerant liquid evaporates in the shell, thereby cooling the raw material solution or raw material slurry in the tube. . The evaporated refrigerant gas and refrigerant liquid are returned to the gas-liquid separator 70. The R134a refrigerant gas separated by the gas-liquid separator 70 is sent to the refrigerant heat exchanger 69, cooled and condensed to become a liquid refrigerant, and returns to the gas-liquid separator 70.

<Experiment method>
In this experiment, a TBAB aqueous solution having a concentration of 14.4 wt% was used as a raw material solution. The hydrate formation start temperature of this aqueous TBAB solution is about 8 ° C.
After adjusting the inverters of the recirculation pump 67 and the circulation pump 64 so as to obtain a predetermined flow rate, the raw material solution or the raw material slurry is circulated through the circulation flow path 62 and the recirculation flow path 66, and then the refrigerator unit 75 and the refrigerant The pump 71 is started and the refrigerant is sent into the shell and tube heat exchanger 61 to cool the raw material solution or raw material slurry in the tube.

The refrigerant temperature in the shell is kept constant by adjusting the compressor 72 in the refrigerator unit 75. When the temperature of the raw material solution at the outlet of the shell-and-tube heat exchanger 61 becomes 7 ° C. or lower and is in a supercooled state, a separately produced hydrate slurry is put into the tank 63 to release the supercooling.
Thereafter, the hydrate slurry temperature at the outlet of the shell & tube heat exchanger 61, the heat exchanger tube pressure loss (difference between the heat exchanger outlet and the inlet) under the condition that the refrigerant temperature, the raw material solution or the raw material slurry flow rate are constant. Pressure).
The sum of the input power of the electric heater 65 for the simulated load and the calorific value of each pump, which is adjusted so as to make the temperature of the raw material solution or raw material slurry flowing into the shell and tube heat exchanger 61 constant, is generated. It corresponds to the retained cold heat of the hydrate slurry, and these are measured and determined as the production capacity of the hydrate slurry.
From the hydrate slurry temperature at the outlet of the shell and tube heat exchanger 61, the solid fraction SPF (the ratio of hydrate in the hydrate slurry) of the hydrate slurry is determined.

<Experimental result 1>
The raw material solution or raw material slurry was passed through the shell and tube heat exchanger 61, and changes with time of various data were examined. FIG. 8 is a graph showing the experimental results when the flow rate of the raw material solution or raw material slurry flowing through the shell and tube heat exchanger 61 is 450 L / min (1.8 m / s in the flow velocity in the tube).
In FIG. 8, the horizontal axis represents time, the left vertical axis represents the tube pressure loss of the shell & tube heat exchanger 61, the solid phase fraction SPF of the hydrate slurry, and the right vertical axis represents the shell & tube heat exchange. It represents the hydrate slurry temperature at the outlet of the vessel 61, the refrigerant temperature at the inlet of the heat exchanger, and the load of the simulated load heater.

After the supercooling is released, the refrigerant temperature at the inlet of the shell & tube heat exchanger 61 is maintained at about 2 ° C, and the hydrate slurry temperature at the outlet of the shell & tube heat exchanger 61 is maintained at 7 ° C. It was confirmed that the experiment was conducted under the conditions.
After the supercooling was released, the tube pressure loss of the shell & tube heat exchanger 61 gradually increased, indicating that the hydrate deposit thickness on the inner wall surface of the tube has increased. After 4 hours, it became almost constant 26 kPa, and it was confirmed that the increase in hydrate adhesion thickness was suppressed.
After the supercooling is released, the load of the simulated load heater gradually decreases, and after 4 hours from the start of operation, it becomes almost constant 3.6 kW, and a hydrate slurry that stably holds the predetermined cold heat is produced. It shows that.
The solid phase fraction SPF of the hydrate slurry also became a substantially constant 14% after 4 hours from the start of operation, indicating that the hydrate slurry was stably produced.

  As described above, when the flow rate in the tube of the raw material solution or raw material slurry flowing through the shell & tube heat exchanger 61 is set to 1.8 m / s, an increase in the hydrate adhesion thickness on the inner wall surface of the tube is suppressed. It was confirmed that the hydrate slurry could be produced stably.

<Experimental result 2>
Next, the recirculation pump 67 and the circulation pump 64 are adjusted to change the flow rate of the raw material solution or raw material slurry flowing in the tube of the shell-and-tube heat exchanger 61 in the range of 1.5 to 2.4 m / s. Experiments were conducted to investigate the relationship between tube pressure loss and aqueous solution flow rate in the tube.

FIG. 9 is a graph showing the experimental results. The horizontal axis represents the raw material solution or raw material slurry flow rate in the tube, and the vertical axis represents the tube pressure loss when the tube pressure loss becomes steady.
As shown in FIG. 9, it was found that when the refrigerant temperature is 2 ° C., the tube pressure loss becomes a low value when the raw material solution in the tube or the raw material slurry flow rate is about 1.8 m / s or more. On the contrary, it was found that the tube pressure loss was high when the flow rate of the raw material solution in the tube or the raw material slurry was less than 1.8 m / s.

  From this result, when the refrigerant temperature is 2 ° C., the shell and tube heat exchanger 61 has a flow rate of 1.8 m / s or more in the raw solution or raw material slurry flow rate in the tube of the shell and tube heat exchanger 61. It was confirmed that if the raw material solution or raw material slurry was circulated through the tube, an increase in the amount of hydrate adhering to the inner wall surface of the tube could be suppressed by the flow force of the raw material solution or raw material slurry. Thereby, heat exchange is performed smoothly for a long time with the tube of the shell & tube type heat exchanger 61, and a hydrate slurry can be manufactured stably.

  Moreover, if the raw material solution or the raw material slurry is circulated so that the flow rate of the raw material solution or the raw material slurry in the tube of the shell & tube heat exchanger 61 is 1.8 m / s or more, the hydration adhered to the inner wall surface of the tube It is possible to suppress the increase in the amount of material and to leave the hydrate partially attached to the inner wall surface of the tube, so that the remaining hydrate functions as a hydrate crystal formation nucleus, so a new hydrate Can be easily generated, the solid phase fraction of the hydrate slurry can be in an appropriate range, and the cold energy can be stored or transported smoothly.

<Experimental result 3>
The effect of the refrigerant temperature was examined by changing the refrigerant temperature. The shell and tube heat exchanger 61 is changed from 0 to 4.7 ° C. at a temperature lower than 8 ° C. which is the hydrate formation start temperature (hydrate freezing point) of the 14.4 wt% TBAB aqueous solution. A manufacturing test was conducted to examine the influence of the refrigerant temperature on the pressure loss of the tube portion of the shell-and-tube heat exchanger 61. The flow rate of the raw material solution or raw material slurry in the heat exchanger tube was 2 m / s.
FIG. 10 shows a graph of the experimental results. The horizontal axis represents the refrigerant temperature, and the vertical axis represents the pressure loss of the tube portion of the shell & tube heat exchanger 61 and the cooling capacity of the shell & tube heat exchanger 61.

As shown in FIG. 10, the tube portion pressure loss of the shell-and-tube heat exchanger 61 decreases as the refrigerant temperature increases in the experimental temperature range. The reason is considered as follows.
If the temperature of the refrigerant is as high as possible within the range lower than the freezing point of the clathrate hydrate (in other words, closer to the freezing point of the clathrate hydrate), the raw material solution or the raw material in contact with the heat exchange surface of the heat transfer tube The degree of cooling of the slurry (specifically, the degree of supercooling) becomes small. As a result, the ratio of gaps in the hydrate deposit layer (content of aqueous solution) generated by cooling on the heat exchange surface of the heat transfer tube increases, and the hydrate deposit layer is soft and the aqueous solution or hydrate slurry. It becomes easy to peel off by the force of the flow. The higher the refrigerant temperature is, the softer the hydrate deposit layer adhering to the inner surface of the heat transfer tube becomes, and it is easy to be peeled off, and the amount of hydrate is suppressed. As a result, the higher the refrigerant temperature, the smaller the heat exchanger tube pressure loss.

  The cooling capacity of the shell & tube heat exchanger 61 is determined as follows. When the refrigerant temperature is in the range of 0 to 4 ° C, the cooling capacity per unit length of the tube is 0.095 to 0.097 [kW / m / tube]. ], It is almost constant regardless of the refrigerant temperature. When the refrigerant temperature is high, the refrigerator that supplies the refrigerant in order to obtain the same cooling capacity can be operated under a high refrigerant temperature condition, so that the power consumption of the refrigerator can be reduced.

Calculation of cooling capacity of heat exchanger Cooling capacity Q = A ・ K ・ ΔTm
However, A: Heat transfer area [m ² ] = π · Do · L · n
K: Heat transfer rate [W / m ² k]
ΔTm: Logarithmic average temperature difference (≒ Ti-To)
To: Refrigerant temperature
Ti: Raw material solution or raw material slurry temperature in the tube
Do: Tube outer diameter
D: Diameter of aqueous solution channel in tube
t: Tube tube thickness
σ: Hydrate layer thickness
ho: Heat transfer coefficient outside the tube
h i: Heat transfer coefficient in the tube λ _SUS : SUS tube heat conductivity λ _CHS : Hydrate heat conductivity The heat transfer rate is obtained from the following equation.

<Experimental result 4>
Furthermore, the effect of the refrigerant temperature on the pressure loss in the tube portion of the shell and tube heat exchanger 61 was also examined when the type of raw material slurry and the flow rate were changed.
Using a 14.4 wt% TBAB aqueous solution (hydrate formation start temperature (hydrate freezing point) 8 ° C.) as a raw material solution, the hydrate was formed by cooling in advance, and the solid phase fraction SPF was 15% and 20%. A hydrate slurry was prepared and used as a raw slurry.
The temperature of the SPF 15% hydrate slurry produced from the 14.4 wt% TBAB aqueous solution is 7 ° C., and the temperature of the SPF 20% hydrate slurry is 6 ° C.
In addition, an 11 wt% TBAB aqueous solution (hydrate formation start temperature (freezing point of hydrate) 7 ° C.) was cooled in advance to produce a hydrate, and hydrated with a solid fraction of SPF of 15% and 20%. A product slurry was produced and used as a raw material slurry. The temperature of the SPF 15% hydrate slurry prepared from the 11 wt% TBAB aqueous solution is 5 ° C., and the temperature of the SPF 20% hydrate slurry is 4 ° C.
That is, the following four types of raw material slurry were used.
(1) A hydrate slurry having a solid phase fraction SPF of 15% obtained by cooling a 14.4 wt% TBAB aqueous solution
(2) A hydrate slurry having a solid phase fraction SPF of 20% obtained by cooling a 14.4 wt% TBAB aqueous solution.
(3) A hydrate slurry with a solid phase fraction SPF of 15% obtained by cooling an 11 wt% TBAB aqueous solution.
(4) Hydrate slurry of 11wt% TBAB aqueous solution with solid phase fraction SPF 20%

  For the above four types of raw material slurry, the refrigerant temperature was changed from 0 to 4.7 ° C. at a temperature lower than the respective hydrate production start temperature (the freezing point of the hydrate), and the recirculation pump 67 and Experiments were conducted by adjusting the circulation pump 64 and changing the flow rate of the raw slurry flowing in the tube of the shell & tube heat exchanger 61 in the range of 1.6 to 2.4 m / s, and the refrigerant against the pressure loss of the tube part The effect of temperature was investigated. And the thickness of the hydrate adhering to the inner surface of the tube was calculated from the pressure loss measurement value of the tube portion in the same manner as in the double tube single tube experiment.

FIG. 11 and FIG. 12 show graphs of experimental results. 11 and 12, the horizontal axis represents the refrigerant temperature, and the vertical axis represents the equivalent adhesion thickness of the hydrate calculated from the pressure loss value of the tube portion of the shell-and-tube heat exchanger 61.
FIG. 11 shows the experimental results for the raw slurry produced from the 14.4 wt% TBAB aqueous solution, and FIG. 12 shows the experimental results for the raw slurry produced from the 11 wt% TBAB aqueous solution.

  As shown in FIGS. 11 and 12, the hydrate equivalent deposition thickness decreases as the refrigerant temperature increases for any raw material slurry and for any flow rate. The higher the refrigerant temperature, the softer the hydrate deposit layer that adheres to the inner surface of the heat transfer tube, and the amount of hydrate that adheres more easily by the flow force of the aqueous solution or hydrate slurry is suppressed. This can be confirmed by changing the slurry type and flow rate.

Next, based on the experimental results shown in FIGS. 11 and 12, the relationship between the temperature difference between the refrigerant and the raw slurry and the equivalent adhesion thickness of the hydrate was examined. The graph of this result is shown in FIGS. The horizontal axis represents the temperature difference between the refrigerant temperature and the raw slurry, and the vertical axis represents the equivalent adhesion thickness of the hydrate calculated from the pressure loss value of the tube portion of the shell and tube heat exchanger 61.
FIG. 13 shows the results for the raw slurry produced from the 14.4 wt% TBAB aqueous solution, and FIG. 14 shows the results for the raw slurry produced from the 11 wt% TBAB aqueous solution.

  As shown in FIGS. 13 and 14, the hydrate equivalent deposition thickness decreases as the temperature difference between the refrigerant and the raw slurry decreases for any raw slurry and for any flow rate. The smaller the temperature difference between the refrigerant and the raw material slurry, that is, the higher the refrigerant temperature, the softer the hydrate deposit layer adhering to the inner surface of the heat transfer tube, and the more easily peeled off due to the flow force of the aqueous solution or hydrate slurry. It can be confirmed that the amount of hydrate is suppressed even if the type and flow rate of the raw slurry are changed.

  Next, the relationship between the adhesion thickness of the hydrate adhering to the inner surface of the tube of the shell and tube heat exchanger 61 and the pressure loss of the tube portion was examined. FIG. 15 is a graph showing the results, where the horizontal axis indicates the adhesion thickness, and the vertical axis indicates the pressure loss increase rate when the hydrate does not adhere to 100%. Since the pressure loss in the tube portion is proportional to the square of the flow velocity and inversely proportional to the effective inner diameter of the tube, the effective inner diameter decreases and the pressure loss increases as the adhesion thickness increases.

From the viewpoint of the allowable range of fluctuations in pump power for feeding the raw material solution or raw slurry, it is preferable to increase the pressure loss increase rate of the tube portion of the shell & tube type heat exchanger to 150% or less. According to the graph of FIG. 15, it is necessary to set the adhesion thickness of about 0.5 mm or less. In order to make the hydrate adhesion thickness about 0.5 mm or less, it is preferable to set the temperature difference between the refrigerant and the raw slurry to 4 ° C. or less from FIGS.
Further, if the temperature difference between the refrigerant and the raw material slurry is too small, the heat transfer efficiency is lowered, so that the temperature difference needs to be 1 ° C. or more. In this way, by setting the temperature difference between the refrigerant and the raw slurry to 1 ° C. or more and 4 ° C. or less, heat exchange can be performed with appropriate heat transfer efficiency, and an increase in the thickness of the hydrate attached to the inner surface of the tube can be suppressed. .

[Embodiment 1]
FIG. 16 is an explanatory view illustrating the configuration of the clathrate hydrate slurry manufacturing apparatus according to one embodiment of the present invention.
The clathrate hydrate slurry manufacturing apparatus according to the present embodiment includes a heat exchanger 1 that performs heat exchange between a raw material solution (an aqueous solution of a guest compound that generates a hydrate) or a raw material slurry and a refrigerant, A refrigerant supply device 21 for supplying refrigerant to the exchanger 1, a heat storage tank 5 for storing the raw material solution or raw material slurry and the generated hydrate slurry, one end communicating with the heat storage tank 5, and the other end being a heat exchanger 1 is connected to the inlet side of the heat exchanger 1, the outlet side channel 9 is connected to the outlet side of the heat exchanger 1, and the other side is connected to the heat storage tank 5. And a recirculation flow path 12 for connecting the side flow paths 9.
The heat exchanger 1 is a shell-and-tube heat exchanger, and is configured such that a fluorocarbon refrigerant such as R134a flows on the shell side and a raw material solution or raw material slurry flows on the tube side.

  The refrigerant supply device 21 includes a compressor 2 that compresses a gas refrigerant, a condenser 3 that condenses the compressed gas refrigerant into a liquid refrigerant, a refrigerant pipe 4, and a refrigerant temperature that is supplied to the heat exchanger by controlling the refrigerant flow rate. A refrigerant flow rate control device (an inlet guide vane in the case of a turbo compressor) 19 is provided as a refrigerant temperature adjusting device for adjusting the pressure.

  The aqueous solution in the heat storage tank 5 is sent to the upstream side of the connecting portion 10 with the recirculation flow path 12 in the inlet side flow path 8 (the upstream side in the input side flow path 8 means the side close to the heat storage tank 5). For this purpose, a manufacturing pump 6, a flow meter 14 </ b> B that measures the flow rate of the aqueous solution, and a first thermometer 17 that measures the temperature of the aqueous solution are installed.

The recirculation flow path 12 is provided with a storage tank 13, a recirculation pump 7 that sends out the hydrate slurry, and a second thermometer 16 that measures the temperature of the hydrate slurry.
The storage tank 13 is provided with a supercooling release device (not shown) that releases supercooling of the supercooled aqueous solution supplied.

  Examples of the supercooling release device include a cooling unit connected to a small refrigerator, and the cooling unit is inserted into a pipe through which a supercooled aqueous solution passes. The cooling part is cooled to a hydrate formation temperature or lower by a small refrigerator, and the hydrate adheres to the surface. When the supercooled aqueous solution comes into contact with the cooling part, the hydrate adhering to the surface of the cooling part acts as a generation nucleus, the supercooling is released, and a hydrate is easily generated.

  Further, as the overcool release device, a low temperature protrusion made of a supercooled Peltier element or the like may be inserted into a pipe through which a supercooled aqueous solution passes. Such low-temperature protrusions are also cooled to a hydrate formation temperature or lower like the cooling part of the small refrigerator described above, and hydrates adhere to the surface. When the supercooled aqueous solution comes into contact with the low-temperature protrusions, the hydrate attached to the surface of the low-temperature protrusions acts as a formation nucleus, and the supercooling is released, so that a hydrate is easily generated.

Further, as a supercooling release device, a hydrate slurry produced separately may be added.
The flow rate of the mixture of the raw material solution or the raw material slurry and the hydrate slurry supplied from the recirculation flow channel 12 is measured on the downstream side of the connecting portion 10 with the recirculation flow channel 12 in the inlet flow channel 8. A flow meter 14A and a third thermometer 15 for measuring the temperature of the mixture are installed.

  In addition, on the upstream side of the connecting portion 11 with the recirculation channel 12 in the outlet side channel 9 (the upstream side in the outlet side channel 9 means a side close to the heat exchanger 1), the heat exchanger 1. A fourth thermometer 18 is installed to measure the temperature of the raw material solution or the raw material slurry or hydrate slurry flowing out from the water. Further, an opening / closing valve 41 is installed on the outlet side channel 9 on the downstream side of the connecting portion 11 with the recirculation channel 12.

Also, the hydrate slurry production apparatus inputs the measured values of the flow meter 14, the first thermometer 17, the second thermometer 16, and the third thermometer 15, and produces the production pump 6 and / or the recirculation pump. The control means 30 which controls the flow volume of 7 is provided.
An air conditioning load 20 is connected to the heat storage tank 5 by a hydrate slurry pipe for receiving the supply of hydrate slurry stored in the heat storage tank 5 and performing air conditioning.

The operation of the present embodiment configured as described above will be described.
<Overview of hydrate production>
A fluorocarbon refrigerant such as R134a flows on the shell side of the heat exchanger 1, and a raw material solution or raw material slurry flows on the tube side.
From the heat storage tank 5, an aqueous solution of 12 to 15 ° C. is taken out by the production pump 6 and supplied to the heat exchanger 1 through the inlet side pipe 8.
The raw material solution or raw material slurry supplied to the heat exchanger 1 is compressed by the compressor 2 and cooled by the heat that the CFC liquid refrigerant liquefied by the condenser 3 evaporates in the shell, thereby producing a hydrate slurry. The The hydrate slurry from the heat exchanger 1 passes through the outlet pipe 9 and is sent to the heat storage tank 5 for storage.
When the raw material slurry is supplied from the heat storage tank 5 to the heat exchanger 1, a hydrate is further generated, and a hydrate ratio in the hydrate slurry, that is, a hydrate with a high solid phase fraction (SPF). A product slurry is produced.
The hydrate slurry stored in the heat storage tank 5 is sent to the air conditioning load 20 to supply cold heat, and the hydrate slurry having a low aqueous solution or solid phase fraction returns to the heat storage tank 5.

<Description of operation method of manufacturing equipment>
An operation method of a production apparatus for producing a hydrate slurry using tetra nbutylammonium bromide (TBAB) as an example of a guest compound for producing a hydrate will be described. The description will be divided into a preparatory operation, which is the initial operation or a resumption operation after a pause, and a normal operation in which a hydrate slurry is regularly produced.
When the aqueous solution concentration is 14.4 wt%, the hydrate formation start temperature is 8 ° C. The solid phase fraction (SPF) of the hydrate slurry at 7 ° C. is 14%, and the heat density is 14 Mcal / m ³ (based on 14 ° C.).

<Preparation operation>
[1] At the start of hydrate slurry production, a raw material solution of 12 ° C. or higher exists in the inlet side channel 8, the outlet side channel 9 and the tubes in the heat exchanger 1, and the heat storage tank 5 and the storage tank 13 store a raw material solution of 12 ° C. or higher.
At the start of hydrate slurry production, the on-off valve 41 is closed. The recirculation pump 7 is started, the flow rate of the raw material solution in the tube in the heat exchanger 1 is detected by the flow meter 14A so that the flow rate is constant at a predetermined flow rate, and the flow rate is adjusted by adjusting the inverter of the recirculation pump 7. Control. The flow path of the raw material solution at this time is 13 → 7 → 12 → 14A → 8 → 1 → 9 → 13.
[2] Next, the compressor 2 of the refrigerator is started, the refrigerant is supplied to the heat exchanger 1, and the raw material solution flowing in the tube is cooled. The control of the refrigerator during cooling is performed by, for example, compressor capacity control device (inverter) or refrigerant flow rate control device 19 (inlet in the case of a turbo compressor) so that the refrigerant evaporation temperature (pressure) in the shell becomes a predetermined value. Adjust guide vanes. The raw material solution is cooled to a supercooled state in the tube of the heat exchanger 1.

[3] When the raw material solution is circulated while cooling the flow path of 13 → 7 → 12 → 14A → 8 → 1 → 9 → 13 and the temperature of the raw material solution in the storage tank 13 becomes close to the hydrate formation temperature. Then, the cooling pipe built in as the supercooling release device is cooled, and hydrate is attached to the surface of the cooling pipe. When the raw material solution cooled to the supercooled state in the heat exchanger 1 touches the hydrate adhering to the surface of the cooling pipe, the adhering hydrate becomes a hydrate formation nucleus and the supercooling is released. A product is produced and a hydrate slurry is produced and stored. When the supercooling is released, the temperature in the storage tank 13 rises to the target hydrate slurry temperature. When a certain amount of hydrate slurry is stored in the storage tank 13, the preparatory operation is terminated and the normal operation is started.
If the solid fraction of the hydrate slurry flowing into the storage tank 13 becomes larger than 0, the cooling of the cooling pipe may be stopped. The calculation method of the solid phase fraction will be described later.

<Normal operation>
[4] The on-off valve 41 is opened, the production pump 6 is started, the raw material solution in the heat storage tank 5 is allowed to flow into the inlet-side flow path 8, and the operation of the recirculation pump 7 is continued to keep water in the storage tank 13. The Japanese slurry is supplied to the inlet channel 8 through the recirculation channel 12. Thereby, the hydrate slurry from the storage tank 13 is supplied to the raw material solution, and the hydrate slurry having a low solid phase fraction is supplied to the heat exchanger 1. The hydrate slurry having a low solid fraction is cooled in the heat exchanger 1 to further produce a hydrate, and a hydrate slurry having a predetermined solid fraction is produced.

The hydrate slurry produced by the heat exchanger 1 is sent to the outlet channel 9, part of which is supplied to the recirculation channel 12, and the rest is supplied to the heat storage tank 5 and stored. The hydrate slurry supplied to the recirculation flow path 12 is stored in the storage tank 13 and supplied again to the inlet flow path 8 by the recirculation pump 7. On the other hand, the hydrate slurry supplied to the heat storage tank 5 is stored in the heat storage tank 5 until it is supplied to the air conditioning load 20. In addition, the temperature of the hydrate slurry sent from the heat exchanger 1 is measured by the fourth thermometer 18 to obtain the solid phase fraction, and the operation of the hydrate slurry production apparatus so as to obtain the desired solid phase fraction. Continue.
The hydrate slurry stored in the heat storage tank 5 is supplied to the air conditioning load 20 and used for indoor cooling or the like.

  At this time, the flow rate of the hydrate slurry having a low solid fraction to be supplied to the heat exchanger 1 is measured by the flow meter 14A, and the hydrate slurry having a low solid fraction in the tube of the heat exchanger 1 is measured. The flow rate is adjusted so that the production pump 6 and the production pump 6 have a flow rate of 1.8 m / s or more so that a part of the hydrate attached to the inner wall surface of the tube is removed by the flow force and the remaining portion remains on the inner wall surface of the tube. The flow rate is controlled by adjusting the inverter of the circulation pump 7 to set the flow velocity. Here, the flowmeter 14A, the inverter of the production pump 6 and the recirculation pump 7 function as a flow rate setting device.

[5] Further, hydrate particles remain in the mixture of the raw material solution from the heat storage tank 5 and the hydrate slurry from the storage tank 13, that is, hydration with a low solid fraction after mixing. The flow rates of the raw material solution from the heat storage tank 5 and the hydrate slurry from the storage tank 13 are adjusted so that the solid phase fraction of the product slurry does not become zero. In this manner, since the hydrate microparticles flow into the heat exchanger 1 in the presence of the hydrate microparticles, the hydrate microparticles function as a generation nucleus to generate a hydrate, and the heat exchanger 1 Does not enter a supercooled state, so it is possible to produce a stable hydrate slurry without causing problems such as a sudden release of supercooling in the tube, resulting in excessive pressure loss or blockage. .

Here, the flow rate adjustment method of the raw material solution from the heat storage tank 5 and the hydrate slurry from the storage tank 13 will be described.
When the aqueous solution of the guest compound that forms a hydrate is cooled, hydrate particles are formed when the temperature falls below the hydrate formation temperature, and the hydrate particles are dispersed or suspended in the aqueous solution to form a hydrate slurry. The As cooling continues, the hydrate particles increase and the solid fraction (referred to the weight ratio of hydrate particles to hydrate slurry) increases. There is a certain relationship between the temperature of the hydrate slurry and the solid fraction, depending on the initial concentration of the aqueous solution of the guest compound that produces the hydrate.

  For example, the graph of FIG. 17 shows the relationship between the temperature of the hydrate slurry of an aqueous solution of tetra n-butylammonium bromide (TBAB) having an initial concentration of 14 wt% and the solid fraction. In this example, as shown in FIG. 17, when the hydrate slurry temperature is low, the solid fraction is high, and when the hydrate slurry temperature is 8.4 ° C. or higher, the solid fraction becomes zero.

  In the present embodiment, the hydrate particles remain in the mixture of the raw material solution from the heat storage tank 5 and the hydrate slurry from the storage tank 13, that is, the solidified hydrate slurry after mixing. The flow rates of the raw material solution and the hydrate slurry to be fed are adjusted so that the phase fraction does not become zero. For example, when the temperature of the raw material solution from the heat storage tank 5 is 12 ° C. or higher and the temperature of the hydrate slurry from the storage tank 13 is 7 ° C., the flow rate of the raw material solution is the hydrate slurry from the storage tank 13. If it is excessive as compared with the flow rate of, the temperature of the hydrate slurry after mixing becomes higher than the temperature at which the solid phase fraction becomes 0, and hydrate particles do not exist.

  In other words, the temperature of the mixture in which the hydrate slurry from the storage tank 13 is supplied to the raw material solution is set to 0 so that the solid fraction of the hydrate slurry after mixing does not become zero. The flow rate of the raw material solution and the hydrate slurry from the storage tank 13 is adjusted so as to be lower than the above temperature. Specifically, it is performed as follows.

  As shown in FIG. 16, the flow rate and temperature of the raw material solution sent from the heat storage tank 5 are measured by the flow meter 14 </ b> B and the first thermometer 17, and the measured values are input to the control means 30. Further, the temperature of the hydrate slurry sent from the storage tank 13 is measured by the second flow meter 16, and the measured value is input to the control means 30. Further, the flow rate and temperature of the mixture of the raw material solution sent to the heat exchanger 1 and the hydrate slurry sent from the storage tank 13 are measured by the flow meter 14 </ b> A and the third thermometer 15, and the measured values are sent to the control means 30. Entered. The flow rate of the hydrate slurry sent from the storage tank 13 corresponds to the difference between the measured values of the flow meter 14A and the flow meter 14B.

Based on each input measurement value, the control means 30 controls the solid phase fraction of the mixture supplied with the hydrate slurry sent from the storage tank 13 to the raw material solution to be greater than 0, It is sent to the heat exchanger 1. That is, the production pump 6 and / or the temperature of the mixture in which the hydrate slurry fed from the storage tank 13 to the raw material solution is set to a predetermined temperature lower than the temperature at which the solid phase fraction becomes zero. Alternatively, the flow rate of the recirculation pump 7 is controlled.
After adjusting the pump flow rate, the flow rate and temperature of the mixture are measured by the flow meter 14A and the third thermometer 15, and the measured values are input to the control means 30 to determine whether the flow rate and temperature are the target values. If not, the flow rate of the production pump 6 and / or the recirculation pump 7 is controlled so that the target flow rate and temperature are reached.

  By adjusting the flow rate as described above, the hydrate particles flow into the heat exchanger 1 with the hydrate particles remaining in the mixture in which the hydrate slurry sent from the storage tank 13 to the raw material solution is supplied. When the raw material solution containing the hydrate particles is cooled by the heat exchanger 1, hydrates are generated with the hydrate particles as nuclei, and therefore, the heat exchanger 1 does not become supercooled. Stable hydrate slurry can be produced without causing problems such as excessive supercooling release in the tube and excessive pressure loss or obstruction.

  As described above, in the present embodiment, the flow rate of the hydrate slurry or raw material solution having a low solid phase fraction supplied to the heat exchanger 1 is adjusted, and the flow rate in the tube of the heat exchanger 1 is adjusted. The flow rate is set so that a part of the hydrate adhering to the inner wall surface of the tube is removed by the force of the flow and the remaining portion remains on the inner wall surface of the tube, for example, 1.8 m / s or more. Since the hydrate particles are included in the raw material solution supplied to the heat exchanger 1, the hydrate slurry can be stably produced without causing the supercooling release in the heat exchanger 1.

  In addition, since the recirculation flow path 12 is provided and the storage tank 13 provided with the supercooling release device is installed in the recirculation flow path 12, water is not released in the heat exchanger 1 even during the preparatory operation. A Japanese slurry can be produced.

In the above embodiment, the flow rate adjustment by the control means 30 is performed by the flow rate control of the production pump 6 and / or the recirculation pump 7. A control valve may be provided to control this flow control valve.
In addition, the flow control valve provided in the inverter or recirculation flow path 12 provided in the inverter or recirculation flow path 12 which adjusts the operation | movement of the recirculation pump 7 and / or the flow control valve provided in the inverter or the inlet flow path 8 which adjusts the driving | operation of the production pump 6 The flow meter 15 corresponds to a flow rate setting device that sets the flow rate of the raw material solution or raw material slurry of the present invention.
In the above embodiment, as a refrigerant temperature adjusting device for adjusting the temperature of the refrigerant supplied to the heat exchanger, a refrigerant flow rate control device that controls the flow rate of refrigerant supplied to the heat exchanger (inlet guide in the case of a turbo compressor). Although the case where the vane 19 or the compressor capacity control device (inverter) is provided has been described as an example, the refrigerant temperature may be adjusted by other methods.
In the above embodiment, the case where the heat exchanger is an evaporator of a compression refrigerator is taken as an example, but the heat exchanger may be of a type that exchanges heat with cold water cooled by the refrigerator. Alternatively, another refrigerator may be used.

Moreover, in said embodiment, it was set as the structure of the manufacturing apparatus which provided the recirculation flow path 12. FIG. However, without providing such a recirculation flow path 12, the hydrate slurry in the heat storage tank 5 is discharged and the solid phase fraction of the mixture becomes larger than 0 in the input flow path 8 as described above. You may make it supply as follows.
Further, in the above example, it is stated that the solid phase fraction is larger than 0. However, the optimum solid phase fraction is appropriately determined depending on the type of hydrate and the like. It is preferable to set.

Examples of hydrate-forming substances that form hydrates and have a high latent heat amount include various salts such as tetra-n-butylammonium salt, tetraisoamylammonium salt, tetraisobutylphosphonium salt, and triisoamylsulfonium salt. Examples of tetra n butyl ammonium salts include tetra n butyl ammonium bromide ((n-C ₄ H ₉ ) ₄ NBr, TBAB), tetra n-butyl ammonium fluoride ((n-C ₄ H ₉ ) ₄ NF ), tetra-n-butylammonium chloride _{((n-C 4 H 9} ) 4 NCl), and the like.
Instead of Br, F, and Cl, acetic acid (CH ₃ CO ₂ ), chromic acid (CrO ₄ ), tungstic acid (WO ₄ ), oxalic acid (C ₂ O ₄ ), and phosphoric acid (HPO ₄ ) may be used. . The same applies to the other salts.

Next, an example of a heat storage air conditioning system using the hydrate slurry production apparatus of the present invention is shown in the following examples.
In the description of the following examples, the flow rate of the hydrate slurry production apparatus, the measurement / control equipment necessary for temperature control, and the supercooling release storage tank are omitted.

[Heat storage air conditioning system 1]
In the heat storage air-conditioning system 1 according to the first embodiment, the slurry production refrigerator is operated to store heat at night, performs cooling operation to dissipate the heat during the daytime, and the slurry production refrigerator is operated when the daytime cooling load is high. Perform heat-dissipating cooling operation while operating and storing heat. One of the features is that one slurry production refrigerator can handle even during daytime cooling loads.

FIG. 18 is an explanatory diagram of a device configuration of the first embodiment, and shows a device configuration when applied to a building corresponding to the maximum cooling load 400RT.
The heat storage air conditioning system 1 according to the first embodiment includes a slurry production refrigerator 81 that produces a hydrate slurry, a heat storage pump 82 that is provided in a hydrate slurry production line and circulates a raw material solution or raw material slurry, and a recirculation flow A recirculation pump 84 provided in the passage 83, a heat storage tank 85 for storing the raw material solution or raw material slurry or hydrate slurry, and a cold water / slurry heat exchanger 86 for generating cold water by heat exchange between the hydrate slurry and water. , A heat radiation pump 87 for sending the hydrate slurry of the heat storage tank 85 to the cold water / slurry heat exchanger 86, a cold water primary pump 88 for circulating the cold water, a cold water secondary pump 89 for sending the cold water to the load side, and air conditioning And a load 90.

The raw material solution used in Example 1 is an aqueous solution of tetra n-butylammonium bromide (TBAB), the concentration is 12.4 wt%, and the hydrate formation start temperature is 7.5 ° C. The amount of heat supplied when the hydrate slurry changes from 5.5 ° C. to 12.5 ° C. is about 14 Mcal / m ³ , and the solid phase fraction (SPF) when the hydrate slurry is 5.5 ° C. is 17%.
The slurry manufacturing refrigerator 81 is a turbo refrigerator and includes a compressor, an evaporator, and a condenser. The raw material solution or the raw material slurry flows through the tube of the shell and tube heat exchanger, which is an evaporator. Further, a fluorocarbon refrigerant such as R134a flows on the shell side, and the raw material solution or the raw material slurry flowing in the tube is cooled by latent heat that the fluorocarbon refrigerant evaporates.
The recirculation pump 84 has an effect of setting the flow rate of the raw material solution or the raw material slurry flowing in the tube to a predetermined flow rate or higher in order to suppress an increase in the amount of hydrate adhered in the tube.
The heat storage pump 82 is a pump having the same role as the manufacturing pump described above.
The heat storage tank 85 is a multi-tank connection tank and can store a heat storage amount of about 2000 RTh.
The hydrate slurry is extracted from the heat storage tank 85 and sent to the cold water / slurry heat exchanger 86 by the heat radiating pump 87, and the cold water is supplied to the cold water by the cold water / slurry heat exchanger 86.
The chilled water cooled by the chilled water / slurry heat exchanger 86 is sent to the air conditioning load 90 by the chilled water primary pump 88 and the chilled water secondary pump 89 to supply the chilled heat and supplied to the cooling.

<Heat storage operation>
At night, the slurry production refrigerator 81, the recirculation pump 84, and the heat storage pump 82 are operated, and a predetermined hydrate slurry (5.5 ° C., SPF 17%) is stored in the heat storage tank 85 to store heat.
In the heat storage tank 85 before the start of heat storage, a raw material solution of approximately 12.5 ° C. is stored, and when heat storage is completed, it is approximately filled with a hydrate slurry of 5.5 ° C. and 17% SPF.

<Cooling operation using heat storage>
When a cooling load occurs in the building during the daytime, the chilled water primary pump 88 and the heat dissipation pump 87 are started, and the chilled water / slurry heat exchanger 86 extracts the 5.5 ° C from the heat storage tank 85 by the heat dissipation pump 87. A heat dissipation operation for producing 7 ° C. cold water is performed by heat exchange between the hydrate slurry and the cold water. Moreover, the cold water secondary pump 89 is started, cold water is supplied to the air-conditioning load 90 which consists of an indoor air conditioner, and it uses for air_conditioning | cooling.

<Additional heat storage / cooling operation>
When the cooling load of one day is expected to be 2000 RTh or more of the heat storage amount, the slurry production refrigerator 81, the recirculation pump 84, and the heat storage pump 82 are operated to perform additional heat storage and simultaneously perform a heat radiation operation.

[Heat storage air conditioning system 2]
The heat storage air-conditioning system 2 according to the second embodiment is based on the fact that the refrigerator for slurry production is operated and stored at night and the cooling operation is performed to dissipate the heat during the day. Cold water is produced by a machine so that it can be complemented.

  FIG. 19 is an explanatory diagram of the device configuration of the second embodiment, and the same components as those in FIG. 18 are denoted by the same reference numerals. As shown in FIG. 19, in the second embodiment, in the configuration shown in FIG. 18, a cold water refrigerator 91 for producing cold water at 7 ° C., and a cold water primary pump for sending cold water from the cold water refrigerator 91 92 is added.

  Nighttime heat storage operation and daytime heat storage cooling operation are performed in the same manner as in the first embodiment. When the cooling load of the day is 2000 RTh or more, which is a heat storage amount, the cold water refrigerator 91 (200 RT) is operated to supply cold water, and combined with the cold water cooled by the heat radiation of the hydrate slurry in the heat storage tank 85. The air conditioning load 90 is supplied.

[Heat storage air conditioning system 3]
This embodiment is characterized in that the refrigerator is a double evaporator type in which the refrigerant is switched between a slurry producing evaporator and a cold water producing evaporator. Basically, the slurry is manufactured and stored at night to store heat, and the stored heat is dissipated during the day to perform cooling operation.

FIG. 20 is an explanatory diagram of a device configuration of the third embodiment, and the same reference numerals are given to the same portions as those in FIG.
The slurry / chilled water manufacturing refrigerator 93 of the third embodiment is a refrigerator that includes a cold water manufacturing evaporator 94 and a hydrate slurry manufacturing evaporator 95. By switching the flow of CFC refrigerant, Or a hydrate slurry can be produced.
During the nighttime heat storage, the hydrate slurry is produced and stored using the evaporator 95 for producing the hydrate slurry.
In the daytime, the heat storage of the hydrate slurry in the heat storage tank 85 is dissipated to perform cooling operation, and when the cooling load is high, the slurry / cold water production refrigerator 93 is operated and the cold water production evaporator 94 is used. Cold water is manufactured and supplied to the air conditioning load 90 together with the cold water that is cooled by the heat radiation of the hydrate slurry in the heat storage tank 85.

FIG. 21 is an explanatory diagram of a heat storage air conditioning system that employs a double evaporator type refrigerator similar to the heat storage air conditioning system 3 of the third embodiment.
Hereinafter, the heat storage air-conditioning system employing the double evaporator type refrigerator will be described in detail with reference to FIG. First, the configuration of a double evaporator type refrigerator (the portion indicated by reference numeral 100 in parentheses in the figure) will be described, and then the entire configuration will be described.

<Basic structure of refrigerator>
In the figure, 101 is a centrifugal compressor, 102 is an electric motor for driving the centrifugal compressor 101, 103 is a condenser, 104 is a full liquid evaporator for producing cold water, 105 is an evaporator for producing hydrate slurry, 106 Is an expansion valve or orifice in the refrigeration cycle for producing cold water, 107 is an expansion valve or orifice in the refrigeration cycle for producing hydrate slurry, 108 is a refrigerant liquid cutoff valve, and 109 is a refrigerant gas cutoff valve. The refrigerant liquid shutoff valves 108, 109 a, and 109 b constitute the refrigeration cycle for producing cold water and the refrigeration cycle for producing hydrate slurry, respectively. This is a refrigerant gas cutoff valve 109.

The solid arrow in the figure indicates the flow direction of the refrigerant when cold water is produced using the cold water producing liquid-filled evaporator 104, and the dotted arrow indicates that the hydrate slurry producing evaporator 105 is used. Then, the flow direction of the refrigerant when producing the hydrate slurry is shown. R134a and R123 are suitable as the refrigerant.
The refrigeration cycle for producing cold water includes a centrifugal compressor 101, an electric motor 102, a condenser 103, a refrigerant liquid shutoff valve 108a, an expansion valve or orifice 106, a full liquid evaporator 104 for producing cold water, a refrigerant gas shutoff valve 109a and the like. Using the refrigerant pipe to be connected, the centrifugal compressor 101, the condenser 103, the refrigerant liquid cutoff valve 108a, the expansion valve or orifice 106, the full liquid evaporator 104 for producing cold water, the refrigerant gas cutoff valve 109a, the centrifugal compressor This is realized by circulating the refrigerant in the order of 101,. In the full liquid evaporator 104 for producing cold water, the fed water is cooled by heat exchange with the refrigerant and sent out as cold water.

  The hydrate slurry production refrigeration cycle includes a centrifugal compressor 101, an electric motor 102, a condenser 103, a refrigerant liquid cutoff valve 108b, an expansion valve or orifice 107, an hydrate slurry production evaporator 105, and a refrigerant gas cutoff valve 109b. And a refrigerant pipe connecting them, the centrifugal compressor 101, the condenser 103, the refrigerant liquid cutoff valve 108b, the expansion valve or orifice 107, the hydrate slurry producing evaporator 105, the refrigerant gas cutoff valve 109b, the centrifugal This is realized by circulating the refrigerant in the order of the compressors 101,. In the hydrate slurry-producing evaporator 105, the fed raw material aqueous solution is cooled by heat exchange with the refrigerant and is sent out as a hydrate slurry.

  The type of the hydrate slurry-producing evaporator 105 is not particularly limited, but is preferably a full liquid type. The hydrate formation temperature varies depending on the concentration of the raw material aqueous solution, and the concentration varies as the clathrate hydrate is generated from the raw material aqueous solution. It is desired that the control of the temperature is easy and the accuracy of the control is high. In this sense, it can be said that a full liquid evaporator having high heat transfer efficiency and high control accuracy of refrigerant temperature (particularly refrigerant evaporation temperature) is suitable as an evaporator for producing hydrate slurry.

  The switching means for both refrigeration cycles include expansion valves or orifices 106 and 107, refrigerant liquid cutoff valves 108 (108a and 108b), refrigerant gas cutoff valves 109 (109a and 109b), and driving devices (K1 to K4) for driving them, and It comprises a control device CTL (not shown) that controls the drive device. By this switching means, the hydrate slurry producing evaporator and the cold water producing full-type evaporator can be selectively connected to the refrigeration cycle, and the hydrate slurry producing refrigeration cycle and the cold water producing refrigeration cycle Thus, a single refrigeration cycle is configured as a whole. And at least the centrifugal compressor 101 and the condenser 103 constituting the single refrigeration cycle, more specifically, the centrifugal compressor 101, the electric motor 102, the condenser 103, and the refrigerant pipe connecting them are hydrates. It is combined between the refrigeration cycle for producing slurry and the refrigeration cycle for producing cold water.

<Operation and operating method of refrigerator>
Next, the operation and operation method of the refrigerator will be described. Either the refrigerant liquid shut-off valve (108a, 108b) or the refrigerant gas shut-off valve (109a, 109b) is sufficient for the purpose of shutting off the refrigerant alone. It shall be.
(1) When producing hydrate slurry using the hydrate slurry producing evaporator 105 First, at least one of the refrigerant liquid cutoff valve 108a and the refrigerant gas cutoff valve 109a is closed by the switching means, and the expansion valve Alternatively, the orifice 106 is closed (inoperable), the cold refrigerant liquid cutoff valve 108b and the refrigerant gas cutoff valve 109b are opened, and the expansion valve or orifice 107 is opened (operable). Thereby, the refrigerant | coolant distribution path | route (path | route along the dotted-line arrow in a figure) in the refrigerating cycle for hydrate slurry manufacture is comprised.

Next, the centrifugal compressor 101 is driven by the electric motor 102 to compress the refrigerant gas. The refrigerant gas compressed by the centrifugal compressor 101 is sent to the condenser 103 where it is cooled by cooling water. This cooling makes the refrigerant almost saturated. Subsequently, the refrigerant liquid is sent to the expansion valve or orifice 107 and depressurized. The decompressed refrigerant liquid is sent to the full liquid evaporator 5 for producing the hydrate slurry, and the raw material aqueous solution flowing through the heat transfer tube in the evaporator 105 for producing the hydrate slurry is cooled to clathrate hydrate. This is made into a hydrate slurry which is dispersed or turbid in the raw material aqueous solution, and evaporates and gasifies itself. The gasified refrigerant is sent again to the centrifugal compressor 101, and the above circulation is repeated thereafter. Therefore, the refrigerant flows only through the hydrate slurry-producing evaporator 105.
As a result, the raw material aqueous solution is cooled in the hydrate slurry-producing evaporator 105 to produce a hydrate slurry.

(2) When producing cold water using the full liquid evaporator 104 for producing cold water First, at least one of the refrigerant liquid cutoff valve 108b and the refrigerant gas cutoff valve 109b is closed by the switching means, and an expansion valve or orifice 107 is closed (inoperable), the refrigerant liquid cutoff valve 108a and the refrigerant gas cutoff valve 109a are all opened, and the expansion valve or orifice 106 is opened (operable). Thus, a refrigerant flow path (path along the solid line arrow in the figure) in the refrigeration cycle for producing cold water is configured.
Next, the centrifugal compressor 101 is driven by the electric motor 102 to compress the refrigerant gas. The refrigerant gas compressed by the centrifugal compressor 101 is sent to the condenser 103 where it is cooled by cooling water. This cooling makes the refrigerant almost saturated. Subsequently, the refrigerant liquid is sent to the expansion valve or orifice 106 and depressurized. The decompressed refrigerant liquid is sent to the full liquid evaporator 104 for producing cold water, and the water flowing through the heat transfer pipe in the cold water producing liquid full evaporator 104 is cooled to cold water, and is evaporated and gasified by itself. To do. The gasified refrigerant is sent again to the centrifugal compressor 101, and the above circulation is repeated thereafter. Therefore, the refrigerant flows only through the full liquid evaporator 104 for producing cold water.
As a result, the water supplied in the full-water evaporator 104 for producing cold water is cooled to produce cold water.

(3) Temperature conditions during production of cold water and hydrate slurry (3-1) Cold water and hydrate slurry produced in the full liquid evaporator 104 for producing cold water and the evaporator 105 for producing hydrate slurry, respectively Each temperature (both outlet temperatures of the evaporators 104 and 105) is set to about 4 to 8 ° C. In the case of chilled water air conditioning equipment, 4 ° C is the lower limit in order to avoid the above-mentioned freezing problem, while the upper limit is generally the temperature required in the cooling load side equipment (air conditioners, AHU, FCU, etc.) Since it is 7-8 degreeC, it will be about 8 degreeC. The same applies to the hydrate slurry air conditioner.

(3-2) If the refrigerant evaporating temperatures of the full-water evaporator 104 for producing cold water and the evaporator 105 for producing hydrate slurry are designed to be the same, the operating conditions of the centrifugal compressor 101 are This can be the same whether or not the refrigeration cycle for producing a hydrate slurry or the refrigeration cycle for producing cold water is constituted.
For example, the refrigerant evaporation temperature and the cold water outlet temperature in the full liquid evaporator 104 for cold water production are 2 ° C. and 5 ° C., respectively, and the refrigerant evaporation temperature and the hydrate slurry outlet temperature in the hydrate slurry production evaporator 105 are set. Is designed to be 2 ° C. and 5 ° C., respectively, since the refrigerant evaporation temperature in both evaporators 104 and 105 is 2 ° C., the operating condition of the centrifugal compressor 101 is that for producing hydrate slurry. It is the same whether it constitutes a refrigeration cycle or a refrigeration cycle for producing cold water.
Therefore, if the design as described above is performed, the compressor 101 is not only used between the refrigeration cycle for producing the hydrate slurry and the refrigeration cycle for producing cold water, but the refrigeration cycle can be switched to any refrigeration cycle. Accordingly, it is not necessary to change the operating conditions of the compressor 101 accordingly.

<Summary>
Therefore, in the refrigerator used in this example, the hydrate slurry-producing evaporator and the cold water-producing full-liquid evaporator can be selectively connected to a single refrigeration cycle by a switching means. The refrigeration cycle for use and the refrigeration cycle for producing hydrate slurry are alternatively switched. Therefore, it can be applied to both hydrate slurry air-conditioning equipment and cold water air-conditioning equipment, and also to air-conditioning equipment that performs night operation to produce hydrate slurry and daytime operation to produce cold water (especially follow-up operation). Single refrigerator. In both refrigeration cycles, at least the centrifugal compressor 101 and the condenser 103 are used in common, and more specifically, the centrifugal compressor 101, the electric motor 102, the condenser 103, and a refrigerant pipe connecting them are also used. Therefore, a relatively low equipment cost or a high cost-effectiveness can be realized.

In addition, although the centrifugal compressor 101 in the drawing is drawn in a single stage, it may be a multistage. And since the multi-stage system is more expensive than the single-stage system, the effect of the present invention, that is, the relative reduction in the equipment cost or the relative increase in cost-effectiveness achieved by the combined use of the compressor, is more than the single-stage system. The compressor of the type becomes more prominent.
In the refrigerator 100 shown in FIG. 21, the functions of the two refrigerant shutoff valves (108a, 108b) can be replaced by one three-way valve arranged at the point P. Further, the functions of the two refrigerant gas shut-off valves (109a, 109b) can be replaced by one three-way valve arranged at the Q point.
Note that each of the expansion valves or orifices 106 and 107 may be provided with a drive device (not shown) so that the opening degree can be controlled by a control device CRL (not shown). As a result, the opening degree of the expansion valve or orifice 106 or 107 can be adjusted according to each refrigeration cycle so that the respective operating conditions are suitable for each refrigeration cycle. For example, the degree of superheat of the refrigerant gas at the outlet of the evaporator is detected, and the opening degree of the expansion valve or orifice 106 or 107 is adjusted so that the degree of superheat becomes a constant value. Further, a liquid level gauge is provided in the evaporator, the liquid level position is detected, and the opening degree of the expansion valve or orifice 106 or 107 is adjusted so that the liquid level position becomes constant.

<Basic configuration of air conditioning equipment>
Next, other components shown in FIG. 21 will be described.
In FIG. 21, 111 is a cooling tower, 112 is a three-way valve, 113 is a buffer tank, 114 is a hydrate slurry heat storage tank, 115 is a cold water / hydrate slurry heat exchanger, and 116 is a heat utilization side load (for example, an air conditioner). ) 117 to 121 are pumps, in particular 117 is a hydrate slurry recirculation pump, 118 is a raw material aqueous solution conveyance pump, 119 is a hydrate slurry removal pump, 120 is a cold water conveyance pump, and 121 is a cooling water conveyance. Pump. 122 is a flow meter, 123 to 127 and 130 to 132 are temperature sensors, and 128 and 129 are open / close valves.
The hydrate slurry heat storage tank 114 is provided with a level meter (not shown) for detecting the amount of hydrate slurry contained.

  The air conditioning equipment shown in FIG. 21 includes the refrigerator 100, the cooling water / water circulation path A between the cooling tower 111 and the condenser 103, the liquid-filled evaporator 104 for producing cold water, and the heat utilization side load 116. Cold water / water circulation path B, hydrate slurry production heat exchanger 5 and hydrate slurry heat storage tank 114 hydrate slurry / raw material aqueous solution circulation path C, hydrate slurry production evaporation The hydrate slurry recirculation path D between the vessel 105 and the buffer tank 113, the hydrate slurry / raw aqueous solution between the hydrate slurry heat storage tank 114 and the cold water / hydrate slurry heat exchanger 115 A circulation path E, a cold water / water circulation path F between the cold water / hydrate slurry heat exchanger 115 and the heat utilization side load 116 is provided.

Route A follows 111, 112, 121, 123, 103, M point, 111,..., And route B follows 104, 124, S point, 116, 120, R point, 129, 104,. It is the route of the piping that goes around. Route C follows 105, 113, 126, 114, 118, N points, 122, 105, 130, 113... Route D follows 105, 113, 117, N points, 122, 105,. It is the route of the piping that goes around. The route E is 114, 119, 115, 114,..., And the route F is a piping route that goes around 115, 127, S point, 116, 120, R point, 115,.
Production of chilled water by path A, refrigerator, and path B and heat utilization at the heat utilization side load of the thermal energy of the chilled water are performed. Production of hydrate slurry by path A, refrigerator, path C, and path D Accumulation is performed, and heat utilization at the heat utilization side load of the thermal energy of the accumulated hydrate slurry is performed by the path E and the path F.

(1) Route A In route A, the cooling water sent from the cooling tower 111 is conveyed by the pump 121, passes through the three-way valve 112, the pump 121, and the temperature sensor 123, and is supplied to the condenser 103. In 103, it is subjected to heat exchange for condensing the refrigerant gas, and then returns to the cooling tower 111 as water whose temperature has risen. Thereafter, this circulation is repeated.
The temperature control of the cooling water is performed by the operation of the three-way valve 112 based on the output of the temperature sensor 123 that measures the temperature of the cooling water supplied to the condenser 103. That is, when the temperature of the cooling water is lower than the target value, the driving amount of the three-way valve 112 corresponding to the deviation is calculated in the TIC, and the three-way valve 112 is driven by the calculated value, and relative to the M point. The hot water is taken in and mixed with the cooling water to raise the temperature of the cooling water. When the temperature of the cooling water is higher than the target value, the three-way valve 112 is operated so that relatively high temperature water is not taken in from the point M, and the temperature of the cooling water is lowered.

(2) Route B Route B is a route when the refrigerator 100 constitutes a refrigeration cycle for producing cold water. In the path B, the cold water delivered from the liquid-filled evaporator 104 for producing cold water is transported by the pump 120 and is used for heat in the heat utilization side load 116, and then the pump 120, R point as water whose water temperature has risen. Then, it returns to the liquid-filled evaporator 104 for producing cold water through the open / close valve 129. Thereafter, this circulation is repeated.
The temperature control of the chilled water is based on the output of the temperature sensor 124 that measures the temperature of the chilled water sent from the liquid-filled evaporator 104 for producing chilled water. This is done by changing. That is, when the temperature of the cold water is lower than the target value and the output of the temperature sensor 124 is less than the set value, the output change amount of the electric motor 102 corresponding to the deviation is calculated in the TIC, and the electric motor is calculated by the calculated value. 102, and hence the rotation speed of the compressor 101 is decreased, the refrigerant evaporation temperature in the liquid-filled evaporator 104 for cold water production is increased, and the outlet temperature of the cold water is increased. On the other hand, when the temperature of the cold water is higher than the target value and the output of the temperature sensor 124 exceeds the set value, the output change amount of the motor 102 corresponding to the deviation is calculated in the TIC, and only the calculated value is calculated. The rotation speed of the electric motor 102, and hence the compressor 101, is increased, the refrigerant evaporation temperature in the liquid-filled evaporator 104 for cold water production is lowered, and the outlet temperature of the cold water is lowered. The above control is performed so that the deviation between the output of the temperature sensor 124 and the set value becomes zero.

(3) About the path | route C and the path | route D Both the path | route C and the path | route D are paths when the refrigerator 100 comprises the refrigeration cycle for hydrate slurry manufacture. The path D is a path for joining the hydrate slurry from the buffer tank 113 to the path C in order to control the flow rate of the raw material aqueous solution conveyed to the hydrate slurry-producing evaporator 105.
(3-1)
In the path C, the raw material aqueous solution previously stored in the hydrate slurry heat storage tank 114 is transported by the pump 118 and merged with the hydrate slurry transported from the buffer tank 113 by the pump 117 at the point N. It reaches the Japanese slurry producing evaporator 105 and is used for heat exchange with the refrigerant liquid in the hydrate slurry producing evaporator 105. Here, the raw material aqueous solution is cooled to produce a hydrate slurry. That is, clathrate hydrate is generated from the cooled raw material aqueous solution, and the generated hydrate is dispersed or suspended in the raw aqueous solution to form a hydrate slurry. The hydrate slurry is sent from the hydrate slurry-producing evaporator 105, a part of which is stored in the buffer tank 113, and the remainder is sent to the hydrate slurry heat storage tank 114 where it is stored. By repeating the circulation of the raw material aqueous solution / hydrate slurry between the hydrate slurry-producing evaporator 105 and the hydrate slurry heat storage tank 114, the buffer tank 113 and the hydrate slurry heat storage tank 114 are repeated. The solid phase ratio of the hydrate slurry stored in the tank, and hence the heat storage amount, gradually increases.

The temperature control of the hydrate slurry is performed by at least one of the following methods (a) and (b).
(A) The inverter control of the electric motor 102 is performed based on the output of the temperature sensor 126 that measures the temperature of the hydrate slurry sent to the hydrate slurry heat storage tank 114, and the rotation speed of the compressor 101 is changed by a necessary amount. . That is, when the temperature of the hydrate slurry is lower than the target value, and therefore the output of the temperature sensor 126 is less than the set value, the output change amount of the motor 102 corresponding to the deviation is calculated in the TIC, and the calculation is performed. The number of rotations of the electric motor 102 and therefore the compressor 101 is decreased by the value, the refrigerant evaporation temperature in the evaporator 105 for producing the hydrate slurry is increased, and the outlet temperature of the hydrate slurry, and further, the hydrate slurry from the buffer tank 113 is increased. The temperature of the hydrate slurry toward the heat storage tank 114 is increased. When the temperature of the hydrate slurry is higher than the target value and the output of the temperature sensor 126 exceeds the set value, the output change amount of the motor 102 corresponding to the deviation is calculated in the TIC, and the calculated value Only the motor 102 and therefore the compressor 101 is rotated at a higher speed, the refrigerant evaporation temperature in the hydrate slurry-producing evaporator 105 is lowered, and the hydrate slurry outlet temperature, and thus the hydrate slurry heat storage from the buffer tank 113. The temperature of the hydrate slurry toward tank 114 is reduced. The above control is performed so that the deviation between the output of the temperature sensor 126 and the set value becomes zero.

    (A) The inverter control of the pump 118 is performed based on the output of the temperature sensor 126, and the supply amount of the raw material aqueous solution (including the hydrate slurry as the raw material aqueous solution) to the hydrate slurry manufacturing evaporator 105 is as much as necessary. This is done by changing. That is, when the temperature of the hydrate slurry is lower than the target value and the output of the temperature sensor 126 is less than the set value, the output change amount of the pump 118 corresponding to the deviation is calculated in the TIC, and the calculation is performed. The output of the pump 118 is increased by the value to increase the supply amount of the raw material aqueous solution to the hydrate slurry-producing evaporator 105 so that the outlet temperature of the hydrate slurry increases. When the temperature of the hydrate slurry is higher than the target value and the output of the temperature sensor 126 exceeds the set value, the output change amount of the pump 118 corresponding to the deviation is calculated in the TIC, and the calculated value Only the output of the pump 118 is reduced, the supply amount of the raw material aqueous solution to the evaporator 105 for producing the hydrate slurry is lowered, and the outlet temperature of the hydrate slurry is lowered. The above control is performed so that the deviation between the output of the temperature sensor 126 and the set value becomes zero.

(3-2)
Among the hydrate slurries sent from the hydrate slurry-producing evaporator 105 in the path D, the one stored in the buffer tank 113 is transported by the pump 117 and is transported by the pump 118 at the point N. After merging with (including the hydrate slurry as the raw material aqueous solution), it reaches the hydrate slurry producing evaporator 105 and is used for heat exchange with the refrigerant liquid in the hydrate slurry producing evaporator 105. .
Here, the raw material aqueous solution is cooled to produce a hydrate slurry. That is, clathrate hydrate is generated from the cooled raw material aqueous solution, and the generated hydrate is dispersed or suspended in the raw aqueous solution to form a hydrate slurry. The hydrate slurry is sent from the hydrate slurry-producing evaporator 105, a part of which is stored in the buffer tank 113, and the remainder is sent to the hydrate slurry heat storage tank 114. Hydration stored in the buffer tank 113 and the hydrate slurry heat storage tank 114 by repeating the circulation of the hydrate slurry between the evaporator 105 for producing the hydrate slurry and the buffer tank 113 is repeated. The solid phase fraction of the material slurry, and hence the heat storage amount, gradually increases.

When the hydrate slurry-producing evaporator 105 is a full liquid evaporator, a part of the hydrate adhering to the inner wall surface of the heat transfer tube is removed from the raw material aqueous solution (or the hydrate slurry as the raw material aqueous solution). It is desirable to produce the hydrate slurry by removing it by the force of the flow and leaving the remainder so as to cover the inner wall surface of the heat transfer tube.
At that time, the flow rate is controlled in order to control the flow rate of the raw material aqueous solution flowing inside the heat transfer tube to a constant speed equal to or higher than a predetermined value. The flow rate control of the raw material aqueous solution (including the hydrate slurry as the raw material aqueous solution) supplied to the hydrate slurry manufacturing evaporator 105 is controlled by the flow rate of the raw material aqueous solution supplied to the hydrate slurry manufacturing evaporator 105. Based on the output of the flow meter 122 to be measured, inverter control of the pump 117 is performed, and the amount of hydrate slurry delivered from the buffer tank 113 to the point N is changed by a necessary amount. That is, when the flow rate of the raw material aqueous solution is lower than the target value and the output of the flow meter 122 is less than the set value, the output change amount of the pump 117 corresponding to the deviation is calculated in the FIC, and only the calculated value is calculated. The output of the pump 117 is increased, the amount of hydrate slurry delivered from the buffer tank 113 to the N point is increased, and the flow rate of the raw material aqueous solution from the N point toward the hydrate slurry-producing evaporator 105 is increased. . On the other hand, when the flow rate of the raw material aqueous solution is higher than the target value and the output of the flow meter 122 exceeds the set value, the output change amount of the pump 117 corresponding to the deviation is calculated in the FIC, and the calculated value Only the output of the pump 117 is reduced, the amount of hydrate slurry delivered from the buffer tank 113 to the N point is reduced, and the flow rate of the raw material aqueous solution from the N point toward the hydrate slurry producing evaporator 105 is reduced. To do. The above control is performed so that the deviation between the output of the flow meter 122 and the set value becomes zero.

(3-3)
Control of the refrigerant evaporation temperature in the hydrate slurry-producing evaporator 105 is performed so that the fluctuation range is small.
Specifically, inverter control of the electric motor 102 is performed based on the output of the temperature sensor 125 that measures the refrigerant temperature in the hydrate slurry-producing evaporator 105, and the rotational speed of the compressor 101 is changed by a necessary amount. That is, when the refrigerant evaporation temperature is lower than the target value, and therefore the output of the temperature sensor 125 is less than the set value, the output change amount of the electric motor 102 corresponding to the deviation is calculated in the TIC, and the electric motor is calculated by the calculated value. 102, and hence the rotational speed of the compressor 101 is decreased, and the refrigerant evaporation temperature in the hydrate slurry-producing evaporator 105 is increased.
When the refrigerant evaporation temperature is higher than the target value and the output of the temperature sensor 125 exceeds the set value, the output change amount of the electric motor 102 corresponding to the deviation is calculated in the TIC, and the electric motor 102 is calculated by the calculated value. Therefore, the rotational speed of the compressor 101 is increased, and the refrigerant evaporation temperature in the hydrate slurry-producing evaporator 105 is decreased.
The above control is performed so that the deviation between the output of the temperature sensor 125 and the set value becomes zero. 125 may be a pressure sensor that measures the pressure of the refrigerant gas instead of the temperature sensor. The target value and the set value may be plural (for example, an upper limit value and a lower limit value).

(3-4)
In the case of producing a hydrate slurry, this is first started in the route D. When the production of the hydrate slurry is started, the raw material aqueous solution is stored in the buffer tank 113, and the pump 117 is activated to send the raw material aqueous solution to the hydrate slurry producing evaporator 105, and the refrigerant liquid and heat. Replace and cool. In the buffer tank 113, by adding a hydrate slurry produced separately or by providing a means for releasing the supercooling of the raw material aqueous solution such as a cooling means, the supercooling is released and a hydrate is generated to produce a hydrate slurry. Is manufactured. In addition, the outlet temperature of the hydrate slurry in the hydrate slurry-producing evaporator 105 and the temperature of the hydrate slurry in the buffer tank 113 are measured and monitored by temperature sensors 130 and 131, respectively. When the output of the temperature sensor 130 or 131 reaches a predetermined value, the pump 118 is started by manual operation by an operator or by a control signal (g7) from the control device CTL, and the path C is superimposed.

  The raw material aqueous solution previously stored in the hydrate slurry heat storage tank 114 is transported by the pump 118 and merged with the hydrate slurry transported from the buffer tank 113 at the point N, and then the evaporator for producing the hydrate slurry. At 105, the hydrate slurry producing evaporator 105 is used for heat exchange with the refrigerant liquid, and the raw material aqueous solution is cooled to produce a hydrate slurry. The hydrate slurry is sent from the hydrate slurry-producing evaporator 105, a part of which is stored in the buffer tank 113, and the remainder is sent to the hydrate slurry heat storage tank 114 where it is stored. In order to control the flow rate of the raw material aqueous solution flowing inside the heat transfer tube of the evaporator 105 for producing hydrate slurry to a constant speed equal to or higher than a predetermined value, inverter control of the pump 117 is performed based on the output of the flow meter 122, and the buffer tank The flow rate of the hydrate slurry from 113 to the hydrate slurry-producing evaporator 105 is controlled. When the hydrate slurry is produced, the route D is a hydrate slurry recirculation route for controlling the flow rate of the raw material aqueous solution conveyed to the hydrate slurry producing evaporator 105. Further, the pump 118 is controlled so that the output of the temperature sensor 126 for measuring the temperature of the hydrate slurry sent to the hydrate slurry heat storage tank 114 becomes a set value (the above (3-1) (i). reference).

(4) About the path | route E and the path | route F The path | route E and the path | route F are paths for using the thermal energy (cold heat) which the hydrate slurry stored in the hydrate slurry heat storage tank 114 has for heat utilization.
In the path E, the hydrate slurry stored in the hydrate slurry heat storage tank 114 is transported by the pump 119 and supplied to the cold water / hydrate slurry heat exchanger 115 to exchange cold water / hydrate slurry heat. It is subjected to heat exchange for converting the water into cold water in the vessel 115, and then returns to the hydrate slurry heat storage tank 114 in the state of an aqueous solution. Thereafter, this circulation is repeated. In the path F, the cold water produced by heat exchange with the hydrate slurry in the cold water / hydrate slurry heat exchanger 115 is transported by the pump 120 and used for heat in the heat utilization side load 116, and then the water temperature. Is returned to the chilled water / hydrate slurry heat exchanger 115 through the pump 120, the R point, and the open / close valve 128. Thereafter, this circulation is repeated. Therefore, the path E and the path F are connected to each other through the cold water / hydrate slurry heat exchanger 115 in a heat transfer manner, so that the thermal energy equivalent to the latent heat of the hydrate slurry is equivalent to the sensible heat of the cold water. And is supplied to the heat utilization side load 116.

  Control of the outlet temperature of the chilled water in the chilled water / hydrate slurry heat exchanger 115 is based on the output of the temperature sensor 127 that measures the temperature of the chilled water sent from the chilled water / hydrate slurry heat exchanger 115, and the inverter of the pump 119. Control is performed by changing the supply amount of the hydrate slurry to the cold water / hydrate slurry heat exchanger 115 by a necessary amount. That is, when the temperature of the cold water is lower than the target value and the output of the temperature sensor 127 is less than the set value, the output change amount of the pump 119 corresponding to the deviation is calculated in the TIC, and only the calculated value is the pump. The output of 119 is decreased, the supply amount of the hydrate slurry to the cold water / hydrate slurry heat exchanger 115 is decreased, and the outlet temperature of the cold water is increased. On the other hand, when the temperature of the cold water is higher than the target value and the output of the temperature sensor 127 exceeds the set value, the output change amount of the pump 119 corresponding to the deviation is calculated in the TIC, and only the calculated value is calculated. The output of the pump 119 is increased, the supply amount of the hydrate slurry to the cold water / hydrate slurry heat exchanger 115 is increased, and the outlet temperature of the cold water is decreased. The above control is performed so that the deviation between the output of the temperature sensor 127 and the set value becomes zero.

<Operation and operation mode of air conditioning equipment>
The entire operation of the air conditioning equipment shown in FIG. 21 is controlled by the control device CTL including the operation of the refrigerator. The operation mode of the air conditioning equipment includes at least the following operation modes (M1) to (M4).

(M1) An operation mode in which cold water produced in the liquid-filled evaporator 104 for producing cold water is supplied to the heat utilization side load 116 (that is, an operation mode using the refrigerator and the path B).
In this operation mode, the control device CTL transmits the control signals g1 to g4 to operate the drive devices (K1 to K4) of the refrigerant shutoff valves 108a and 108b and the refrigerant gas shutoff valves 109a and 109b, and the shutoff valves. 108a and 109a are opened and shut-off valves 108b and 109b are closed, whereby a refrigeration cycle for producing cold water is configured in the refrigerator. At the same time, the control device CTL transmits control signals g5 and g6 to operate the driving devices (K5 and K6) of the on-off valves 128 and 129, close the valve 128, open the valve 129, and thereby the heat utilization side load 116. Is connected to the route B and is not connected to the route F. As described above, the refrigerator and the path B are connected via the liquid-filled evaporator 104 for producing cold water, and only the cold water produced in the liquid-filled evaporator 104 for producing cold water is supplied to the heat utilization side load 116. It becomes like this.

(M2) An operation mode in which the hydrate slurry produced in the hydrate slurry production evaporator 105 is supplied to the hydrate slurry heat storage tank 114 (that is, operation using the refrigerator, the path C, and the path D). mode)
In this operation mode, the control device CTL transmits control signals g1 to g4, operates the driving devices (K1 to K4), closes the shut-off valves 108a and 109a, and opens the shut-off valves 108b and 109b. A refrigeration cycle for producing a hydrate slurry is configured. As a result, the refrigerator and the path C and the path D are connected via the hydrate slurry-producing evaporator 105, and the hydrate slurry produced in the liquid-filled evaporator 104 for producing cold water is hydrate slurry. The heat storage tank 114 is supplied.

(M3) An operation mode in which heat energy of the hydrate slurry stored in the hydrate slurry heat storage tank 114 is supplied to the heat utilization side load 116 (that is, an operation mode using the path E and the path F).
In this operation mode, the control device CTL transmits control signals g5 and g6 to operate the driving devices (K5 and K6) of the on-off valves 128 and 129, open the valve 128, close the valve 129, and thereby heat The use side load 116 is disconnected from the path B and connected to the path F. Thereby, the heat utilization side load 116 and the hydrate slurry heat storage tank 114 are connected via the path E, the cold water / hydrate slurry heat exchanger 115 and the path F, and are stored in the hydrate slurry heat storage tank 114. Use of heat energy equivalent to latent heat of the hydrate slurry as heat energy equivalent to sensible heat of water cooled through heat exchange between the hydrate slurry and water in the cold water / hydrate slurry heat exchanger 115 It is supplied to the side load 116.

(M4) Other operation modes: Before the hydrate slurry produced in the hydrate slurry production evaporator 105 is sufficiently stored in the hydrate slurry heat storage tank 114, the thermal energy of the hydrate slurry is heated. Operation mode for supplying to the use side load 116 (that is, operation mode using the route E and the route F simultaneously with the refrigerator, the route C and the route D)
In this operation mode, the control device CTL transmits control signals g1 to g4, operates the driving devices (K1 to K4), closes the shut-off valves 108a and 109a, and opens the shut-off valves 108b and 109b. A refrigeration cycle for producing a hydrate slurry is configured. At the same time, the control device CTL transmits control signals g5 and g6 to operate the driving devices (K5 and K6) of the on-off valves 128 and 129, open the valve 128, close the valve 129, and thereby the heat utilization side load 116. Is not connected to the route B and connected to the route F.

  As described above, the refrigerator and the path C and the path D are connected via the hydrate slurry-producing evaporator 105, and the hydrate slurry produced in the liquid-filled evaporator 104 for producing cold water is the hydrate slurry. While being supplied to the heat storage tank 114, the heat utilization side load 116 and the hydrate slurry heat storage tank 114 are connected via the path E, the cold water / hydrate slurry heat exchanger 115 and the path F, and the hydrate slurry. Heat energy equivalent to latent heat of the hydrate slurry stored in the heat storage tank 114 is equivalent to sensible heat of water cooled through heat exchange between the hydrate slurry and water in the cold water / hydrate slurry heat exchanger 115. It is supplied to the heat utilization side load 116 as the heat energy.

<Specific examples of how to operate air conditioning equipment>
(1) Nighttime heat storage operation A hydrate slurry is produced and stored in a heat storage tank, that is, a heat storage operation is performed at night. When performing a heat storage operation in the air conditioning facility shown in FIG. 21, first, the hydrate slurry producing evaporator 105 is connected to the refrigeration system instead of the chilled water producing liquid-filled evaporator 104 in the refrigerator 100 to hydrate. The product manufacturing refrigeration system is configured, and the air conditioning equipment is operated in the operation mode (M2). In this case, control is performed so that the fluctuation range of the refrigerant evaporation temperature in the hydrate slurry-producing evaporator 105 is reduced. Specifically, inverter control of the electric motor 102 is performed so that the deviation between the output of the temperature sensor 125 that measures the temperature of the refrigerant liquid in the hydrate slurry-producing evaporator 105 and the set value becomes zero, and the compressor 101 Change the number of revolutions by the required amount.

  When the hydrate slurry-producing evaporator 105 is a full liquid evaporator, a part of the hydrate adhering to the inner wall surface of the heat transfer tube is removed from the raw material aqueous solution (or the hydrate slurry as the raw material aqueous solution). A hydrate slurry is produced by removing it by the force of the flow and leaving the remainder so as to cover the inner wall surface of the heat transfer tube. In that case, it is important that the flow rate of the raw material aqueous solution flowing inside the heat transfer tube is controlled to be constant and the refrigerant evaporation temperature in the full liquid evaporator is not excessively lowered. Therefore, the hydrate slurry is adjusted so that the flow rate of the raw material aqueous solution from the point N toward the hydrate slurry-producing evaporator 105 becomes a target value or the deviation between the output of the flow meter 122 and the set value becomes zero. Inverter control of the pump 117 to be recirculated is performed, and the amount of hydrate slurry delivered from the buffer tank 113 to the point N is changed by a necessary amount (<basic configuration of air conditioning equipment> (3-2) (3-4) reference). At the same time, inverter control of the motor 102 is performed so that the deviation between the output of the temperature sensor 125 for measuring the temperature of the refrigerant liquid in the hydrate slurry-producing evaporator 105 and the set value becomes zero, and the rotation speed of the compressor 101 Is changed by the necessary amount (see <Basic configuration of air conditioning equipment> (3-3)).

Depending on how to set the set value, it is possible to control the electric motor 102 so that the output of the temperature sensor 125 does not become a predetermined value or less, and to change the rotation speed of the compressor 101 by a necessary amount. It can be employed in the heat storage operation of the air conditioning equipment shown in FIG. 21 (whether or not the hydrate slurry-producing evaporator 105 is a full-liquid evaporator).
When producing the hydrate slurry, first, this is started in the route D, and the outlet temperature of the hydrate slurry in the hydrate slurry producing evaporator 105 or the hydrate slurry in the buffer tank 113 is started. When the temperature reaches a predetermined value, the pump 118 is started, the path C is superimposed, and the pump 118 is controlled so that the inlet temperature of the hydrate slurry in the hydrate slurry heat storage tank 114 becomes a set value ( <Basic configuration of air conditioning equipment> (Refer to 3-4)).
When the hydrate slurry heat storage tank 114 is filled with the hydrate slurry or when the heat storage time is over, the centrifugal compressor 101 and the electric motor 102 are stopped, and the pump 118 and the pump 117 are manually operated in this order. Alternatively, it is stopped by a control signal from the control device CTL.

During the heat storage operation, the amount of hydrate adhering to the inner wall surface of the heat transfer tube of the evaporator 105 for producing the hydrate slurry increases and accumulates, increasing the pressure loss in the heat transfer tube and hindering the production of the hydrate slurry. If this occurs, a melting operation that melts and removes the attached hydrate is necessary.
For the melting operation, a bypass path for bypassing the compressor 101 of the refrigerator and communicating the hydrate slurry-producing evaporator 105 and the condenser 103 and a bypass valve for opening and closing the bypass path may be provided. By providing such a bypass valve, during the melting operation, the compressor 101 and the electric motor 102 are stopped, the bypass valve is opened, and the hydrate slurry producing evaporator 105 and the condenser 103 are bypassed by the compressor 101. Communicate. As a result, the high-temperature and high-pressure refrigerant in the condenser 103 circulates in the hydrate slurry-producing evaporator 105 via the bypass path, and the heat and heat held by the high-temperature and high-pressure refrigerant in the condenser 103 enter the heat transfer tube. The adhering hydrate can be melted away.

(2) Daytime operation (2-1) Heat storage use operation Heat of the hydrate slurry stored in the hydrate slurry heat storage tank 114 for cooling the heat use side load 116 side, that is, air conditioning operation. We use energy (cold heat) in the daytime. When the heat storage operation is performed in the air conditioner shown in FIG. 21, the air conditioner is operated in the operation mode (M3). In this case, the pump 119 is controlled so that the outlet temperature of the chilled water in the chilled water / hydrate slurry heat exchanger 115 becomes a target value (<Basic configuration of air conditioning equipment> (4)).

(2-2) Refrigerator follow-up operation In order to cover the cooling heat necessary for cooling the heat utilization side load 116 side, only the cooling heat of the hydrate slurry stored in the hydrate slurry heat storage tank 114 is used. Then, when there is a deficiency, the air-conditioning operation is to make up for the deficiency by cooling the cold water produced separately.
For example, in the refrigerator according to the present invention, not the hydrate slurry-producing evaporator 105 but the cold-water producing liquid-filled evaporator 104 is connected to the refrigeration system to constitute the chilled water producing refrigeration system, and the above (M1) The air conditioning equipment is operated in the operation mode. At this time, the temperature sensor 124 provided on the outlet side of the liquid-filled evaporator 104 for producing cold water measures the outlet temperature of the cold water and controls the rotational speed of the centrifugal compressor 101 so that the outlet temperature becomes constant. To do. Then, the on-off valve 128 is opened, and the cold water from the cold water / hydrate slurry heat exchanger 115 and the cold water from the liquid-filled evaporator 104 for producing cold water are conveyed to the heat utilization side load 116. Thereby, the cold energy which both cold water has is supplied to the heat utilization side load 116.
As another example, first, the cold energy of the hydrate slurry stored in the hydrate slurry heat storage tank 114 is exchanged into cold water by the cold water / hydrate slurry heat exchanger 115 to cool the cold water. Energy is supplied to the heat utilization side load 116 so that it is used up as much as possible (it is not necessary to use up). Thereafter, the air conditioning equipment is operated in the operation mode (M1), and the cold energy of the cold water produced in the liquid-filled evaporator 104 for producing cold water is supplied to the heat utilization side load 116.
The follow-up operation can be realized by any of the above two examples.

  Next, examples of turbulence forming means for forming turbulence in the flow of the raw material solution or raw material slurry in the heat transfer tube provided in the hydrate slurry manufacturing apparatus of the present invention will be shown in the following examples.

FIG. 22 is a view showing a twisted tape as an example of the turbulence forming means. The twisted tape is inserted into the heat transfer tube, and the twisted tape is used to swirl the flow of the raw material solution or raw material slurry, thereby creating turbulence and stirring the boundary layer near the inner wall surface of the heat transfer tube to promote convective heat transfer The heat transfer efficiency from the refrigerant to the raw material solution or the raw material slurry can be improved.
The twisted tape may be inserted into a part of the heat transfer tube inlet or the like, or may be inserted into the entire heat transfer tube.

FIG. 23 is a view showing another example of the turbulence forming means in which protrusions (turbulence promoters) are arranged on the inner surface of the heat transfer tube. The protrusions cause a disturbance in the flow of the raw material solution or slurry inside the heat transfer tube and disturb the boundary layer near the inner wall surface of the heat transfer tube to promote convective heat transfer and transfer from the refrigerant to the raw material solution or slurry. Thermal efficiency can be improved.
Regardless of the shape of projections (cylindrical, rectangular, conical, flat plate), dimensions (height, width), mounting form (upright, inclined), arrangement interval and arrangement shape (on grid, staggered, etc.) Just choose one. Moreover, you may insert in one part, such as a heat exchanger tube inlet_port | entrance part, and may insert in all the inside of a heat exchanger tube.

By providing the turbulence forming means inside the heat transfer tube, turbulence can be formed in the flow of the raw material solution or raw material slurry supplied to the inside of the heat transfer tube, and the clathrate hydrate adhering to the inner wall surface of the heat transfer tube Therefore, the clathrate hydrate slurry can be stably produced over a long period of time or continuously.
In addition, since the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube can be reduced, the heat resistance due to the clathrate hydrate adhering to it decreases, and the heat transfer efficiency from the refrigerant to the raw material solution or slurry Improves and the amount of heat transfer increases. This leads to a reduction in the heat transfer area (the number of heat transfer tubes).
Also, because the flow of the raw material solution or raw material slurry inside the heat transfer tube is disturbed, the efficiency of heat transfer from the refrigerant to the raw material solution or raw material slurry is improved, so that the production capacity of clathrate hydrate slurry is improved. Can do.
Even if the flow rate of the raw material solution or raw material slurry flowing inside the heat transfer tube is reduced as compared with the case where no turbulence forming means is provided, the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube is increased. It can suppress by the force of a flow and can maintain the heat exchange efficiency of a heat exchanger tube. Thereby, the load concerning the pump apparatus for flowing a raw material solution or a raw material slurry can be reduced relatively.

  Next, in the hydrate slurry production apparatus of the present invention, an example in which irregularities are formed along the direction in which the aqueous solution or the slurry flows on at least one of the inner wall surface and the outer wall surface of the heat transfer tube is as follows. Shown in the example.

FIG. 24 is a view showing a corrugated pipe as an example of a pipe provided with irregularities on the inner wall surface and the outer wall surface thereof. A narrow convex portion is formed into a spiral shape on the inner wall surface of the heat transfer tube, and a concave portion is formed between the convex portions along the direction in which the raw material solution or the raw material slurry flows.
FIG. 25 is a view showing an internally grooved tube (fluted tube) as an example of a tube in which unevenness is provided on the inner wall surface of the heat transfer tube. A groove with a depth of 0.4 mm is spirally provided on the inner wall of the heat transfer tube with a twist angle of 50 degrees.

Using the double-tube single-tube experiment apparatus shown in FIG. 4, it was examined how the heat transfer performance and the pressure loss change depending on the shape of the inner wall surface of the heat transfer tube. The heat transfer tubes used for the test were an inner smooth tube (inner diameter 16.2mm) with no irregularities on the inner surface, an inner grooved tube (groove depth 0.4mm, number of grooves 34 / inch, Hitachi Cable Model No. TE-iE), corrugated tube (Inner surface convex part height 0.6mm, convex part pitch 14mm, Hitachi Cable make model number JISH3300). The results are shown in FIGS. 26 and 27. FIG. 26 shows the relationship between the in-tube flow velocity and the heat passing rate, and FIG. 27 shows the relationship between the in-tube flow velocity and the slurry differential pressure at the heat transfer tube inlet and outlet measured as pressure loss. Show.
As shown in FIG. 26, the heat passage rate is 14 to 32% larger in the inner grooved tube indicated by Δ and the corrugated tube indicated by × than the inner smooth tube indicated by ○. The reason is that the inner grooved tube and the corrugated tube have a spiral formed on the inner wall surface of the heat transfer tube, so that the flow of the raw material solution or raw material slurry is swirled to cause turbulence, and the heat transfer tube By stirring the boundary layer in the vicinity of the wall surface, convective heat transfer can be promoted and the heat transfer efficiency from the refrigerant to the raw material solution or raw material slurry can be improved, and the flow of the raw material solution or raw material slurry is swirled. In order to increase the contact area with the inner wall surface of the heat transfer tube, that is, the heat transfer area, it is estimated that the heat transfer efficiency can be further improved.
In addition, if there is a recess on the inner wall surface of the heat transfer tube, the clathrate hydrate generated in the recess will remain attached, and the remaining clathrate hydrate will function as a generation nucleus, and a new clathrate hydrate Can be generated more easily.
Therefore, from the viewpoint of improving the heat transfer performance of the heat exchanger and facilitating the generation of clathrate hydrate, it can be said that the inner surface grooved tube and the corrugated tube are preferable to the inner surface smooth tube.

  On the other hand, as shown in FIG. 27, the pressure loss (slurry differential pressure) is 30 to 88% larger in the inner grooved tube indicated by Δ and the corrugated tube indicated by × than the inner smooth tube indicated by ○. ing. The increase in pressure loss of the heat transfer tube increases the power of the pump that feeds the raw material solution or raw material slurry, and increases energy consumption. Therefore, it can be said that the inner surface smooth tube is preferable to the inner surface grooved tube and the corrugated tube from the viewpoint of suppressing an increase in pump power or saving energy.

  Therefore, when selecting the shape of the inner wall surface of the heat transfer tube, it is important to select an appropriate shape of the inner wall surface of the heat transfer tube in consideration of both the effect of improving the heat transfer performance as a heat exchanger and the increase in pump power. You can say that.

FIG. 28 is a view showing another example of the heat transfer tube having the outer wall surface provided with irregularities. There are low fin tubes with low fins attached to the outer wall surface of the heat transfer tube at short intervals, heat transfer tubes in which minute cavities, grooves, tunnel structures, or minute protrusions are provided on the outer wall surface by machining or forming. By using a heat transfer tube with irregularities on such an outer wall surface, the heat transfer area of the heat transfer tube is increased and the heat transfer performance is improved, so the heat transfer efficiency from the refrigerant to the raw material solution or the raw slurry is improved. The production capacity of the clathrate hydrate slurry can be improved. In addition, high heat transfer efficiency means that the clathrate hydrate slurry can be produced even if the temperature of the refrigerant is set high, so a heat transfer tube with irregularities on the outer wall surface is used. For example, the load of the refrigerant refrigeration system can be relatively reduced, or the coefficient of performance of the refrigerator can be improved.
An example of the cavity processing tube is “Thermo Excel” (model number TE-E) manufactured by Hitachi Cable. This is a microscopic opening formed on the outer surface and a spiral tunnel connecting them under the outer surface, and bubbles generated by heat exchange of the liquid refrigerant are generated continuously and efficiently. Therefore, it is a heat transfer tube that can obtain extremely high evaporation heat transfer performance. Among heat transfer tubes with irregularities on the outer wall, the cavity processed tube has a heat transfer rate about 10 times higher than that of the low fin tube, and the heat transfer performance is significantly improved compared to smooth tubes without irregularities on the outer wall. . The cavity processed tube is suitable as a heat transfer tube that improves the production capacity of the clathrate hydrate slurry or relatively reduces the load of the refrigerant refrigeration system.

As described above, the heat transfer tube having irregularities on the outer wall surface has high heat transfer efficiency, so even if the flow rate of the raw material solution or raw material slurry flowing through the inside is further increased, the heat exchange efficiency with the raw material solution or raw material slurry is high. Can be maintained. This means that if the outer wall surface of the heat transfer tube is provided with irregularities, the heat exchange efficiency of the heat transfer tube can be maintained high without providing irregularities on the inner wall surface of the heat transfer tube. ing. Therefore, if a heat transfer tube having a smooth inner wall surface and irregularities on the outer wall surface is employed, an increase in pump power can be suppressed, and at the same time, heat exchange efficiency can be maintained high.
Heat transfer tubes with a smooth inner wall surface and irregularities on the outer wall surface are basically hard to attach clathrate hydrates to the inner wall surface, and even if attached, they are easily peeled off due to the flow force of the raw material solution or raw material slurry. In order to suppress the increase of clathrate hydrate adhering to the inner wall surface, and to stably produce clathrate hydrate slurry over a long period of time or continuously, or a refrigerant refrigeration system It is more suitable as a heat transfer tube that relatively reduces the load.

It is a conceptual explanatory drawing which showed the clathrate hydrate production | generation condition for demonstrating the principle of this invention. It is sectional drawing of the pipe orthogonal direction of FIG. It is an enlarged view of the A section enclosed with the circle of FIG. It is explanatory drawing of the experimental apparatus for demonstrating the principle of this invention. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is explanatory drawing of the experimental apparatus for demonstrating the principle of this invention. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is a graph which shows the experimental result by the experimental apparatus shown in FIG. It is explanatory drawing of the apparatus structure of Embodiment 1 of this invention. It is a graph which shows the relationship between the temperature of the hydrate slurry of TBAB aqueous solution, and a solid-phase fraction. FIG. 3 is an explanatory diagram of a device configuration of Example 1. It is explanatory drawing of the apparatus structure of Example 2. FIG. It is explanatory drawing of the apparatus structure of Example 3. FIG. It is explanatory drawing of the apparatus structure of Example 3. FIG. It is explanatory drawing of the disturbance formation means of Example 4. It is explanatory drawing of the other disturbance formation means of Example 4. It is explanatory drawing of the corrugated pipe | tube as an example of the pipe | tube which provided the unevenness | corrugation in the heat transfer pipe inner wall surface and outer wall surface which concern on Example 5. FIG. It is explanatory drawing of the grooved pipe | tube as an example of the pipe | tube which provided the unevenness | corrugation in the heat exchanger tube inner wall surface which concerns on Example 5. FIG. It is a graph which shows the relationship between a heat exchanger tube inner surface shape and heat transmittance. It is a graph which shows the relationship between the heat transfer tube inner surface shape and pressure loss. It is explanatory drawing of the other example of the heat exchanger tube which provided the unevenness | corrugation in the outer wall surface which concerns on Example 5. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Compressor 3 Condenser 4 Refrigerant piping 5 Thermal storage tank 6 Manufacturing pump 7 Recirculation pump 8 Inlet side flow path 9 Outlet side flow path 12 Recirculation flow path 13 Reservoir tank 14A, 14B Flowmeters 15, 16, 17, 18 Thermometer 19 Refrigerant flow control device 20 Air conditioning load 21 Refrigerant supply device 30 Control device 41 On-off valve

Claims (14)

An aqueous solution of a clathrate hydrate guest compound or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water is allowed to flow inside the heat transfer tube, and a refrigerant around the heat transfer tube A method for producing an clathrate hydrate slurry comprising a step of generating the clathrate hydrate in the aqueous solution or the slurry through heat exchange,
The increase in the amount of clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant is suppressed by the flow force of the aqueous solution or slurry flowing inside the heat transfer tube. A method for producing a clathrate hydrate slurry characterized by the above. An aqueous solution of a clathrate hydrate guest compound or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water is allowed to flow inside the heat transfer tube, and a refrigerant around the heat transfer tube Producing the clathrate hydrate in the aqueous solution or the slurry through heat exchange, comprising the steps of:
A part of the clathrate hydrate adhering to the inner wall surface of the heat transfer tube in the process of heat exchange with the refrigerant is removed by the flow force of the aqueous solution or the slurry, and the remainder is removed from the inner wall surface of the heat transfer tube. A method for producing a clathrate hydrate slurry, wherein the clathrate hydrate slurry is left to cover. The method for producing a clathrate hydrate slurry according to claim 1 or 2, wherein a part or all of the aqueous solution or the slurry that has passed through the heat transfer tube is refluxed to the heat transfer tube. The method for producing a clathrate hydrate slurry according to any one of claims 1 to 3, further comprising a step of adjusting a temperature of the refrigerant. The temperature of the refrigerant is adjusted to a temperature lower than the freezing point of the clathrate hydrate, close to the freezing point, or close to the temperature of the aqueous solution or the slurry flowing inside the heat transfer tube. 4. The method for producing an clathrate hydrate slurry according to 4. A plurality of heat transfer tubes, a refrigerant supply device for supplying a refrigerant to the outer periphery of each heat transfer tube, and an aqueous solution of a clathrate hydrate guest compound or the clathrate hydrate in each heat transfer tube And a flow rate setting device for setting a flow rate of the aqueous solution or the slurry, and heat-exchanged with the refrigerant through the aqueous solution or the slurry. An apparatus for producing an clathrate hydrate slurry in which a clathrate is produced,
The aqueous solution so that an increase in the amount of clathrate hydrate adhering to the inner wall surface of each heat transfer tube is suppressed by the flow rate setting device by the force of the aqueous solution or the slurry flowing inside each heat transfer tube. Alternatively, the clathrate hydrate slurry manufacturing apparatus is characterized in that the flow rate of the slurry is set. A plurality of heat transfer tubes, a refrigerant supply device for supplying a refrigerant to the outer periphery of each heat transfer tube, and an aqueous solution of a clathrate hydrate guest compound or the clathrate hydrate in each heat transfer tube And a flow rate setting device for setting a flow rate of the aqueous solution or the slurry, and heat-exchanged with the refrigerant through the aqueous solution or the slurry. An apparatus for producing an clathrate hydrate slurry in which a clathrate is produced,
A part of the clathrate hydrate adhering to the inner wall surface of each heat transfer tube is removed by the flow rate setting device by the flow force of the aqueous solution or the slurry, and the remaining part remains so as to cover the inner wall surface of each heat transfer tube. The clathrate hydrate slurry manufacturing apparatus is characterized in that the flow rate of the aqueous solution or the slurry is set as described above. The clathrate hydrate slurry manufacturing apparatus according to claim 6 or 7, further comprising turbulence forming means for forming turbulence in the flow of the aqueous solution or slurry supplied to the inside of each heat transfer tube. The package according to any one of claims 6 to 8, wherein unevenness is formed on at least one of an inner wall surface and an outer wall surface of each heat transfer tube along a direction in which the aqueous solution or the slurry flows. A wet hydrate slurry production device. The clathrate hydrate slurry according to any one of claims 6 to 9, further comprising a circulation device for returning a part or all of the aqueous solution or the slurry that has passed through the heat transfer tube to the heat transfer tube. Manufacturing equipment. The clathrate hydrate slurry manufacturing apparatus according to any one of claims 6 to 10, further comprising a refrigerant temperature adjusting device for adjusting a temperature of the refrigerant. A plurality of heat transfer tubes, a refrigerant supply device for supplying a refrigerant to the outer periphery of each heat transfer tube, and an aqueous solution of a clathrate hydrate guest compound or the clathrate hydrate in each heat transfer tube A stock solution supply device for supplying a slurry dispersed or suspended in a solution, a flow rate setting device for setting a flow rate of the aqueous solution or the slurry, and a part or all of the aqueous solution or the slurry that has passed through each heat transfer tube Or a clathrate hydrate slurry production apparatus comprising a circulation device that circulates back to the heat transfer tube as necessary, wherein the clathrate hydrate is produced in the aqueous solution or the slurry through heat exchange with the refrigerant. Driving method,
At the time of the initial operation of the manufacturing apparatus, at the time of restart operation after a pause or at the time of performance check operation, a part of the clathrate hydrate adhering to the inner wall surface of each heat transfer tube is removed by the flow force of the aqueous solution or slurry. The operation method of the clathrate hydrate slurry manufacturing apparatus is characterized in that the remainder is left so as to cover the inner wall surface of each heat transfer tube. A plurality of heat transfer tubes, a refrigerant supply device for supplying a refrigerant to the outer periphery of each heat transfer tube, a refrigerant temperature adjusting device for adjusting the temperature of the refrigerant, and a guest compound of clathrate hydrate in each heat transfer tube A raw solution supply device that supplies an aqueous solution or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water, a flow rate setting device that sets a flow rate of the aqueous solution or the slurry, and each heat transfer tube A circulating device that recirculates a part or all of the aqueous solution or the slurry to the heat transfer tube at all times or as needed, and the clathrate hydrate is contained in the aqueous solution or the slurry through heat exchange with the refrigerant. A method for operating an apparatus for producing a clathrate hydrate slurry to be produced, comprising:
At the time of the initial operation of the manufacturing apparatus, at the time of resuming operation after a stop or at the time of performance confirmation operation, the temperature of the refrigerant is set to a temperature higher than the freezing point of the clathrate hydrate by the refrigerant temperature adjusting device, and each heat transfer tube A part of the clathrate hydrate adhering to the inner wall surface is removed by the flow force of the aqueous solution or slurry, and the remaining part is left so as to cover the inner wall surface of each heat transfer tube The operation method of the manufacturing apparatus of a sum slurry. A plurality of heat transfer tubes, a refrigerant supply device for supplying a refrigerant to the outer periphery of each heat transfer tube, a refrigerant temperature adjusting device for adjusting the temperature of the refrigerant, and a guest compound of clathrate hydrate in each heat transfer tube A raw solution supply device that supplies an aqueous solution or a slurry obtained by dispersing or suspending the clathrate hydrate in the aqueous solution or water, a flow rate setting device that sets a flow rate of the aqueous solution or the slurry, and each heat transfer tube A circulating device that recirculates a part or all of the aqueous solution or the slurry to the heat transfer tube at all times or as needed, and the clathrate hydrate is contained in the aqueous solution or the slurry through heat exchange with the refrigerant. A method for operating an apparatus for producing a clathrate hydrate slurry to be produced, comprising:
During normal operation of the manufacturing apparatus, the refrigerant temperature adjusting device suppresses fluctuations in the temperature of the refrigerant, and a part of the clathrate hydrate adhering to the inner wall surface of each heat transfer tube is removed from the flow of the aqueous solution or slurry. A method for operating an apparatus for producing clathrate hydrate slurry, wherein the clathrate hydrate slurry is removed by force and the remainder is left to cover the inner wall surface of each heat transfer tube.

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