JP2009249603A - Method and apparatus for forming water film on surface of gas hydrate pellet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To evenly form a water film on the whole surface of a gas hydrate pellet without exceptionally increasing the spray amount of water. <P>SOLUTION: This apparatus for forming the water film on the surface of the gas hydrate pellet sprays water (w) toward the gas hydrate pellet (a) from a water spray device 2 to form the water film on the surface of the gas hydrate pellet while conveying the gas hydrate pellet (a) made by compression forming of the gas hydrate by a pellet belt conveyor 6. Therein, a pellet inversion means 9 of inverting the gas hydrate pellet (a) during the conveyance is disposed on the belt conveyor 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for forming a water film on the surface of a gas hydrate pellet and an apparatus therefor.

  Conventionally, powder gas hydrate is compressed and molded into pellets by a briquette roll type granulator, and the pellets are transported by a belt conveyor provided in a tunnel-type transport device body having a cooling jacket. Further, it is described that water is sprayed from a water spray nozzle toward a pellet being conveyed so that the surface of the pellet is covered with an ice film (for example, see Patent Document 1).

  However, the conventional method is a method in which water is sprayed onto a gas hydrate pellet that is taken out under atmospheric pressure and is below freezing point. Under atmospheric pressure, the natural gas hydrate is kept below the freezing point where it does not decompose. Therefore, when water is sprayed, the pellet surface is decomposed. If the pellet surface is decomposed, the generated gas hydrate will be decomposed, the exhaust gas content will be reduced, the energy required for production will be wasted, and the processing equipment for the decomposed gas will be required. There are problems such as becoming.

  In addition, since the water sprayed from the water spray nozzle freezes before reaching the pellets being transported, it is difficult to cover the surface of the pellets being transported with an ice film. Furthermore, even if the surface of the pellet being transported can be covered with an ice film, it is limited to the upper part of the pellet, that is, the substantially northern hemisphere of the pellet, and the entire surface of the pellet being transported has a uniform thickness of ice. It was difficult to cover with a film.

Therefore, while separating the step of forming a water film on the surface of the pellet being conveyed and the step of freezing the water film formed on the surface of the pellet, it is conceivable to increase the amount of water spray in the previous step. In that case, there is a possibility that new problems such as an increase in the circulation amount of unattached water and an increase in the thickness of the ice film may occur.
JP 2002-220353 A

  The present invention has been made to solve such a problem, and the object of the present invention is to uniformly form a water film on the entire surface of the pellet without particularly increasing the amount of water sprayed. Another object is to provide a method and apparatus for forming a water film on the surface of a gas hydrate pellet.

  A method for forming a water film on the surface of a gas hydrate pellet according to claim 1 of the present application is a method for forming a water film on a surface of a pellet by injecting water onto the pellet formed by compressing the gas hydrate. It is characterized by spraying water under conditions.

  In the method for forming a water film on the surface of a gas hydrate pellet according to claim 2 of the present application, a gas formed by spraying water toward the gas hydrate pellet while the pellet formed by compression molding the gas hydrate is conveyed by a belt conveyor. In the method for forming a water film on the surface of a gas hydrate pellet, which forms a water film on the surface of the hydrate pellet, the gas hydrate pellet being conveyed by a belt conveyor is inverted by a pellet rotating means.

  A method for forming a water film on the surface of a gas hydrate pellet according to claim 3 of the present application is characterized in that in claim 1 or 2, water in which an electrolyte is dissolved is sprayed toward the gas hydrate pellet. is there.

The method for forming a water film on the surface of a gas hydrate pellet according to claim 4 of the present application is characterized in that, in claim 1 or 2, the electrolyte is NaCl, CaCl ₂ , MgCl ₂ , or AgI.

  A water film forming apparatus on the surface of a gas hydrate pellet according to claim 5 of the present application is directed to supplying water from a water spraying device toward the gas hydrate pellet while the pellet formed by compression molding the gas hydrate is conveyed by a belt conveyor. In the water hydrate pellet surface water film forming apparatus for spraying to form a water film on the surface of the gas hydrate pellet, a pellet reversing means for inverting the gas hydrate pellet being conveyed is provided on the belt conveyor. To do.

  The water hydrate pellet surface water film forming apparatus according to claim 6 of the present application uses a roll-like material as pellet inverting means in claim 5, and arranges the roll-like material in the longitudinal direction of the belt conveyor, And the said roll-shaped thing is rotated centering | focusing on the axial center, It is characterized by the above-mentioned.

  The method for forming a water film on the surface of a gas hydrate pellet according to claim 1 of the present application is characterized in that water is sprayed under gas hydrate generation conditions, and water is supplied in a gas hydrate generation region. Since it sprays, there is no problem that the pellet surface decomposes.

  Therefore, the generated gas hydrate does not decompose and the amount of stored gas does not decrease, and the energy required for production is not wasted. Moreover, the processing equipment of the gas decomposed | disassembled by spraying is unnecessary.

  The water spraying step may be performed immediately after granulation, or after granulation or cooling, as long as it is within the gas hydrate production conditions.

  The method for forming a water film on the surface of the gas hydrate pellets according to claim 2 of the present application reverses the gas hydrate pellets being conveyed on the belt conveyor by the pellet rotating means, so that the amount of water sprayed is not significantly increased, Water can be uniformly attached to the entire surface of the gas hydrate pellets.

In the method for forming a water film on the surface of the gas hydrate pellet according to claim 3 of the present application, since the electrolyte is dissolved in the water sprayed toward the pellet, a uniform ice film is formed on the surface of the pellet by the action of the electrolyte. Can be formed. For the electrolyte, NaCl, CaCl ₂ , MgCl ₂ , or AgI is preferably used.

  Since the apparatus for forming a water film on the surface of a gas hydrate pellet according to claim 5 of the present application is provided with pellet inverting means for inverting the gas hydrate pellet being conveyed on the belt conveyor, Water can be uniformly attached to the entire surface of the gas hydrate pellets without particularly increasing the spray amount.

  The apparatus for forming a water film on the surface of a gas hydrate pellet according to claim 6 of the present application uses a roll-like material as pellet reversing means, arranges the roll-like material in the longitudinal direction of a belt conveyor, and the roll shape Since the object is rotated about its axis, the gas hydrate pellets on the belt conveyor can be easily reversed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 3 are flowcharts showing a method for producing gas hydrate pellets. The gas hydrate pellet production process of FIG. 1 includes a gas hydrate production process A, a pellet molding process B, a water spraying process C, and pellet cooling. It comprises a process D, a depressurization process E, and a gas hydrate pellet storage process F.

  However, the present invention is not limited to this process. For example, the order of the water spraying process C and the pellet cooling process D is interchanged, and as shown in FIG. 2, the gas hydrate generating process A, the pellet molding process B, the pellet cooling process D, the water spraying Example of Process C, Depressurization Process E, Gas Hydrate Pellet Storage Process F, or Water Spray Process C and Depressurization Process E are docked to form Gas Hydrate Generation Process A, Pellet Molding as shown in FIG. There are examples of process B, pellet cooling process D, depressurization process E / water spray process C, and gas hydrate pellet storage process F.

  FIG. 4 is an embodiment of the pellet molding step B and the water spraying step C. The water film forming apparatus 2 according to the present invention is installed below the briquette roll type granulating apparatus 1, and water A pellet drum 3 for storing a gas hydrate pellet (hereinafter simply referred to as a pellet) a is installed below the pellet discharge port 5 of the film forming apparatus 2.

  Inside the pressure vessel (not shown) that accommodates these devices, that is, the granulating device 1, the water film forming device 2, and the pellet drum 3, a predetermined pressure (for example, 5.4 MPa) and a predetermined temperature (for example, 5 ° C.).

  The water film forming apparatus 2 includes a belt conveyor 6 in a bowl-shaped water film forming apparatus main body 4 and a water spraying apparatus 7 directly above the belt conveyor 6. This water spraying device 7 comprises a long pipe 8 excluding the pellet drop point, and water spray holes (not shown) are provided at regular intervals on the lower surface thereof. The pipe 8 is disposed in the longitudinal direction of the belt conveyor 6.

  Further, a metal roll 9 for inverting the pellet being conveyed is disposed above the belt conveyor 6. The roll 9 has substantially the same length as the belt conveyor 6 and is disposed in the longitudinal direction of the belt conveyor 6.

  The roll 9 is disposed on the belt conveyor 6 in the vicinity of the belt conveyor 6. Further, the roll 9 is rotated by the electric motor 10 about the axis of the roll 9.

  When the number of rolls 9 is one, it is desirable to use a folding belt conveyor 6 as shown in FIG. When using a belt conveyor having a flat belt surface, it is preferable to use a plurality of rolls in order to prevent pellets from falling. Further, the pellet reversing means is not limited to a metal roll, and for example, a rod-like brush shape in which bristles are planted in the radial direction of the rod-like body may be used.

The water sprayed from the water spray device 2 is water in which an electrolyte such as sodium chloride (NaCl), calcium chloride (CaCl ₂ ), magnesium chloride (MgCl ₂ ), silver iodide (Agl) is dispersed. May be. Since silver iodide has a function of attracting moisture, a uniform ice film can be formed. The amount of silver iodide added is preferably about 1 to 1000 ppm.

  As shown in FIG. 4, the pellet a dropped from the briquette roll type granulator 1 onto the belt conveyor 6 is conveyed by the belt conveyor 6 to the pellet discharge port 5 side of the bowl-shaped water film forming apparatus body 4. In the meantime, since water w is sprayed from the pipe 8 of the water spraying device 2 toward the pellet a, the water w adheres to the surface of the pellet a. Note that the thickness of the water film and the ratio of the amount of spray raw material water to the pellet weight are as shown in FIG.

  On the other hand, since the metal roll 9 provided in the longitudinal direction of the belt conveyor 6 rotates in the direction of the arrow, the pellet a on the belt conveyor 6 is reversed by the metal roll 9, and the water w is uniform on the surface of the pellet a. Adhere to. And the pellet a by which the whole pellet surface was coated with the water w is discharged | emitted from the pellet discharge port 5 of the bowl-shaped water film formation apparatus main body 4 to the pellet drum 3. FIG. The water reaching the bottom of the bowl-shaped water film forming apparatus main body 4 is returned to a predetermined device (for example, a gas hydrate generator or a dehydration tower) through a drain pipe (not shown).

  Since the pellet drum 3 containing the pellet a whose entire surface is coated with water w is transported to a freezer (not shown) and cooled below freezing point (for example, about −20 ° C.), The water w coated on the surface freezes to form a thin ice film i (for example, 10 to 100 μm) on the surface of the pellet a. Thereby, after depressurizing to atmospheric pressure, the ice film suppresses the decomposition of the gas hydrate and can be transported and stored stably.

It is a flowchart which shows the manufacturing method of the 1st gas hydrate pellet. It is a flowchart which shows the manufacturing method of the 2nd gas hydrate pellet. It is a flowchart which shows the manufacturing method of the 3rd gas hydrate pellet. It is a schematic block diagram of the gas hydrate pellet manufacturing apparatus containing the water film forming apparatus which concerns on this invention. It is sectional drawing of the pellet drum which accommodated the pellet coat | covered with the ice film. It is a cross-sectional view of a water film forming apparatus. It is a figure which shows the ratio with respect to the pellet weight of the thickness of a water film, and the amount of spray raw material water.

Explanation of symbols

a Gas hydrate pellet w Water 2 Water spray device 6 Belt conveyor 9 Pellet inversion means

Claims (6)

  A method of spraying water on pellets formed by compressing gas hydrate to form a water film on the pellet surface, wherein water is sprayed under conditions for generating gas hydrate, and water on the surface of gas hydrate pellets Film forming method.   Forming a water film on the surface of the gas hydrate pellet by spraying water toward the gas hydrate pellet and forming a water film on the surface of the gas hydrate pellet while the pellet formed by compression molding of the gas hydrate is conveyed on the belt conveyor A method for forming a water film on a surface of a gas hydrate pellet, characterized in that the gas hydrate pellet being conveyed on a belt conveyor is reversed by a pellet rotating means.   3. The method for forming a water film on the surface of a gas hydrate pellet according to claim 1, wherein water in which the electrolyte is dissolved is sprayed toward the gas hydrate pellet. Electrolyte is NaCl, CaCl _2, MgCl _2, water film forming method according to claim 1 or 2, wherein the gas hydrate pellet surface, characterized in that a AgI.   Gas hydrate pellet surface that forms a water film on the surface of the gas hydrate pellet by spraying water from the water spray device toward the gas hydrate pellet while the pellet formed by compression molding of gas hydrate is conveyed on the belt conveyor In this water film forming apparatus, a pellet inverting means for inverting the gas hydrate pellets being conveyed is provided on the belt conveyor.   A roll-like material is used as the pellet reversing means, the roll-like material is disposed in the longitudinal direction of the belt conveyor, and the roll-like material is rotated about its axis. 5. A water film forming apparatus on the surface of a gas hydrate pellet according to 5.

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