JP2017133826A - Bubble detection device and condensation equipment using bubble detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bubble detection device capable of detecting bubbles existing in a liquid with good sensitivity, and to provide condensation equipment using the bubble detection device.SOLUTION: A bubble detection device 1 is provided in a flow passage in which a liquid which has the possibility of containing bubbles flows, and detects bubbles contained in the liquid. The bubble detection device includes: a vertical container 3 in which a supply pipe 9 for supplying a liquid is connected at a side wall part, and in which a discharge pipe 11 for discharging the liquid is connected at a lower part; a liquid return pipe 5 which is provided at an upper part of the vertical container 3 and which always returns the liquid which has flowed in to a liquid source; and a differential pressure gauge 7 for detecting a differential pressure in a region where bubbles can exist in the vertical container 3 or at one part of the vertical container 3 and the liquid return pipe 5.SELECTED DRAWING: Figure 1

Description

The present invention relates to a bubble detection device for directly condensing evaporative gas discharged from an LNG tank to a low-temperature liquid such as LNG and condensing it, and detecting the presence or absence of bubbles on the downstream side thereof, and a condensation facility using the bubble detection device About.
Note that the gas and the liquid are not particularly limited.

As a condensing facility provided with a condenser that condenses the LNG evaporating gas by direct contact with a low-temperature liquid such as LNG, there is a natural gas reliquefaction system disclosed in Patent Document 1, for example.
The natural gas reliquefaction system of Patent Document 1 includes an evaporative gas compressor that compresses evaporative gas generated from a low-temperature liquid (for example, LNG) stored in a storage tank, and the evaporative gas compressed by the evaporative gas compressor. And a low-temperature liquid sent from the storage tank to mix the evaporated gas in the low-temperature liquid, and a separator provided on the downstream side of the static mixer to separate the gas and liquid that could not be condensed have. Furthermore, a secondary pump that boosts the liquid separated from the separator and taken out from below is connected.

  The separator separates the two using the difference in specific gravity between gas and liquid, takes out the liquid from below the container, and draws out the gas accumulated above the container from above with reference to the position of the liquid level generated in the vessel. I have to.

US6,745,576B1

The technique of Patent Document 1 attempts to remove gas in a separator on the premise that there is gas that cannot be condensed. When the gas flows into the secondary pump connected to the downstream side of the separator, not only the predetermined pump performance can be exhibited but also the pump may be damaged due to cavitation.
In the separator disclosed in Patent Document 1, in order to maintain and stabilize the liquid level in the separator, a horizontal plane cross-sectional area of a certain size is required, and for control based on the liquid level Since a certain amount of length is required in the height direction, the separator inevitably becomes large.
When the separator is enlarged, heat input from the outside increases, and there is a problem that LNG evaporates due to heat input and efficiency is poor.

Therefore, instead of separating the gas that could not be condensed with a separator, the presence or absence of the gas that could not be condensed was detected, and if the gas that could not be condensed was detected, the conditions could be changed so that all the gas could be condensed. It is possible to do so.
For this purpose, it is necessary to provide a bubble detection device that can accurately and instantaneously detect the presence or absence of bubbles on the downstream side of the condenser.

  In this regard, for example, assuming that the separator disclosed in Patent Document 1 is used as a bubble detection device, it has to function as a separator as described above, so it must be enlarged, and the enlarged separator is used as a bubble detection device. When used, in order for the liquid level to change, a large amount of gas must flow in, and the time until the condenser cannot detect a state where the gas cannot be completely condensed becomes longer.

  Further, if a large separator is used as a bubble detection device, LNG is evaporated and gas is generated by heat input from the outside to the separator. For this reason, the combined amount of the gas generated by evaporation and the gas that could not be condensed by the condenser is accumulated in the separator, so it is distinguished whether the accumulated gas is due to evaporation or not fully condensed by the condenser It is not possible to accurately determine whether or not the condenser has condensed.

  The liquid that is required to detect the presence or absence of bubbles with high sensitivity is not limited to the liquid on the downstream side of the condenser that mixes and condenses the LNG evaporation gas with the low-temperature liquid such as LNG as described above. Liquids that may contain bubbles, such as liquids downstream of reaction vessels that cause a chemical reaction by mixing a plurality of liquids, are widely targeted.

  The present invention has been made in order to solve the problems, and is provided in a flow path through which a liquid that may contain bubbles can flow, and a bubble detection device that can detect bubbles contained in the liquid with high sensitivity, and It aims at providing the condensation installation using a bubble detection apparatus.

(1) A bubble detection device according to the present invention is provided in a flow path through which a liquid that may contain bubbles is detected, and detects bubbles contained in the liquid.
A container to which a supply pipe that supplies the liquid and a discharge pipe that discharges the liquid are connected; a liquid return pipe that is provided at an upper part of the container and constantly returns the liquid that has flowed into the liquid source; And a differential pressure gauge for detecting a differential pressure in a region where bubbles may exist in a part of the liquid return pipe.

(2) Further, in the above (1), the container is a vertical container, the supply pipe is connected to a side wall portion of the vertical container, and the discharge pipe is connected to the lower part of the vertical container. It is characterized by being connected.

(3) Further, in the above (1) or (2), a guide means for guiding the liquid supplied from the supply pipe to the upper part of the container is provided.

(4) Moreover, the condensing equipment which concerns on this invention has a condenser which makes gas condense by making a gas contact a liquid directly or indirectly,
The bubble detection device according to any one of the above (1) to (3) installed downstream of the condenser, and based on the temperature of the liquid in the container and the outside air temperature of the bubble detection device It is characterized in that a flow rate adjusting device for adjusting a flow rate of flowing through the liquid return pipe by calculating a liquid return amount in which bubbles are not generated by evaporation in the container is provided.

(5) Further, in the above-mentioned (4), the compressor is provided upstream of the condenser and compresses the gas supplied to the condenser, and the differential pressure gauge signal of the bubble detector is input. And a control device for controlling the output of the compressor based on the signal.

(6) Further, in the above (5), an adjustment valve for adjusting a flow rate is further provided in a flow path between the compressor and the condenser, and the control device is based on a signal from the differential pressure gauge. The output of the compressor and / or the opening of the control valve is controlled.

(7) Further, in the above-described (5) or (6), the apparatus further includes a booster pump that pressurizes the liquid flowing through the discharge pipe, and the control device determines the differential pressure based on a signal from the differential pressure gauge When it is determined that the pressure is smaller than a predetermined value, the compressor and the booster pump are stopped.

The bubble detection device according to the present invention includes a container to which a supply pipe for supplying a liquid and a discharge pipe for discharging the liquid are connected, and a liquid return pipe that is provided at an upper portion of the container and returns the inflowed liquid to the liquid source at all times. And a differential pressure gauge for detecting a differential pressure in the container or in a region where bubbles may exist in the container and a part of the liquid return pipe, thereby maintaining a stable liquid level in the container. Since there is no need to do this, the horizontal cross-sectional area of the container can be reduced, and the bubble detection sensitivity can be increased. Moreover, the heat input from the outside can be made small because a container can be reduced in size.
Furthermore, by always discharging the liquid from the liquid return pipe, there is no liquid accumulation in the container, there is no evaporation in the container, and no bubbles are generated due to external heat input in the container. It is possible to reliably detect the presence of bubbles in the liquid.

It is explanatory drawing of the bubble detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing explaining the guide means provided in a bubble detection apparatus (the 1). It is explanatory drawing explaining the guide means provided in a bubble detection apparatus (the 2). It is explanatory drawing explaining the principle of the differential pressure measurement of the bubble detection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing about the measurement location of the differential pressure | voltage of the bubble detection apparatus which concerns on Embodiment 1 of this invention (the 1). It is explanatory drawing about the measurement location of the differential pressure | voltage of the bubble detection apparatus which concerns on Embodiment 1 of this invention (the 2). It is explanatory drawing of the condensation installation which concerns on Embodiment 2 of this invention. It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 1). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 2). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 3). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 4). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 5). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 6). It is explanatory drawing of the other aspect of the bubble detection apparatus shown in Embodiment 1 (the 7).

[Embodiment 1]
The bubble detection device 1 according to the present embodiment is provided on the downstream side of the condenser that liquefies the evaporated gas by directly or indirectly contacting the LNG evaporated gas with a low temperature liquid such as LNG, for example, and condenses in the condenser. FIG. 1 shows a bubble detection device 1 for detecting a bubble that has not been formed. As shown in FIG. 1, a vertical container 3, a liquid return pipe 5 connected to a liquid return port 4 at the top of the vertical container 3, A differential pressure gauge 7 for detecting the differential pressure in the mold container 3 is provided.
Hereinafter, each of the constituent elements will be described in detail by taking as an example the case where the bubble detection device 1 is installed on the downstream side of the condenser that liquefies the evaporated gas by directly contacting the evaporated gas of LNG with a low temperature liquid such as LNG. .

<Vertical container>
The vertical container 3 is, for example, a cylindrical container, and its minimum diameter is not limited, but it can be made as small as the discharge pipe. The cross-sectional shape of the vertical container 3 can take any shape such as a rectangle in addition to a circle. The vertical container 3 does not have the purpose of separating gas and liquid unlike the separator of Patent Document 1, so that a large capacity is not required.

A supply pipe connecting portion 8 is provided on the side wall of the vertical container 3, and a supply pipe 9 for supplying a mixed liquid in which gas and liquid are mixed by a condenser is connected to the supply pipe connecting portion 8.
In addition, a discharge port 10 is provided in the lower part of the vertical container 3, and a discharge pipe 11 that discharges the liquid mixture supplied to the vertical container 3 toward downstream equipment is connected to the discharge port 10. .
1, 2, and 4 to 6, the boundary between the liquid return port 4 and the liquid return pipe 5 of the vertical container 3, and the boundary between the supply pipe connection 8 and the supply pipe 9 of the vertical container 3. , And the boundary between the discharge port 10 and the discharge pipe 11 of the vertical container 3 are indicated by broken lines. However, in the actual machine, the broken line portion is a connection portion by flange, welding, or the like.

Most of the mixed liquid supplied to the vertical container 3 is discharged from the discharge pipe 11, and a small amount of the mixed liquid is discharged from the liquid return pipe 5 provided on the upper part of the vertical container 3.
Thus, since the liquid mixture is always returned from the liquid return pipe 5 to the liquid source, the liquid mixture does not easily stay in the vertical container 3, and bubbles are not easily generated by evaporation due to heat input.

However, depending on the shape or the like of the vertical container 3, a flow that causes a shortcut to the discharge pipe 11 occurs in the vertical container 3, and the mixed liquid stays in a space above the supply pipe connection portion 8 of the vertical container 3. Is also possible. When the stagnation occurs, bubbles are generated due to heat input in the region, so that the bubbles cannot be distinguished from the bubbles generated without being condensed by the condenser.
Therefore, in order not to cause the above-described shortcut, a guide means 13 for guiding the flow of the mixed solution supplied from the supply pipe 9 to the opposite vertical direction of the discharge pipe 11, that is, the upper part of the vertical container 3 may be provided. preferable.

As an example of the guide means 13, as shown in FIG. 2 (a), the tip of the supply pipe connecting portion 8 is extended into the vertical container 3, and the tip is bent upward. As shown in FIG. 2B, the tip of the supply pipe connecting portion 8 is bent obliquely upward, or the liquid that has flowed into the tip of the supply pipe connecting portion 8 as shown in FIG. It is possible to provide a rectifying plate 15 against which the liquid flows and guide the liquid that flows in toward the upper part of the vertical container 3.
In addition, as a specific shape of the baffle plate 15 shown in FIG.2 (c), as shown to Fig.3 (a), a rectangular thing with a front wall, a side wall, and a bottom wall, or FIG.3 (b) As shown in (), one having a bottom wall and a curved wall is conceivable.

<Liquid return pipe>
The liquid return pipe 5 is connected to the liquid return port 4 at the upper part of the vertical container 3 to constantly return the mixed liquid flowing into the liquid source, for example, a storage tank.
Most of the mixed liquid supplied to the vertical container 3 is discharged from the lower discharge pipe 11 and a part thereof is always returned to the liquid source by the liquid return pipe 5. Therefore, there is no liquid level in the vertical container 3, and the liquid is always full. This point is different from that in which the liquid level exists in the container like the separator disclosed in Patent Document 1.

The liquid return pipe 5 is provided with a flow rate adjusting valve 17 for adjusting the flow rate and a temperature detector 18 for measuring the temperature of the liquid flowing in the pipe. The flow rate adjusting valve 17 is based on the outside air temperature and the temperature of the mixed liquid. The opening degree is adjusted by the flow rate adjusting valve control unit 19.
The amount of liquid that is always discharged from the liquid return pipe 5 needs to be a sufficient amount so that bubbles are not generated due to heat input in the vertical container 3. This sufficient amount will be described later.

<Differential pressure gauge>
The differential pressure gauge 7 detects a differential pressure in the vertical container 3 or in a region where bubbles are present in the vertical container 3 and part of the liquid return pipe 5. Since the bubbles exist above the inflow portion of the mixed liquid in the vertical container 3, the upper and lower positions for detecting the differential pressure may be at least on the upper side above the inflow portion of the mixed liquid. However, in order to detect the differential pressure with high sensitivity, it is better that the amount of liquid relative to the amount of bubbles is smaller, so it is better to make the horizontal cross-sectional area as small as possible at the upper position. Further, since it cannot be detected unless bubbles are above the lower position, the lower position is preferably the same as or slightly lower than the inflow portion of the mixed liquid.
By detecting the differential pressure, it is possible to detect the presence or absence of bubbles in the vertical container 3, which will be described below with reference to FIG.

Assuming that the inside of the vertical container 3 is full, it is assumed that the liquid of density ρ is clogged. As shown in FIG. 4, when the distance (height) between point A (pressure P1), which is the lower differential pressure detection position, and point B (pressure P2), which is the upper differential pressure detection position, is H. , The differential pressure ΔP at point A and point B is
ΔP = P1-P2 = ρ ・ g ・ H
It becomes.
Here, if bubbles enter the vertical container 3, even if the liquid level is not formed, if the bubbles are between point A and point B, that is, in the range of height H, ΔP is ρ · g · H. Since it is lower than that, bubbles can be seen.

In order to increase the detection sensitivity of the bubbles, the ratio of the amount of bubbles existing within a predetermined height range to the liquid amount may be increased. For that purpose, it is better to make the horizontal cross-sectional area in the range in which the differential pressure is measured as small as possible. For example, as shown in FIG. 5, the supply pipe 9 is connected as high as possible to the vertical container 3 and disposed on the liquid return pipe 5 that is the upper differential pressure detection position, as shown in FIG. 6. It is preferable that the range in which the differential pressure is taken is all within the vertical container 3.
The volume below the supply pipe 9 in the vertical container 3 functions as a buffer capacity to prevent the gas from flowing downstream through the discharge pipe 11 when a large amount of gas is mixed. Therefore, it is better to connect the supply pipe 9 to the upper part of the vertical container 3 as much as possible from the viewpoint of securing such a buffer capacity.

In the bubble detection device 1 of the present embodiment configured as described above, a mixed liquid that is condensed by a condenser and mixed with gas and liquid is supplied from the supply pipe 9 to the vertical container 3, most of which is A small amount of the mixed liquid is discharged from the discharge pipe 11 and returned to the liquid source from the liquid return pipe 5. Therefore, as described above, the inside of the vertical container 3 is always full.
Further, the flow rate adjusting valve 17 provided in the liquid return pipe 5 is adjusted to a sufficient flow rate so as not to generate bubbles due to heat input in the vertical container 3 as described above.
In this respect, in the present embodiment, the amount of heat input from the outside is calculated based on the outside air temperature and the temperature of the internal fluid, and the opening degree of the flow rate adjusting valve 17 is adjusted based on the calculated amount of heat input to the liquid return pipe 5. Ensure that the flow rate exceeds the flow rate.
Hereinafter, the liquid flow rate that flows through the liquid return pipe 5 in order to prevent generation of bubbles will be described.

Heat input from outside: q, specific heat of liquid: Cp, liquid mass flow rate: m, surface area from connection position of supply pipe 9 to differential pressure measurement position (upper side) (vertical container 3 + liquid return pipe 5): A, liquid Temperature: Ti, boiling point of liquid Tb, external air temperature: To, heat transfer rate: α,
q = A x α x (To-Ti)
Since it is necessary for the liquid to have a boiling point or less in order not to generate bubbles,
(Tb-Ti) × Cp × m> q
If so, no bubbles are generated. Accordingly, the liquid return pipe 5 may have a liquid discharge amount equal to or higher than the flow rate m represented by the following expression.
m> q / ((Tb−Ti) × Cp)

  When there is almost no change in the liquid temperature, an amount of liquid sufficiently larger than the assumed heat input amount may be discharged from the liquid return pipe 5 without providing a thermometer or a liquid thermometer. In this case, it is desirable to flow at least twice the calculated required flow rate.

  When bubbles are mixed in the mixed liquid supplied from the supply pipe 9, the bubbles rise in the vertical container 3 as shown in FIGS. At this time, a change occurs in the differential pressure, that is, the differential pressure decreases, and the presence of bubbles is detected.

In the bubble detection device 1 according to the present embodiment, since it is not necessary to maintain the liquid level stably in the vertical container 3, the horizontal cross-sectional area of the vertical container 3 can be reduced, and the bubble detection sensitivity can be increased. Moreover, since the vertical container 3 can be reduced in size, heat input from the outside can be reduced.
Further, by always discharging the liquid from the liquid return pipe 5, it is difficult for the liquid to stay in the vertical container 3, and bubbles are not generated due to external heat input in the vertical container 3. The presence of bubbles in the supplied mixed liquid can be reliably detected.

In addition, by providing the guide means 13 shown in FIGS. 2 and 3, it is possible to more reliably eliminate a liquid retention region in the vertical container 3, and bubbles are generated by heat input in the vertical container 3. Can be reliably prevented.
Furthermore, by providing the flow rate adjusting valve 17 in the liquid return pipe 5, it is possible to control the liquid discharge amount from the liquid return pipe 5 with respect to changes in the air temperature and the liquid temperature, and more reliably generate bubbles. Can be prevented.

[Embodiment 2]
The present embodiment relates to a condensation facility 21 provided with the bubble detection device 1 of the first embodiment.
FIG. 7 shows an example in which the bubble detection device 1 is provided on the downstream side of a condenser 25 that mixes and condenses the LNG evaporating gas into the LNG delivered from the storage tank 23 that stores LNG.
As shown in FIG. 7, the condensing facility 21 of the present embodiment compresses the evaporative gas extracted from the evaporative gas extraction tube 27 and the evaporative gas extraction tube 27 for extracting the evaporative gas generated from the LNG in the storage tank 23. The evaporative gas compressor 29, the gas supply pipe 31 for supplying the evaporative gas compressed by the evaporative gas compressor 29 to the condenser 25, the control valve 33 provided in the gas supply pipe 31, and the gas supply pipe 31 A condenser 25 that condenses the gas, a delivery pipe 35 that is provided in the storage tank 23 and delivers LNG, and a discharge pump 37 that is provided in the delivery pipe 35 and delivers the LNG toward the condenser 25 are provided.

A supply pipe 9 is provided on the downstream side of the condenser 25, and the vertical container 3 of the bubble detection device 1 of the first embodiment is connected to the supply pipe 9. A discharge pipe 11 is connected to the lower part of the vertical container 3, and a pressure pump 39 for further boosting the mixed liquid is provided in the discharge pipe 11.
Note that the vertical container 3 of the bubble detection device 1 is disposed at a position higher than the condenser 25 and faces the vertical container 3 from the condenser 25 to the vertical container 3 so that no gas accumulates in the pipe. It is preferable to create an upward gradient. Alternatively, if there is a portion that is convex upward in the path from the condenser 25 to the vertical container 3, gas will accumulate, so it is preferable not to provide such a portion.

  Further, a control device 41 for controlling the output and start / stop of the evaporative gas compressor 29, the discharge pump 37, the booster pump 39, and the opening degree of the control valve 33 is provided. Each device is controlled based on the pressure signal.

Next, an operation method of the condensing equipment 21 of the present embodiment configured as described above will be described.
LNG is sent out from the storage tank 23 by the discharge pump 37 and supplied to the condenser 25 through the delivery pipe 35.
On the other hand, the evaporative gas of LNG is extracted from the storage tank 23 via an evaporative gas extraction pipe 27, and this evaporative gas is compressed by the evaporative gas compressor 29, and is installed on the downstream side of the evaporative gas compressor 29. The gas supply amount is adjusted by the valve 33 and supplied to the condenser 25 through the gas supply pipe 31.

  In addition, a predetermined flow rate of LNG that does not generate bubbles due to heat input in the vertical container 3 is constantly discharged from the liquid return pipe 5 and returned to the storage tank 23.

The re-liquefied mixed liquid is supplied to the vertical container 3 of the bubble detection device 1, most of which is discharged from the discharge pipe 11 and sent to the booster pump 39. A part of the mixed liquid supplied to the vertical container 3 is returned to the storage tank 23 via the liquid return pipe 5.
In the bubble detection device 1, the differential pressure is always detected, and the information is input to the control device 41. When a bubble is detected by the bubble detection device 1, the control device 41 outputs, starts / stops, and adjusts the output of the evaporative gas compressor 29, the discharge pump 37, and the booster pump 39 when the detected amount exceeds a predetermined value. The opening degree of the valve 33 is controlled.
An example of control by the control device 41 is as follows.

When the differential pressure becomes smaller than a certain threshold (for example, the differential pressure is reduced by 10% of the reference value), the gas supply to the condenser 25 is decreased. As this method, there is a method of reducing the output of the evaporative gas compressor 29 or reducing the opening of the control valve 33.
When the differential pressure is further reduced (for example, the differential pressure is reduced by 20% of the reference value), it is assumed that a large amount of gas has flowed into the bubble detection device 1, and an evaporative gas compressor 29 that supplies the gas to the condenser 25, And the booster pump 39 is stopped.
Further, the output of the discharge pump 37 is controlled by the control device 41 in accordance with a decrease in the output of the evaporative gas compressor 29, a stop of the evaporative gas compressor 29, and a stop of the booster pump 39.

Note that the capacity of the lower part from the supply pipe connection 8 of the vertical container 3 is Q (m ³ ), the operating flow rate of the booster pump 39 is V (m ³ / s), and the booster pump 39 is stopped by receiving a stop signal. T (s), the gas flows to the booster pump 39 by setting the capacity of the lower part from the supply pipe connecting portion 8 of the vertical container 3 of the bubble detecting device 1 to V × t or more. Can be prevented.

  As described above, according to the condensing facility 21 of the present embodiment, the highly sensitive and high reaction speed bubble detection device 1 is provided so that the condensation in the condenser 25 can be reliably performed when bubbles are detected. When the amount of evaporative gas supplied to the condenser 25 is adjusted, or when a large amount of bubbles flows downstream of the condenser 25, the device is stopped, so that the bubbles are sent to the booster pump 39. It can be surely prevented.

  In the above example, the control valve 33 is provided on the downstream side of the evaporative gas compressor 29. Therefore, as a coping method when bubbles are detected by the bubble detection device 1, the evaporative gas compressor 29 and / or Alternatively, the control valve 33 is provided, but it is not essential to provide the control valve 33. If the control valve 33 is not provided, the output of the evaporative gas compressor 29 may be controlled.

  In the above embodiment, the case where the bubble detection device 1 is installed on the downstream side of the condenser 25 that directly contacts the LNG evaporation gas to liquefy the evaporation gas has been described as an example. The bubble detection device is not limited to the above case. For example, a flow in which a liquid that may contain bubbles, such as a liquid downstream of a reaction vessel that causes a chemical reaction by heating or mixing a plurality of liquids, flows. It can be used on the road.

In the first embodiment, the guide means 13 shown in FIG. 2 is shown as an example. However, the guide means 13 is not limited to this. For example, as shown in FIG. You may comprise with the partition plate connected to the lower part (bottom part) of the type | mold container 3, extended upwards, and the upper end part being the open end in the vertical type | mold container 3. FIG.
The position of the open end of the guide means (partition plate) 13 is preferably a position as far as possible from the supply pipe connection portion 8 and the discharge port 10 in order to prevent a flow that is short-circuited to the discharge pipe 11. The height of the point A, which is the lower differential pressure detection position, is preferably the same height as the open end of the guide means 13.

Further, in the first embodiment and FIG. 8, regarding the connection position of the supply pipe 9 and the discharge pipe 11 to the vertical container 3, the supply pipe 9 is connected to the side wall portion of the vertical container 3 and the discharge pipe 11 is vertical. Although the example connected to the lower part (bottom part) of the type | mold container 3 was shown, this invention is not restricted to this, Various modes as shown in FIGS. 9-12 can be taken.
Hereinafter, these other aspects will be described.

The example shown in FIG. 9 is an example in which the supply pipe 9 is connected to the lower part (bottom part) of the vertical container 3 and the discharge pipe 11 is connected to the side wall part of the vertical container 3.
As a mode of the guide means 13 in this case, as shown in FIG. 9A, the tip of the supply pipe connecting portion 8 is extended to a position above the discharge port 10, or a configuration shown in FIG. ) Is a partition plate whose lower end is connected to the lower part (bottom) of the vertical container 3, extends upward, and has an open end whose upper end is opened at a position above the discharge port 10. It may be configured.
At this time, the height of the point A, which is the lower differential pressure detection position, is preferably the same height as the upper end of the guide means 13.

The example shown in FIG. 10 is an example in which the supply pipe 9 is connected to the lower part (bottom part) of the vertical container 3 and the discharge pipe 11 is also connected to the lower part (bottom part) of the vertical container 3.
As an aspect of the guide means 13 in this case, as shown in FIG. 10 (a), the tip of the supply pipe connecting portion 8 is extended upward, or as shown in FIG. 10 (b), the lower end A part may be comprised with the partition plate used as the open end which is connected to the lower part (bottom part) of the vertical container 3, and an upper end part is extended upwards and opened.
At this time, the height of the point A, which is the lower differential pressure detection position, is preferably the same height as the upper end of the guide means 13 as in the example shown in FIG.

The example shown in FIGS. 11 and 12 is an example in which the supply pipe 9 and the discharge pipe 11 are both connected to the side wall portion of the vertical container 3.
In this case, the arrangement in the circumferential direction of the vertical container 3 in the supply pipe 9 and the distribution pipe 11 is not particularly limited. For example, as shown in FIGS. Alternatively, as shown in FIG. 12, it may be the same side surface, or although not shown, the supply pipe 9 and the distribution pipe 11 may be displaced at a predetermined angle in the circumferential direction.
Further, the vertical arrangement of the vertical container 3 in the supply pipe 9 and the discharge pipe 11 may be provided with a step as shown in FIGS. 11 (a) and 12 (b). As shown in FIG.

However, it is necessary to consider the arrangement of the supply pipe 9 and the discharge pipe 11 and the way of providing the guide means 13 so that bubbles are not discharged from the discharge pipe 11.
As shown in FIG. 11A, when the position of the supply pipe 9 is higher than the discharge pipe 11 and the positions of the supply pipe 9 and the discharge pipe 11 are separated in the circumferential direction of the vertical container 3. In some cases, the guide means 13 may not be provided.
On the other hand, when the height positions of the supply pipe 9 and the discharge pipe 11 are the same, the lower end portion is connected to the lower portion (bottom portion) of the vertical container 3 and extends upward as shown in FIG. It is preferable to provide a guide means 13 composed of a partition plate that is opened and has an open end whose upper end is opened at a position above the discharge port 10.

  However, even if the position of the supply pipe 9 is higher than that of the discharge pipe 11, as shown in FIG. Is connected to the side wall of the vertical container 3 and a partition plate is provided between the supply pipe 9 and the discharge pipe 11 so that the other end extends into the vertical container 3 and is an open end that opens inside the container. It is preferable to do this.

In the first embodiment, the vertical container 3 is exemplified as an example of the container of the present invention. However, the shape of the container is not limited to the vertical type, and various shapes can be applied.
For example, as shown in FIGS. 13 and 14, even in the case of a container 43 having a U-shaped upside down so as to protrude upward in the installed state (hereinafter referred to as “reverse U-shaped container 43”). Good.

The arrangement of the supply pipe 9 and the discharge pipe 11 in the case of the inverted U-shaped container 43 can take various forms. As shown in FIG. The supply pipe 9 is connected to the side wall and the discharge pipe 11 is connected to the bottom of the other side, or the supply is supplied to the bottom of one side of the inverted U-shaped container 43 as shown in FIG. Connect the pipe 9 and connect the discharge pipe 11 to the side wall of the other side, or connect the supply pipe 9 to the bottom of one side of the inverted U-shaped container 43 as shown in FIG. Connect, connect the discharge pipe 11 to the bottom of the other side, or connect the supply pipe 9 to the side wall of one side of the inverted U-shaped container 43, as shown in FIG. The discharge pipe 11 can be connected to the side wall of the other side.
In addition, the cross-sectional shape of the inverted U-shaped container 43 can take any shape such as a rectangle in addition to a circle. When the inverted U-shaped container 43 is, for example, a cylindrical container, the minimum diameter is not limited, but it can be made as small as the discharge pipe 11 or the supply pipe 9 or both.

  In the case of the inverted U-shaped container 43, the inner wall of the side portion to which the supply pipe 9 is connected functions as the guide means 13, so that the supplied mixed liquid can be supplied to the discharge pipe 11 without providing the separate guide means 13. The flow of shortcuts can be prevented.

When the bubble detection device 1 is applied to the condensing facility 21 of the second embodiment, the bubble detection device 1 is supplied as shown in FIGS. 9, 10, 13 (b), and 14 (a). When the pipe 9 is connected to the lower part of the container (vertical container 3, inverted U-shaped container 43), a condenser in which the mixed fluid is discharged vertically upward is used. It is preferable to connect the bubble detection device 1 to the upper side.
With such an arrangement, it is possible to shorten the time from the generation of bubbles in the condenser to the detection. In addition, since the bubble detection device 1 is disposed at a relatively high position, the liquid head in the bubble detection device 1 is small and bubbles are likely to be generated. It can be detected.

DESCRIPTION OF SYMBOLS 1 Bubble detection apparatus 3 Vertical container 4 Liquid return port 5 Liquid return tube 7 Differential pressure gauge 8 Supply pipe connection part 9 Supply pipe 10 Discharge port 11 Discharge pipe 13 Guide means 15 Current control plate 17 Flow rate adjustment valve 18 Temperature detector 19 Flow rate adjustment Valve control unit 21 Condensing equipment 23 Reservoir 25 Condenser 27 Evaporating gas outlet pipe 29 Evaporating gas compressor 31 Gas supply pipe 33 Control valve 35 Delivery pipe 37 Discharge pump 39 Boosting pump 41 Control device 43 Inverted U-shaped container

Claims (7)

A bubble detection device that detects bubbles included in the liquid provided in a flow path through which a liquid that may contain bubbles may flow,
A container to which a supply pipe that supplies the liquid and a discharge pipe that discharges the liquid are connected; a liquid return pipe that is provided at an upper part of the container and constantly returns the liquid that has flowed into the liquid source; A bubble detecting device comprising: a differential pressure gauge for detecting a differential pressure in a container and a region where bubbles may exist in a part of the liquid return pipe.   2. The bubble according to claim 1, wherein the container comprises a vertical container, the supply pipe is connected to a side wall portion of the vertical container, and the discharge pipe is connected to a lower part of the vertical container. Detection device.   The bubble detection device according to claim 1, further comprising guide means for guiding the liquid supplied from the supply pipe to an upper portion of the container. A condensing facility having a condenser for condensing the gas by bringing the gas into direct or indirect contact with the liquid,
It has a bubble detection device according to any one of claims 1 to 3 installed downstream of the condenser,
A flow rate adjusting device that calculates a liquid return amount in which bubbles are not generated by evaporation in the container based on the temperature of the liquid in the container and the outside air temperature of the bubble detection device, and adjusts the flow rate through the liquid return pipe Condensing equipment characterized by having   A control provided on the upstream side of the condenser for compressing the gas supplied to the condenser and a differential pressure gauge signal of the bubble detection device, and controlling the output of the compressor based on the signal The condensation equipment according to claim 4, further comprising an apparatus.   A control valve for adjusting a flow rate is further provided in a flow path between the compressor and the condenser, and the control device outputs the output of the compressor and / or the opening of the control valve based on a signal from the differential pressure gauge. The condensing equipment according to claim 5, wherein the condensing equipment is controlled.   A booster pump for boosting the liquid flowing through the discharge pipe, and when the controller determines that the differential pressure has become smaller than a predetermined value based on a signal from the differential pressure gauge, the compressor and the booster pump are The condensing equipment according to claim 5 or 6, wherein the condensing equipment is stopped.

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