JP4744359B2 - Gas hydrate cooling apparatus and method - Google Patents

Description

The present invention relates to a cooling apparatus and method using gas hydrate as a heat removal source.

Although a heat removal source is required for the cooling device, in recent years, various techniques for utilizing the cold heat of gas hydrate as the heat removal source have been developed. For example, Patent Document 1 discloses a technique of using water generated during dehydration of gas hydrate as a heat removal source in addition to a technique of using gas hydrate itself as a heat removal source.
JP 2003-139357 A

  However, in the technique disclosed in Patent Document 1, the temperature of water generated from the gas hydrate is 0 ° C. or higher (under atmospheric pressure), so this water is used as a heat removal source in a refrigeration system that cools to a temperature of 0 ° C. or lower. There was a problem that it could not be used.

  This invention is made | formed in view of such a subject, and it aims at providing the cooling device and method which can be cooled to below 0 degreeC using the water which isolate | separates from a gas hydrate.

1st invention is the cooling device which uses gas hydrate as a heat removal source,
A tank for storing the gas hydrate;
A vaporization water supply unit that is an aqueous solution in which a freezing point depressant is dissolved in water, and supplies vaporization water for supplying heat to the gas hydrate to decompose it into gas and water;
A recovery unit for recovering from the tank recovered water generated by mixing the cracked water generated by separating the gas hydrate and the water for vaporization in the tank;
A heat exchanger that cools the refrigerant with cold heat of the recovered water;
A vaporizing water regeneration unit for increasing the concentration of the freezing point depressant of the recovered water and regenerating it as the vaporizing water;
It is provided with this.

2nd invention is the cooling device as described in 1st invention, Comprising:
The vaporization water regeneration unit is a cooling device that separates water from the recovered water with an osmosis membrane.

3rd invention is the cooling device as described in 2nd invention, Comprising:
The vaporization water regeneration unit is a cooling device that applies pressure to the recovered water using gas pressure in the tank.

4th invention is the cooling device as described in 3rd invention, Comprising:
A cooling device comprising: a pressure adjusting unit that adjusts a pressure applied to the recovered water of the vaporizing water regeneration unit.

5th invention is the cooling device as described in 1st invention, Comprising:
The vaporization water regeneration unit is a cooling device characterized in that the concentration of the freezing point depressant contained in the recovered water is increased by evaporating the water of the recovered water.

6th invention is the cooling device as described in 1st-5th invention, Comprising:
The vaporization water supply unit supplies only a part of the vaporization water regenerated by the vaporization water regeneration unit to the tank.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling device and method which can be cooled to 0 degrees C or less using the water which isolate | separates from gas hydrate can be provided.

  FIG. 1 is an overall configuration diagram of a cooling device 1 according to an embodiment of the present invention. As shown in the figure, the cooling device 1 of the present embodiment includes a tank 10, a vaporization water supply unit 12, a recovery unit 14, a heat exchanger 20, a vaporization water regeneration unit 30, a vaporization water adjustment valve 46, a pump 47, a gas A pressure control valve 63 and the like are provided.

  The tank 10 is a tank capable of storing a gas hydrate having excellent pressure resistance and heat insulation. The gas hydrate guest gas used in the present invention may be a combustible gas such as natural gas, methane, ethane, propane, butane, or hydrogen. In this case, the generated gas may be used as fuel. it can. Moreover, you may use gas, such as nitrogen, oxygen, and a carbon dioxide, as guest gas.

  The vaporization water supply unit 12 supplies the tank 10 with vaporization water for supplying heat to the gas hydrate and decomposing it into gas and water. As a result, the gas hydrate stored in the tank 10 is decomposed into water and gas, and the decomposition water generated by the decomposition and the vaporization water supplied by the vaporization water supply unit 12 are mixed in the tank 10. Recovered water.

  The water for vaporization used in the present invention is an aqueous solution in which a freezing point depressant such as calcium chloride, sodium chloride or ammonium chloride is dissolved in water, and is a liquid having a freezing point lower than 0 ° C.

  On the other hand, the gas separated and generated from the gas hydrate is sent through the pipe 61 and can be used as appropriate. For example, if the gas hydrate guest gas is a combustible gas, it can be used as a fuel.

  The recovery unit 14 recovers the recovered water generated in the tank 10. The recovered water recovered here is sent to the heat exchanger 20 through the pipe 41.

  The heat exchanger 20 cools the refrigerant by exchanging heat between the recovered water and the refrigerant. The refrigerant cooled here is used for purposes such as freezing, refrigeration, and cooling through the pipe 51. The recovered water that has received heat supply from the refrigerant is sent to the vaporizing water regeneration unit 30 through the pipe 42 by the pump 47.

  The vaporizing water regeneration unit 30 separates the recovered water into vaporizing water and water. That is, in the tank 10, the decomposition water separated from the gas hydrate and the vaporization water are mixed, and the concentration of the freezing point depressant in the recovered water is lower than that in the initial vaporization water. Therefore, the water for recovery is regenerated by removing part of the recovered water and increasing the concentration. In this separation, the concentration may be increased by applying a pressure higher than the osmotic pressure to the recovered water and allowing only the water in the recovered water to permeate through the osmotic membrane. Further, the concentration of the recovered water may be increased by evaporating a part of the recovered water to reduce the water contained in the recovered water.

  When the osmosis membrane is used in the vaporization water regeneration unit 30, the gas in the tank 10 may be supplied through the gas pipes 61 and 62 to apply pressure to the recovered water to promote the separation. In that case, it is good also as adjusting the quantity and density | concentration of the vaporization water produced | generated in the vaporization water reproduction | regeneration part 30 by adjusting the pressure added to recovery water by providing the gas pressure control valve 63 in the gas piping 62. FIG. That is, if the pressure is increased by the gas pressure control valve 63, the pressure applied to the recovered water increases, and the water in the recovered water is promoted to permeate the osmosis membrane, so that high concentration vaporizing water can be regenerated. On the other hand, if the pressure is reduced by the gas pressure control valve 63, the pressure applied to the recovered water decreases, and the water in the recovered water is prevented from passing through the osmosis membrane, so that low concentration vaporization water can be generated. Thus, if the gas pressure control valve 63 is provided, the concentration of the freezing point depressant for the vaporizing water can be adjusted.

  The water generated by separating from the recovered water in the vaporization water regeneration unit 30 can be used as appropriate.

  The vaporization water regenerated by the vaporization water regeneration unit 30 is supplied to the vaporization water supply unit 12 through the pipe 43. At this time, all of the vaporization water generated in the vaporization water regeneration unit 30 may be supplied to the tank 10 through the pipe 45, but a part of the vaporization water regenerated in the vaporization water regeneration unit 30 is divided into the pipe 44. May be supplied to the collection unit 14. The amount of vaporizing water to be diverted to the pipe 44 may be adjusted by the vaporizing water amount adjusting valve 46.

  As described above, according to the cooling device 1 of the present embodiment, it is possible to provide a cooling device and a method capable of cooling to 0 ° C. or lower using the decomposition water generated by the decomposition of the gas hydrate. That is, although water solidifies at 0 ° C. under atmospheric pressure, in this embodiment, by using vaporizing water in which a freezing point depressant such as calcium chloride is dissolved, the freezing point of mixed water is lowered from 0 ° C. A heat removal source having a temperature of ℃ or less can be obtained. Therefore, the refrigerant can be cooled to 0 ° C. or lower by the heat exchanger 20 and can be used for applications that require 0 ° C. or lower, such as refrigeration.

  In this embodiment, if the amount of water for vaporization diverted to the pipe 44 by the vaporization water adjustment valve 46 is increased, the amount of heat supplied to the gas hydrate in the tank 10 is reduced, and the gas hydrate is separated. Since it can suppress and the temperature of recovered water can be raised, the overcooling of the refrigerant | coolant in the heat exchanger 20 can be prevented. On the other hand, if the amount of water for vaporization diverted to the pipe 44 by the vaporization water adjustment valve 46 is increased, the supply of heat to the gas hydrate in the tank 10 is increased, and the separation of the gas hydrate can be promoted. At the same time, since the temperature of the recovered water can be lowered, the refrigerant can be cooled to a lower temperature in the heat exchanger 20.

  In addition, the description of the above embodiment is for facilitating understanding of the present invention, and does not limit the present invention. It goes without saying that the present invention can be changed and improved without departing from the gist thereof, and that the present invention includes equivalents thereof.

It is a whole lineblock diagram of cooling device 1 which is one embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling device 10 Hydrate storage tank 12 Evaporation water supply part 14 Collection | recovery part 20 Heat exchanger 30 Evaporation water reproduction | regeneration part 41,42,43,44,45 Piping 46 Evaporation water amount adjustment valve 47 Pump 51 Refrigerant piping 61,62 Gas piping 63 Gas pressure control valve

Claims (7)

A cooling device using gas hydride as a heat removal source,
A tank for storing the gas hydrate;
A vaporization water supply unit that supplies an aqueous solution in which a freezing point depressant is dissolved in water to supply heat to the gas hydrate and decompose it into gas and water;
A recovery unit for recovering from the tank recovered water generated by mixing the cracked water generated by separating the gas hydrate and the water for vaporization in the tank;
A heat exchanger that cools the refrigerant with cold heat of the recovered water;
A vaporizing water regeneration unit for increasing the concentration of the freezing point depressant of the recovered water and regenerating it as the vaporizing water;
A cooling device comprising: The cooling device according to claim 1,
The vaporizing water regeneration unit separates water from the recovered water with an osmosis membrane. The cooling device according to claim 2,
The cooling apparatus according to claim 1, wherein the vaporization water regeneration unit applies a pressure to the recovered water using a gas pressure in the tank. The cooling device according to claim 3,
A cooling device comprising: a pressure adjusting unit that adjusts a pressure applied to the recovered water of the vaporizing water regeneration unit. The cooling device according to claim 1,
The vaporizing water regeneration unit increases the concentration of a freezing point depressant contained in the recovered water by evaporating the water of the recovered water. The cooling device according to claim 1,
The cooling device, wherein the vaporization water supply unit supplies only a part of the vaporization water regenerated by the vaporization water regeneration unit to the tank. A cooling method using gas hydride as a heat removal source,
Storing the gas hydrate in a tank;
An aqueous solution in which a freezing point depressant is dissolved in water, supplying heat to the gas hydrate to supply vaporizing water for decomposition into gas and water to the tank;
Recovering recovered water generated by mixing the cracked water generated by separating the gas hydrate and the vaporizing water in the tank from the tank;
Cooling the refrigerant with cold heat of the recovered water;
Increasing the concentration of the freezing point depressant of the recovered water and regenerating as the water for vaporization;
The cooling method characterized by including.

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