JP6600565B2 - Clathrate manufacturing method - Google Patents

Description

  The present invention relates to a clathrate production method for producing a clathrate containing a gas as a guest substance.

  Among the clathrates, clathrate hydrate is a crystal in which molecules other than water molecules are included in a clathrate structure (a cage structure) formed by hydrogen bonding between water molecules. Water molecules that form a cage structure in clathrate hydrate are called host molecules, and molecules that are included (encapsulated) are called guest substances (guest molecules). Among such clathrate hydrates, those enclosing gas as a guest substance are called gas hydrates, and for example, methane hydrate, carbon dioxide hydrate, ozone hydrate and the like are known. Gas hydrate is attracting attention as a substance having a high gas occluding property because it can occupy a guest substance 120 times or more of its own volume.

  As a technique for producing such gas hydrate, a raw material gas containing a guest substance is compressed to a predetermined pressure, and water is compressed to a predetermined pressure and mixed to dissolve the guest substance in the raw material gas in water. A technique for generating gas hydrate by cooling water in which a guest substance is dissolved to a predetermined temperature has been developed (for example, Patent Document 1).

JP 2002-356665 A

  However, in the technique disclosed in Patent Document 1, when the source gas is compressed, the temperature of the source gas may rise and decompose.

  Then, in view of such a subject, this invention aims at providing the clathrate manufacturing method which can compress raw material gas, suppressing decomposition | disassembly of raw material gas.

  In order to solve the above problems, a clathrate production method of the present invention is a clathrate production method for producing a clathrate containing a first gas as a guest substance, wherein the first clathrate is produced at a first pressure and a first temperature. A step of containing the gas in the storage tank, and a second gas having a second pressure higher than the first pressure and a second temperature lower than the first temperature is introduced into the storage tank to exceed the first pressure and less than the second pressure. And a step of mixing the first gas and the second gas to generate a mixed gas so as to achieve the third pressure.

  In addition, the step of generating the mixed gas has a third pressure higher than a predetermined third temperature exceeding the upper limit of the generation temperature of the clathrate enclosing the second gas, and suppressing the temperature rise of the first gas. The first gas and the second gas may be mixed so that

  Further, it may include a step of further boosting the pressure of the mixed gas generated in the step of generating the mixed gas.

  Further, the first gas may be ozone.

  The second gas may be carbon dioxide.

  According to the present invention, the source gas can be compressed while suppressing the decomposition of the source gas.

It is a figure for demonstrating the schematic structure of a clathrate manufacturing apparatus. It is a figure explaining the specific structure of a gas pressurization unit. It is a flowchart explaining the flow of a process of a clathrate manufacturing method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Clath rate manufacturing apparatus 100)
FIG. 1 is a diagram for explaining a schematic configuration of a clathrate manufacturing apparatus 100. As shown in FIG. 1, the clathrate manufacturing apparatus 100 includes a gas boosting unit 110 and a clathrate manufacturing unit 120. Here, an explanation will be given by taking ozone hydrate as an example of the clathrate.

  The gas pressurization unit 110 boosts the raw material gas containing ozone (first gas) and carbon dioxide (second gas) to a pressure at which the clathrate production unit 120 can efficiently produce ozone hydrate.

  The clathrate production unit 120 mixes the raw material gas boosted by the gas pressure boosting unit 110 and water under a predetermined pressure and a predetermined temperature environment to manufacture ozone hydrate (clathrate). As described above, the source gas contains carbon dioxide in addition to ozone. Since carbon dioxide functions as an accelerator in the ozone hydrate production reaction, the production of ozone hydrate can be promoted by mixing carbon dioxide with the raw material gas. In addition, since manufacture of ozone hydrate itself can utilize various existing techniques, detailed description is omitted here.

  Thus, in order to produce ozone hydrate, it is necessary to increase the pressure of ozone (first gas) to a predetermined pressure. However, when compressed by a compressor as in the prior art, the temperature of the gas increases, Has the problem of breaking down. Therefore, the gas booster unit 110 of the present embodiment suppresses ozone decomposition by compressing ozone without using a compressor. Hereinafter, a specific configuration of the gas booster unit 110 will be described in detail.

(Gas boosting unit 110)
FIG. 2 is a diagram illustrating a specific configuration of the gas booster unit 110 according to the present embodiment. In FIG. 2, the flow of liquid and gas is indicated by solid arrows. As shown in FIG. 2, ozone and carbon dioxide are introduced into the first cylinder 210 (accommodating tank) of the gas booster unit 110, and a mixed gas of ozone and carbon dioxide is generated in the first cylinder 210. The mixed gas generated in this way is supplied to the clathrate production unit 120 via the pipe 220.

  A second cylinder 410 is connected to the end of the first cylinder 210 opposite to the connection portion of the pipe 220 via a pipe 222, and water is introduced from the second cylinder 410 or from the first cylinder 210. Water is discharged.

  In addition, a water supply / drainage means 310 is provided between the connection location of the first cylinder 210 and the connection location of the second cylinder 410 in the pipe 222, and the water supply / drainage means 310 supplies water to the pipe 222, Water is discharged from the pipe 222.

  Furthermore, the 1st cooling pipe 212 is provided in the outer periphery of the 1st cylinder 210, and the refrigerant | coolant (for example, alcohol aqueous solution, condensable refrigerant | coolant) cooled by the refrigerator 230 through the piping 224 is provided in the 1st cooling pipe 212. (R-404A) and the like are supplied. Thereby, the inside of the 1st cylinder 210 can be maintained at predetermined 1st temperature (for example, about 2 ° C). In addition, the refrigerant heated by cooling the inside of the first cylinder 210 (heat exchanged refrigerant) is sent from the first cooling pipe 212 to the refrigerator 230 through the pipe 226 and is cooled again in the refrigerator 230. It becomes.

  Oxygen stored in the oxygen supply facility 240 (for example, an oxygen cylinder) is introduced into the ozone generator 242, and ozone is generated from the oxygen in the ozone generator 242. The pressure (first pressure) of ozone (ozone-containing gas) generated in the ozone generator 242 is, for example, 0.4 MPa, and the temperature is, for example, room temperature (about 20 ° C.).

  The ozone generator 242 is connected to the pipe 220 via the pipe 244, and the ozone generated by the ozone generator 242 is introduced into the first cylinder 210 via the pipe 244 and the pipe 220. Further, surplus ozone generated in the ozone generator 242 is introduced into a deozonizer 430, which will be described later, via a pipe 246 and a valve 246a, and decomposed.

  Carbon dioxide (second gas) stored in a carbon dioxide supply facility 250 (for example, a carbon dioxide cylinder) is introduced into the first cylinder 210 via the pipes 252 and 220. The pipe 252 is provided with a pressure adjustment valve 254, a heater 256, an expansion valve 258, and a valve 252a in this order from the upstream side. The pressure adjustment valve 254 adjusts the carbon dioxide stored in the carbon dioxide supply facility 250 to a predetermined second pressure (for example, 4.7 MPa). The heater 256 heats the second pressure carbon dioxide to about 10 ° C.

  The expansion valve 258 expands carbon dioxide and introduces it into the first cylinder 210. Here, the expansion valve 258 is configured so that the pressure in the first cylinder 210 (that is, the pressure of the mixed gas of ozone and carbon dioxide) becomes a predetermined third pressure (for example, about 1.628 MPa). Carbon dioxide is expanded so that the temperature in the first cylinder 210 is equal to or higher than a predetermined third temperature (the temperature of the expanded carbon dioxide is, for example, −60 ° C. to −32 ° C.). Here, the third temperature is a temperature that exceeds the upper limit (about −2.2 ° C.) of the generation temperature of carbon dioxide hydrate. For example, when the third temperature is set to 2 ° C., the carbon dioxide expanded by the expansion valve 258 has an average of about −46 ° C.

  The valve 252a is introduced into the first cylinder 210 while adjusting the introduction amount of carbon dioxide so that the inside of the first cylinder 210 does not fall below the third temperature, that is, the temperature inside the first cylinder 210 gradually decreases. .

  A pipe 222 is connected to the second cylinder 410, and water is introduced from the first cylinder 210 and the water supply / drainage means 310. Further, a deozonizer 430 is connected to the end of the second cylinder 410 opposite to the connection portion of the pipe 222 via the pipe 420, and the gas in the second cylinder 410 is sent to the deozonizer 430 to generate ozone. After being decomposed, it will be released into the atmosphere.

  The oxygen supply equipment 240 is connected to the pipe 420 via the pipe 422, and oxygen (pressed gas) is introduced from the oxygen supply equipment 240 into the second cylinder 410. The oxygen introduced into the pipe 422 from the oxygen supply facility 240 is adjusted to a predetermined pressure (a pressure exceeding a fourth pressure described later, for example, 2.31 MPa) by a pressure adjustment valve (not shown).

  Further, a second cooling pipe 412 is provided on the outer periphery of the second cylinder 410 in the same manner as the first cylinder 210, and the second cooling pipe 412 has a refrigerant (for example, cooled by the refrigerator 230 through the pipe 424). Alcohol aqueous solution, condensable refrigerant (R-404A) and the like. Thereby, the inside of the second cylinder 410 can be maintained at a predetermined temperature (for example, about 2 ° C.). In addition, the refrigerant heated by cooling the inside of the second cylinder 410 (heat exchanged refrigerant) is sent from the second cooling pipe 412 to the refrigerator 230 through the pipe 426 and cooled again in the refrigerator 230. It becomes.

(Clathrate manufacturing method)
Next, a method for producing ozone (mixed gas) clathrate using the gas pressure increasing unit 110 will be described. FIG. 3 is a flowchart for explaining the processing flow of the clathrate manufacturing method according to the present embodiment. As shown in FIG. 3, the clathrate manufacturing method includes an introducing step S110, a first boosting step S120, a second boosting step S130, a sending step S140, and a pressure reducing step S150. In the initial stage of operation, the first cylinder 210 is filled with water, and the second cylinder 410 is filled with oxygen (for example, about 0.38 MPa to 0.39 MPa). It is assumed that the valves 220a, 244a, 252a, 420a, and 422a are closed. Hereinafter, the process in each process is explained in full detail.

(Introduction step S110)
First, the control unit (not shown) opens the valve 244a provided in the pipe 244 and opens the valve 420a provided in the pipe 420. Then, due to the differential pressure between the first cylinder 210 and the second cylinder 410, the water in the first cylinder 210 moves to the second cylinder 410 through the pipe 222, and the inside of the first cylinder 210 is depressurized. . As a result, ozone (0.4 MPa) is introduced into the first cylinder 210. The ozone in the first cylinder 210 is cooled to about 2 ° C. by the first cooling pipe 212.

  Further, the gas in the second cylinder 410 is pushed out by the water moved from the first cylinder 210, and after the pressure is adjusted by the pressure adjustment valve 420 b provided at the rear stage of the valve 420 a in the pipe 420, Will be sent out. With the configuration including the pressure regulating valve 420b, the introduction of ozone into the first cylinder 210 can be performed under stable pressure conditions.

(First boosting step S120)
In the first pressure increasing step S120, 0.4 MPa (first pressure) of ozone and carbon dioxide are mixed in the first cylinder 210 at a predetermined volume ratio (here, ozone: carbon dioxide = 30%: 70%). Thus, a mixed gas of 1.628 MPa (third pressure) is generated. The ultimate pressure (third pressure) of the mixed gas in the first pressurizing step S120 and the volume ratio of ozone and carbon dioxide in the mixed gas are the target pressure when the clathrate manufacturing unit 120 manufactures ozone hydrate. And determined based on the target yield.

  Specifically, the control unit closes the valve 420 a and opens the valve 252 a provided in the pipe 252 to start introducing carbon dioxide into the first cylinder 210. Then, 4.7 MPa (second pressure) of carbon dioxide cooled to an average of −46 ° C. (second temperature) by the expansion valve 258 is introduced into the first cylinder 210.

  Here, by introducing carbon dioxide into the first cylinder 210, the ozone is compressed and the temperature of the ozone rises, but the temperature rise of the ozone can be suppressed by the cold heat of carbon dioxide (−46 ° C.). It becomes possible to prevent decomposition of ozone.

(Second boosting step S130)
When the pressure in the first cylinder 210 reaches the third pressure, the mixed gas is further increased to the fourth pressure (for example, 2.3 MPa).

  Specifically, the control unit closes the valves 244a and 252a and opens the valve 422a provided in the pipe 422. If it does so, the water in the 2nd cylinder 410 will be extruded by the oxygen sent out from the oxygen supply equipment 240, and will be introduce | transduced into the 1st cylinder 210 via the piping 222. FIG. The mixed gas in the first cylinder 210 is increased to the fourth pressure by the water moved from the second cylinder 410.

  In the first cylinder 210, the mixed gas is compressed by water (water pressure) and the temperature rises, but is maintained at about 2 ° C. by the first cooling pipe 212. Thereby, decomposition | disassembly of ozone can be prevented.

(Sending process S140)
The control unit opens the valve 220a provided in the pipe 220. Then, the mixed gas having the fourth pressure (2.3 MPa) and the third temperature (about 2 ° C.) generated in the first cylinder 210 is supplied to the clathrate manufacturing unit 120.

(Drop pressure process S150)
When the water surface of the first cylinder 210 reaches a predetermined threshold, the control unit closes the valves 220a and 422a and opens the valve 420a. If it does so, the water of the 1st cylinder 210 will move to the 2nd cylinder 410, and the gas in the 2nd cylinder 410 will be sent to the dezonizer 430. Further, as described above, due to the configuration including the pressure regulating valve 420b, the gas in the second cylinder 410 is excessively depressurized, and ozone and carbon dioxide dissolved in water by being pressurized in the first cylinder 210. The situation of being lost excessively can be avoided.

  In the pressure drop process S150, the water levels of the first cylinder 210 and the second cylinder 410 are determined so that the pressure in the first cylinder 210 is less than the first pressure.

  As described above, according to the clathrate manufacturing method according to the present embodiment, by the configuration in which the cooled carbon dioxide is introduced into the first cylinder 210 containing ozone and the ozone is compressed, the ozone is compressed. The temperature rise that occurs can be suppressed, and ozone decomposition can be prevented. In this way, it is possible to generate a raw material gas whose pressure is increased to a desired pressure in the clathrate production unit 120 while preventing decomposition of ozone.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  For example, in the said embodiment, ozone was mentioned as an example as 1st gas and the carbon dioxide was mentioned as an example as 2nd gas. However, there is no limitation to the first gas and the second gas, and the clathrate manufacturing apparatus 100 only needs to be able to manufacture a clathrate that includes at least the first gas.

  Moreover, in the said embodiment, in addition to 1st pressure | voltage rise process S120, the structure which performs 2nd pressure | voltage rise process S130 was mentioned as an example, and was demonstrated. However, when the clathrate manufacturing unit 120 can boost the pressure to a desired pressure only by the first boosting step S120, the second boosting step S130 may be omitted.

  Moreover, in the said embodiment, the clathrate manufacturing apparatus 100 comprised including the one gas pressure | voltage rise unit 110 was mentioned as an example, and was demonstrated. However, the number of gas boosting units 110 is not limited, and a plurality of gas boosting units 110 may be provided to continuously boost the source gas.

  INDUSTRIAL APPLICABILITY The present invention can be used for a clathrate production method for producing a clathrate containing a gas as a guest substance.

S110 Introduction Step S120 First Boosting Step S130 Second Boosting Step

Claims (5)

A clathrate production method for producing a clathrate comprising a first gas as a guest substance,
Storing the first gas in a storage tank at a first pressure and a first temperature;
A second gas having a second pressure higher than the first pressure and a second temperature lower than the first temperature is introduced into the storage tank, and a third pressure that is higher than the first pressure and lower than the second pressure; A step of mixing the first gas and the second gas to generate a mixed gas;
A clathrate manufacturing method comprising:   The step of generating the mixed gas is a predetermined third temperature that is higher than an upper limit value of the generation temperature of the clathrate enclosing the second gas, and suppresses a temperature rise of the first gas to suppress the first gas. The clathrate manufacturing method according to claim 1, wherein the first gas and the second gas are mixed so that the pressure is 3 pressures.   The method for producing a clathrate according to claim 1, further comprising a step of increasing the pressure of the mixed gas generated in the step of generating the mixed gas.   The clathrate manufacturing method according to claim 1, wherein the first gas is ozone.   The clathrate manufacturing method according to claim 4, wherein the second gas is carbon dioxide.

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