Gas processing system

Abstract

It enables the removal of water vapor with a simple configuration. [Solution] A gas treatment system according to one aspect of the present disclosure comprises: a carbon dioxide separation device having a separation membrane that has the function of separating carbon dioxide from a gas containing carbon dioxide; a negative pressure generating device that generates negative pressure in a passage communicating from a downstream chamber of the separation membrane; and a water separation device provided on the passage that separates water from the gas containing carbon dioxide that has passed through the separation membrane using the negative pressure generated by the negative pressure generating device, and outputs the water and the gas containing carbon dioxide separately.

Description

Technical Field

[0001] The present invention relates to a gas treatment system.

Background Art

[0002] In order to suppress the emission of greenhouse gases, there is a carbon dioxide recovery system. In recent years, as one of the methods of the carbon dioxide recovery system, a membrane separation method has been proposed. In the membrane separation method, water vapor contained in the exhaust gas has passed through the separation membrane. Therefore, in the carbon dioxide recovery system using the membrane separation method, a pressure difference generating device for generating a pressure difference between the upstream chamber and the downstream chamber of the separation membrane, and a dehumidifying device on the gas path through which the permeated gas flows from the downstream chamber of the separation membrane are provided, so that water vapor is removed and carbon dioxide can be recovered (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the prior art such as Patent Document 1, since cooling water is circulated to dehumidify with a dehumidifying device, a cooling mechanism such as a cooling water circulation pump and a radiator is required, so the dehumidifying mechanism may be enlarged.

[0005] One aspect of the present invention aims to provide a gas treatment system that can remove water vapor with a simple configuration.

Means for Solving the Problems

[0006] A gas treatment system according to one aspect of the present invention comprises a carbon dioxide separation device having a separation membrane that has the function of separating carbon dioxide from a gas containing carbon dioxide; a negative pressure generating device that generates negative pressure in a passage communicating from a downstream chamber of the separation membrane; and a water separation device provided on the passage that separates water from the gas containing carbon dioxide that has passed through the separation membrane using the negative pressure generated by the negative pressure generating device, and outputs the water and the gas containing carbon dioxide separately. [Effects of the Invention]

[0007] According to one aspect of the present invention, the negative pressure generated by the negative pressure generator separates moisture from the carbon dioxide-containing gas flowing from the downstream chamber, thereby enabling the removal of water vapor with a simple configuration. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the general configuration of the carbon dioxide capture system according to the first embodiment. [Figure 2] This is a schematic diagram showing the general configuration of a carbon dioxide capture system according to the second embodiment. [Figure 3] This is a schematic diagram showing the general configuration of a carbon dioxide capture system according to the third embodiment. [Figure 4] This figure shows the relationship between the exhaust speed of the negative pressure generating device according to the third embodiment and the achievable vacuum level in the space from the downstream chamber of the separation membrane to the suction channel. [Figure 5] This figure shows the relationship between the temperature of the heat transfer section and the achievable vacuum level according to the third embodiment. [Figure 6] This figure shows the relationship between saturated water vapor pressure, the temperature of the heat transfer section according to this embodiment, and the water vapor concentration. [Figure 7] This is a flowchart showing the processing procedure by the control device according to the third embodiment. [Figure 8] This is a schematic diagram showing the general configuration of a carbon dioxide capture system according to the fourth embodiment. [Figure 9]This is a schematic diagram showing the general configuration of a carbon dioxide capture system according to the fifth embodiment. [Figure 10] This is a flowchart showing the processing procedure by the control device according to the fifth embodiment. [Figure 11] This figure shows the control before starting operation in the carbon dioxide capture system according to the sixth embodiment. [Figure 12] This is a schematic diagram showing the general configuration of the water separation device of the carbon dioxide recovery system according to the seventh embodiment. [Figure 13] This is a schematic diagram showing the general configuration of a water separation device for a carbon dioxide recovery system according to a modified example of the seventh embodiment. [Figure 14] This figure shows the control before operation starts and after operation ends in the control device according to the seventh embodiment. [Figure 15] This is a schematic diagram showing the general configuration of a water separation device in a carbon dioxide recovery system according to the eighth embodiment. [Figure 16] This is a schematic diagram showing the general configuration of a water separation device in a carbon dioxide recovery system according to Modification 1 of the 8th embodiment. [Figure 17] This is a schematic diagram showing the general configuration of a water separation device in a carbon dioxide recovery system according to a modified example 2 of the eighth embodiment. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings. Furthermore, the embodiments described below are illustrative and not limiting to the invention, and not all features or combinations thereof described in the embodiments are necessarily essential to the invention. In addition, identical or corresponding components in each drawing are denoted by the same or corresponding reference numerals, and their descriptions may be omitted.

[0010] (First Embodiment) FIG. 1 is a schematic diagram showing the schematic configuration of a carbon dioxide recovery system (an example of a gas treatment system) according to the first embodiment. The carbon dioxide recovery system 1 according to the first embodiment includes an exhaust gas emission source 110, a heat and moisture removal device 120, a dust removal device 130, a separation device 140, a water separation device 150, a negative pressure generation device 160, and a carbon dioxide recovery device 170.

[0011] The exhaust gas emission source 110 may have a configuration that emits exhaust gas containing carbon dioxide. For example, it may be a combustion mechanism that generates thermal energy by burning fuel using air. The fuel may be any combustible medium, and for example, light oil, gasoline, or combustible gas may be used. In the exhaust gas emission source 110, by burning the fuel, a gas (hereinafter also referred to as exhaust gas) in which carbon dioxide, moisture, nitrogen, and a predetermined compound are mixed is generated, and the exhaust gas is output to the heat and moisture removal device 120.

[0012] The heat and moisture removal device 120 removes heat from the exhaust gas input from the exhaust gas emission source 110 and removes a part of the moisture contained in the exhaust gas. The heat and moisture removal device 120, for example, removes heat from the exhaust gas. When the exhaust gas is cooled to a predetermined temperature, the water vapor contained in the exhaust gas liquefies. Then, the heat and moisture removal device 120 removes the liquefied moisture from the exhaust gas. The predetermined temperature may be any temperature, for example, the room temperature of the room where the heat and moisture removal device 120 is provided. The heat and moisture removal device 120 outputs the exhaust gas with a part of the moisture removed to the dust removal device 130.

[0013] The dust removal device 130 is a mechanism for removing dust (for example, a predetermined compound) and dust generated by combustion in the exhaust gas emission source 110 from the exhaust gas, and for example, a dust-proof filter or the like is provided. The dust removal device 130 outputs the exhaust gas from which dust and dust have been removed by the mechanism to the separation device 140.

[0014] The separation device 140 includes a separation membrane 141, an upstream chamber 142 partitioned by the separation membrane 141, and a downstream chamber 143. The exhaust gas output from the dust removal device 130 is discharged to the upstream chamber 142 side.

[0015] The separation membrane 141 has the function of separating carbon dioxide from the exhaust gas by allowing the carbon dioxide contained in the exhaust gas discharged into the upstream chamber 142 to pass through. The separation membrane 141 can be any membrane capable of separating carbon dioxide, and may be an accelerated transport membrane, an organic polymer membrane, an inorganic material membrane, or a liquid membrane.

[0016] Specifically, the carbon dioxide contained in the exhaust gas flowing into the upstream chamber 142 permeates the separation membrane 141 due to the pressure difference (partial pressure difference) between the upstream chamber 142 and the downstream chamber 143 generated by the negative pressure generator 160 (described later), and the gas containing carbon dioxide flows into the downstream chamber 143.

[0017] Of the exhaust gas that flows into the upstream chamber 142, the exhaust gas that does not permeate the separation membrane 141 (also referred to as unpermeated gas) is discharged through the exhaust flow path 144 connected to the upstream chamber 142.

[0018] The gas containing carbon dioxide that has permeated through the separation membrane 141 (hereinafter also referred to as permeate gas) is discharged to the water separation device 150 via the permeate gas channel 145.

[0019] By the way, when the separation membrane 141 allows carbon dioxide to pass through the exhaust gas, it also allows water vapor contained in the exhaust gas to pass through.

[0020] In other words, conventional membrane separation systems for carbon dioxide separation and recovery also recover water vapor. When recovering carbon dioxide, it is preferable to remove as much water vapor as possible to increase the concentration of carbon dioxide. On the other hand, if the configuration for removing water vapor becomes large, it becomes difficult to secure installation space.

[0021] Furthermore, when a dehumidifier is installed to remove water vapor, if the dehumidifier uses a mechanism that cools the exhaust gas by circulating cooling water, it is necessary to consume power to operate the cooling mechanism, such as the cooling water circulation pump and radiator.

[0022] Therefore, the carbon dioxide recovery system 1 according to this embodiment is equipped with a water separator 150 that uses less power and saves space compared to conventional systems.

[0023] The water separator 150 is configured to remove moisture from the permeate gas flowing in from the separator 140, and is connected to the negative pressure generator 160 via an intake channel 161 and an exhaust channel 162.

[0024] The negative pressure generator 160 is a device that generates negative pressure in a flow path communicating from the downstream chamber 143 of the separation membrane 141, and for example, a depressurizing pump is used. In this embodiment, the negative pressure generator 160 performs depressurization control on the permeate gas present in the downstream chamber 143 of the separation membrane 141, the permeate gas flow path 145, the heat transfer section 151 of the water separation device 150, and the suction flow path 161. This creates a pressure difference (partial pressure difference) between the upstream chamber 142 and the downstream chamber 143.

[0025] The permeate gas flowing in from the downstream chamber 143 and present in the water separator 150 undergoes adiabatic expansion due to the pressure reduction control by the negative pressure generator 160. This adiabatic expansion of the permeate gas present in the water separator 150 and the suction channel 161 cools the surroundings by absorbing heat from them.

[0026] Meanwhile, the negative pressure generator 160 adiabatically compresses the permeate gas taken in from the water separator 150 via the suction channel 161, and discharges the adiabatically compressed permeate gas through the discharge channel 162. The permeate gas discharged from the discharge channel 162 has a higher temperature than the permeate gas present in the suction channel 161 due to adiabatically compressed air. The degree of adiabatically compressed air may be determined according to the embodiment; for example, the pressure of the permeate gas after adiabatically compressed air may be set to be equivalent to atmospheric pressure.

[0027] The water separator 150 according to this embodiment includes a heat transfer section 151. The heat transfer section 151 is configured to exchange heat between the permeate gas, which is adiabatically expanded by the negative pressure generator 160 and flows in from the permeate gas flow path 145, and the adiabatically compressed permeate gas discharged from the negative pressure generator 160. The configuration of the heat transfer section 151 can be any configuration as long as heat exchange is possible, and specific examples of configurations will be described in the embodiments described later.

[0028] The heat transfer section 151 generates water by cooling and condensing the water vapor contained in the permeate gas through heat exchange between the adiabatically expanded permeate gas and the adiabatically compressed permeate gas.

[0029] In this way, the water separator 150 separates the water vapor contained in the permeate gas as moisture from the permeate gas. The moisture separated from the permeate gas is discharged through the liquid recovery passage 152.

[0030] Meanwhile, the permeate gas from which the water has been separated is recovered by the carbon dioxide recovery device 170 via the carbon dioxide recovery channel 153.

[0031] As described above, the water separator 150 according to this embodiment separates water from the carbon dioxide-containing permeate gas flowing in from the downstream chamber 143 using the negative pressure generated by the negative pressure generator 160, and outputs the water and the permeate gas (gas containing carbon dioxide) from which the water has been separated. It should be noted that this embodiment is not limited to a configuration in which heat exchange is performed in the heat transfer section 151, but any configuration that uses the power generated by the negative pressure generator 160 to separate water from the carbon dioxide-containing permeate gas is acceptable.

[0032] Furthermore, the permeable gas channel 145 according to this embodiment is provided so as to be able to transfer heat from the heat transfer section 151. For example, the outer periphery of the permeable gas channel 145 is formed of a predetermined metal that conducts heat easily, and the outer periphery of the permeable gas channel 145 is connected to the heat transfer section 151. In this embodiment, the permeable gas heated by adiabatic compression transfers heat to the permeable gas channel 145 via the heat transfer section 151. Since the inside of the permeable gas channel 145 is heated, condensation within the permeable gas channel 145 can be suppressed.

[0033] The carbon dioxide recovery system (an example of a gas treatment system) 1 according to this embodiment, by having the above-described configuration, can cool and condense water vapor contained in the permeate gas and separate the water without using an external cooling mechanism. Therefore, the carbon dioxide recovery system 1 can efficiently remove water vapor contained in exhaust gas.

[0034] In this embodiment, the water vapor removal is performed using a heat removal / dehumidification device 120, which is a pre-process of the carbon dioxide separation device 140, and a water separation device 150, which is a post-process of the carbon dioxide separation device 140.

[0035] Incidentally, if water vapor is removed from the exhaust gas only in the pre-processing stage where carbon dioxide is separated, a configuration with high dehumidification efficiency is required, which means the dehumidifier will be larger and the power required to operate it will also be greater. On the other hand, if water vapor is not removed from the exhaust gas in the pre-processing stage, condensation may occur when the exhaust gas cools.

[0036] Therefore, in this embodiment, the heat removal / dehumidification device 120 is configured to dehumidify the gas (exhaust gas or permeate gas) flow path up to the water separation device 150 to an extent that prevents condensation. The water separation device 150 is configured to cool and remove the water vapor that has become highly concentrated after permeating the separation membrane 141 of the separation device 140. By removing water vapor in these two stages, condensation on the flow path can be suppressed, and efficient removal of water vapor can be achieved.

[0037] (Second embodiment) The carbon dioxide capture system according to the second embodiment is an embodiment in which a new configuration is added to the carbon dioxide capture system 1 according to the first embodiment.

[0038] Figure 2 is a schematic diagram showing the general configuration of a carbon dioxide recovery system (an example of a gas treatment system) according to the second embodiment. The carbon dioxide recovery system 2 of the second embodiment has a configuration in which a reheat device 210 is added to the carbon dioxide recovery system 1 of the first embodiment. Among the components of the carbon dioxide recovery system 2 of the second embodiment, components that are the same as those of the carbon dioxide recovery system 1 of the first embodiment are assigned the same reference numerals and their descriptions are omitted.

[0039] In the carbon dioxide recovery system 2 according to the second embodiment, a reheating device 210 is provided on the carbon dioxide recovery channel 153 through which the permeate gas, from which water has been separated, passes from the water separator 150 to the carbon dioxide recovery device 170. The reheating device 210 is connected to the upstream chamber 142 of the separator 140 via an impermeable channel 211.

[0040] The reheating device 210 has a heat exchange function that causes heat exchange to occur between the permeate gas from which moisture has been separated (containing carbon dioxide) and the impermeable gas flowing in from the impermeable channel 211. Through this heat exchange function, the reheating device 210 raises the temperature of the permeate gas from which moisture has been separated (containing carbon dioxide) compared to before the heat exchange, using the waste heat from the impermeable gas flowing in from the impermeable channel 211.

[0041] The reheating device 210 discharges the unpermeated gas after heat exchange through the exhaust passage 212.

[0042] Therefore, the carbon dioxide recovery system 2 of the second embodiment, by including a reheating device 210, can reduce the relative humidity of the permeate gas from which moisture has been separated, thereby preventing condensation in the carbon dioxide recovery channel 153.

[0043] (Third embodiment) The carbon dioxide capture system according to the third embodiment is an embodiment in which a new configuration is added to the carbon dioxide capture system 2 according to the second embodiment.

[0044] Figure 3 is a schematic diagram showing the general configuration of a carbon dioxide capture system (an example of a gas treatment system) according to the third embodiment. The carbon dioxide capture system 3 of the third embodiment is newly equipped with pressure sensors 311, 312, and 318, dew point meters 313, 315, 316, and 317, a temperature sensor 314, and a control device 350, in addition to the carbon dioxide capture system 2 of the second embodiment. Among the components of the carbon dioxide capture system 3 of the third embodiment, components that are the same as those of the carbon dioxide capture system 2 of the second embodiment are assigned the same reference numerals and their description is omitted.

[0045] The control device 350 adjusts the negative pressure generated by the negative pressure generator 160 based on the dew point temperature detected by dew point meters (examples of detection units) 313, 315, 316, and 317 installed between the downstream chamber 143 of the separation membrane 141 and the carbon dioxide recovery device 170 that recovers the carbon dioxide-containing permeate gas output from the water separation device 150, and the temperature of the heat transfer unit 151 detected by the temperature sensor 314.

[0046] For example, the control device 350 controls the negative pressure generator 160 so that the water vapor concentration of the permeate gas from which moisture has been separated by the water separator 150 becomes a predetermined required value. The required value is determined according to the embodiment, such as the power of the negative pressure generator 160 and the concentration of carbon dioxide to be recovered by the carbon dioxide recovery device 170.

[0047] Figure 4 shows the relationship between the exhaust speed of the negative pressure generator 160 according to this embodiment and the achievable vacuum level in the space from the downstream chamber 143 of the separation membrane 141 to the suction channel 161. The line 1401 shown in Figure 4 indicates the required exhaust speed according to the achievable vacuum level.

[0048] In other words, the control device 1400 controls the rotation speed of a motor (not shown) inside the negative pressure generator 160 so that it is equal to or greater than the exhaust speed corresponding to the target vacuum level, in accordance with the change (achievement) of the target vacuum level from atmospheric pressure P0. This allows for a decrease in the pressure [Pa] indicated by the target vacuum level, or in other words, an increase in the degree of vacuum.

[0049] Figure 5 shows the relationship between the temperature of the heat transfer section 151 and the achievable vacuum [Pa] according to this embodiment. As shown by line 1501, the pressure indicated by the achievable vacuum decreases, or in other words, the degree of vacuum increases, as the permeating gas absorbs heat from the surroundings through depressurization and expansion, thus decreasing the temperature of the heat transfer section 151.

[0050] Figure 6 shows the relationship between saturated water vapor pressure, the temperature of the heat transfer section 151 according to this embodiment, and the water vapor concentration.

[0051] Line 1601 shows the relationship between saturated water vapor pressure and the temperature of the heat transfer unit 151. As shown by line 1601, the lower the temperature of the heat transfer unit 151, the lower the saturated water vapor pressure. Therefore, as shown by line 1602, the lower the temperature of the heat transfer unit 151, the lower the water vapor concentration in the permeate gas. In other words, the water vapor concentration in the permeate gas can be adjusted by adjusting the temperature of the heat transfer unit 151. To adjust the temperature of the heat transfer unit 151, the exhaust speed, or in other words, the motor rotation speed of the negative pressure generator 160, should be adjusted.

[0052] The control device 350 calculates the water vapor concentration based on the dew point temperature detected by the dew point meters (an example of detection units) 313, 315, and 316, and the temperature of the heat transfer unit 151 detected by the temperature sensor 314. The method for calculating the water vapor concentration is not limited to a calculation method based on the dew point temperature and temperature, and any method may be used.

[0053] The control device 350 controls the rotation speed of the motor inside the negative pressure generator 160 so that the water vapor concentration after separation by the water separator 150 matches the required water vapor value.

[0054] Next, the processing procedure in the control device 350 will be described. Figure 7 is a flowchart showing the processing procedure by the control device 350 according to this embodiment.

[0055] In this embodiment, the carbon dioxide recovery system 3 starts adjusting the water vapor concentration of the permeate gas (S1701). The control device 350 calculates the water vapor concentration θaq1 of the permeate gas after the water has been separated by the water separator 150, based on the dew point temperature detected by the dew point meter (an example of a detection unit) 316 and the temperature of the heat transfer unit 151 detected by the temperature sensor 314 (S1702).

[0056] The control device 350 determines whether the condition |water vapor concentration θaq1 - required water vapor concentration θaq_req|>0 is met (S1703). If the control device 350 determines that the condition "|water vapor concentration θaq1 - required water vapor concentration θaq_req|>0" is not met, in other words, that the detected water vapor concentration θaq1 matches the required value θaq_req (S1703: NO), it terminates the process, considering the adjustment of the water vapor concentration to be complete.

[0057] On the other hand, if the control device 350 determines that the condition "|water vapor concentration θaq1 - required water vapor concentration θaq_req|>0" is met (S1703:YES), it determines whether "water vapor concentration θaq1 > required water vapor concentration θaq_req" (S1704).

[0058] If the control device 350 determines that "water vapor concentration θaq1 > required water vapor concentration θaq_req" (S1704: YES), it controls the motor rotation speed of the negative pressure generator 160 to increase compared to before the determination (S1705). The amount of increase in motor rotation speed can be determined according to the embodiment.

[0059] On the other hand, if the control device 350 determines that "water vapor concentration θaq1 > required water vapor concentration θaq_req" is not true (S1704: NO), it controls the motor rotation speed of the negative pressure generator 160 to decrease compared to before the determination (S1706). The amount of reduction in motor rotation speed can be determined according to the embodiment.

[0060] Subsequently, the control device 350 calculates the water vapor concentration θaq2 based on the dew point temperature detected by the dew point meters (an example of a detection unit) 313 and 315 and the temperature of the heat transfer unit 151 detected by the temperature sensor 314 (S1707).

[0061] The control device 350 determines whether the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req| = 0 is met (S1708).

[0062] If the control device 350 determines that the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req|=0 is not met (S1708: NO), it replaces the water vapor concentration θaq2 with the water vapor concentration θaq1 (S1709) and processes again from S1704.

[0063] On the other hand, the control device 350 terminates the process if it determines that the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req| = 0 is met (S1708: YES).

[0064] The control device 350 according to this embodiment can adjust the water vapor concentration by performing the control described above.

[0065] Furthermore, the control device 350 according to this embodiment may control the configuration within the carbon dioxide recovery system 3 according to the detection results of various sensors. For example, the control device 350 may adjust the relative humidity of the permeate gas from which moisture has been separated, which flows to the reheating device 210, according to the detection results of the dew point meters 316 and 317. Any method can be used to adjust the relative humidity; for example, the amount of unpermeate gas flowing in from the unpermeate channel 211 may be controlled.

[0066] Furthermore, the control device 350 may control the rotation speed of the motor inside the negative pressure generator 160 according to the pressure difference detected by the pressure sensors 311, 312, and 318.

[0067] The carbon dioxide capture system 3 according to this embodiment, by having the above-described configuration, can capture carbon dioxide at a desired concentration by adjusting the water vapor concentration. Therefore, it is possible to improve the accuracy of carbon dioxide capture.

[0068] This embodiment shows an example of the sensor configuration of the carbon dioxide capture system 3, and is not limited to this sensor configuration. The carbon dioxide capture system 3 according to this embodiment only needs to be equipped with sensors capable of detecting water vapor concentration and capable of executing the processing procedure shown in Figure 7.

[0069] (Fourth embodiment) The carbon dioxide recovery system according to the fourth embodiment is an example in which the permeate gas flow path connecting the separation device 140 and the water separation device 150 is modified compared to the carbon dioxide recovery system 3 according to the third embodiment.

[0070] Figure 8 is a schematic diagram showing the general configuration of a carbon dioxide capture system (an example of a gas treatment system) according to the fourth embodiment. The carbon dioxide capture system 3 of the fourth embodiment is equipped with a permeate gas flow path 401 that has a different shape from the carbon dioxide capture system 3 of the third embodiment. Among the components of the carbon dioxide capture system 4 of the fourth embodiment, components that are the same as those of the carbon dioxide capture system 3 of the third embodiment are assigned the same reference numerals and their description is omitted.

[0071] As shown in Figure 8, the carbon dioxide recovery system 4 indicates the height of the inlet or outlet for the permeate gas relative to the ground level GL. As shown in Figure 8, the height of the liquid recovery port 414 is GL+A, the height of the liquid discharge port 413 is GL+B, the height of the inlet 412 is GL+C, and the height of the outlet 411 is GL+D. The heights are in the order D>C>B>A. The inlet 412 is configured to connect the permeate gas flow path 401 and the heat transfer section 151. The permeate gas flowing in from the inlet 412 then flows into the negative pressure generator 160 via the heat transfer section 151.

[0072] As shown in Figure 8, the outlet 411 in the downstream chamber 143 of the separation device 140, which discharges the permeate gas to the water separator 150, is located at a higher position than the inlet 412 into which the permeate gas flows into the water separator 150.

[0073] The permeate gas channel 401 connecting the outlet 411 to the inlet 412 is inclined downward from the separation device 140 to the water separation device 150. Therefore, the permeate gas can easily move from the separation device 140 to the water separation device 150. Furthermore, even if condensation occurs in the permeate gas channel 401, the water droplets can be guided to the water separation device 150.

[0074] The water and other substances separated by the water separator 150 are discharged from the liquid outlet 413, which is lower than the inlet 412.

[0075] Furthermore, the carbon dioxide recovery system 4 is equipped with a flow path 402 that allows the water separated by the water separator 150 to flow out from a liquid outlet 413 provided in the water separator 150 to a liquid recovery port 414 provided below the liquid outlet 413.

[0076] Therefore, the carbon dioxide recovery system 4 according to this embodiment, by having the above-described configuration, can suppress the backflow of moisture (droplets) and efficiently recover droplets (moisture).

[0077] (Fifth embodiment) The carbon dioxide capture system according to the fifth embodiment is an embodiment in which a new configuration is added to the carbon dioxide capture system 3 according to the third embodiment. The carbon dioxide capture system according to the fifth embodiment may also have the structure shown in the carbon dioxide capture system 4 according to the fourth embodiment.

[0078] Figure 9 is a schematic diagram showing the general configuration of a carbon dioxide recovery system (an example of a gas treatment system) according to the fifth embodiment. The carbon dioxide recovery system 5 of the fifth embodiment is newly equipped with bypass channels 511 and 512, a control valve 501, and a control device 550 in addition to the carbon dioxide recovery system 3 of the third embodiment. Furthermore, a pressure sensor 319 is newly provided to detect the pressure of the permeate gas discharged from the negative pressure generator 160. Among the components of the carbon dioxide recovery system 5 of the fifth embodiment, components that are the same as those of the carbon dioxide recovery system 3 of the third embodiment are assigned the same reference numerals and their explanation is omitted.

[0079] Incidentally, conventionally, some negative pressure generating devices do not allow for precise adjustment of the negative pressure based on motor speed, etc. When such a negative pressure generating device is installed in a carbon dioxide recovery system, it is difficult to control the negative pressure generating device to match the required water vapor concentration. Therefore, in the carbon dioxide recovery system 5 according to this embodiment, we will describe a case in which the discharge flow rate of the permeate gas is controlled by performing spillback control using bypass passages 511 and 512 and a control valve 501.

[0080] The carbon dioxide recovery system 5 shown in Figure 9 is provided with bypass channels 511 and 512 connecting an intake channel (example of a first channel) 161 that allows carbon dioxide-containing gas to flow from the water separator 150 to the negative pressure generator 160, and an exhaust channel (example of a second channel) 162 that allows carbon dioxide-containing gas to flow out from the negative pressure generator 160 to the water separator 150.

[0081] Furthermore, the carbon dioxide recovery system 5 is provided on the bypass channels 511 and 512 and includes an adjustable valve 501 for returning the permeate gas from the discharge channel 162 back to the intake channel 161.

[0082] The control device 550 according to this embodiment adjusts the opening degree of the control valve 501. The exhaust speed due to the reduction in pressure of the negative pressure generator 160 is adjusted by the opening degree of the control valve 501. For example, when the opening degree of the control valve 501 increases, the amount of permeate gas present in the suction passage 161 increases, so the discharge speed decreases, and when the opening degree of the control valve 501 decreases, the amount of permeate gas present in the suction passage 161 decreases, so the discharge speed increases. As shown in Figure 4, there is a correspondence between the discharge speed and the ultimate vacuum. Therefore, the control device 550 can control the ultimate vacuum by adjusting the opening degree of the control valve 501. In this way, similar to the third embodiment, the control device 550 adjusts the water vapor concentration after separation by the water separator 150 by adjusting the opening degree of the control valve 501.

[0083] Specifically, the control device 550 calculates the water vapor concentration based on the dew point temperature detected by the dew point meters (an example of detection units) 313, 315, and 316, and the temperature of the heat transfer unit 151 detected by the temperature sensor 314. The control device 550 then adjusts the opening of the control valve 501 so that the water vapor concentration after separation by the water separator 150 matches the required water vapor value.

[0084] Furthermore, in addition to adjusting the opening degree based on the water vapor concentration, the control device 550 may also adjust the opening degree of the control valve 501 based on the detection results from the pressure sensor 319 so that the amount of permeate gas discharged from the discharge channel 162 to the water separator 610 meets a predetermined standard.

[0085] Next, the processing procedure in the control device 550 will be described. Figure 10 is a flowchart showing the processing procedure by the control device 550 according to this embodiment.

[0086] The carbon dioxide recovery system 3 according to this embodiment starts an operation to adjust the water vapor concentration of the permeate gas (S2001). The control device 550 calculates the water vapor concentration θaq1 of the permeate gas after water has been separated by the water separator 150, based on the dew point temperature detected by the dew point meter (an example of a detection unit) 316 and the temperature of the heat transfer unit 151 detected by the temperature sensor 314 (S2002).

[0087] The control device 550 determines whether the condition |water vapor concentration θaq1 - required water vapor concentration θaq_req|>0 is met (S2003). If the control device 550 determines that the condition "|water vapor concentration θaq1 - required water vapor concentration θaq_req|>0" is not met, in other words, that the detected water vapor concentration θaq1 matches the required value θaq_req (S2003:NO), it terminates the process, considering the adjustment of the water vapor concentration to be complete.

[0088] On the other hand, if the control device 550 determines that the condition "|water vapor concentration θaq1 - required water vapor concentration θaq_req|>0" is met (S2003:YES), it determines whether "water vapor concentration θaq1 > required water vapor concentration θaq_req" (S2004).

[0089] If the control device 550 determines that "water vapor concentration θaq1 > required water vapor concentration θaq_req" (S2004: YES), it controls the opening of the control valve 501 to decrease compared to before the determination (S2006).

[0090] On the other hand, if the control device 550 determines that "water vapor concentration θaq1 > required water vapor concentration θaq_req" is not true (S2004: NO), it controls the opening of the control valve 501 to increase it compared to before the determination (S2005).

[0091] Subsequently, the control device 550 calculates the water vapor concentration θaq2 based on the dew point temperature detected by the dew point meters (an example of a detection unit) 313 and 315 and the temperature of the heat transfer unit 151 detected by the temperature sensor 314 (S2007).

[0092] The control device 550 determines whether the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req| = 0 is met (S2008).

[0093] If the control device 550 determines that the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req|=0 is not met (S2008:NO), it replaces the water vapor concentration θaq2 with the water vapor concentration θaq1 (S2009) and resumes processing from S2004.

[0094] On the other hand, if the control device 550 determines that the condition |water vapor concentration θaq2 - required water vapor concentration θaq_req|=0 is met (S2008:YES), it terminates the process.

[0095] The control device 550 according to this embodiment can adjust the water vapor concentration by performing the control described above. The carbon dioxide recovery system 5 can recover carbon dioxide at a desired concentration by adjusting the water vapor concentration. Therefore, it is possible to improve the accuracy of carbon dioxide recovery.

[0096] (Sixth embodiment) The above-described embodiment explains the control of a carbon dioxide capture system during carbon dioxide capture operation. However, when the carbon dioxide capture operation of a carbon dioxide capture system is stopped, the water vapor level in the pipes through which the permeate gas passes tends to be higher compared to when the system is in operation. Therefore, condensed water may accumulate when the system is stopped.

[0097] Therefore, in this embodiment, we will use an example of controlling the evaporation of condensed water before starting operation. In this embodiment, we will use the configuration of the carbon dioxide recovery system 3 shown in the third embodiment, but other configurations may also be used.

[0098] Figure 11 shows the control of the carbon dioxide capture system 3 according to this embodiment before the start of operation.

[0099] Line 2101 indicates whether the carbon dioxide capture system 3 is operating or stopped. As shown by line 2101, the system becomes operational at time t2, which means that carbon dioxide capture by the carbon dioxide capture system 3 begins. Time t2 is, for example, the start time of work. Before time t1, the system is stopped because it is before the start of work.

[0100] Line 2102 shows the calculated water vapor concentration (inside the pipe) present in the permeate gas of the carbon dioxide recovery system 3. For example, the control device 350 calculates the water vapor concentration in the flow path (inside the pipe) from the dew point meters 313 and 315 and the temperature sensor 314. Note that this embodiment is not limited to the example of using dew point meters 313 and 315 to calculate the water vapor concentration, and other dew point meters 316 and 317 present in the carbon dioxide recovery system 3 may be used.

[0101] As shown in line 2102, the water vapor concentration before operation is, for example, c%. The reference water vapor concentration during operation is x% (an example of a predetermined concentration). Therefore, the control device 350 controls the system so that the water vapor concentration is x% or less by the time operation starts. Note that x% is a water vapor concentration that is set in advance according to the embodiment. In the example shown in Figure 11, c% > x%.

[0102] Therefore, the control device 350 starts control to reduce the water vapor concentration from time t1, y seconds before the start of operation. In this embodiment, an evaporation purge timer is provided in the control device 350. As shown in line 2103, the evaporation purge timer is turned on at time t1, y seconds before the start of operation time t2. Note that y seconds is a number of seconds determined according to the embodiment.

[0103] Then, triggered by the evaporation purge timer being turned on, the control device 350 outputs a command to the negative pressure generator 160 to set the motor speed to R2. The motor speed R2 is set to a value higher than the motor speed R1 during operation.

[0104] Therefore, as shown in line 2102, the water vapor concentration gradually decreases from c%. When the control device 350 determines that the water vapor concentration has fallen below x%, it outputs a command to the negative pressure generator 160 to set the motor speed to R1. From then on, the negative pressure generator 160 operates at motor speed R1.

[0105] The carbon dioxide recovery system 3 according to this embodiment can be adjusted so that the water vapor concentration is x% at time t2 when the carbon dioxide recovery system 3 starts operation.

[0106] Thus, the control device 350 according to this embodiment operates the negative pressure generator 160 from a predetermined time y seconds before the start of gas processing by the carbon dioxide recovery system 3 so that the water vapor concentration in the permeate gas present in the carbon dioxide recovery system 3 becomes less than or equal to a predetermined concentration x%. Therefore, the carbon dioxide recovery system 3 according to this embodiment can suppress the accumulation of condensed water.

[0107] (Seventh Embodiment) In the carbon dioxide recovery system according to the seventh embodiment, a case is described in which the water separation device has an insulating structure that reduces external heat dissipation.

[0108] Figure 12 is a schematic diagram showing the general configuration of the water separator of the carbon dioxide recovery system according to this embodiment. The carbon dioxide recovery system 6 of the seventh embodiment has, in addition to the configuration of the carbon dioxide recovery system 3 of the third embodiment, a vacuum insulation layer 611 provided on the outer periphery of the water separator 610, and a configuration for adjusting the pressure of the vacuum insulation layer 611, which is newly provided. Furthermore, the carbon dioxide recovery system 6 is provided with a control device 650 that performs different processing from the control device 350. Among the configurations of the carbon dioxide recovery system 6 of the seventh embodiment, the same reference numerals are assigned to the same components as those of the carbon dioxide recovery system 3 of the third embodiment, and their explanation is omitted.

[0109] The water separator 610 may have the same configuration as the embodiment described above, except that a vacuum insulation layer 611 is provided on its outer periphery. In this embodiment, the heat transfer section 151 is provided with a plurality of pipes 612 for flowing permeate gas from the separator 140 to the negative pressure generator 160, and a heat transfer member 613 connected to the plurality of pipes, which applies the cold and heat transmitted from the plurality of pipes 612 to the permeate gas discharged from the outlet 162A and guides the permeate gas downward. With this configuration, the heat transfer section 151 can perform heat exchange between the permeate gas adiabatically expanded by the negative pressure generator 160 and the adiabatically compressed permeate gas discharged from the outlet 162A. Furthermore, the heat from the adiabatically compressed permeate gas discharged from the outlet 162A can warm the permeate gas flow path 145 connected via the plurality of pipes 612.

[0110] In the carbon dioxide capture system 6, a vacuum suction channel 621 is provided that connects the vacuum insulation layer 611 on the outer periphery of the water separator 610 and the negative pressure generator 160.

[0111] Furthermore, a gate valve 602 is provided on the vacuum suction channel 621, which can open and close the gap between the negative pressure generator 160 and the vacuum insulation layer 611.

[0112] Furthermore, a gate valve 601 is provided in the suction channel 161 connecting the water separator 150 and the negative pressure generator 160, allowing the connection between the water separator 150 and the negative pressure generator 160 to be opened and closed. The suction channel 161 and the vacuum suction channel 621 are configured to merge and then flow into the negative pressure generator 160.

[0113] An exhaust passage 622 for discharging gas to the outside is provided, branching off from the passage after the suction passage 161 and the vacuum suction passage 621 merge. A vacuum release valve 603 is also provided to open and close the exhaust passage 622.

[0114] The gate valve 601, gate valve 602, and vacuum breaking valve 603 according to this embodiment are electrically operated and can be opened and closed in response to an input signal.

[0115] The control device 650 adjusts the negative pressure generated by the negative pressure generator 160 based on the detection results of various sensors (e.g., pressure sensors 312 and 604) installed in the carbon dioxide capture system 6. Furthermore, the control device 650 controls the opening and closing of gate valves 601 and 602, and the vacuum breaking valve 603.

[0116] For example, when the carbon dioxide capture system 6 is shut down, the control device 650 controls the gate valves 601 and 602 to remain open. When the carbon dioxide capture system 6 is shut down, the control device 650 may control the vacuum breaking valve 603 to remain closed or to remain open.

[0117] Then, before the carbon dioxide recovery system 6 starts the operation of carbon dioxide recovery (gas processing), the control device 650 controls the gate valve 601 and the vacuum breaking valve 603 to close in order to improve the heat insulation performance of the vacuum insulation layer 611, and also controls the gate valve 602 to open, and then operates the negative pressure generator 160 to lower the pressure inside the vacuum insulation layer 611 and increase the degree of vacuum inside the vacuum insulation layer 611.

[0118] Then, when the control device 650 determines, based on the detection result of the pressure sensor 604, that a predetermined pressure has been reached, it controls the closing of the gate valve 602 and the opening of the gate valve 601. The vacuum insulation layer 611 remains closed. From this point onward, the same control as in the embodiment described above is performed.

[0119] Furthermore, the carbon dioxide recovery system 6 is provided with a gas output mechanism 605 for recovering the permeate gas from which water has been separated, and a liquid output mechanism 606 for recovering the separated water. As shown in Figure 12, the liquid output mechanism 606 may be equipped with a siphon breaker to facilitate the discharge of liquid by automatically injecting an external gas. By providing a siphon breaker, backflow due to reverse siphoning can be prevented.

[0120] Furthermore, the carbon dioxide recovery system 6 according to this embodiment does not limit the configuration of the water separator 610. Therefore, a modified example of the water separator will be described.

[0121] Figure 13 is a schematic diagram showing the general configuration of a water separator in a modified carbon dioxide recovery system according to the seventh embodiment. The carbon dioxide recovery system 6A of this modified embodiment has the same configuration as the carbon dioxide recovery system 6 of the seventh embodiment, except for the water separator 610A. Components of the carbon dioxide recovery system 6A of this modified embodiment that are the same as those of the carbon dioxide recovery system 6 of the seventh embodiment are assigned the same reference numerals and their descriptions are omitted.

[0122] The water separator 610A has a vacuum insulation layer 611A on its outer periphery. Furthermore, the water separator 610A has a permeate gas channel 145 and a suction channel 161 connected on the same side (the right side in the case of the water separator 610A shown in Figure 13).

[0123] Compared to the embodiments described above, the heat transfer section 151A of the water separator 610A has a different shape from the heat transfer section 151 because the positions of the permeate gas passage 145 and the suction passage 161 are different. Specifically, the heat transfer section 151A is formed so that a single pipe 612A reciprocates horizontally. This shape allows heat exchange to occur between the permeate gas adiabatically expanded by the negative pressure generator 160 and the adiabatically compressed permeate gas discharged from the outlet 162A, similar to the seventh embodiment.

[0124] The control device 650 can start the carbon dioxide recovery operation by the carbon dioxide recovery system 6A while improving the thermal insulation performance of the vacuum insulation layer 611A by performing the same control as in the seventh embodiment.

[0125] Furthermore, the carbon dioxide recovery system 6 is provided with a gas output mechanism 605 for recovering the permeate gas from which water has been separated, and a liquid output mechanism 606A for recovering the separated water. Thus, the liquid output mechanism 606A may have a different shape from the liquid output mechanism 606 shown in the seventh embodiment.

[0126] Next, the control by the control device 650 according to the seventh embodiment will be described. Note that the control device 650 according to a modified example of the seventh embodiment will perform the same control and will therefore not be described.

[0127] Figure 14 shows the control of the control device 650 according to this embodiment before operation starts and after operation ends.

[0128] Line 2401 indicates whether the carbon dioxide capture system 6 is operating or stopped. As shown by line 2401, the system becomes operational at time t14, which initiates carbon dioxide capture by the carbon dioxide capture system 3. Time t14 is, for example, the start time of work. Before time t11, the system is stopped because it is before the start of work. The period between time 11 and time 14 is a preparation period for operation. Also, time 15 is, for example, the end time of work. After time 15, the system is stopped.

[0129] Time 11 to time 12 is the preparation period for constructing the vacuum insulation layer 611, and time 13 to time 14 is the period for evaporating the stagnant water.

[0130] Line 2403 indicates the open / closed state of the gate valve 602 located on the vacuum suction passage 621, line 2404 indicates the open / closed state of the gate valve 601 located on the suction passage 161, and line 2407 indicates the open / closed state of the vacuum breaking valve 603.

[0131] Between times t11 and t12, the gate valve 602 on the vacuum suction passage 621 is kept open as shown by line 2403, the gate valve 601 on the suction passage 161 is kept closed as shown by line 2404, and the vacuum breaking valve 603 is kept closed as shown by line 2407. Then, the control device 650 outputs a command to the negative pressure generator 160 to set the motor speed to R3. The motor speed R3 is set to a value higher than the motor speeds R2 and R1 described above.

[0132] Therefore, as shown by line 2405, the pressure in the vacuum insulation layer 611A decreases from atmospheric pressure to z [Pa]. Note that z [Pa] is a preset pressure to ensure that the vacuum insulation layer 611A exhibits its thermal insulation performance. Then, at time t12, after the pressure in the vacuum insulation layer 611A reaches z [Pa], the control device 650 controls the system to close the gate valve 602 on the vacuum suction channel 621 and open the gate valve 601 on the suction channel 161. The vacuum release valve 603 remains closed. Subsequently, the control device 650 outputs a command to the negative pressure generator 160 to reduce the motor speed from R3 to R2. At time t13, the motor speed of the negative pressure generator 160 reaches R2.

[0133] Then, the control device 650 performs control to evaporate the condensed water between time t13 and time t14. The control between time t13 and time t14 is the same as the processing procedure shown in Figure 11 of the sixth embodiment, so its explanation is omitted.

[0134] Subsequently, when time t15 is reached, the carbon dioxide recovery operation by the carbon dioxide recovery system 6 is stopped. As shown in line 2402, the control device 650 outputs a command to the negative pressure generator 160 to reduce the motor speed to 0.

[0135] Furthermore, as shown by line 2407, the control device 650 controls the vacuum breaking valve 603 to be open. In addition, the control device 650 controls the gate valve 602 on the vacuum suction passage 621 to be open. As a result, as shown by line 2405, the pressure in the vacuum insulation layer 611 rises to atmospheric pressure. Furthermore, as shown by line 2406, the water vapor concentration gradually increases from x% to c%.

[0136] In the carbon dioxide recovery system 6 according to this embodiment, the carbon dioxide recovery operation can be started when the pressure z [Pa] of the vacuum insulation layer 611A is at a certain pressure z [Pa]. Since the vacuum insulation layer 611A has high thermal insulation performance at a certain pressure z [Pa], efficient heat exchange is possible within the water separator 610. Therefore, the carbon dioxide recovery system 6 according to this embodiment can achieve improved energy efficiency when separating water.

[0137] (Eighth embodiment) In the carbon dioxide recovery system according to the eighth embodiment, the gas output mechanism and the liquid output mechanism provided in the water separator 150 will be described.

[0138] Figure 15 is a schematic diagram showing the general configuration of a water separator in a carbon dioxide recovery system according to the eighth embodiment. The water separator 150 of this embodiment is provided with a gas output mechanism 702 and a liquid output mechanism 701 as an example of a gas-liquid separation structure. Components of the water separator 150 that are the same as those in the embodiments described above are assigned the same reference numerals and their descriptions are omitted.

[0139] As shown in Figure 15, the water separator 150 maintains a state in which water accumulates at its bottom. The liquid inlet 701A of the liquid output mechanism 701 is located below the level of the accumulated water. The liquid output mechanism 701 according to this embodiment has a liquid-seal structure that suppresses the ingress of such permeate gases.

[0140] Furthermore, the liquid output mechanism 701 is equipped with a siphon breaker to facilitate liquid discharge by automatically injecting external gas.

[0141] Furthermore, in the water separator 150, permeate gas is discharged from the discharge channel 162. The discharged permeate gas moves downward through the heat transfer section 151. The heat transfer section 151 separates moisture from the permeate gas. The separated moisture falls downward.

[0142] A shielding plate 702A is provided above the gas output mechanism 702, extending horizontally. The shielding plate 702A is provided above the gas output mechanism 702 to suppress the flow of moisture falling from the heat transfer section 151 into the carbon dioxide recovery channel 153 from the gas output mechanism 702.

[0143] Furthermore, the carbon dioxide recovery system according to this embodiment does not limit the configuration of the gas output mechanism 702 and the liquid output mechanism 701 of the water separator 150. Therefore, a modified example of the water separator will be described.

[0144] Figure 16 is a schematic diagram showing the general configuration of a water separation device in a carbon dioxide recovery system according to Modification 1 of the 8th embodiment. The water separation device 150 in this modification is provided with a mist separator 802, a gas output mechanism 801, and a liquid output mechanism 701. Of the components of the water separation device 150, the same reference numerals are assigned to components that are the same as in the 8th embodiment, and their descriptions are omitted.

[0145] The mist separator 802 is installed between the heat transfer unit 151 and the gas output mechanism 801, in other words, upstream of the gas output mechanism 801 in the flow of permeate gas discharged from the negative pressure generator 160, in order to remove fine mist (liquid droplets).

[0146] The gas output mechanism 801 has an opening 801A that allows gas moving upward, which is in a direction different from the direction in which the permeate gas flows (downward), to flow in. In this embodiment, the orientation of the opening surface of the opening 801A is not restricted to allow gas moving downward, or in other words, upward, to flow in, but may be provided to allow gas moving left and right to flow in as well.

[0147] Figure 17 is a schematic diagram showing the general configuration of a water separator in a carbon dioxide recovery system according to Modification 2 of the 8th embodiment. The water separator 150 in this modification is provided with a gas output mechanism 801 and a liquid output mechanism 901. Of the components of the water separator 150, the same reference numerals are assigned to components that are the same as those in the 8th embodiment and Modification 1 of the 8th embodiment, and their descriptions are omitted.

[0148] The liquid output mechanism 901 has a liquid inlet 901A on the bottom surface of the water separator 150. Furthermore, the liquid output mechanism 901 discharges the liquid that flows in through the inlet 901A via the liquid recovery passage 152. A siphon breaker 902 is also provided on the liquid recovery passage 152. The siphon breaker 902 facilitates the discharge of liquid by automatically injecting external gas and prevents backflow due to reverse siphon action.

[0149] <effect> In the carbon dioxide recovery system according to the above embodiment, water can be separated by heat exchange between the permeate gas adiabatically expanded by the negative pressure generator 160 and the adiabatically compressed permeate gas discharged from the negative pressure generator 160. In the above embodiment, since water can be separated using the power of the negative pressure generator for carbon dioxide recovery, without using a cooling mechanism such as a cooling water circulation pump or radiator, water vapor can be removed with a simple configuration. Furthermore, energy savings can be achieved because power for a cooling mechanism such as a cooling water circulation pump or radiator is not required.

[0150] Preferred embodiments and modifications of the present disclosure have been described above. However, the inventions of the present disclosure are not limited to the embodiments described above. Various modifications, substitutions, etc., can be applied to the embodiments described above without departing from the scope of the inventions of the present disclosure. Furthermore, each of the features described with reference to the embodiments described above may be combined as appropriate, as long as they do not conflict technically. [Explanation of symbols]

[0151] 1, 2, 3, 4, 5 Carbon dioxide capture system 140 Separation equipment 141 Separation membrane 142 Upstream room 143 Downstream room 144, 212 Exhaust passage 145, 401 Permeable gas channel 150, 610, 610A water separation equipment 151 Heat transfer section 152 Liquid recovery passage 153 Carbon dioxide capture channel 160 Negative pressure generator 161 Intake channel 162 Discharge channel 170 Carbon dioxide capture device 210 Reheating device 211 Impermeable channel 311, 312, 318, 604 Pressure Sensors 313, 315, 316, 317 Dew point meter 314 Temperature Sensor 350, 550, 650 control unit 411 Outlet 412 Inlet 413 Liquid outlet 414 Liquid recovery port 501 Control valve 511, 512 Bypass channel 601, 602 Gate valves 603 Vacuum Breaking Valve 605, 702, 801 Gas output mechanism 606, 606A, 701, 901 Liquid output mechanism 611, 611A Vacuum insulation layer 612, 612A piping 613 Heat transfer components 621 Vacuum suction channel 622 Exhaust passage 802 Mist Separator 902 Siphon breaker

Claims

1. A separation apparatus having a separation membrane that has the function of separating carbon dioxide from a gas containing carbon dioxide, A negative pressure generating device that generates negative pressure in a flow path communicating from the downstream chamber of the separation membrane, A water separation device provided on the aforementioned flow path, which uses the negative pressure generated by the negative pressure generator to separate water from the carbon dioxide-containing permeate gas that has passed through the separation membrane, and outputs the water and the permeate gas from which the water has been separated separately. A gas processing system equipped with the following features.

2. The negative pressure generating device takes in the permeate gas, which has adiabatically expanded by the negative pressure, from the downstream chamber via the water separation device, adiabatically compresses it, and then discharges it to the water separation device. The water separation device has a heat exchanger structure that cools and condenses the water vapor contained in the permeate discharged from the negative pressure generator by exchanging heat between the permeate gas, which has adiabatically expanded due to the negative pressure of the negative pressure generator flowing from the downstream chamber, and the permeate gas, which has been adiabatically compressed and discharged from the negative pressure generator. The gas treatment system according to claim 1.

3. The flow path through which the permeate gas flows from the downstream chamber to the water separator is provided so as to be able to transfer heat from the adiabatically compressed permeate gas discharged from the negative pressure generator via the heat exchanger structure. The gas treatment system according to claim 2.

4. A reheating device is provided that, by heat exchange between the permeate gas from which the water has been separated and the unpermeated flow gas that did not pass through the separation membrane, the temperature of the permeate gas from which the water has been separated is increased compared to the temperature before the heat exchange. The gas processing system according to claim 1 or 2, further comprising:

5. A control device is provided that adjusts the negative pressure generated by the negative pressure generator based on the water vapor concentration of the permeate gas from which the water has been separated by the water separation device, obtained from the detection results of the detection unit. The gas processing system according to claim 1 or 2, further comprising:

6. The outlet for discharging the permeate gas to the water separator, which is provided in the downstream chamber of the separator, is located at a higher position than the inlet for discharging the permeate gas from the downstream chamber, which is provided in the water separator. The water separation device further includes a flow path that allows the water separated by the water separation device to flow out from an outlet provided in the water separation device to a liquid recovery port provided below the outlet. The gas treatment system according to claim 1 or 2.

7. A bypass channel connecting a first channel through which the permeate gas flows from the water separator to the negative pressure generator, and a second channel through which the permeate gas is discharged from the negative pressure generator to the water separator, A control valve with an adjustable opening is provided in the bypass channel for returning the permeate gas from the second channel back to the first channel, A control device that adjusts the opening degree of the control valve based on the water vapor concentration of the permeate gas from which the water has been separated by the water separation device, obtained from the detection results of the detection unit, The gas treatment system according to claim 1 or 2, further comprising:

8. Before the start of gas processing by the gas processing system, the negative pressure generating device is operated so that the water vapor concentration in the gas present in the gas processing system is below a predetermined concentration. The gas treatment system according to claim 1 or 2.

9. A suction channel connecting the vacuum insulation layer provided on the outer periphery of the water separation device and the negative pressure generating device, A gate valve is provided in the suction channel and is capable of opening and closing the gap between the negative pressure generating device and the vacuum insulation layer, A control device that, before the start of gas processing by the gas processing system, opens the gate valve and operates the negative pressure generating device to increase the degree of vacuum in the vacuum insulation layer, and then closes the gate valve. The gas treatment system according to claim 1 or 2, further comprising:

10. The water separation device comprises a liquid output mechanism that outputs the water, and a gas output mechanism that outputs the permeate gas from which the water has been separated. The liquid output mechanism has a liquid sealing structure that suppresses the mixing of gas. The gas treatment system according to claim 1 or 2.

11. The water separation device comprises a liquid output mechanism that outputs the water, and a gas output mechanism that outputs the permeate gas from which the water has been separated, At least one of the following is provided: a mist separator provided upstream of the gas output mechanism to remove droplets in the flow of the permeate gas discharged from the negative pressure generating device; an opening in the gas output mechanism to allow the permeate gas flowing in a direction different from the direction in which the discharged permeate gas flows; and a shielding member to suppress the inflow of droplets into the opening of the gas output mechanism. The gas treatment system according to claim 1 or 2.

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