JP2022090955A - Adsorption storage system of fuel gas - Google Patents

Abstract

To provide an adsorption storage system of a fuel gas where simple heat exchange is realized and the weight increase of a system is avoided.SOLUTION: In an adsorption storage system 100 including a fuel gas storage part 11 filled with an adsorbent 111 capable of storing and discharging a fuel gas and a liquid absorbent 31 being circulated in the fuel gas storage part 11 and capable of storing and discharging carbon dioxide, the fuel gas storage part 11 and the liquid absorbent 31 are thermally and mutually connected.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fuel gas adsorption and storage system.

Patent Document 1 includes a tank filled with an adsorbent capable of adsorbing and releasing fuel gas (natural gas), and the fuel gas is released from the adsorbent in a vehicle driven by using the fuel gas supplied from the tank as fuel. It discloses a technique for heating a tank using cooling water for an engine in order to prevent a heat absorption reaction and a decrease in fuel gas release capacity associated therewith.

Japanese Unexamined Patent Publication No. 2000-146092

In a conventional vehicle such as Patent Document 1, the tank is generally arranged at the rear of the vehicle, and the engine and the radiator are generally arranged at the front of the vehicle. Therefore, when heating the tank, it is necessary to extend the cooling water pipe from the front of the vehicle to the rear of the vehicle, which not only complicates the heat exchange system but also increases the weight of the system including the cooling water. be.

Therefore, an object of the present invention is to provide a fuel gas adsorption storage system that realizes simple heat exchange and avoids weight reduction of the system.

The fuel gas adsorption storage system according to one aspect of the present invention circulates between a fuel gas storage unit filled with an adsorbent capable of storing and releasing fuel gas and a fuel gas storage unit, and can store and release carbon dioxide. It contains an absorber, and the fuel gas reservoir and the absorber are thermally connected to each other.

In the above embodiment, when the fuel gas is adsorbed on the adsorbent, heat of adsorption (heat generation) is generated, which reduces the adsorption capacity of the fuel gas. Further, when the fuel gas is released from the adsorbent, heat release (endothermic) is generated, which reduces the release capacity of the fuel gas. On the other hand, when carbon dioxide is adsorbed on the absorption liquid, heat of adsorption (heat generation) is generated, and when carbon dioxide is released from the absorption liquid, heat of release (heat absorption) is generated. Therefore, by releasing carbon dioxide when filling the fuel gas and absorbing carbon dioxide when releasing the fuel gas, the heat between the heat of adsorption generated in the fuel gas storage and the heat of release generated by the absorbing liquid It is possible to exchange heat and exchange heat between the heat released from the fuel gas storage and the heat generated by the absorbed liquid. Therefore, it is possible to suppress a decrease in the adsorption capacity when the fuel gas is adsorbed on the adsorbent and a decrease in the release capacity when the fuel gas is released from the adsorbent. Further, since the absorbent liquid and the adsorbent can directly exchange heat without using other refrigerants, the efficiency of heat exchange can be improved, and the equipment for storing the other refrigerants and carbon dioxide is not required. .. From the above, it is possible to realize simple heat exchange and avoid weighting the system.

FIG. 1 is a block diagram for briefly explaining the fuel gas adsorption storage system of the first embodiment. FIG. 2 is a graph showing the relationship between the heat of adsorbing carbon dioxide of a solid adsorbent and the pressure of carbon dioxide, and the relationship between the heat of adsorbing carbon dioxide of a liquid absorbent and the pressure of carbon dioxide. FIG. 3 shows a case where heat is exchanged between the heat of fuel gas release (heat of adsorption) and the heat of carbon dioxide adsorption (heat of release), and the solid adsorbent is filled with the fuel gas and carbon dioxide, respectively. It is a figure explaining the case. FIG. 4 is a diagram illustrating a case where heat exchange is performed between the heat of emission of fuel gas (heat of adsorption) and the heat of adsorption of carbon dioxide (heat of emission) in the first embodiment. FIG. 5 is a block diagram showing a main configuration of the fuel gas adsorption storage system of the first embodiment. FIG. 6 is a flow chart in which the fuel gas is discharged from the fuel gas storage unit and the absorption liquid absorbs carbon dioxide in the fuel gas adsorption storage system of the first embodiment. FIG. 7 shows an energy balance when the heat released when the fuel gas is discharged from the fuel gas storage unit is supplied from the outside, and is supplied from the absorption liquid to the fuel gas storage unit with the recovery rate of carbon dioxide as a parameter. It is a graph which shows the relationship which depends on the possible amount of heat and the vehicle speed, and is a circle graph which shows the ratio of the heat of adsorption of carbon dioxide, and the power consumption of the auxiliary machine which constitutes the adsorption storage system of fuel gas of 1st Embodiment. FIG. 8 is a flow chart when the fuel gas is filled in the fuel gas storage unit and carbon dioxide is released from the absorption liquid in the fuel gas adsorption storage system of the first embodiment. FIG. 9 shows a case where the amount of heat to be taken out from the fuel gas storage unit when the fuel gas is filled in the fuel gas storage unit is covered by the heat released from carbon dioxide when the recovery rate of carbon dioxide is used as a parameter. It is a graph which shows the relationship between the filling amount of fuel gas, the filling time of fuel gas, and the temperature of the fuel gas storage part. FIG. 10 is a block diagram showing a main configuration of the fuel gas adsorption storage system of the second embodiment. FIG. 11 is a block diagram showing a main configuration of the fuel gas adsorption storage system of the third embodiment. FIG. 12 is a block diagram showing a main configuration of the fuel gas adsorption storage system of the fourth embodiment. FIG. 13 is a cross-sectional view (longitudinal direction) of the fuel gas storage unit. FIG. 14 is a cross-sectional view (horizontal direction) of the fuel gas storage unit. FIG. 15 is a schematic diagram showing a fuel gas storage unit and a circulation path. FIG. 16 is a schematic diagram showing a modified example of the fuel gas storage unit and the circulation path.

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

[Outline of the first embodiment]
FIG. 1 is a block diagram for briefly explaining the fuel gas adsorption storage system 100 of the first embodiment.

The fuel gas adsorption storage system 100 (hereinafter referred to as the adsorption storage system 100) of the first embodiment is mounted on a vehicle using fuel gas (natural gas) as fuel. The adsorption storage system 100 circulates the fuel gas storage unit 11 that can be filled and released with fuel gas and the absorption liquid 31 that can be filled and released with carbon dioxide (CO ₂ ) as a refrigerant in the fuel gas storage unit 11. To prepare for.

In the fuel gas storage unit 11, the fuel gas introduction side is connected to an external supply facility (not shown) via a valve V1, and the fuel gas discharge side is connected to a fuel utilization device 9 (fuel cell, engine) via a valve V2. Has been done.

The circulation path 3 includes a circulation pump 32 that circulates the absorbing liquid 31, a gas-liquid mixing device 34 that takes in carbon dioxide from the outside and causes the absorbing liquid 31 to absorb the carbon dioxide, and an external carbon dioxide separated from the absorbing liquid 31. A first gas-liquid separation device 33 and a first gas-liquid separation device 33 are arranged.

The carbon dioxide introduction side of the gas-liquid mixing device 34 is connected to the exhaust gas discharge side of the fuel utilization device 9 via the valve V5.

The carbon dioxide discharge side of the first gas-liquid separation device 33 communicates with the outside (or the CO ₂ tank 42 (FIG. 5)) via the valve V7.

The fuel gas storage unit 11 is filled with fuel gas from an external supply facility at a predetermined pressure (for example, 3.5 [Mpa]), and the filled fuel gas is charged to the fuel utilization device 9 (fuel cell, engine) side. Can be supplied. That is, when V1 is opened with V2 closed, fuel gas is supplied and stored in the fuel gas storage unit 11, and when V2 is opened with V1 closed, the fuel gas stored in the fuel gas storage unit 11 becomes fuel. It is supplied to the equipment 9 to be used.

The fuel gas storage unit 11 is filled with an adsorbent 111 (see FIG. 5 and the like) that adsorbs and releases (desorbs) fuel gas. Therefore, when the fuel gas is supplied to the fuel gas storage unit 11, the fuel gas is adsorbed on the adsorbent 111. The amount of fuel gas adsorbed (adsorption density) varies depending on the pressure of the fuel gas in the fuel gas storage unit 11 and the temperature of the adsorbent 111.

By the way, when V2 is opened and the pressure in the fuel gas storage unit 11 decreases, the fuel gas is released from the adsorbent 111, and at that time, the adsorbent 111 generates released heat (endothermic). When the temperature of the adsorbent 111 is lowered by this released heat, the fuel gas release efficiency is lowered. Therefore, when the fuel gas is discharged from the fuel gas storage unit 11, it is necessary to supply an amount of heat corresponding to the heat released when the fuel gas is released from the adsorbent 111 from the outside.

Further, when V1 is opened and the fuel gas storage unit 11 is filled with fuel gas, the adsorbent 111 adsorbs the fuel gas, but at that time, the adsorbent 111 generates heat of adsorption (heat generation). When the temperature of the adsorbent 111 rises due to this heat of adsorption, the efficiency of adsorbing the fuel gas decreases. Therefore, when the fuel gas storage unit 11 is filled with the fuel gas, it is necessary to take out the heat of adsorption generated when the fuel gas is adsorbed on the adsorbent 111 from the outside.

The circulation path 3 is filled with an absorbent liquid 31 that absorbs and releases (desorbs) carbon dioxide. Here, the absorption amount (adsorption density) of carbon dioxide in the absorption liquid 31 changes depending on the pressure applied to the absorption liquid 31 and the temperature of the absorption liquid 31.

By the way, when V7 is opened, carbon dioxide is released from the absorption liquid 31 in the first gas-liquid separation device 33, and at that time, the absorption liquid 31 generates release heat (endothermic). When the temperature of the absorbing liquid 31 decreases due to this released heat, the carbon dioxide emission efficiency decreases. Therefore, when carbon dioxide is released from the circulation path 3, it is necessary to supply an amount of heat corresponding to the heat released when the carbon dioxide is released from the absorption liquid 31 from the outside.

Further, when V5 is opened, carbon dioxide is supplied to the circulation path 3 and the absorption liquid 31 absorbs carbon dioxide, but at that time, the absorption liquid 31 generates heat of adsorption (heat generation). When the temperature of the absorbing liquid 31 rises due to this heat of adsorption, the efficiency of adsorbing carbon dioxide decreases. Therefore, when supplying carbon dioxide to the circulation path 3, it is necessary to take out the heat of adsorption generated when the absorbing liquid 31 absorbs carbon dioxide from the outside.

Here, when the fuel utilization device 9 is a fuel cell, the fuel gas is used for the power generation reaction to generate power and emit carbon dioxide. When the fuel utilization device 9 is an engine, it burns fuel gas and emits carbon dioxide. Further, the fuel gas storage unit 11 and the circulation path 3 can exchange heat with each other from the absorbing liquid 31 which is a refrigerant.

Therefore, it is preferable to supply carbon dioxide to the circulation path 3 when the fuel gas is discharged from the fuel gas storage unit 11. As a result, the amount of heat that cancels the heat released in the fuel gas storage unit 11 can be directly received from the absorbing liquid 31, and the decrease in the releasing capacity of the fuel gas from the adsorbent 111 can be suppressed. At the same time, the adsorption heat generated when the absorption liquid 31 absorbs carbon dioxide in the circulation path 3 can be taken out by the adsorbent 111 of the fuel gas storage unit 11, and the adsorption efficiency of carbon dioxide to the absorption liquid 31 is lowered. Can be suppressed.

On the other hand, when the fuel gas storage unit 11 is filled with the fuel gas, it is preferable to release carbon dioxide from the circulation path 3. As a result, the heat of adsorption generated in the fuel gas storage unit 11 can be directly taken out by the absorbing liquid 31, and the decrease in the adsorption capacity of the fuel gas to the adsorbent 111 can be suppressed. At the same time, the adsorbent 111 of the fuel gas storage unit 11 can directly supply the amount of heat that cancels the heat released when carbon dioxide is released from the absorption liquid 31 in the circulation path 3, so that the carbon dioxide absorption liquid 31 can be directly supplied. It is possible to suppress a decrease in emission efficiency from carbon dioxide.

Examples of the adsorbent 111 include metal organic frameworks (MOF, regular porous metal complex), porous coordination polymers (Porous Coordination Polymer, PCP), activated carbon, and gas adsorbents such as zeolite. Is applied.

As the adsorbent 111 in which the heat of adsorption / release per mol of carbon dioxide is higher than the heat of adsorption / release of methane, fuel gas, etc., the adsorbent 111 such as MOF, activated charcoal, and zeolite can be mentioned. .. Many of the commonly available MOFs, such as Basolite C-300®, have high adsorption capacities for both methane and carbon dioxide, and also have high heat of carbon dioxide adsorption. Its application is preferable from the viewpoint of enabling miniaturization of the whole.

For example, when MOF is applied as the adsorbent 111, the heat of adsorption / release of methane is 12.5 [kJ / mol], and the heat of adsorption / release of carbon dioxide is 15 [kJ / mol]. Combustion of 1 mol of methane produces 1 mol of carbon dioxide. Therefore, the heat of release / heat of adsorption of 1 mol of carbon dioxide is larger than the heat of adsorption / heat of release of 1 mol of methane.

Most of the fuel gas (natural gas) is composed of methane, but it also contains a small amount of hydrocarbons such as ethane, propane, and butane. For example, the heat of adsorption of butane (n butane) is 36 [kJ / mol], but burning butane produces 4 mol of carbon dioxide. Therefore, the heat of release / heat of adsorption of 4 mol of carbon dioxide (15 × 4 = 60 [kJ / mol]) is larger than the heat of adsorption / release of 1 mol of butane (36 [kJ / mol]). It has become.

The values of heat of adsorption / heat of release of carbon dioxide, methane, and butane (n butane) are described in the non-patent document ("Heats of Adsorption for Seven Gases in Three Metal --Organic Frameworks: Systematic Comparison of Experimental and Simulation", Quoted from David Farrusseng etc, Langmuir 2009, 25 (13), 7383-7388, Published on Web 06/04/2009).

Considering the heat of adsorption / release of methane and butane, the heat of adsorption / release of ethane is about 20 [kJ / mol], and the heat of adsorption / release of propane is about 28 [kJ / mol]. Combustion of 1 mol of ethane produces 2 mol of carbon dioxide, and combustion of 1 mol of propane produces 3 mol of carbon dioxide.

Therefore, the heat of release / heat of adsorption of 2 mol of carbon dioxide (15 × 2 = 30 [kJ / mol]) is higher than the heat of adsorption / release of 1 mol of ethane (about 20 [kJ / mol]). It's getting bigger. Further, the heat of release / heat of adsorption of 3 mol of carbon dioxide (15 × 3 = 45 [kJ / mol]) is higher than the heat of adsorption / release of 1 mol of propane (about 28 [kJ / mol]). It's getting bigger.

As described above, the heat of adsorption / release of methane is 12.5 [kJ / mol], and the heat of adsorption / release of carbon dioxide is 15 [kJ / mol]. The ratio of methane in the fuel gas is about 90 [%], but the recovery rate of carbon dioxide is (12.5 [kJ / mol]) / (15 [kJ / mol]) × 100 even assuming that all methane is used. When = 83.3 [%] or more, the heat of emission / heat of carbon dioxide is larger than the heat of adsorption / heat of emission of methane.

As the absorption liquid 31, a physical absorption liquid that generates heat of absorption / release almost independently of the type of gas to be absorbed and a chemical absorption liquid in which heat of absorption / release of carbon dioxide is larger than that of other gases are applied. To. As the physical absorbent, an ionic liquid, polyethylene glycol, methanol or the like is applied. Further, as the chemical absorption liquid, an amine compound, potassium carbonate (aqueous solution) or the like is applied.

Here, assuming that the heat of adsorption / heat of release of various gases of the absorbing liquid 31 is the same as that of the adsorbent 111, the heat of adsorption / release of 1 mol of methane generated in the adsorbent 111 (12.5 [kJ / mol)). ]) Can be covered by the heat of release / heat of adsorption (15.0 [kJ / mol]) of 1 mol of carbon dioxide generated in the absorption liquid 31.

The heat of adsorption / release of 1 mol of ethane generated by the adsorbent 111 (about 20 [kJ / mol]) is converted into the heat of release / adsorption of 2 mol of carbon dioxide generated in the absorption liquid 31 (15 × 2 = 30). It can be covered by [kJ / mol]).

The heat of adsorption / release of 1 mol of propane generated by the adsorbent 111 (about 28 [kJ / mol]) is converted into the heat of release / adsorption of 3 mol of carbon dioxide generated by the absorption liquid 31 (15 × 3 = 45). It can be covered by [kJ / mol]).

The heat of adsorption / release of 1 mol of butane generated by the adsorbent 111 (36 [kJ / mol]) is converted into the heat of release / adsorption of 4 mol of carbon dioxide generated by the absorbent 31 (15 × 4 = 60 [15 × 4 = 60]. It can be covered by kJ / mol]).

As described above, even if it is assumed that the fuel gas is all methane, the recovery rate of carbon dioxide is (12.5 [kJ / mol]) / (15 [kJ / mol]) × 100 = 83.3 [%] or more. If this is the case, the heat of adsorption / release of methane generated in the adsorbent 111 can be covered by the heat of release / heat of carbon dioxide generated in the absorbing liquid 31.

FIG. 2 is a graph showing the relationship between the heat of adsorbing carbon dioxide of the solid adsorbent 111 and the pressure of carbon dioxide, and the relationship between the heat of adsorbing carbon dioxide of the liquid absorbent 31 and the pressure of carbon dioxide. ..

As shown in FIG. 2, the heat of carbon dioxide adsorption (heat released) of a solid adsorbent 111 (for example, Basolite C-300 (registered trademark)) rapidly increases as the pressure of carbon dioxide around the adsorbent 111 increases. Although it rises, it begins to saturate near 1 [Mpa] and hardly rises above 3 [Mpa].

On the other hand, the heat of adsorption (heat of release) of carbon dioxide in the liquid absorption liquid 31 (for example, an amine compound) rises almost linearly with the increase in the pressure of the carbon dioxide supplied to the absorption liquid 31, 3 [Mpa. ], It becomes larger than the heat of adsorption (heat of release) of the adsorbent 111. The difference between the heat of carbon dioxide adsorption (heat released) of the absorbing liquid 31 and the heat of carbon dioxide adsorption (heat released) of the adsorbent 111 increases with an increase in pressure at 3 [Mpa] or higher.

FIG. 3 shows a case where heat is exchanged between the heat of fuel gas release (heat of adsorption) and the heat of carbon dioxide adsorption (heat of release), and the solid adsorbent is filled with the fuel gas and carbon dioxide, respectively. It is a figure explaining the case. FIG. 4 is a diagram illustrating a case where heat exchange is performed between the heat of emission of fuel gas (heat of adsorption) and the heat of adsorption of carbon dioxide (heat of emission) in the first embodiment.

As shown in FIG. 3, when carbon dioxide is adsorbed and released by the adsorbent 111 in the same manner as the fuel gas, the adsorbent 111 is arranged in the CO ₂ storage unit 11a for storing carbon dioxide, and the fuel gas is stored. A configuration for circulating a refrigerant between the unit 11 and the CO ₂ storage unit 11a is required. In this case, in order to exchange an equal amount of heat between the CO ₂ storage unit 11a and the fuel gas storage unit 11, the CO ₂ storage unit 11a has almost the same volume as the fuel gas storage unit 11 (for example, 50 [L]]. )Is required. As a whole system, the capacity of the CO ₂ storage unit 11a (50 [L]), the capacity of the fuel gas storage unit 11 (50 [L]), and the capacity for the refrigerant separately (CO ₂ storage unit 11a and the fuel gas storage unit). The capacity of the portion separated from the portion 11) is required.

On the other hand, as shown in FIG. 4, when the absorption / release of carbon dioxide is performed by the absorption liquid 31, for example, when the pressure of the absorption liquid 31 (carbon dioxide) is 5 [Mpa], the heat of adsorption of carbon dioxide The (heat released) is about 280 [kJ / L], and the heat of carbon dioxide adsorption (heat released) of the adsorbent 111 at that time is about 170 [kJ / L]. Therefore, even if the volume of the absorbing liquid 31 is reduced by ((280-170) / 280) × 100 = 39 [%], that is, the capacity of the absorbing liquid 31 is about 30 [L], the absorbing liquid 31 and the adsorbent 111 Equal amounts of heat can be exchanged between them, and the above-mentioned refrigerant is not required. Further, for example, if the volume of the absorbing liquid 31 in the fuel gas storage unit 11 (total volume of the communication passage 52 (FIG. 13)) is 10 [L], the volume exposed from the fuel gas storage unit 11 of the circulation path 3. Is 20 [L]. From the above, as compared with the system of FIG. 3, in the present invention, the capacity of the entire system can be reduced by 30% or more.

[Main configuration of the first embodiment]
FIG. 5 is a block diagram showing a main configuration of the fuel gas adsorption storage system 100 of the first embodiment. The adsorption storage system 100 of the first embodiment is connected to a fuel utilization device 9 (fuel cell, battery) which is arranged in a vehicle and is driven by consuming fuel gas. In addition to the fuel-using device 9, a battery (not shown) and a motor (not shown) are mounted on the vehicle, the electric power generated by the fuel-using device 9 is charged to the battery, and the motor receives power from the battery to receive power from the vehicle. Drive the drive wheels. In addition, the motor generates regenerative power during deceleration, which can be charged to the battery. Of course, when the fuel utilization device 9 is an engine, it is also possible to transmit the driving force of the engine to the drive wheels.

The adsorption storage system 100 of the first embodiment stores fuel gas (natural gas) supplied from the outside, and supplies the fuel gas to the fuel gas introduction side of the fuel utilization device 9 and fuel utilization. A recovery path 2 for recovering carbon dioxide from the exhaust gas discharge side of the device 9, a circulation path 3 for absorbing the recovered carbon dioxide in the absorbing liquid 31 and circulating it in the fuel gas storage unit 11, and a circulation path 3 for collecting carbon dioxide. A separation path 4 for separation is provided.

The supply path 1 can be detachably connected to an external supply facility for storing fuel gas. A valve V1, a pressure sensor P1, a fuel gas storage unit 11, a valve V2, a pressure sensor P2, a valve V3, and a pressure adjusting valve 12 are arranged in order from the upstream in the supply path 1, and finally the fuel gas of the fuel utilization device 9 is arranged. It is connected to the introduction side of. Further, the branch path 1A branches at a position between the pressure sensor P2 and the valve V3 of the supply path 1, the valve V4 and the vacuum pump 13 are arranged from the upstream in the branch path 1A, and finally the valve V3 of the supply path 1 It joins the supply path 1 at a position between the pressure control valve 12 and the pressure control valve 12.

The pressure regulating valve 12 adjusts the pressure of the fuel gas supplied from the fuel gas storage unit 11 to the rated pressure for the rated operation of the fuel utilization device 9.

The vacuum pump 13 is a well-known pump such as a vane pump or a rotary pump, and is used when the pressure of the fuel gas supplied from the fuel gas storage unit 11 reaches a predetermined lower limit value (P2min1, see FIG. 6). Will be.

The recovery path 2 is connected to the exhaust gas discharge side of the fuel utilization device 9, the separation device 21, the second booster 22, and the valve V5 are arranged from the upstream, and finally the carbon dioxide introduction side of the gas-liquid mixing device 34. Connected to. Further, in the recovery path 2, the branch path 2A branches in the separation device 21, and the valve V6 is arranged in the branch path 2A, but the final end is open to the outside.

The separation device 21 is a device provided with a scavenger such as a lean absorbent solution or a solution of an alkali metal carbonate, and blows exhaust gas onto the scavenger to absorb carbon dioxide, and then heats the scavenger in the device. It has a structure to recover carbon dioxide. As the scavenger, hydrofluoroether (HFE) used as a refrigerant or the like (see, for example, US9267415B2) can also be applied.

Further, as another configuration for recovering carbon dioxide from the exhaust gas, the exhaust gas is supplied to an FT polymer for carbon dioxide separation (see, for example, Japanese Patent Application Laid-Open No. 2015-536814) to separate the carbon dioxide from the exhaust gas. Configurations can also be applied. The separation device 21 discharges carbon dioxide separated from the exhaust gas to the second booster 22.

The second booster 22 is a compressor that pressurizes the carbon dioxide discharged from the separation device 21 and supplies it to the carbon dioxide introduction side of the gas-liquid mixing device 34.

The opening degree of the valve V5 is controlled by a controller 8 (control unit) described later, and the flow rate of carbon dioxide introduced into the gas-liquid mixing device 34 is controlled.

The circulation path 3 circulates the absorbing liquid 31 capable of storing and releasing carbon dioxide, and in order from the circulation direction, the circulation pump 32, the temperature sensor T1, the temperature sensor T2, the pressure sensor P3, and the first gas-liquid separation device. 33, a pressure sensor P4, a valve V8, a gas-liquid mixing device 34, and a defoaming device 35 are arranged and returned to the circulation pump 32. Here, in the circulation path 3, the region between the temperature sensor T1 and the temperature sensor T2 is integrated with the communication passage 52 formed in the fuel gas storage portion 11. The communication passage 52 is in contact with the adsorbent 111 capable of storing and releasing fuel gas.

Further, the branch path 3A branches from the position between the pressure sensor P4 of the circulation path 3 and the valve V8. A valve V9 is arranged in the branch path 3A, but finally joins the circulation path 3 at a position between the defoaming device 35 and the circulation pump 32 of the circulation path 3.

The circulation pump 32 supplies the absorption liquid 31 flowing in from the defoaming device 35 or the valve V9 to the fuel gas storage unit 11 and circulates the absorption liquid 31 in the circulation path 3. The circulation pump 32 supplies the absorbing liquid 31 having a pressure of at least 5 Mpa or more to the fuel gas storage unit 11.

As the first gas-liquid separation device 33, various types such as a surface tension type and a centrifugal force type can be applied, and carbon dioxide absorbed in the absorbing liquid 31 is separated. When the valve V7, which will be described later, is closed, carbon dioxide is not separated from the absorbing liquid 31 in the first gas-liquid separating device 33.

The gas-liquid mixing device 34 is a known one such as an ejector 34a (see the second embodiment), a turbo mixer (trade name), an ultrafine bubble (registered trademark), etc., and mixes carbon dioxide with the absorbing liquid 31. be.

As the defoaming device 35, known devices such as an ultrasonic defoaming device, a shear defoaming device, and a centrifugal defoaming device can be applied, and carbon dioxide (or other components of exhaust gas) remaining in the absorption liquid 31 can be applied. Remove cavitation.

The separation path 4 is connected to the carbon dioxide discharge side of the first gas-liquid separation device 33, and the valve V7, the first booster 41, and the CO ₂ tank 42 are arranged from the upstream. By opening the valve V7, carbon dioxide is separated from the absorbing liquid 31 in the first gas-liquid separating device 33. Further, the first booster 41 boosts carbon dioxide and other carbon discharged from the first gas-liquid separation device 33 and supplies it to the CO ₂ tank 42. The first booster 41 and the CO ₂ tank 42 may be omitted to release carbon dioxide that has passed through the valve V7 to the outside.

The pressure sensor P1 detects the pressure in the fuel gas storage unit 11 when the fuel gas storage unit 11 is filled with the fuel gas.

The pressure sensor P2 detects the pressure of the fuel gas released from the fuel gas storage unit 11.

The pressure sensor P3 detects the pressure at a position between the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 and the introduction side of the absorption liquid 31 of the first gas-liquid separation device 33 in the circulation path 3. ..

The pressure sensor P4 detects the pressure at a position between the discharge side of the absorption liquid 31 of the first gas-liquid separation device 33 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34 in the circulation path 3.

The temperature sensor T1 detects the temperature of the absorbing liquid 31 immediately before being introduced into the fuel gas storage unit 11.

The temperature sensor T2 detects the temperature of the absorbing liquid 31 immediately after being discharged from the fuel gas storage unit 11.

The controller 8 (control unit) is, for example, a computer composed of a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). The controller 8 constitutes the fuel gas adsorption storage system 100 of the present embodiment, and is a component including a program for executing the system. Further, the controller 8 can turn on / off the fuel utilization device 9 and control its output, and can also operate by a command from an ECU or the like that controls the entire vehicle.

[Control flow when releasing fuel gas]
FIG. 6 is a flow chart when the fuel gas is discharged from the fuel gas storage unit 11 and the absorption liquid 31 absorbs carbon dioxide in the fuel gas adsorption storage system 100 of the first embodiment. In the initial state, the valves V1 to V9 are closed.

In step S101, the controller 8 opens the valve V2 and the valve V3. As a result, the fuel gas is supplied from the fuel gas storage unit 11 to the fuel utilization device 9. Further, at this time, the fuel gas begins to separate from the adsorbent 111, and released heat (endothermic) is generated.

In step S102, the controller 8 (or ECU) activates the fuel utilization device 9. As a result, the fuel gas is consumed in the fuel utilization device 9, and the exhaust gas is supplied to the separation device 21. The exhaust gas contains at least carbon dioxide and also contains gases such as NOx, _H2O , and _O2 .

In step S103, the controller 8 activates the second booster 22 and opens the valve V5 at a predetermined opening degree to open the valve V6. As a result, the exhaust gas is separated into residual gas in addition to carbon dioxide and carbon dioxide in the separation device 21, carbon dioxide is supplied to the second booster 22, and the residual gas is discharged to the outside through the valve V6. Further, the second booster 22 boosts carbon dioxide and supplies it to the gas-liquid mixing device 34.

In step S104, the controller 8 opens the valve V8 and starts the circulation pump 32. As a result, the absorbing liquid 31 circulates and absorbs carbon dioxide in the gas-liquid mixing device 34 to generate heat of adsorption (heat generation). Further, the absorbing liquid 31 exchanges heat with the adsorbent 111 in the fuel gas storage unit 11 and supplies the adsorbent 111 with the amount of heat that cancels the heat released by the adsorbent 111.

In step S105, the controller 8 determines whether or not the fuel utilization device 9 has stopped, and if YES, the process proceeds to step S106, and if NO, the process proceeds to step S113.

In step S106, the controller 8 determines whether the temperature difference obtained by subtracting the temperature detected by the temperature sensor T2 from the temperature detected by the temperature sensor T1 is a predetermined temperature difference ΔT1 (for example, 10 [° C.]) or more, and YES. If there is, the process proceeds to step S107, and if NO, the process proceeds to step S108.

When the fuel gas is discharged from the fuel gas storage unit 11, the absorption liquid 31 undergoes heat exchange as it flows through the circulation path 3 (communication passage 52) in the fuel gas storage unit 11, and its temperature drops. Therefore, the temperature detected by the temperature sensor T2 is lower than the temperature detected by the temperature sensor T1.

In step S107, the controller 8 increases the output of the circulation pump 32 by a predetermined amount and / or increases the opening degree of the valve V5 by a predetermined amount. By increasing the output of the circulation pump 32, heat exchange between the absorbing liquid 31 and the adsorbent 111 can be promoted, and uneven release of fuel gas in the adsorbent 111 can be reduced. Further, by increasing the opening degree of the valve V5, the amount of carbon dioxide absorbed by the absorbing liquid 31 is increased, the heat of adsorption generated by the absorbing liquid 31 is increased, and the amount of fuel gas released in the entire adsorbent 111 is increased. Can be increased. Even if the controller 8 controls to fully open the opening degree of the valve V5 from the beginning in step S103 and to increase the output of the second booster 22 in conjunction with the increase of the output of the circulation pump 32 in step S107. good.

In step S108, the controller 8 determines whether or not the pressure detected by the pressure sensor P3 has reached a predetermined upper limit value (P3max, for example, 8 [Mpa]), and if YES, the process proceeds to step S109, and NO. If so, the process proceeds to step S110. The upper limit value (P3max) is set, for example, as the upper limit withstand voltage of the circulation path 3.

In step S109, the controller 8 opens the valve V7 and activates the first booster 41. As a result, carbon dioxide is separated from the absorption liquid 31 introduced into the first gas-liquid separation device 33, and the carbon dioxide is boosted to a predetermined pressure by the second booster 22 and supplied to the CO ₂ tank 42.

Further, the controller 8 increases the output of the circulation pump 32 when the pressure detected by the pressure sensor P4 becomes a predetermined lower limit value (P4min) or less. As a result, the gas-liquid mixing device 34 can secure the pressure of the absorbing liquid 31 required for mixing carbon dioxide.

In step S110, the controller 8 determines whether or not the pressure detected by the pressure sensor P2 is equal to or less than the first lower limit value (P2min1, for example, 0.3 [Mpa]), and if YES, proceeds to step S111. If NO, the process proceeds to step S105.

In step S111, the controller 8 closes the valve V3, opens the valve V4, and starts the vacuum pump 13. As a result, the fuel gas is continuously supplied to the pressure regulating valve 12 at a pressure equal to or higher than the first lower limit value (P2min1).

In step S112, the controller 8 determines whether or not the pressure detected by the pressure sensor P2 is the second lower limit value (P2min2). If YES, the process proceeds to step S114, and if NO, the process proceeds to step S105. .. The second lower limit value (P2min2) is the pressure detected by the pressure sensor P2 when the pressure on the fuel gas discharge side of the pressure regulating valve 12 becomes lower than the rated pressure (for example, 0.3 [Mpa]) of the fuel utilization device 9. It is a value and is set to, for example, 0.1 [Mpa].

In step S113, the controller 8 stops the second booster 22 and the first booster 41 when the fuel utilization device 9 is stopped, and stops the system by closing all the valves. Here, the case where the fuel utilization device 9 is stopped is a case where the fuel utilization device 9 functions as a generator, for example, when the SOC of the battery for driving the motor reaches a predetermined upper limit value. Further, when the fuel utilization device 9 is an engine and the driving force thereof is transmitted to the drive wheels, for example, when the vehicle is temporarily stopped (idling stop) or when the vehicle (system) is completely stopped.

In step S114, the controller 8 determines that the fuel gas stored in the fuel gas storage unit 11 is insufficient, and outputs a warning signal that can be identified by the driver.

[Energy balance at the time of fuel gas release]
FIG. 7 is an energy balance in the case of supplying the released heat generated when the fuel gas is discharged from the fuel gas storage unit 11 from the outside, and the fuel gas storage unit from the absorption liquid 31 with the recovery rate of carbon dioxide as a parameter. A graph showing the relationship between the amount of heat that can be supplied to 11 and the vehicle speed, and auxiliary equipment (second booster 22, circulation pump 32) constituting the heat of adsorption of carbon dioxide and the adsorption and storage system 100 of fuel gas of the first embodiment. ) Is a circle graph showing the ratio with the power consumption.

Here, too, the description will be made on the premise that the heat of adsorption of carbon dioxide in the absorbing liquid 31 is equal to the heat of adsorption of the adsorbent 111. As described above, when the recovery rate of carbon dioxide is approximately = 83.3 [%] or more, the heat of adsorption / heat of release of methane can be covered by the heat of release / heat of carbon dioxide. Therefore, from the viewpoint of heat balance, if the recovery rate of carbon dioxide is equal to or higher than the above value, the amount of heat to be supplied to the fuel gas storage unit 11 when the fuel gas is discharged from the fuel gas storage unit 11 is passed through the circulation path. It can be covered by the heat of adsorption of carbon dioxide supplied to 3.

However, from the viewpoint of the energy balance including power consumption, when the absorbing liquid 31 that has absorbed carbon dioxide is circulated in the circulation path 3, the boosting of carbon dioxide by the second booster 22 (consumption of the second booster 22). It is necessary to consider excluding (electricity) and the output (power consumption) of the circulation pump 32.

Further, the vehicle is running during the release of the fuel gas, but as the vehicle speed increases, the flow rate of the fuel gas, that is, the heat released when the fuel gas is released from the adsorbent 111 increases. Correspondingly, the power consumption of the second booster 22 and the circulation pump 32 increases, and the heat of adsorption when carbon dioxide is adsorbed on the absorbing liquid 31 increases.

Further, as the vehicle speed increases, the amount of heat to be supplied to the fuel gas storage unit 11 (heat released) increases, and the heat of adsorption to be generated in the circulation path 3 also increases, but the efficiency of carbon dioxide adsorption to the absorbing liquid 31 increases. The amount of heat to be cooled by the absorbent 31 is also increased in order to suppress the decrease in the amount of carbon dioxide. Therefore, it is necessary to balance the heat of both (the temperature of the fuel gas storage unit 11 and the temperature of the absorbing liquid 31 are close to each other), and it is necessary to increase the output (power consumption) of the second booster 22 and the circulation pump 32. be.

From the above, the energy balance when the fuel gas is released from the fuel gas storage unit 11 and the carbon dioxide is absorbed by the absorbing liquid 31 is calculated as follows. The power consumption shown in FIG. 7 is the sum of the power consumption of the second booster 22 and the circulation pump 32.

As shown in FIG. 7, the line showing the energy balance is. As the vehicle speed increases, it increases in the negative direction. The line of α = 0 shows the energy balance when the heat of adsorption of carbon dioxide is not used at all, and is, for example, −567 [W] at a position where the vehicle speed is 180 km / h. However, in this case, it is synonymous with not using the circulation pump 32, and the power consumption of the second booster 22 and the circulation pump 32 can be set to zero. Further, in this case, when all the heat to be supplied to the fuel gas storage unit 11 is covered by, for example, a heater (not shown) attached to the fuel gas storage unit 11, the heater (not shown) consumes 567 [W]. Become.

For example, the energy balance at a carbon dioxide recovery rate α = 0.5 and a speed of 180 km / h is -391 [W]. As a result, the net amount of heat that can be supplied to the fuel gas storage unit 11 is calculated to be −391- (−567) = 176 [W]. On the other hand, the power consumption of the circulation pump 32 is calculated to be 164 [W]. Therefore, as shown in the pie chart (center) of FIG. 7, the net amount of heat (Heat) supplied to the fuel gas storage portion 11 exceeds the power consumption (Power) of the second booster 22 and the circulation pump 32. ing.

Further, in this case, of the amount of heat to be supplied to the fuel gas storage unit 11, the amount covered by the heater (not shown) is 391 [W], which is larger than that covered by the heater (not shown) ((567). -391) / 567) × 100 = 31 [%] can be reduced.

For example, the recovery rate of carbon dioxide is α = 0.9, and the energy balance at a speed of 180 km / h is −250 [W]. As a result, the net amount of heat that can be supplied to the fuel gas storage unit 11 is calculated as −250 − (−567) = 317 [W]. On the other hand, the power consumption is calculated as 295 [W]. Therefore, as shown in the pie chart (right) of FIG. 7, the net amount of heat (Heat) supplied to the fuel gas storage unit 11 exceeds the power consumption (Power) of the circulation pump 32.

Further, in this case, of the amount of heat to be supplied to the fuel gas storage unit 11, the amount covered by the heater (not shown) is 391 [W], which is more than the case where the heater (not shown) covers all of the heat (not shown). (567-250) / 567) × 100 = 56 [%] can be reduced.

For example, the energy balance at a carbon dioxide recovery rate α = 0 and a speed of 20 km / h is −63 [W]. Further, the recovery rate of carbon dioxide is α = 0.5, and the energy balance at a speed of 20 km / h is −43 [W]. As a result, the net amount of heat that can be supplied to the fuel gas storage unit 11 is calculated as 433 (−63) = 20 [W]. On the other hand, the power consumption of the second booster 22 and the circulation pump 32 is calculated to be 18 [W]. Therefore, as shown in the pie chart (left) of FIG. 7, the net amount of heat (Heat) supplied to the fuel gas storage unit 11 exceeds the power consumption (Power) of the second booster 22 and the circulation pump 32. ing.

Further, in this case, of the amount of heat to be supplied to the fuel gas storage unit 11, the amount covered by the heater (not shown) is 43 [W], and all of the heat is covered by the heater (not shown) (63 [). W]) can be reduced by ((63-43) / 63) × 100 = 32 [%]. Therefore, in any case, it can be seen that the energy balance is improved and the energy consumption can be reduced as compared with the case where the fuel gas storage unit 11 (adsorbent 111) is directly heated by a heater or the like.

[Control flow when filling fuel gas]
FIG. 8 is a flow chart when the fuel gas is filled in the fuel gas storage unit 11 and carbon dioxide is released from the absorption liquid 31 in the fuel gas adsorption storage system 100 of the first embodiment. In the initial state, the valves V1 to V9 are closed. Further, the supply path 1 is connected to an external supply facility.

In step S201, the controller 8 opens the valve V1. As a result, the fuel gas is supplied to the fuel gas storage unit 11, and the fuel gas is adsorbed by the adsorbent 111 to generate heat of adsorption.

In step S202, the controller 8 opens the valve V9 (or the valve V8), opens the valve V7 at a predetermined opening degree, and starts the circulation pump 32 and the first booster 41. As a result, the absorbing liquid 31 circulates in the circulation path 3, and carbon dioxide is separated from the absorbing liquid 31 in the first gas-liquid separating device 33, and at that time, heat released (endothermic) is generated. Therefore, the absorbing liquid 31 can take out the heat of adsorption generated by the adsorbent 111.

Further, the carbon dioxide separated from the absorption liquid 31 is boosted by the first booster 41 and supplied to the CO ₂ tank 42.

In the state where the valve V9 is opened and the valve V8 is closed, the circulation path 3 is a path that bypasses the gas-liquid mixing device 34 and the defoaming device 35 and circulates. In this case, it is possible to avoid the pressure loss of the absorbing liquid 31 generated by the gas-liquid mixing device 34 and the defoaming device 35, thereby reducing the load on the circulation pump 32. Of course, the valve V8, the branch path 3A, and the valve V9 may be omitted so that the circulation path 3 includes the gas-liquid mixing device 34 and the defoaming device 35 even when carbon dioxide is released.

In step S203, the controller 8 determines whether or not the pressure of the pressure sensor P1 has reached a predetermined upper limit value (P1max, for example, 3.5 [Mpa]), and if YES, the process proceeds to step S206, and NO. If so, the process proceeds to step S204.

In step S204, the controller 8 determines whether the temperature difference obtained by subtracting the temperature detected by the temperature sensor T1 from the temperature detected by the temperature sensor T2 is a predetermined temperature difference ΔT2 (for example, 10 [° C.]) or more, and YES. If there is, the process proceeds to step S205, and if NO, the process proceeds to step S203.

When the fuel gas storage unit 11 is filled with fuel gas, heat exchange progresses and the temperature of the absorption liquid 31 rises as it flows through the circulation path 3 (communication passage 52) in the fuel gas storage unit 11. Therefore, the temperature detected by the temperature sensor T1 is lower than the temperature detected by the temperature sensor T2.

In step S205, the controller 8 increases the output of the circulation pump 32 and / or increases the opening degree of the valve V7. By increasing the output of the circulation pump 32, heat exchange between the absorbing liquid 31 and the adsorbent 111 can be promoted, and uneven adsorption of fuel gas in the adsorbent 111 can be reduced. Further, by increasing the opening degree of the valve V7, the amount of carbon dioxide released from the absorption liquid 31 is increased, the heat released by the absorption liquid 31 is increased, and the amount of fuel gas adsorbed by the entire adsorbent 111 is increased. Can be increased.

In step S206, the controller 8 determines that the fuel gas storage unit 11 is sufficiently filled with fuel gas, stops the circulation pump 32 and the first booster 41, and closes all the valves to stop the system.

The carbon dioxide stored in the CO ₂ tank 42 can be supplied to an external supply facility, for example, and the carbon dioxide is used for industrial purposes such as oil extraction in an oil field.

[Relationship between rapid filling of fuel gas and carbon dioxide recovery rate]
FIG. 9 shows a case where the amount of heat to be taken out from the fuel gas storage unit 11 when the fuel gas is filled in the fuel gas storage unit 11 is covered by the heat released from carbon dioxide when the recovery rate of carbon dioxide is used as a parameter. It is a graph which shows the relationship between the filling amount of a fuel gas, the filling time of a fuel gas, and the temperature of a fuel gas storage part 11.

In FIG. 9, it is assumed that the fuel gas storage unit 11 is rapidly filled with fuel gas in a short time (for example, 10 minutes), and the upper limit temperature (for example, 40) at which the fuel gas can be rapidly adsorbed on the adsorbent 111 within that time is assumed. [℃]) The recovery rate of carbon dioxide was examined so as not to exceed it. The recovery rate represents the recovery rate of carbon dioxide from the fuel utilization device 9 as described above, but the flow rate of the fuel gas filled in the fuel gas storage unit 11 and the flow rate of the carbon dioxide released from the absorption liquid 31 Synonymous with molar ratio. Further, when calculating the temperature of the fuel gas storage unit 11, the amount of heat radiated from the fuel gas storage unit 11 to the outside is taken into consideration. Further, it is assumed that the heat of adsorption / release of carbon dioxide in the absorption liquid 31 is equal to the heat of adsorption / heat of release of the adsorbent 111, and the volume of the absorption liquid 31 is equal to the volume of the adsorbent 111.

Recovery rate α = 0, that is, when the fuel gas storage unit 11 is filled with fuel gas and no heat exchange is performed with the absorbing liquid 31, the filling rate is about 10 minutes after the start of filling. It can be seen that when the temperature reaches [%], the temperature of the fuel gas storage unit 11 reaches the upper limit temperature (for example, 40 [° C.]), and further rapid filling becomes difficult.

When the recovery rate α = 0.75, the temperature of the fuel gas storage unit 11 reaches the upper limit temperature (for example, 40 [° C.]) when about 50 [%] filling is completed about 5 minutes after the start of filling. It turns out that further rapid filling becomes difficult.

When the recovery rate α = 0.80, the temperature of the fuel gas storage unit 11 reaches the upper limit temperature (for example, 40 [° C.]) at the stage where about 90 [%] filling is completed about 9 minutes after the start of filling. It turns out that further rapid filling becomes difficult.

When the recovery rate α = 0.90, the temperature of the fuel gas storage unit 11 gradually decreases monotonically immediately after the start of filling. Then, about 10 minutes after the start of filling, the temperature of the fuel gas storage unit 11 does not exceed the upper limit temperature (for example, 40 [° C.]) even when the filling of about 100 [%] is completed. Therefore, it can be seen that rapid filling is sufficiently possible if the recovery rate α = 0.90.

As described above, when the recovery rate of carbon dioxide is 83.3 [%] or more, the curve shown in FIG. 7 does not monotonically increase with the filling time, and it is considered that rapid filling is possible.

By the way, as shown in FIG. 2, when the pressure of carbon dioxide in contact with the absorption liquid 31 is 5 [Mpa], the heat of adsorption / heat of release of carbon dioxide of the absorption liquid 31 is about 280 [kJ / L]. The heat of adsorption / heat of release of the adsorbent 111 is about 170 [kJ / L]. Therefore, when the volume of the absorbent liquid 31 and the volume of the adsorbent 111 are the same, if the recovery rate of carbon dioxide is 83.3 (170/280) = 50.6 [%] or more, the above-mentioned rapid filling is possible. Become.

Further, when the recovery rate of carbon dioxide is 83.3 [%] or more, it is possible to reduce at least the volume of the absorbing liquid 31 by ((280-170) / 280) × 100 = 39 [%], for example. If the volume of the fuel gas storage unit 11 (volume of the adsorbent 111) is 50 [L], the volume of the absorbing liquid 31 can be set to about 30 [L].

[Effect of the first embodiment]
According to the fuel gas adsorption storage system 100 of the first embodiment, the fuel gas storage unit 11 filled with the adsorbent 111 capable of storing and releasing the fuel gas and the fuel gas storage unit 11 are circulated and carbon dioxide is emitted. The fuel gas storage unit 11 and the absorption liquid 31 are thermally connected to each other, including the absorption liquid 31 that can be stored and released.

With the above configuration, when the fuel gas is adsorbed on the adsorbent 111, heat of adsorption (heat generation) is generated, which reduces the adsorption capacity of the fuel gas. Further, when the fuel gas is released from the adsorbent 111, heat release (endothermic) is generated, which reduces the release capacity of the fuel gas. On the other hand, when carbon dioxide is adsorbed on the absorption liquid 31, heat of adsorption (heat generation) is generated, and when carbon dioxide is released from the absorption liquid 31, heat of release (heat absorption) is generated. Therefore, by releasing carbon dioxide when filling the fuel gas and absorbing carbon dioxide when releasing the fuel gas, the heat of adsorption generated in the fuel gas storage unit 11 and the heat of release generated in the absorbing liquid 31 are combined. It is possible to exchange heat between the above and the heat released from the fuel gas storage unit 11 and the heat of adsorption generated by the absorbing liquid 31. Therefore, it is possible to suppress a decrease in the adsorption capacity when the fuel gas is adsorbed on the adsorbent 111 and a decrease in the release capacity when the fuel gas is released from the adsorbent 111. Further, since the absorbent liquid 31 and the adsorbent 111 can exchange heat without using other refrigerants, the efficiency of heat exchange can be improved, and the equipment for storing the other refrigerants and carbon dioxide (CO ₂ ). The storage unit 11a) is also unnecessary. From the above, it is possible to realize simple heat exchange and avoid weighting the system.

In the present embodiment, a circulation path 3 in which a communication passage 52 inside the fuel gas storage portion 11 is incorporated and filled with an absorption liquid 31 and a circulation pump 32 for circulating the absorption liquid 31 in the circulation path 3 are included. As a result, heat exchange between the fuel gas storage unit 11 (adsorbent 111) and the absorbing liquid 31 can be efficiently performed with a simple configuration.

In the present embodiment, a gas-liquid mixing device 34 for absorbing carbon dioxide is arranged in the circulation path 3. As a result, carbon dioxide can be taken into the circulation path 3 with a simple configuration.

In the present embodiment, the circulation pump 32 is arranged between the discharge side of the absorption liquid 31 of the gas-liquid mixing device 34 of the circulation path 3 and the introduction side of the absorption liquid 31 of the fuel gas storage unit 11, and the air of the circulation path 3 is provided. A defoaming device 35 for preventing cavitation is arranged at a position between the discharge side of the absorption liquid 31 of the liquid mixing device 34 and the introduction side of the absorption liquid 31 of the circulation pump 32. As a result, the efficiency of absorbing carbon dioxide into the absorbing liquid 31 can be increased.

In the present embodiment, in the fuel gas adsorption storage system 100 connected to the fuel utilization device 9 that consumes the fuel gas and emits the exhaust gas including carbon dioxide, the fuel gas introduction side and the fuel of the fuel utilization device 9 Carbon dioxide is discharged from the fuel supply valves (valves V2, valves V3) arranged in the path (supply path 1) communicating with the fuel gas discharge side of the gas storage unit 11 and the exhaust gas discharged from the fuel utilization device 9. A carbon dioxide introduction valve (valve V5) arranged in a path (recovery path 2) connecting the separation device 21 for extraction, the carbon dioxide discharge side of the separation device 21, and the carbon dioxide introduction side of the gas-liquid mixing device 34. The first temperature sensor (temperature sensor T1) for measuring the temperature between the discharge side of the absorption liquid 31 of the circulation pump 32 of the circulation path 3 and the introduction side of the absorption liquid 31 of the fuel gas storage unit 11, and the circulation path. A second temperature sensor (temperature sensor T2) for measuring the temperature between the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34, and a first temperature sensor. The temperature information of the (temperature sensor T1) and the second temperature sensor (temperature sensor T2) are input, and the circulation pump 32, the fuel supply valve (valve V2, valve V3), and the carbon dioxide introduction valve (valve V5) are operated. A control unit (controller 8) for controlling is provided, and the control unit (controller 8) opens the fuel supply valve (valve V2, valve V3) and the carbon dioxide introduction valve (valve V5), and the first temperature sensor (controller 8). The output of the circulation pump 32 is controlled so that the temperature difference between the temperature detected by the temperature sensor T1) and the temperature detected by the second temperature sensor (temperature sensor T2) is equal to or less than the predetermined temperature difference (ΔT1). Alternatively, the opening degree of the carbon dioxide introduction valve (valve V5) is controlled. As a result, when the fuel gas is discharged from the fuel gas storage unit 11, the fuel gas can be efficiently and evenly discharged from the adsorbent 111.

In the present embodiment, the first gas-liquid separation device 33 is arranged at a position between the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 of the circulation path 3 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34. The exhaust valve (valve V7) arranged on the carbon dioxide discharge side of the first gas-liquid separation device 33, the discharge side of the absorption liquid 31 of the fuel gas storage portion 11 of the circulation path 3, and the first gas-liquid separation device. A pressure sensor (pressure sensor P3) arranged at a position between the introduction side of the absorption liquid 31 of 33 is provided, and the control unit (controller 8) determines the pressure detected by the pressure sensor (pressure sensor P3). When the pressure (P3max) is exceeded, the exhaust valve (V7) is opened. As a result, the pressure resistance of the circulation path 3 can be protected.

In the present embodiment, a fuel filling valve (valve V1) arranged in a path (supply path 1) connecting the fuel gas introduction side of the fuel gas storage unit 11 and the external supply facility (not shown) in which the fuel gas is stored. ), The first gas-liquid separation device 33 arranged between the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 of the circulation path 3 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34, and the first. The exhaust valve (valve V7) arranged on the carbon dioxide discharge side of the gas-liquid separation device 33, the discharge side of the absorption liquid 31 of the circulation pump 32 of the circulation path 3, and the introduction side of the absorption liquid 31 of the fuel gas storage unit 11. The first temperature sensor (temperature sensor T1) that measures the temperature between the valve, the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 of the circulation path 3, and the introduction side of the absorption liquid 31 of the first gas-liquid separation device 33. The temperature information of the second temperature sensor (temperature sensor T2) that measures the temperature between the gas and the first temperature sensor (temperature sensor T1) and the second temperature sensor (temperature sensor T2) is input and circulated. A control unit (controller 8) for controlling a pump 32, a fuel filling valve (valve V1), and an exhaust valve (valve V7) is provided, and the control unit (controller 8) includes a fuel filling valve (valve V1) and an exhaust valve (valve V1). The valve V7) is opened, and the temperature difference between the temperature detected by the first temperature sensor (temperature sensor T1) and the temperature detected by the second temperature sensor (temperature sensor T2) is equal to or less than the predetermined temperature difference (ΔT2). Therefore, the output of the circulation pump 32 is controlled, or the opening degree of the exhaust valve (valve V7) is controlled. As a result, when the fuel gas storage unit 11 is filled with the fuel gas, the fuel gas can be efficiently and evenly adsorbed on the adsorbent 111.

In the present embodiment, a carbon dioxide storage tank (CO ₂ tank 42) connected to the carbon dioxide emission side of the exhaust valve (valve V7) and capable of storing carbon dioxide, an exhaust valve (valve V7), and a carbon dioxide storage tank ( It is provided with a first booster 41 interposed between the CO ₂ tank 42) to boost the carbon dioxide discharged from the exhaust valve (valve V7) and supply it to the carbon dioxide storage tank (CO ₂ tank 42). As a result, carbon dioxide can be retained without being discharged to the outside.

In the present embodiment, the absorbing liquid 31 can selectively absorb carbon dioxide because the heat of adsorption of carbon dioxide is higher than the heat of adsorption of other gases. This makes it possible to efficiently absorb carbon dioxide.

[Second Embodiment]
FIG. 10 is a block diagram showing a main configuration of the fuel gas adsorption storage system 100 of the second embodiment. In the following embodiments, the components common to the first embodiment are assigned the same numbers, and the description thereof will be omitted unless necessary.

The adsorption storage system 100 of the second embodiment is substantially the same as that of the first embodiment, but the gas-liquid mixing device 34 is an ejector 34a. The ejector 34a injects the absorbing liquid 31 at high speed in the housing by a nozzle, sucks carbon dioxide by creating a low pressure space in the housing, and mixes the carbon dioxide with the absorbing liquid 31.

The circulation pump 32 is arranged at a position between the first gas-liquid separation device 33 and the valve V8 (valve V9) in the circulation path 3. In the second embodiment (and the third embodiment described later), the control of filling the fuel gas storage unit 11 with the fuel gas and the control of discharging the fuel gas from the fuel gas storage unit 11 are the same as those of the first embodiment. The same is true.

In the second embodiment, since the circulation pump 32 can supply the absorbent liquid 31 with a large pressure to the ejector 34a, the injection speed of the absorbent liquid 31 in the ejector 34a can be increased, whereby the low pressure space in the ejector 34a can be easily created. It can be formed to increase the absorption efficiency of carbon dioxide in the ejector 34a.

[Third Embodiment]
FIG. 11 is a block diagram showing a main configuration of the fuel gas adsorption storage system 100 of the third embodiment. In the third embodiment, the absorption liquid 31 has a higher heat of adsorption / release of carbon dioxide than other gases, such as an amine compound, and therefore can selectively absorb carbon dioxide than other gases. What is applied is applied. Therefore, when the absorption liquid 31 is brought into contact with the absorption liquid 31 with carbon dioxide, NOx, or the like, carbon dioxide is efficiently absorbed by the absorption liquid 31, but the absorption efficiency of other gases is low and the absorption liquid is low. It is easy to leave 31.

Therefore, in the third embodiment, the dehumidifier 21a is arranged instead of the separation device 21, and the dehumidifier 21a supplies the exhaust gas from which the water (H ₂ O) has been removed to the second booster 22.

Further, a second gas-liquid separation device 36 is arranged between the defoaming device 35 of the circulation path 3 and the circulation pump 32. The second gas-liquid separation device 36 may have the same structure as the first gas-liquid separation device 33, but one set to an efficiency that does not allow carbon dioxide to separate from the absorption liquid 31 is applied.

As a result, NOx, O ₂ and the like are added to the absorption liquid 31 between the discharge side of the absorption liquid 31 of the gas-liquid mixing device 34 and the introduction side of the absorption liquid 31 of the second gas-liquid separation device 36 in the circulation path 3. Although gas is mixed, almost only carbon dioxide is absorbed in the absorption liquid 31 in the other portion.

According to the third embodiment, it is connected to a fuel utilization device 9 that consumes fuel gas and discharges exhaust gas containing carbon dioxide, and the heat of adsorption of carbon dioxide in the absorption liquid 31 is higher than the heat of adsorption of other gas. In the fuel gas adsorption and storage system 100 that can selectively absorb carbon dioxide at a high rate, a route (recovery route) that connects the exhaust gas discharge side of the fuel utilization device 9 and the exhaust gas introduction side of the gas-liquid mixing device 34. At a position between the dehumidifier 21a arranged in 2) and removing water from the exhaust gas and the discharge side of the absorption liquid 31 of the defoaming device 35 and the introduction side of the absorption liquid 31 of the circulation pump 32 in the circulation path 3. It is provided with a second gas-liquid separation device 36 that is arranged and removes components of exhaust gas mixed in the absorption liquid 31 other than carbon dioxide. As a result, the exhaust gas exhausted from the fuel utilization device 9 can be introduced into the gas-liquid mixing device 34 without using the separating device 21, so that it is possible to avoid an increase in the size of the system.

[Fourth Embodiment]
FIG. 12 is a block diagram showing a main configuration of the fuel gas adsorption storage system 100 of the fourth embodiment. The adsorption storage system 100 of the fourth embodiment is configured in the case where the circulation of the absorption liquid 31 in the circulation path 3 is carried out at a lower pressure than that of the first embodiment or the like. By setting the entire circulation path 3 to a low pressure in this way, the required strength of the piping and the fuel gas storage portion 11 (communication passage 52) forming the circulation path 3 can be reduced, and the circulation path 3 can be reduced by that amount. In addition, the weight and size of the communication passage 52 can be reduced. In FIG. 12, the branch path 3A, the valve V8, and the valve V9 are not shown.

In the fourth embodiment, the first pressure regulating valve 37 is arranged at a position between the discharge side of the absorption liquid 31 of the fuel gas storage unit 11 of the circulation path 3 and the introduction side of the absorption liquid 31 of the first gas-liquid separation device 33. The second pressure regulating valve 38 is arranged at a position between the discharge side of the absorption liquid 31 of the first gas-liquid separation device 33 of the circulation path 3 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34.

Here, the circulation pump 32 is set so that the pressure of the absorbing liquid 31 when supplying the absorbing liquid 31 to the fuel gas storage unit 11 is 1-5 [Mpa]. As a result, the power consumption of the circulation pump 32 can be reduced.

In the fourth embodiment, as in the first embodiment, the valves V2 and V3 are opened to release the fuel gas from the fuel gas storage unit 11, and carbon dioxide is introduced into the gas-liquid mixing device 34. However, the valve V7 The first booster 41 is started from the beginning, and the first gas-liquid separation device 33 controls to separate most of the carbon dioxide.

The first pressure regulating valve 37 reduces the pressure of the absorbing liquid 31 discharged from the fuel gas storage unit 11 to, for example, 0.3-0.5 [Mpa] and supplies it to the first gas-liquid separating device 33. Further, the first pressure regulating valve 37 closes the circulation path 3 when the pressure of the absorbing liquid 31 on the first gas-liquid separating device 33 side becomes higher than the pressure of the absorbing liquid 31 on the fuel gas storage portion 11. It has a check valve structure. By depressurizing the absorbing liquid 31 with the first pressure regulating valve 37, carbon dioxide can be efficiently separated from the absorbing liquid 31.

The second pressure regulating valve 38 reduces the pressure of the absorbing liquid 31 discharged from the first gas-liquid separating device 33 to, for example, 0.15-0.20 [Mpa] and supplies it to the gas-liquid mixing device 34. Further, the second pressure regulating valve 38 closes the circulation path 3 when the pressure of the absorbing liquid 31 on the gas-liquid mixing device 34 side becomes higher than the pressure of the absorbing liquid 31 on the first gas-liquid separating device 33 side. It has a check valve structure.

By further reducing the pressure of the absorbing liquid 31 with the second pressure regulating valve 38, the pressure of the absorbing liquid 31 in the gas-liquid mixing device 34 is reduced to 0.15-0.20 [Mpa]. Therefore, the pressure of carbon dioxide supplied to the gas-liquid mixing device 34 can also be reduced, and the power consumption of the second booster 22 can be reduced accordingly.

According to the fourth embodiment, in the fuel gas adsorption storage system 100 connected to the fuel utilization device 9 that consumes the fuel gas and emits the exhaust gas containing carbon dioxide, the exhaust discharged from the fuel utilization device 9 The separation device 21 that extracts carbon dioxide from the gas, the second booster 22 that pressurizes the carbon dioxide supplied from the separation device 21 and supplies it to the gas-liquid mixing device 34, and the fuel gas storage unit 11 of the circulation path 3. Discharge of the first gas-liquid separation device 33 arranged between the discharge side of the absorption liquid 31 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34, and the absorption liquid 31 of the fuel gas storage unit 11 of the circulation path 3. A first gas-liquid separating device 33, which is arranged between the side and the introduction side of the absorbing liquid 31 of the first gas-liquid separating device 33, decompresses the absorbing liquid 31 discharged from the fuel gas storage unit 11 and supplies the absorbing liquid 31 to the first gas-liquid separating device 33. A pressure regulating valve 37 is provided. As a result, carbon dioxide can be efficiently separated from the absorption liquid 31 by depressurizing the absorption liquid 31 with the first pressure regulating valve 37.

According to the fourth embodiment, the first gas-liquid separation is arranged between the discharge side of the absorption liquid 31 of the first gas-liquid separation device 33 of the circulation path 3 and the introduction side of the absorption liquid 31 of the gas-liquid mixing device 34. A second pressure regulating valve 38 for reducing the pressure of the absorbing liquid 31 discharged from the device 33 and supplying it to the gas-liquid mixing device 34 is provided. As a result, the pressure of the carbon dioxide supplied to the gas-liquid mixing device 34 can be reduced by further reducing the pressure of the absorbing liquid 31 by the second pressure regulating valve 38, and the power consumption of the second booster 22 can be reduced accordingly. Can be reduced.

[Fuel gas storage 11 and circulation path 3]
FIG. 13 is a cross-sectional view (longitudinal direction) of the fuel gas storage unit 11. FIG. 14 is a cross-sectional view (horizontal direction) of the fuel gas storage unit 11. FIG. 15 is a schematic diagram showing a circulation path 3 (communication passage 52) of the absorption liquid 31 in the fuel gas storage unit 11. The structure around the fuel gas storage unit 11 is the same as that of the first embodiment and the like, but only a part thereof is shown in the figure.

As shown in FIG. 13, the fuel gas storage unit 11 is divided into a plurality of (10) tubular branch chambers. Then, by filling each branch chamber with the adsorbent 111, a plurality of (10 pieces, only 5 pieces are shown in FIG. 14) divided storage portions 5A-5J are formed.

In the divided storage unit 5A-5J, a gas flow path 51 through which fuel gas flows is formed in the central portion along the longitudinal direction (horizontal direction) of the tube. As the fuel gas flows through the gas flow path 51, the fuel gas diffuses from the gas flow path 51 to the adsorbent 111 and is adsorbed on the adsorbent 111. Further, the fuel gas released from the adsorbent 111 is guided to the gas flow path 51 and discharged to the outside of the fuel gas storage unit 11.

By connecting the gas flow path 51 in series with another adjacent gas flow path 51, for example, as shown in FIG. 14, the divided storage portions 5A-5J can be connected in series with respect to the gas flow path 51. .. It is also possible to connect a part or all of the gas flow path 51 in parallel.

Further, the fuel gas storage unit 11 is also formed with a communication passage 52 through which the absorbing liquid 31 which is a refrigerant flows. The communication passage 52 constitutes a part of the circulation path 3 (see FIG. 5 and the like). Further, by connecting the communication passage 52 in series with another adjacent communication passage 52, similarly to the gas flow path 51, the divided storage portions 5A-5J can be connected in series with respect to the communication passage 52. By appropriately designing the thickness of the wall forming the branch chamber, a large number of the communication passages 52 can be arranged inside the wall, and are arranged adjacent to each other so that heat can be exchanged with the divided storage portions 5A-5J. Will be done. As described above, even if the continuous passage 52 is adjacent to the divided storage unit 5A-5J, in the following description, for example, "the continuous passage 52 adjacent to the divided storage unit 5A" is changed to the "divided storage unit 5A". It is expressed as "arranged continuous passage 52".

As shown in FIG. 15, in the fuel gas storage unit 11, the continuous passage 52 has the divided storage unit 5J as the inlet of the absorbing liquid 31 and the divided storage unit 5I as the outlet of the absorbing liquid 31, and the divided storage unit 5J is divided. The storage unit 5E, the divided storage unit 5D, the divided storage unit 5C, the divided storage unit 5B, the divided storage unit 5A, the divided storage unit 5F, the divided storage unit 5G, the divided storage unit 5H, and the divided storage unit 5I all pass through in series in this order. It is arranged like this.

In FIG. 15, the gas flow path 51 (not shown in FIG. 15) in the fuel gas storage unit 11 is arbitrarily connected, but the divided storage unit 5J in the lower right of the fuel gas storage unit 11 is a gas flow. It is the most upstream of the road 51, and the divided storage portion 5A on the upper left in the figure is the most downstream of the gas flow path 51.

As described above, the heat of adsorption / release of ethane, propane, butane (hereinafter referred to as butane, etc.) is higher than the heat of adsorption / release of methane. Therefore, butane and the like are more easily adsorbed on the adsorbent 111 and less likely to be released than methane.

For example, when the fuel gas is filled in the fuel gas storage unit 11 as shown in FIG. 15, butane and the like are concentratedly adsorbed on the divided storage unit 5J, but a large heat of adsorption is generated in the divided storage unit 5J. However, when the fuel gas is filled in the fuel gas storage unit 11, carbon dioxide is released from the absorption liquid 31, and the absorption liquid 31 is cooled by the heat released at that time. Therefore, since the absorption liquid 31 is first supplied to the communication passage 52 arranged in the divided storage unit 5J in the fuel gas storage unit 11, the heat of adsorption generated by the adsorbent 111 by the low temperature absorption liquid 31 is efficiently used. It is possible to take it out and suppress a decrease in adsorption efficiency of butane and the like.

On the contrary, when the fuel gas is discharged from the fuel gas storage unit 11, a large amount of heat is required to release butane or the like from the divided storage unit 5J. However, at this time, the absorption liquid 31 is filled with carbon dioxide, and the absorption liquid 31 is heated by the heat of adsorption at that time. Therefore, since the absorption liquid 31 is first supplied to the communication passage 52 arranged in the divided storage unit 5J in the fuel gas storage unit 11, it is necessary for the high-temperature absorption liquid 31 to release butane and the like from the adsorbent 111. The amount of heat can be efficiently supplied, and the decrease in the release efficiency of butane and the like can be suppressed.

[Modification example of fuel gas storage unit 11 and circulation path 3]
FIG. 16 is a schematic diagram showing a modified example of the fuel gas storage unit 11 and the circulation path 3 (communication passage 52).

In the modified example shown in FIG. 16, in the fuel gas storage unit 11, the divided storage unit 5J has the divided storage unit 5J as the inlet of the absorbing liquid 31 and the divided storage unit 5F has the outlet of the absorbing liquid 31, and the divided storage unit 5J, The divided storage unit 5E, the divided storage unit 5D, the divided storage unit 5C, the divided storage unit 5B, the divided storage unit 5A, and the divided storage unit 5F are arranged so as to pass through in series in this order.

Further, a communication passage 52a is arranged in the fuel gas storage unit 11. In the fuel gas storage unit 11, the communication passage 52a has the divided storage unit 5I as the inlet of the absorption liquid 31 and the divided storage unit 5G as the outlet of the absorption liquid 31, and the divided storage unit 5I, the divided storage unit 5H, and the divided storage unit. They are arranged so as to pass through in series in the order of 5G. The continuous passage 52a may have the same diameter as the continuous passage 52, or may be different in diameter.

Correspondingly, the circulation path 3a branches from between the temperature sensor T1 of the circulation path 3 and the introduction side of the absorption liquid 31 of the fuel gas storage section 11, and the temperature sensor T2 of the circulation path 3 and the fuel gas storage section The circulation path 3b branches from the discharge side of the absorption liquid 31 of 11.

Then, the circulation path 3a is connected to the end portion arranged in the divided storage portion 5I of the continuous passage 52a, and the circulation path 3b is connected to the end portion arranged in the divided storage portion 5G of the continuous passage 52a.

The continuous passage 52a has a shorter path length than the continuous passage 52. Therefore, since the amount of heat exchange differs between the vicinity of the downstream of the communication passage 52 and the vicinity of the downstream of the communication passage 52a, the temperatures between the two are different from each other. Therefore, in FIG. 16, at least the temperatures of the divided storage unit 5F and the divided storage unit 5G are different from each other. By forming the communication passages 52 and the communication passages 52a having different path lengths in this way, it is possible to form an arbitrary temperature distribution in the fuel gas storage unit 11. Further, here, the continuous passage 52 and the continuous passage 52a are branched into two, but the continuous passage 52 may be branched into a plurality of branches by branching into three or more. Further, the diameter of the connecting passage 52a is set to be the same so that the temperature of the absorbing liquid 31 flowing through the circulation path 3b and the temperature of the absorbing liquid 31 immediately after being discharged from the divided storage portion 5F in the circulation path 3 are the same. It may be smaller than the diameter of.

Further, when the circulation path 3 is branched into a plurality of parts as described above, the outside of the fuel gas storage unit 11 (for example, the circulation path 3a and the circulation path 3b) and the inside of the fuel gas storage unit 11 (for example, the communication passage 52b). A flow rate adjusting valve (not shown) is arranged in either of them, and the flow rate of the absorbing liquid 31 flowing through the circulation path 3 (continuous passage 52) and the flow rate of the absorbing liquid 31 flowing through the circulation path 3a and the circulation path 3b (continuous passage 52a). A configuration (rectification mechanism) in which the ratio can be arbitrarily set may be constructed.

Therefore, according to the modification, the communication passage 52 is branched into a plurality of passages, and the flow rate of the absorbing liquid 31 in the communication passage 52 (communication passage 52a) branched into the communication passage 52 or the circulation path 3 is increased. A rectifying mechanism that can adjust the ratio is provided. This makes it possible to form an arbitrary temperature distribution in the fuel gas storage unit 11.

11 Fuel gas storage 111 Adsorbent 31 Absorbent liquid 100 Adsorption storage system

Claims (15)

A fuel gas storage unit filled with an adsorbent that can store and release fuel gas,
Contains an absorbent that circulates in the fuel gas storage and can store and release carbon dioxide.
A fuel gas adsorption storage system in which the fuel gas storage unit and the absorption liquid are thermally connected to each other. A circulation path in which a communication passage inside the fuel gas storage unit is incorporated and filled with the absorption liquid, and
The fuel gas adsorption and storage system according to claim 1, further comprising a circulation pump for circulating the absorption liquid in the circulation path. The communication passage is branched into a plurality of passages, and the communication passage or the circulation path is provided with a rectifying mechanism capable of adjusting the ratio of the flow rate of the absorbed liquid in the communication passages that are branched into the plurality of passages. Item 2. The fuel gas adsorption storage system according to Item 2. The fuel gas adsorption and storage system according to claim 2 or 3, wherein a gas-liquid mixing device for absorbing carbon dioxide is arranged in the circulation path. The circulation pump is arranged between the outlet side of the gas-liquid mixing device of the circulation path and the introduction side of the absorption liquid of the fuel gas storage unit.
4. A defoaming device for preventing cavitation is arranged at a position of the circulation path between the discharge side of the absorption liquid of the gas-liquid mixing device and the introduction side of the absorption liquid of the circulation pump. The fuel gas adsorption and storage system described in. The fuel gas adsorption and storage system according to claim 4 or 5, which is connected to a fuel utilization device that consumes the fuel gas and emits an exhaust gas containing carbon dioxide. In
A fuel supply valve arranged in a path communicating the fuel gas introduction side of the fuel utilization device and the fuel gas discharge side of the fuel gas storage unit.
A separation device that extracts carbon dioxide from the exhaust gas discharged from the fuel utilization equipment, and
A carbon dioxide introduction valve arranged in a path connecting the carbon dioxide discharge side of the separation device and the carbon dioxide introduction side of the gas-liquid mixing device.
A first temperature sensor that measures the temperature between the discharge side of the absorption liquid of the circulation pump and the introduction side of the absorption liquid of the fuel gas storage unit in the circulation path.
A second temperature sensor that measures the temperature between the discharge side of the absorption liquid of the fuel gas storage portion of the circulation path and the introduction side of the absorption liquid of the gas-liquid mixing device.
The temperature information of the first temperature sensor and the second temperature sensor is input, and the circulation pump, the fuel supply valve, and the control unit for controlling the carbon dioxide introduction valve are provided.
The control unit
The fuel supply valve and the carbon dioxide introduction valve are opened, and the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is equal to or less than a predetermined temperature difference. A fuel gas adsorption and storage system that controls the output of the circulation pump or controls the opening degree of the carbon dioxide introduction valve. A first gas-liquid separation device arranged at a position between the discharge side of the absorption liquid of the fuel gas storage unit of the circulation path and the introduction side of the absorption liquid of the gas-liquid mixing device.
An exhaust valve arranged on the carbon dioxide exhaust side of the first gas-liquid separator,
A pressure sensor arranged at a position between the discharge side of the absorption liquid of the fuel gas storage portion of the circulation path and the introduction side of the absorption liquid of the first gas-liquid separation device is provided.
The fuel gas adsorption and storage system according to claim 6, wherein the control unit opens the exhaust valve when the pressure detected by the pressure sensor exceeds a predetermined pressure. A fuel filling valve arranged in a path connecting the fuel gas introduction side of the fuel gas storage unit and the external supply facility in which the fuel gas is stored.
A first gas-liquid separator arranged between the absorption liquid discharge side of the fuel gas storage unit of the circulation path and the absorption liquid introduction side of the gas-liquid mixing device.
An exhaust valve arranged on the carbon dioxide exhaust side of the first gas-liquid separator,
A first temperature sensor that measures the temperature between the discharge side of the absorption liquid of the circulation pump and the introduction side of the absorption liquid of the fuel gas storage unit in the circulation path.
A second temperature sensor that measures the temperature between the discharge side of the absorption liquid of the fuel gas storage portion of the circulation path and the introduction side of the absorption liquid of the first gas-liquid separation device.
The temperature information of the first temperature sensor and the second temperature sensor is input, and the circulation pump, the fuel filling valve, and the control unit for controlling the exhaust valve are provided.
The control unit
While opening the fuel filling valve and the exhaust valve, the circulation is such that the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is equal to or less than a predetermined temperature difference. The fuel gas adsorption and storage system according to claim 4 or 5, wherein the output of the pump is controlled or the opening degree of the exhaust valve is controlled. A carbon dioxide storage tank that is connected to the carbon dioxide emission side of the exhaust valve and can store carbon dioxide,
7. The claim 7 or claim includes a first booster interposed between the exhaust valve and the carbon dioxide storage tank to boost the carbon dioxide discharged from the exhaust valve and supply the carbon dioxide to the carbon dioxide storage tank. 8. The fuel gas adsorption and storage system according to 8. The fuel gas adsorption according to any one of claims 1 to 9, wherein the absorption liquid has a higher heat of adsorption of carbon dioxide than the heat of adsorption of another gas and can selectively absorb carbon dioxide. Storage system. The fuel gas adsorption and storage system according to any one of claims 4 to 9, wherein the gas-liquid mixing device is an ejector. The fuel gas according to claim 11, wherein the circulation pump is arranged at a position between the discharge side of the absorption liquid of the fuel gas storage unit and the introduction side of the absorption liquid of the ejector in the circulation path. Adsorption storage system. The fuel gas adsorption and storage system according to claim 5, which is connected to a fuel utilization device that consumes fuel gas and emits exhaust gas containing carbon dioxide, and the heat of adsorption of carbon dioxide in the absorption liquid is generated. In a fuel gas adsorption and storage system that can selectively absorb carbon dioxide higher than the heat of adsorption of other gases.
A dehumidifier that is arranged in a path connecting the exhaust gas discharge side of the fuel utilization device and the exhaust gas introduction side of the gas-liquid mixing device to remove water from the exhaust gas.
Exhaust gas mixed in the absorption liquid, which is arranged at a position between the discharge side of the absorption liquid of the defoaming device and the introduction side of the absorption liquid of the circulation pump in the circulation path, is dioxide. A fuel gas adsorption and storage system comprising a second gas-liquid separation device capable of separating components other than carbon from the absorption liquid. The fuel gas adsorption and storage system according to claim 5, wherein the fuel gas adsorption and storage system is connected to a fuel utilization device that consumes the fuel gas and emits an exhaust gas containing carbon dioxide.
A separation device that extracts carbon dioxide from the exhaust gas discharged from the fuel utilization equipment, and
A second booster that boosts carbon dioxide supplied from the separation device and supplies it to the gas-liquid mixing device.
A first gas-liquid separator arranged between the absorption liquid discharge side of the fuel gas storage unit of the circulation path and the absorption liquid introduction side of the gas-liquid mixing device.
The absorption liquid disposed between the discharge side of the absorption liquid of the fuel gas storage unit of the circulation path and the introduction side of the absorption liquid of the first gas-liquid separation device and discharged from the fuel gas storage unit. A fuel gas adsorption and storage system including a first pressure regulating valve that reduces pressure and supplies it to the first gas-liquid separation device. The absorption that is arranged between the discharge side of the absorption liquid of the first gas-liquid separation device and the introduction side of the absorption liquid of the gas-liquid mixing device in the circulation path and discharged from the first gas-liquid separation device. The fuel gas adsorption and storage system according to claim 14, further comprising a second pressure regulating valve that depressurizes the liquid and supplies it to the gas-liquid mixing device.

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