Methanol washing tail gas treatment and carbon dioxide energy storage coupling system

Abstract

The utility model relates to the technical field of new energy, and provides a methanol washing tail gas treatment and carbon dioxide energy storage coupling system which comprises a methanol washing tail gas supply unit, an air supply unit, a purification reaction unit and a carbon dioxide energy storage unit. Wherein the methanol washing tail gas supply unit and the air supply unit are both connected with the purification reaction unit and used for conveying methanol washing tail gas and air into the purification reaction unit, the purification reaction unit is connected with the carbon dioxide energy storage unit, and the carbon dioxide energy storage unit is connected with the methanol washing tail gas supply unit. And carbon dioxide generated after the purification reaction is stored in the carbon dioxide energy storage unit. Through the system structure arrangement, the methanol washing tail gas treatment module and the carbon dioxide energy storage module are coupled, so that methanol washing tail gas and air are subjected to oxidation reaction in the purification reaction unit to produce carbon dioxide and water, and the carbon dioxide generated by the reaction is stored in the carbon dioxide energy storage unit to be supplied as required. Therefore, energy waste caused in the methanol washing tail gas treatment process can be avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, in particular to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage. Background Art

[0002] In the purification process of raw coal gas in coal gasification, the low-temperature methanol wash technology is mostly adopted. Its purification principle is to remove harmful impurities contained in the raw coal gas, such as H2S, COS, CO2, etc., by physical absorption method, so as to provide qualified raw gas for the subsequent process sections. During the preparation of the raw gas, a stream of CO2 tail gas will be continuously discharged from the top of the tail gas scrubbing tower in the low-temperature methanol wash process. This stream of CO2 tail gas contains some VOCs, and substances such as non-methane total hydrocarbons and methanol in it all exceed the latest national standard requirements, with potential risks such as explosion and pollution. This tail gas needs to be purified before being discharged into the atmosphere. Currently, most of the tail gas and fuel gas are mixed and then fed into a regenerative thermal oxidation device, so that the VOCs in the tail gas are mixed with the fuel gas for efficient oxidation reaction to generate carbon dioxide and water. In the prior art, the carbon dioxide generated after tail gas treatment is usually directly discharged, which will cause energy waste. Summary of the Utility Model

[0003] The utility model provides a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage to solve the above technical problems.

[0004] According to the utility model, a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage is provided, which includes a methanol wash tail gas feeding unit, an air feeding unit, a purification reaction unit and a carbon dioxide energy storage unit.

[0005] Wherein, the methanol wash tail gas feeding unit and the air feeding unit are both connected to the purification reaction unit and are used to respectively transport methanol wash tail gas and air into the purification reaction unit. The purification reaction unit is connected to the carbon dioxide energy storage unit to store the carbon dioxide generated after purification reaction into the carbon dioxide energy storage unit.

[0006] According to the coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the utility model, the purification reaction unit includes a combustion chamber, a burner, a fuel gas supply pipe and an auxiliary combustion gas supply pipe.

[0007] Wherein, the fuel gas supply pipe and the auxiliary combustion gas supply pipe are both connected to the burner. The burner is connected to the combustion chamber. The combustion chamber is connected to the air feeding unit. A plurality of regenerative reaction chambers are arranged at intervals in the combustion chamber. Each regenerative reaction chamber is connected to the methanol wash tail gas feeding unit.

[0008] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, a first fan is arranged between the fuel gas supply pipe and the combustion-supporting gas supply pipe and the burner. A first flow control valve is arranged on the fuel gas supply pipe. A second flow control valve is arranged on the combustion-supporting gas supply pipe.

[0009] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model. The methanol wash tail gas supply unit includes a methanol wash tail gas supply pipe and a second fan. The second fan is arranged on the methanol wash tail gas supply pipe. The inlets of the heat storage reaction chambers are all connected to the methanol wash tail gas supply pipe.

[0010] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, the methanol wash tail gas supply unit further includes a third fan and a carbon dioxide exhaust pipe. The outlets of the heat storage reaction chambers are all connected to the carbon dioxide exhaust pipe. The third fan is arranged on the carbon dioxide exhaust pipe. The carbon dioxide exhaust pipe is connected to the carbon dioxide energy storage unit.

[0011] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, a third flow control valve is arranged on the methanol wash tail gas supply pipe. Fourth flow control valves are correspondingly arranged between the inlets of the heat storage reaction chambers and the methanol wash tail gas supply pipe. A filter is further arranged on the methanol wash tail gas supply pipe.

[0012] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, the air supply unit includes an air supply pipe. The air supply pipe is communicated with the combustion chamber. A fifth flow control valve and a fourth fan are arranged on the air supply pipe.

[0013] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, the carbon dioxide energy storage unit includes a shunt, a finished carbon dioxide storage tank and a carbon dioxide energy storage power generation unit.

[0014] Wherein, the third fan is connected to the finished carbon dioxide storage tank and the carbon dioxide energy storage power generation unit through the shunt.

[0015] According to a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, the carbon dioxide energy storage power generation unit includes a water cooler, a dryer, a low-pressure carbon dioxide storage tank, a sixth flow control valve, a compressor, a cooler, a liquefier, a high-pressure liquid carbon dioxide storage tank, a seventh flow control valve, a vaporizer, a heater, an expander and a post-cooler.

[0016] Among them, the diverter is connected to the water cooler. The water cooler is connected to the dryer. The dryer is connected to the low-pressure carbon dioxide storage tank. The low-pressure carbon dioxide storage tank is connected to the compressor. The sixth flow control valve is arranged between the low-pressure carbon dioxide storage tank and the compressor. The compressor is connected to the cooler. The cooler is connected to the liquefier. The liquefier is connected to the high-pressure liquid carbon dioxide storage tank. The high-pressure liquid carbon dioxide storage tank is connected to the vaporizer. The seventh flow control valve is arranged between the high-pressure liquid carbon dioxide storage tank and the vaporizer. The vaporizer is connected to the heater. The heater is connected to the expander. The expander is connected to the aftercooler. The aftercooler is connected to the low-pressure carbon dioxide storage tank.

[0017] According to a methanol wash tail gas treatment and carbon dioxide energy storage coupling system provided by the present utility model, the carbon dioxide energy storage unit further includes a low-temperature storage tank and a high-temperature storage tank. The heat exchange medium outlet of the heater is connected to the inlet of the low-temperature storage tank. The outlet of the low-temperature storage tank is connected to the heat exchange medium inlet of the cooler. The heat exchange medium outlet of the cooler is connected to the inlet of the high-temperature storage tank. The outlet of the high-temperature storage tank is connected to the heat exchange medium inlet of the heater.

[0018] In the methanol wash tail gas treatment and carbon dioxide energy storage coupling system provided by the present utility model, it includes a methanol wash tail gas feeding unit, an air feeding unit, a purification reaction unit and a carbon dioxide energy storage unit. Among them, both the methanol wash tail gas feeding unit and the air feeding unit are connected to the purification reaction unit. The methanol wash tail gas feeding unit and the air feeding unit are respectively used for feeding methanol wash tail gas and air into the purification reaction unit. The methanol wash tail gas and air can undergo an oxidation reaction in the purification reaction unit to produce carbon dioxide and water. The purification reaction unit is connected to the carbon dioxide energy storage unit to store the carbon dioxide generated by the reaction in the carbon dioxide energy storage unit and supply it when needed.

[0019] Through this system structure setting, the methanol wash tail gas treatment module and the carbon dioxide energy storage module are coupled. The methanol wash tail gas and air undergo an oxidation reaction in the purification reaction unit to produce carbon dioxide and water, and the carbon dioxide generated by the reaction is stored in the carbon dioxide energy storage unit and supplied when needed. Thus, the energy waste caused during the methanol wash tail gas treatment process can be avoided. Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the present utility model or the prior art, the following will briefly introduce the attached drawings required in the description of the embodiments or the prior art. Obviously, the attached drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other attached drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a schematic structural diagram of the methanol wash tail gas treatment and carbon dioxide energy storage coupling system provided by the present utility model.

[0022] Reference numerals: 110, combustion chamber; 111, regenerative reaction chamber; 120, burner; 130, fuel gas supply pipe; 140, combustion-supporting gas supply pipe; 150, first fan; 160, first flow control valve; 170, second flow control valve; 210, methanol wash tail gas supply pipe; 220, second fan; 230, third fan; 240, carbon dioxide exhaust pipe; 250, third flow control valve; 260, fourth flow control valve; 270, filter; 310, air supply pipe; 320, fifth flow control valve; 330, fourth fan; 410, diverter; 420, finished carbon dioxide storage tank; 510, water cooler; 520, dryer; 530, low-pressure carbon dioxide storage tank; 610, sixth flow control valve; 620, compressor; 630, cooler; 640, liquefier; 650, high-pressure liquid carbon dioxide storage tank; 710, seventh flow control valve; 720, vaporizer; 730, heater; 740, expander; 750, aftercooler; 810, high-temperature storage tank; 820, low-temperature storage tank. Detailed implementation manners

[0023] The following will further describe in detail the implementation manners of the present utility model in conjunction with the attached drawings and embodiments. The following embodiments are used to illustrate the present utility model, but cannot be used to limit the scope of the present utility model.

[0024] In the description of the embodiments of the present utility model, it should be noted that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the attached drawings. These are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0025] In the description of the embodiments of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0026] In the embodiments of the present utility model, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0027] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model.

[0028] The following is combined with Figure 1 A methanol wash tail gas treatment and carbon dioxide energy storage coupling system provided by the embodiments of the present utility model will be described. It should be understood that the following is only a schematic implementation manner of the present utility model and does not constitute any special limitation to the present utility model.

[0029] An embodiment of the present utility model provides a coupling system for methanol wash tail gas treatment and carbon dioxide energy storage, as Figure 1 shown. The coupling system for methanol wash tail gas treatment and carbon dioxide energy storage includes a methanol wash tail gas supply unit, an air supply unit, a purification reaction unit, and a carbon dioxide energy storage unit.

[0030] Among them, both the methanol wash tail gas supply unit and the air supply unit are connected to the purification reaction unit and are used to separately transport methanol wash tail gas and air into the purification reaction unit. The purification reaction unit is connected to the carbon dioxide energy storage unit to store the carbon dioxide generated after purification reaction into the carbon dioxide energy storage unit.

[0031] In the coupling system for methanol wash tail gas treatment and carbon dioxide energy storage provided by the present utility model, it includes a methanol wash tail gas supply unit, an air supply unit, a purification reaction unit, and a carbon dioxide energy storage unit. Among them, both the methanol wash tail gas supply unit and the air supply unit are connected to the purification reaction unit. The methanol wash tail gas supply unit and the air supply unit are respectively used to transport methanol wash tail gas and air into the purification reaction unit. The methanol wash tail gas and air can undergo an oxidation reaction in the purification reaction unit to produce carbon dioxide and water. The purification reaction unit is connected to the carbon dioxide energy storage unit to store the carbon dioxide generated by the reaction into the carbon dioxide energy storage unit and supply it as needed when required.

[0032] Through this system structure setting, the methanol wash tail gas treatment module and the carbon dioxide energy storage module are coupled, enabling the methanol wash tail gas and air to undergo an oxidation reaction in the purification reaction unit to produce carbon dioxide and water, and storing the carbon dioxide generated by the reaction into the carbon dioxide energy storage unit and supplying it as needed when required. Thereby, the energy waste caused during the methanol wash tail gas treatment process can be avoided.

[0033] In an embodiment of the present utility model, as Figure 1 shown, the purification reaction unit includes a combustion chamber 110, a burner 120, a fuel gas supply pipe 130, and a combustion-supporting gas supply pipe 140.

[0034] Among them, both the fuel gas supply pipe 130 and the combustion-supporting gas supply pipe 140 are connected to the burner 120. The burner 120 is connected to the combustion chamber 110. The combustion chamber 110 is connected to the air supply unit. A plurality of heat storage reaction chambers 111 are arranged at intervals in the combustion chamber 110. Each heat storage reaction chamber 111 is connected to the methanol wash tail gas supply unit.

[0035] In an embodiment of the present utility model, as Figure 1As shown, a first blower 150 is provided between the fuel gas supply pipe 130 and the combustion-supporting gas supply pipe 140 and the burner 120. A first flow control valve 160 is provided on the fuel gas supply pipe 130. A second flow control valve 170 is provided on the combustion-supporting gas supply pipe 140.

[0036] In an embodiment of the present invention, as Figure 1 shown, the methanol scrubbing tail gas supply unit includes a methanol scrubbing tail gas supply pipe 210 and a second blower 220. The second blower 220 is provided on the methanol scrubbing tail gas supply pipe 210, and the inlets of the respective regenerative reaction chambers 111 are all connected to the methanol scrubbing tail gas supply pipe 210.

[0037] In an embodiment of the present invention, as Figure 1 shown, the methanol scrubbing tail gas supply unit further includes a third blower 230 and a carbon dioxide exhaust pipe 240. The outlets of the respective regenerative reaction chambers 111 are all connected to the carbon dioxide exhaust pipe 240. The third blower 230 is provided on the carbon dioxide exhaust pipe 240. The carbon dioxide exhaust pipe 240 is connected to the carbon dioxide energy storage unit.

[0038] In an embodiment of the present invention, as Figure 1 shown, a third flow control valve 250 is provided on the methanol scrubbing tail gas supply pipe 210. A fourth flow control valve 260 is correspondingly provided between the inlet of each regenerative reaction chamber 111 and the methanol scrubbing tail gas supply pipe 210. A filter 270 is also provided on the methanol scrubbing tail gas supply pipe 210.

[0039] Furthermore, in an embodiment of the present invention, as Figure 1 shown, the air supply unit includes an air supply pipe 310. The air supply pipe 310 communicates with the combustion chamber 110, and a fifth flow control valve 320 and a fourth blower 330 are provided on the air supply pipe 310.

[0040] In the specific working process, the fuel gas supply pipe 130 and the combustion-supporting gas supply pipe 140 are respectively used to supply fuel gas and high-temperature combustion-supporting gas into the burner 120. The fuel gas and the high-temperature combustion-supporting gas are input into the burner 120 under the action of the first blower 150 for combustion, so as to generate a large amount of heat and input it into the combustion chamber 110, thereby providing a high-temperature environment for the combustion chamber 110. Among them, the first flow control valve 160 and the second flow control valve 170 can adjust the intake amounts of the fuel gas and the high-temperature combustion-supporting gas, so that the fuel gas and the high-temperature combustion-supporting gas are fully mixed, which is more conducive to their combustion in the burner 120. The combustion chamber 110 is used for the oxidation reaction of the tail gas from the methanol washing process in a high-temperature environment. A plurality of regenerative reaction chambers 111 are arranged at intervals in the combustion chamber 110. The regenerative reaction chambers 111 are mostly honeycomb ceramic regenerators. The high-temperature gas generated by oxidation flows through the ceramic regenerator, causing the ceramic regenerator to heat up and store heat. This stored heat is used to preheat the subsequent incoming tail gas from the methanol washing process, thereby saving the fuel consumption for heating the tail gas from the methanol washing process.

[0041] The tail gas from the methanol washing process enters the regenerative reaction chamber 111 through the tail gas supply pipe 210 of the methanol washing process and the second blower 220, and the clean air enters the combustion chamber 110 through the air supply pipe 310 and the fourth blower 330. The tail gas from the methanol washing process undergoes a high-temperature oxidation reaction in the combustion chamber 110 and generates carbon dioxide and water. The clean air can purge the regenerative reaction chamber 111 to ensure the removal rate of volatile organic compounds, and then a new round of purification treatment is carried out. Among them, carbon dioxide can be transported to the carbon dioxide energy storage unit through the carbon dioxide exhaust pipe 240 and the third blower 230 for storage, so as to be supplied when needed. Among them, a filter 270 is arranged on the tail gas supply pipe 210 of the methanol washing process to filter out solid particles and other impurities in the tail gas from the methanol washing process. A third flow control valve 250 and a fifth flow control valve 320 are respectively arranged on the tail gas supply pipe 210 of the methanol washing process and the air supply pipe 310. The third flow control valve 250 and the fifth flow control valve 320 are respectively used to control the intake amounts of the tail gas from the methanol washing process and the clean air, so as to make the oxidation reaction more complete. In addition, a fourth flow control valve 260 is correspondingly arranged between the inlet of each regenerative reaction chamber 111 and the tail gas supply pipe 210 of the methanol washing process, so that the tail gas from the methanol washing process can be slowly and continuously switched in multiple regenerative reaction chambers 111 under the distribution action of each fourth flow control valve 260, making the oxidation reaction more complete.

[0042] In an embodiment of the present invention, the carbon dioxide energy storage unit includes a diverter 410, a finished carbon dioxide storage tank 420 and a carbon dioxide energy storage power generation unit.

[0043] Among them, the third blower 230 is connected to the finished carbon dioxide storage tank 420 and the carbon dioxide energy storage power generation unit through the diverter 410.

[0044] In an embodiment of the present utility model, as Figure 1 shown, the carbon dioxide energy storage power generation unit includes a water cooler 510, a dryer 520, a low-pressure carbon dioxide storage tank 530, a sixth flow control valve 610, a compressor 620, a cooler 630, a liquefier 640, a high-pressure liquid carbon dioxide storage tank 650, a seventh flow control valve 710, a vaporizer 720, a heater 730, an expander 740, and a post-cooler 750.

[0045] Among them, the diverter 410 is connected to the water cooler 510. The water cooler 510 is connected to the dryer 520. The dryer 520 is connected to the low-pressure carbon dioxide storage tank 530. The low-pressure carbon dioxide storage tank 530 is connected to the compressor 620. The sixth flow control valve 610 is disposed between the low-pressure carbon dioxide storage tank 530 and the compressor 620. The compressor 620 is connected to the cooler 630. The cooler 630 is connected to the liquefier 640. The liquefier 640 is connected to the high-pressure liquid carbon dioxide storage tank 650. The high-pressure liquid carbon dioxide storage tank 650 is connected to the vaporizer 720. The seventh flow control valve 710 is disposed between the high-pressure liquid carbon dioxide storage tank 650 and the vaporizer 720. The vaporizer 720 is connected to the heater 730. The heater 730 is connected to the expander 740. The expander 740 is connected to the post-cooler 750. The post-cooler 750 is connected to the low-pressure carbon dioxide storage tank 530.

[0046] Specifically, the carbon dioxide energy storage unit includes two processes: energy storage and energy release for power generation. The third fan 230 transports the carbon dioxide output from the carbon dioxide exhaust pipe 240 to the diverter 410. The diverter 410 can divert the carbon dioxide gas to the finished carbon dioxide storage tank 420 and the carbon dioxide energy storage power generation unit. The carbon dioxide gas flowing into the carbon dioxide energy storage unit first passes through the water cooler 510 for cooling, then enters the dryer 520 for drying, and is then temporarily stored in the low-pressure carbon dioxide storage tank 530. The low-pressure carbon dioxide storage tank 530 can be an airbag. By adjusting the opening degree of the sixth flow control valve 610, the low-pressure gaseous carbon dioxide in the low-pressure carbon dioxide storage tank 530 can reach a high-temperature and high-pressure state after being compressed by the compressor 620. Among them, the compressor 620 is driven by abandoned electricity or grid valley electricity. Subsequently, the high-temperature and high-pressure carbon dioxide enters the cooler 630 for cooling. The cooler 630 can be a plate cooler 630, which can enable the high-pressure and high-temperature gaseous carbon dioxide to exchange heat with the heat storage medium in the cooler 630. After cooling, the carbon dioxide is cooled to room temperature. At the same time, the heat generated during the cooling process can be stored in the heat storage working medium inside it. The high-pressure and room-temperature carbon dioxide gas enters the liquefier 640 for liquefaction. The liquefier 640 can lower the temperature of the carbon dioxide below the carbon dioxide critical point. At this time, the carbon dioxide is transformed from a gaseous state to a liquid state and enters the high-pressure carbon dioxide storage tank for storage. The high-pressure carbon dioxide storage tank can be a steel storage tank or a gas storage pipeline. When energy release for power generation is required, the seventh flow control valve 710 is opened to an appropriate opening degree. The liquid carbon dioxide stored in the high-pressure carbon dioxide storage tank first enters the vaporizer 720 for vaporization. Subsequently, the gaseous carbon dioxide enters the heater 730 for heating up to reach a high-temperature and high-pressure state, and then enters the expander 740 to drive the impeller of the expander 740 to do work. The expander 740 drives the generator to generate electricity. The carbon dioxide after expanding and doing work by the expander 740 returns to the low-pressure carbon dioxide storage tank 530 after being cooled by the aftercooler 750.

[0047] In an embodiment of the present invention, the carbon dioxide energy storage unit further includes a low-temperature storage tank 820 and a high-temperature storage tank 810. The heat exchange medium outlet of the heater 730 is connected to the inlet of the low-temperature storage tank 820. The outlet of the low-temperature storage tank 820 is connected to the heat exchange medium inlet of the cooler 630. The heat exchange medium outlet of the cooler 630 is connected to the inlet of the high-temperature storage tank 810. The outlet of the high-temperature storage tank 810 is connected to the heat exchange medium inlet of the heater 730.

[0048] Among them, the high-temperature storage tank 810 and the low-temperature storage tank 820 can be horizontal, vertical pressure vessels or spherical tanks. Heat insulation materials and adiabatic outer shells need to be provided outside the high-temperature storage tank 810 for encapsulation. The heat storage working medium in the heat storage and release cycle can be water, heat-conducting oil and other low-melting-point liquid materials.

[0049] During the energy storage process, the low-pressure carbon dioxide stored in the low-pressure carbon dioxide storage tank 530 enters the compressor 620 and is compressed to a high-pressure and high-temperature state. Then it is cooled in the cooler 630, and the heat is transferred to the heat storage working fluid of the cooler 630. Subsequently, it enters the liquefier 640 and is cooled again until it is completely liquefied, and is stored in the high-pressure liquid carbon dioxide storage tank 650 in the form of high-pressure and high-density liquid. During this process, the heat storage working fluid in the cooler 630 is raised from a low-temperature state to a high-temperature state and stored in the high-temperature storage tank 810. This process can be understood as the conversion of electrical energy into the thermal energy of the heat storage working fluid and the pressure energy of carbon dioxide.

[0050] During the energy release process, the carbon dioxide stored in the high-pressure liquid carbon dioxide storage tank 650 is vaporized by the vaporizer 720 to a gaseous state, and then the gaseous carbon dioxide is further heated in the heater 730. The heat for this process comes from the high-temperature heat stored in the heat storage working fluid in the high-temperature storage tank 810. The carbon dioxide heated to the preset temperature enters the expander 740 to expand and do work, driving the generator to output electrical energy. The carbon dioxide after expansion work is low-pressure carbon dioxide, which returns to the low-pressure carbon dioxide storage tank 530 after being cooled by the aftercooler 750. During this process, the heat storage working fluid in the heater 730 becomes a low-temperature state after heat exchange from a high-temperature state and is stored in the low-temperature storage tank 820. The carbon dioxide also drops from a high-pressure state to a low-pressure state. This process can be understood as the conversion of the thermal energy of the heat storage working fluid and the pressure energy of carbon dioxide into electrical energy.

[0051] According to the embodiments described above, in the methanol wash tail gas treatment and carbon dioxide energy storage coupling system, since the methanol wash tail gas contains some VOCs, it will pollute the environment when directly discharged. Through the treatment of the purification reaction unit, the concentration of volatile organic compounds in the tail gas can be greatly reduced to meet the national standards. At the same time, it can also be combined with the carbon dioxide energy storage system to achieve the purpose of carbon dioxide reuse. Due to the characteristics that the carbon dioxide critical point is easily reached, the carbon dioxide energy storage technology makes the system have a higher energy density compared with other compressed gas energy storage systems. At the same time, this system only involves the phase change of carbon dioxide and has no chemical reactions, so it is also safer. In addition, this system is more compact. Due to the high energy density and good thermodynamic properties of carbon dioxide, the liquid carbon dioxide energy storage system can be designed to be more compact, greatly reducing the floor area and infrastructure costs. This system has strong adaptability, and the methanol wash tail gas can also be extended to other high-concentration carbon dioxide tail gases for impurity removal and purification. It is not restricted by geographical conditions and can be deployed in a variety of environments, with high promotion value.

[0052] By organically coupling the methanol wash tail gas treatment process with carbon dioxide energy storage, the problems of ineffective treatment of large-flow and high-concentration tail gas and the inability to utilize carbon dioxide can be solved. The tail gas is treated by regenerative thermal oxidation to become high-purity carbon dioxide, which is then connected to a carbon dioxide energy storage system to provide gas source conditions for the system and will not be directly discharged into the atmosphere, having good social benefits. Moreover, during the energy storage stage of the carbon dioxide energy storage system, discarded electricity or valley electricity is used, and at the same time, the heat generated by compression is absorbed by the circulating heat storage working medium. During the peak electricity consumption period, energy is released without external heat source energy input and heat supplement, and the system has a high cycle efficiency and good economic benefits.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A methanol washing tail gas treatment and carbon dioxide energy storage coupling system, characterized in that: It includes methanol-washed tail gas supply unit, air supply unit, purification reaction unit and carbon dioxide energy storage unit. Among them, the methanol washing tail gas supply unit and the air supply unit are both connected to the purification reaction unit, and are used to respectively transport methanol washing tail gas and air into the purification reaction unit. The purification reaction unit is connected to the carbon dioxide energy storage unit to store the carbon dioxide generated after the purification reaction in the carbon dioxide energy storage unit.

2. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 1 is characterized in that: The purification reaction unit comprises a combustion chamber (110), a burner (120), a fuel gas supply pipe (130) and a combustion-supporting gas supply pipe (140). The fuel gas supply pipe (130) and the combustion-supporting gas supply pipe (140) are both connected to the burner (120), the burner (120) is connected to the combustion chamber (110), the combustion chamber (110) is connected to the air supply unit, a plurality of regenerative reaction chambers (111) are arranged at intervals in the combustion chamber (110), and each of the regenerative reaction chambers (111) is connected to the methanol-washed tail gas supply unit.

3. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 2 is characterized in that: A first fan (150) is provided between the fuel gas supply pipe (130) and the combustion-supporting gas supply pipe (140) and the burner (120); a first flow control valve (160) is provided on the fuel gas supply pipe (130); and a second flow control valve (170) is provided on the combustion-supporting gas supply pipe (140).

4. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 2 or 3, characterized in that: The methanol-washed tail gas supply unit comprises a methanol-washed tail gas supply pipe (210) and a second fan (220), wherein the second fan (220) is arranged on the methanol-washed tail gas supply pipe (210), and the inlet of each of the thermal storage reaction chambers (111) is connected to the methanol-washed tail gas supply pipe (210).

5. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 4 is characterized in that: The methanol-washed tail gas supply unit further comprises a third fan (230) and a carbon dioxide exhaust pipe (240); the outlet of each of the thermal storage reaction chambers (111) is connected to the carbon dioxide exhaust pipe (240); the third fan (230) is arranged on the carbon dioxide exhaust pipe (240); and the carbon dioxide exhaust pipe (240) is connected to the carbon dioxide energy storage unit.

6. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 5 is characterized in that: A third flow control valve (250) is provided on the methanol-washed tail gas supply pipe (210), a fourth flow control valve (260) is correspondingly provided between the inlet of each of the thermal storage reaction chambers (111) and the methanol-washed tail gas supply pipe (210), and a filter (270) is also provided on the methanol-washed tail gas supply pipe (210).

7. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 6 is characterized in that: The air supply unit comprises an air supply pipe (310), the air supply pipe (310) is in communication with the combustion chamber (110), and a fifth flow control valve (320) and a fourth fan (330) are provided on the air supply pipe (310).

8. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 7 is characterized in that: The carbon dioxide energy storage unit comprises a flow divider (410), a finished carbon dioxide storage tank (420) and a carbon dioxide energy storage power generation unit. The third fan (230) is connected to the finished carbon dioxide storage tank (420) and the carbon dioxide energy storage power generation unit via the diverter (410).

9. The methanol washing tail gas treatment and carbon dioxide energy storage coupling system according to claim 8 is characterized in that: The carbon dioxide energy storage power generation unit comprises a water cooler (510), a dryer (520), a low-pressure carbon dioxide storage tank (530), a sixth flow control valve (610), a compressor (620), a cooler (630), a liquefier (640), a high-pressure liquid carbon dioxide storage tank (650), a seventh flow control valve (710), a vaporizer (720), a heater (730), an expander (740) and an aftercooler (750). The diverter (410) is connected to the water cooler (510), the water cooler (510) is connected to the dryer (520), the dryer (520) is connected to the low-pressure carbon dioxide storage tank (530), the low-pressure carbon dioxide storage tank (530) is connected to the compressor (620), the sixth flow control valve (610) is arranged between the low-pressure carbon dioxide storage tank (530) and the compressor (620), the compressor (620) is connected to the cooler (630), the cooler (630) is connected to the liquefier (640), and the liquefier (640) is connected to the low-pressure carbon dioxide storage tank (530). The device (640) is connected to the high-pressure liquid carbon dioxide storage tank (650), the high-pressure liquid carbon dioxide storage tank (650) is connected to the vaporizer (720), the seventh flow control valve (710) is arranged between the high-pressure liquid carbon dioxide storage tank (650) and the vaporizer (720), the vaporizer (720) is connected to the heater (730), the heater (730) is connected to the expander (740), the expander (740) is connected to the aftercooler (750), and the aftercooler (750) is connected to the low-pressure carbon dioxide storage tank (530).

10. The methanol-washed tail gas treatment and carbon dioxide energy storage coupling system according to claim 9, characterized in that: The carbon dioxide energy storage unit further includes a low-temperature storage tank (820) and a high-temperature storage tank (810), the heat exchange medium outlet of the heater (730) is connected to the inlet of the low-temperature storage tank (820), the outlet of the low-temperature storage tank (820) is connected to the heat exchange medium inlet of the cooler (630), the heat exchange medium outlet of the cooler (630) is connected to the inlet of the high-temperature storage tank (810), and the outlet of the high-temperature storage tank (810) is connected to the heat exchange medium inlet of the heater (730).

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