Supercritical carbon dioxide cycle power generation system occupying small space

Abstract

The invention discloses a supercritical carbon dioxide cycle power generation system occupying small space, which is characterized in that a cooling gas storage tank, a compressor shaft end and a turbine shaft end are respectively communicated with an inlet of a motor cavity through pipelines, and an inlet and an outlet of a heat exchanger are respectively communicated with an outlet of the motor cavity and an inlet of an adsorption tower through pipelines; a working medium outlet of the adsorption tower is communicated with an inlet of the cooler through a pipeline, a cooling gas outlet of the adsorption tower is communicated with an inlet of the motor cavity through a pipeline, and vacuum pumps are connected to the pipeline between the adsorption tower and the cooler and the pipeline between the adsorption tower and the generator. The problems that when an existing unit uses CO2 as cooling gas, the pressure of a generator motor cavity is difficult to increase, and supercharging equipment is large in size and high in energy consumption are effectively solved. Meanwhile, separation and recycling of the working medium and the cooling gas are achieved, the working medium entering the circulation is highly pure, and the unit performance of the power generation system is effectively guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of supercritical carbon dioxide power generation, and in particular to a supercritical carbon dioxide circulation power generation system with small space occupation. Background Art

[0002] The SCO2 cycle power generation system is an advanced thermal power generation technology that uses CO2 in a supercritical state as a working fluid. Compared with traditional steam turbine power generation systems, the SCO2 cycle has significant advantages of small size, light weight, fast start-up and high efficiency, and can achieve efficient energy conversion in a small space. However, the SCO2 cycle power generation system also faces some technical challenges. In particular, CO2 is often used as motor cooling gas in oil-free integrated SCO2 units, but SCO2 has a large density. If the pressure of the generator motor cavity is increased in order to reduce the size of the boosting equipment and reduce power consumption, the wind friction loss inside the motor will increase sharply, causing a significant decrease in motor efficiency. This problem limits the effectiveness of the SCO2 cycle in practical applications and urgently needs to be solved through technological innovation. Summary of the invention

[0003] In view of the above technical problems, the purpose of the present invention is to provide a supercritical carbon dioxide circulation power generation system with small space occupancy, which effectively solves the problems of difficulty in increasing the pressure in the generator motor cavity and large size and high energy consumption of the boosting equipment that cannot be overcome when the existing units use CO2 as cooling gas.

[0004] The space-saving supercritical carbon dioxide cycle power generation system according to the present invention comprises a cooler, a heater, a compressor, a turbine and a generator, wherein the generator has a motor cavity, and the system further comprises:

[0005] A cooling gas storage tank, wherein the cooling gas storage tank, the compressor shaft end, and the turbine shaft end are respectively connected to the inlet of the motor cavity through pipelines to form a mixed gas for cooling in the motor cavity;

[0006] A reinjection unit, the reinjection unit includes a heat exchanger and at least two adsorption towers, the inlet and outlet of the heat exchanger are connected to the outlet of the motor cavity and the inlet of the adsorption tower through pipelines respectively, the adsorption tower has an adsorbent, the adsorbent is used to separate the working fluid and cooling gas in the mixed gas, the working fluid outlet of the adsorption tower is connected to the inlet of the cooler through a pipeline, the cooling gas outlet of the adsorption tower is connected to the inlet of the motor cavity through a pipeline, and a vacuum pump is connected to the pipeline between the adsorption tower and the cooler and the pipeline between the adsorption tower and the generator.

[0007] In some embodiments, the adsorption tower uses pressure swing adsorption to treat the mixed gas.

[0008] In some embodiments, the reinjection unit includes two adsorption towers, which can be connected through a pipeline, and each adsorption tower undergoes the steps of pressurization, adsorption, equal pressure drop, vacuuming, and equal pressure increase.

[0009] In some embodiments, the cooling gas collected and stored in the cooling gas storage tank is helium.

[0010] In some embodiments, an air pressure sensor is provided in the motor cavity, and the air pressure sensor is electrically connected to a control device, and the control device controls the opening of the cooling gas storage tank outlet regulating valve based on air pressure data collected by the air pressure sensor.

[0011] In some embodiments, a regenerator is further included, and the regenerator is respectively connected to the compressor, the turbine, the heater and the cooler through pipelines.

[0012] In some embodiments, filters are provided on the pipeline connecting the compressor and the generator and on the pipeline connecting the turbine and the generator.

[0013] In some embodiments, the compressor, turbine and generator are an integrated coaxial structure.

[0014] In some embodiments, the adsorbent includes any one of activated carbon, molecular sieves, or calcium hydroxide, or a combination of at least two thereof.

[0015] In some embodiments, the adsorption process of an adsorption tower is as follows:

[0016] Adsorption: After the first adsorption tower completes the pressurization, the mixed gas continues to enter the first adsorption tower, the CO2 in the mixed gas is adsorbed by the adsorbent, and the cooling gas flows from the adsorption tower side to the generator side;

[0017] Both pressure reduction: When the adsorption tower is saturated, the two adsorption towers are connected, at this time the pressure of the adsorption tower is reduced and the pressure of the other adsorption tower is increased;

[0018] Vacuuming: After the pressure reduction is completed, the adsorption tower is evacuated by a vacuum pump. At this time, the pressure of the adsorption tower is reduced, the adsorbed CO2 is desorbed from the adsorbent, and the adsorbent is regenerated to prepare for the next adsorption. The desorbed CO2 flows from the adsorption tower side to the cooler side;

[0019] Equalizing pressure increase: After vacuuming, the two adsorption towers are connected, and part of the high-pressure gas in the other adsorption tower is used to increase the pressure of the adsorption tower.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention proposes a supercritical carbon dioxide circulation power generation system with small space occupation. The cooling gas can be helium, which has a low density under high pressure, and can effectively reduce the wind wear loss caused by the high pressure of the generator motor cavity, so that the generator can maintain a high operating efficiency, and can greatly reduce the structural size of the vacuum pump, thereby reducing the space occupied by the overall power generation system. At the same time, the mixed gas at the outlet of the generator motor cavity is separated by an adsorption tower, so that the separation and recycling of the working medium and the cooling gas are realized. The working medium entering the cycle is highly pure, which effectively guarantees the unit performance of the power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The preferred implementation modes will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present invention.

[0023] Figure 1 It is a schematic structural diagram of a supercritical carbon dioxide circulation power generation system with small space occupation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0025] Any substance has three phases: solid, liquid and gas. Under certain temperature and pressure, the phase of the substance will change, thus showing different phases. Among them, the point where the gas and liquid phases are in equilibrium is called the critical point. The temperature and pressure corresponding to the critical point are called the critical temperature and critical pressure respectively. The state of the substance at the critical point is called the critical state. If the temperature and pressure of the substance in the critical state continue to rise, when the temperature and pressure exceed the critical temperature and critical pressure, the substance no longer has a phase boundary between liquid and gas, and presents properties between liquid and gas, that is, the substance enters the supercritical state.

[0026] When the temperature and pressure of CO2 reach its critical temperature of 31.1℃ and critical pressure of 7.38Mpa respectively, CO2 will be in a supercritical state, that is, SCO2. SCO2 is between liquid and gas, and has the special physical properties of low gas viscosity and high liquid density, which gives it typical advantages such as good fluidity, high heat transfer efficiency, and low compressibility. Using SCO2 as a circulating working fluid for power generation has the characteristics of wide applicable heat sources, compact structure, low compression power consumption, and high cycle efficiency. It has the advantages of efficiency, volume, and flexibility that traditional steam power generation cannot match. It has broad application prospects in the fields of solar thermal utilization, coal-fired power generation, nuclear power generation, waste heat utilization, ship propulsion, etc. It is a new generation of high-efficiency, low-cost, and environmentally friendly advanced energy technology.

[0027] Figure 1 This is a schematic diagram of the structure of a supercritical carbon dioxide cycle power generation system with small space occupation in an embodiment of the present invention. Figure 1 As shown, a supercritical carbon dioxide circulation power generation system with small space occupation in an embodiment of the present invention includes a power generation unit and a reinjection unit.

[0028] The power generation unit is used to generate electricity using SCO2 as a working medium, and the power generation unit includes a compressor 1, a turbine 2, a generator 3, a regenerator 5 and a heater 6. The compressor 1, the turbine 2 and the generator 3 constitute a main engine system, which are fixed on the same rotating shaft, and the generator 3 is located between the turbine 2 and the compressor 1.

[0029] The compressor 1 is used to increase the low-pressure working medium to a high-pressure working medium. The compressor 1 can be a screw compressor 1, a centrifugal compressor 1, an axial flow compressor 1, or a centrifugal + axial flow compressor 1, etc., which are not limited here. The compressor 1 is connected to the regenerator 5 through a pipeline 11. In the pipeline 11, the working medium flows from the compressor 1 side to the regenerator 5 side.

[0030] The regenerator 5 is also called a gas-liquid heat exchanger. Generally, the regenerator 5 is a container with two ends open, and its interior is filled with different fillers, such as metal mesh, metal balls with very small diameters, etc., and heat exchange is achieved by switching between cold and hot air flows. The regenerator 5 has two functions in the SCO2 cycle. One is to heat the working fluid at the outlet of the compressor 1, save fuel, and improve thermal efficiency. The other is to reduce the temperature of the working fluid at the outlet of the turbine 2, reduce the use of cooling water, save water resources, and reduce the energy consumption of the compressor 1. In a possible implementation, the regenerator 5 can be a printed circuit board type regenerator. The regenerator 5 is connected to the heater 6 and the cooler 8 through the pipeline 12 and the pipeline 17 respectively. In the pipeline 12, the working fluid flows from the regenerator 5 side to the heater 6 side. In the pipeline 17, the working fluid flows from the regenerator 5 side to the cooler 8 side.

[0031] The heater 6 is used to heat the circulating working medium. The energy source of the heater 6 can be industrial waste heat, nuclear reactors, fossil fuels or solar energy, etc. In a possible implementation, the heater 6 can be a gas boiler heater. The heater 6 is connected to the turbine 2 through a pipeline 13. In the pipeline 13, the working medium flows from the heater 6 side to the turbine 2 side.

[0032] The cooler 8 is used to cool the working medium. The cooler 8 usually uses water or air as a coolant to remove heat. The cooler 8 can be a partition cooler, a spray cooler, a printed circuit board cooler, a jacket cooler or a coil cooler, etc., which are not limited here. The cooler 8 is connected to the compressor 1 through a pipeline 18. In the pipeline 18, the working medium flows from the cooler 8 side to the compressor 1 side.

[0033] The turbine 2 is also called a turbine, an expander, etc. It is a rotary power device. The high-temperature and high-pressure working fluid expands in the turbine 2, converting the thermal energy of the working fluid into mechanical energy, while doing work externally. When the working fluid expands and accelerates in the turbine 2, the pressure and temperature decrease, and the speed increases. The turbine 2 is connected to the regenerator 5 through the pipeline 14. In the pipeline 14, the working fluid flows from the turbine 2 side to the regenerator 5 side.

[0034] The generator 3 refers to a device that converts mechanical energy into electrical energy using the law of electromagnetic induction. The generator 3 can be various forms of synchronous generators 3, asynchronous generators 3, single-phase generators 3, three-phase generators 3, etc., and is not limited here.

[0035] In this embodiment, CO2 that enables the supercritical carbon dioxide circulation system to operate at full power can be pre-filled in the above pipelines. The regenerator 5 and the heater 6 are used to heat the high-pressure CO2 to obtain high-temperature and high-pressure supercritical carbon dioxide SCO2, and the high-temperature and high-pressure SCO2 is delivered to the turbine 2. The high-temperature and high-pressure SCO2 drives the turbine 2 to rotate, thereby driving the compressor 1 to rotate. The regenerator 5 is also used to pre-cool the SCO2 output from the turbine 2, and deliver the pre-cooled SCO2 to the cooler 8 for cooling. The compressor 1 is used to pressurize the SCO2 cooled by the cooler 8. When the outlet pressure of the compressor 1 is higher than its inlet pressure, the turbine 2 drives the compressor 1 and the generator 3 to rotate simultaneously, so that the generator 3 generates electricity.

[0036] The power generation unit may also include a cooling gas storage tank 7, which is a tank for collecting and storing cooling gas. The cooling gas may be He (helium), the molecular weight of He is much smaller than that of CO2, and the density of He is still relatively low under high pressure, which can effectively reduce the wind wear loss caused by the high pressure in the motor cavity of the generator, so that the generator maintains a high operating efficiency, and can greatly reduce the structural size of the vacuum pump 10, thereby reducing the occupied space of the overall power generation system. In addition, the thermal conductivity of He is more than ten times that of CO2, which is beneficial to improving the cooling efficiency when used for cooling the motor cavity of the generator. Furthermore, the chemical properties of helium are extremely inactive and will not corrode the generator, which can ensure the service life of the generator and the reliability of the system. The cooling gas storage tank 7 is connected to the generator 3 through a pipeline 20, and in the pipeline 20, the cooling gas flows from the cooling gas storage tank 7 side to the generator 3 side.

[0037] Cooling gas can be supplied to the motor cavity of the generator 3 through the cooling gas storage tank 7. The cooling gas exchanges heat with the gas in the motor cavity of the generator 3, which can help control the temperature in the motor cavity of the generator 3, improve the cooling efficiency of the generator 3, and enable the generator 3 to maintain a stable operating temperature under high load conditions, thereby stabilizing the power generation efficiency of the generator 3.

[0038] An air pressure sensor is provided in the motor cavity of the generator 3, and the air pressure sensor is used to measure the air pressure in the motor cavity of the generator 3. The air pressure sensor is electrically connected to a control device (not shown). The control device controls the opening of the cooling gas storage tank outlet regulating valve connected to the pipeline 20 based on the air pressure data collected by the air pressure sensor.

[0039] The air pressure in the motor cavity of the generator 3 is controlled in the following manner: after the control device receives data from the air pressure sensor, it compares the received real-time air pressure data with the preset high air pressure data and low air pressure data. When the real-time air pressure data reaches the preset high air pressure data, the control device calculates the atmosphere pressure in the cavity of the generator 3, and calculates the opening of the cooling gas storage tank outlet regulating valve based on the acquired data, and changes or maintains the opening of the cooling gas storage tank outlet regulating valve based on the calculated result. For example, when the atmosphere pressure in the cavity of the generator 3 is low, the opening value of the cooling gas storage tank outlet regulating valve is set to a large value, and when the atmosphere pressure in the cavity of the generator 3 is high, the opening value of the cooling gas storage tank outlet regulating valve is set to a large value.

[0040] During the operation of the power generation unit, a small amount of working fluid will leak from the shaft ends of the compressor 1 and the turbine 2. In order to achieve zero leakage of the working fluid to the outside, the working fluid leaking from the shaft ends of the compressor 1 and the turbine 2 can be introduced into the motor cavity of the generator 3 for recovery. In a feasible embodiment, the compressor 1 is connected to the generator 3 through a pipeline 16, and the turbine 2 is connected to the generator 3 through a pipeline 12. In the pipeline 16, the working fluid leaking from the shaft end of the compressor 1 flows from the compressor 1 side to the motor cavity side of the generator 3. In the pipeline 15, the working fluid leaking from the shaft end of the turbine 2 flows from the turbine 2 side to the motor cavity side of the generator 3. Filters can also be set on the pipelines 15 and 16, and the filters are used to filter out bearing lubricating oil and other impurities that may exist in the leaked working fluid.

[0041] It can be understood that the working fluid leaking from the shaft ends of the compressor 1 and the turbine 2, and the cooling gas supplied by the cooling gas storage tank 7 meet in the motor cavity of the generator 3 to form a mixed gas. Since the leaked working fluid flow rate is much smaller than the cooling gas flow rate, the temperature of the cooling gas will not change significantly.

[0042] If the circulating working fluid contains impurities, it will affect the performance of the power generation unit. In order to ensure the efficient operation of the power generation unit, the working fluid must be highly pure. Based on this, the reinjection unit is used to separate the working fluid and cooling gas from the mixed gas, and respectively make the working fluid and cooling gas participate in the fully closed cycle.

[0043] The reinjection unit includes a heat exchanger and at least two adsorption towers 9 .

[0044] The heat exchanger 4 is used to cool the mixed gas. The heat exchanger 4 usually uses water or air as a coolant to remove heat. The heat exchanger 4 can be a partition heat exchanger, a spray heat exchanger, a printed circuit board heat exchanger, a jacket heat exchanger or a coil heat exchanger, etc., which are not limited here. The heat exchanger 4 is connected to the motor cavity of the generator 3 through the pipeline 19. In the pipeline 19, the mixed gas flows from the generator 3 side to the heat exchanger 4 side.

[0045] The adsorption tower 9 is used to separate the working fluid and the cooling gas in the mixed gas. A packed bed is provided in the adsorption tower 9. The packed bed is filled with an adsorbent. The material of the adsorbent is not specifically limited in the embodiment of the present invention. As long as it can adsorb carbon dioxide and does not react chemically with it, and can also desorb carbon dioxide after depressurization, it can be used. For example, the material of the adsorbent is selected from activated carbon, molecular sieve, calcium hydroxide, etc., and one of them can be used, or two or more substances can be used at the same time.

[0046] The adsorption tower 9 is connected with pipelines 111-114, pipeline 111 is a pipeline connecting the heat exchanger 4 and the adsorption tower 9, in which the mixed gas flows from the heat exchanger 4 side to the adsorption tower 9 side, pipeline 112 is a pipeline connecting the two adsorption towers 9, in which the gas flows from one adsorption tower to the other adsorption tower, pipeline 113 is a pipeline connecting the adsorption tower 9 and the cooler 8, in which the working medium flows from the adsorption tower 9 side to the cooler 8 side, pipeline 114 is a pipeline connecting the adsorption tower 9 and the motor cavity of the generator 3, in which the cooling gas flows from the adsorption tower 9 side to the generator 3 side.

[0047] It should be noted that the pipelines mentioned in this embodiment are all provided with control valves.

[0048] The adsorption tower 9 in this embodiment uses a pressure swing adsorption method to treat the mixed gas. Taking two adsorption towers 9 as an example, the cycle sequence of the adsorption process of the two towers is shown in Table 1. Each adsorption tower 9 must go through five process steps of pressurization, adsorption, pressure drop, vacuum, and pressure rise. In order to distinguish, the two adsorption towers 9 are defined as the first adsorption tower and the second adsorption tower, respectively. The adsorption process of the first adsorption tower is as follows:

[0049] Pressurization: Open the valve on the pipeline 111 connecting the first adsorption tower and the heat exchanger 4, and the mixed gas flows from the heat exchanger 4 side to the first adsorption tower side through the pipeline 111;

[0050] Adsorption: After the first adsorption tower completes the pressurization, the mixed gas continues to enter the first adsorption tower, and the CO2 in the mixed gas is adsorbed by the adsorbent. At the same time, the valve on the pipeline 114 is opened, and the cooling gas flows from the first adsorption tower side to the generator 3 side through the pipeline 114;

[0051] Pressure reduction: When the first adsorption tower is saturated with adsorption, close the valve on the pipeline 114 and the valve on the pipeline 111 between the first adsorption tower and the heat exchanger 4, and open the valve on the pipeline 112 to connect the two adsorption towers 9. At this time, the pressure of the first adsorption tower is reduced, and the pressure of the second adsorption tower is increased;

[0052] Vacuuming: After the pressure reduction is completed, the valve on the pipeline 112 is closed, and the valve on the pipeline 113 between the first adsorption tower and the heat exchanger 4 is opened. The first adsorption tower is evacuated by the vacuum pump 10. At this time, the pressure of the first adsorption tower is reduced, the adsorbed CO2 is desorbed from the adsorbent, and the adsorbent is regenerated to prepare for the next adsorption. The desorbed CO2 flows from the first adsorption tower side to the cooler 8 side through the pipeline 113;

[0053] Equalizing the pressure: After vacuuming, close the valve on the pipeline 113 between the first adsorption tower and the heat exchanger 4, open the valve on the pipeline 112, connect the two adsorption towers 9, and use part of the high-pressure gas in the second adsorption tower to increase the pressure of the first adsorption tower.

[0054] Table 1 Cycle timing

[0055]

[0056] The space-saving supercritical carbon dioxide circulation power generation system proposed in the present invention effectively solves the problems of difficulty in increasing the pressure of the generator motor cavity and large volume and high energy consumption of the boosting equipment, which cannot be overcome when the existing units use CO2 as cooling gas. At the same time, the mixed gas at the outlet of the generator motor cavity is separated by pressure swing adsorption, which realizes the separation and recycling of the working fluid and the cooling gas. Compared with other separation technologies, it has outstanding cold source adaptability, and the adsorption and purification effect is not affected by changes in ambient temperature. The generator motor cavity maintains high pressure, and the PSA device operates under high pressure conditions, which further improves the purification and separation efficiency.

[0057] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A supercritical carbon dioxide cycle power generation system with small space occupation, comprising a cooler, a heater, a compressor, a turbine and a generator, wherein the generator has a motor cavity, characterized in that: Also includes: A cooling gas storage tank, wherein the cooling gas storage tank, the compressor shaft end, and the turbine shaft end are respectively connected to the inlet of the motor cavity through pipelines to form a mixed gas for cooling in the motor cavity, and the cooling gas collected and stored in the cooling gas storage tank is helium; A reinjection unit, the reinjection unit includes a heat exchanger and at least two adsorption towers, the inlet and outlet of the heat exchanger are connected to the outlet of the motor cavity and the inlet of the adsorption tower through pipelines respectively, the adsorption tower has an adsorbent for separating the working fluid and the cooling gas in the mixed gas, the working fluid outlet of the adsorption tower is connected to the working fluid inlet of the cooler through a pipeline, the cooling gas outlet of the adsorption tower is connected to the inlet of the motor cavity through a pipeline, and a vacuum pump is connected to the pipeline between the adsorption tower and the cooler and the pipeline between the adsorption tower and the generator.

2. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: The adsorption tower uses a pressure swing adsorption method to treat the mixed gas.

3. The space-saving supercritical carbon dioxide cycle power generation system according to claim 2 is characterized in that: The reinjection unit includes two adsorption towers, which can be connected through a pipeline, and each adsorption tower undergoes the steps of pressurization, adsorption, equal pressure drop, vacuuming, and equal pressure increase.

4. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: An air pressure sensor is provided in the motor cavity, and the air pressure sensor is electrically connected to the control device. The control device controls the opening of the cooling gas storage tank outlet regulating valve based on the air pressure data collected by the air pressure sensor.

5. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: It also includes a heat regenerator, which is connected to the compressor, turbine, heater and cooler through pipelines respectively.

6. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: Filters are arranged on the pipeline connecting the compressor and the generator and the pipeline connecting the turbine and the generator.

7. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: The compressor, turbine and generator are an integrated coaxial structure.

8. The space-saving supercritical carbon dioxide cycle power generation system according to claim 1 is characterized in that: The adsorbent is any one of activated carbon, molecular sieve or calcium hydroxide or a combination of at least two of them.

9. The space-saving supercritical carbon dioxide cycle power generation system according to claim 3 is characterized in that: The adsorption process of an adsorption tower is as follows: Adsorption: After the first adsorption tower completes the pressurization, the mixed gas continues to enter the first adsorption tower, the CO2 in the mixed gas is adsorbed by the adsorbent, and the cooling gas flows from the adsorption tower side to the generator side; Both pressure reduction: When the adsorption tower is saturated, the two adsorption towers are connected, at this time the pressure of the adsorption tower is reduced and the pressure of the other adsorption tower is increased; Vacuuming: After the pressure reduction is completed, the adsorption tower is evacuated by a vacuum pump. At this time, the pressure of the adsorption tower is reduced, the adsorbed CO2 is desorbed from the adsorbent, and the adsorbent is regenerated to prepare for the next adsorption. The desorbed CO2 flows from the adsorption tower side to the cooler side; Equalizing pressure increase: After vacuuming, the two adsorption towers are connected, and part of the high-pressure gas in the other adsorption tower is used to increase the pressure of the adsorption tower.

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