A gas-thermal co-storage system and its operation method

Abstract

This invention provides a gas-thermal co-storage system and its operation method, belonging to the field of energy storage technology. The gas-thermal co-storage system includes an adsorption tower, a fan, and a heat exchanger. The adsorption tower contains a carbon dioxide adsorbent. A first pipeline connects the outlet of the adsorption tower to the inlet of the fan, which is connected to the outlet of the adsorption tower via the first pipeline. The outlet of the fan is connected to the first inlet of the heat exchanger via a second pipeline. The first outlet of the heat exchanger is connected to the inlet of the adsorption tower via a third pipeline. The heat exchanger also has a second inlet and a second outlet. This invention can stabilize the temperature-changing section by controlling the fan speed and the temperature of the gas entering the adsorption tower, thereby ensuring stable exhaust or storage gas temperature and flow rate. It solves the problems of nonlinear heating of the adsorbent and nonlinear adsorption and desorption, meets the gas volume requirements of upstream and downstream equipment, and simplifies the control strategy of the gas-thermal co-storage system.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and more specifically, to a gas-thermal co-storage system and its operation method. Background Technology

[0002] A gas-thermal co-storage system is a device that achieves low-pressure, high-density gas storage by adsorbing and storing gas using an adsorbent. The system adsorbs and stores gas at normal temperature and pressure (1 bar, 303 K), and then releases the gas by heating the adsorbent to a high temperature (1 bar, 473 K), thus achieving joint storage and supply of gas and heat. This system can solve the low-pressure CO2 storage problem in compressed CO2 energy storage systems, while also storing and utilizing the heat of compression generated during the compression process. Since the compressor's gas intake needs to remain stable during compression, the gas-thermal co-storage system must be able to provide a stable gas supply.

[0003] The adsorption of CO2 by the adsorbent used in the gas-thermal co-storage system is a type of physical adsorption, and the amount of adsorption changes non-linearly with temperature. If it is desired to achieve stable gas output by controlling the overall temperature of the adsorbent through global heating, it is necessary to frequently adjust the heating power to regulate the heating rate of the adsorbent, thereby controlling the output gas volume of the gas-thermal control system.

[0004] Currently, the heat sources used in gas-heat co-storage systems are the compression heat of the compressor in the compressed CO2 energy storage system and the waste heat from the flue gas of the power plant. They are usually supplied at a constant temperature and heat, making it difficult to control the heating power of the gas-heat co-storage system. Therefore, if a global heating scheme is used for the gas-heat co-storage system, the adsorbent temperature will rise in a non-linear manner, which will lead to unstable exhaust and gas storage flow of the gas-heat co-storage system. Summary of the Invention

[0005] The problem solved by this invention is how to address the issues of nonlinear heating and nonlinear adsorption and desorption of the adsorbent in a gas-thermal co-storage system, thereby achieving stability in exhaust temperature and exhaust and storage gas flow rates.

[0006] To address the aforementioned problems, the present invention provides a gas-heat co-storage system, comprising an adsorption tower, a fan, and a heat exchanger. The adsorption tower is equipped with a carbon dioxide adsorbent for adsorbing and desorbing carbon dioxide gas, the fan is used to circulate the carbon dioxide gas, and the heat exchanger is used for heat exchange.

[0007] The adsorption tower has a first pipeline at its outlet, the fan inlet is connected to the adsorption tower outlet through the first pipeline, the fan outlet is connected to the heat exchanger inlet through a second pipeline, the heat exchanger outlet is connected to the adsorption tower inlet through a third pipeline, and the heat exchanger is also provided with a second inlet and a second outlet.

[0008] Preferably, the gas-heat co-storage system further includes a compressor, the compressor's inlet being connected to the adsorption tower's outlet via a fourth pipeline, the compressor's outlet being connected to the heat exchanger's second inlet via a fifth pipeline, and the heat exchanger's second outlet being connected to the outside via a sixth pipeline.

[0009] Preferably, the gas-heat co-storage system further includes an expander, the second outlet of the heat exchanger is connected to the inlet of the expander via a seventh pipeline, and the outlet of the expander is connected to the inlet of the adsorption tower via an eighth pipeline.

[0010] This invention comprises an adsorption tower, a fan, a heat exchanger, and connecting pipelines to form a gas-heat co-storage system. The adsorption tower contains a carbon dioxide adsorbent. Under low-temperature conditions, the adsorbent adsorbs carbon dioxide gas, while under high-temperature conditions, the carbon dioxide gas desorbs from the adsorbent. Part of the desorbed gas passes sequentially through a first pipeline, a fan, a second pipeline, a heat exchanger, and a third pipeline. After circulation and heat exchange, it forms gas that meets the temperature requirements and re-enters the adsorption tower. The other part is supplied to the outside. The second inlet and second outlet of the heat exchanger are used to input and output high-temperature or low-temperature media, which exchange heat with the high-temperature or high-temperature carbon dioxide gas entering the heat exchanger. After the high-temperature or low-temperature carbon dioxide gas enters the adsorption tower, a high-temperature section, a variable-temperature section, and a low-temperature section can be formed inside the adsorption tower. By controlling the fan speed and stabilizing the gas temperature entering the adsorption tower, the variable-temperature section can be ensured to move forward at a stable speed, thereby achieving stable exhaust temperature and exhaust flow. This solves the problems of nonlinear heating of the adsorbent and nonlinear adsorption and desorption of the adsorbent, meets the gas volume requirements of upstream and downstream equipment, and simplifies the control strategy of the gas-heat co-storage system.

[0011] On the other hand, the present invention also provides an operation method for a gas-heat co-storage system, based on the gas-heat co-storage system described above, comprising:

[0012] Step S1: By controlling the wind speed of the fan, high-temperature carbon dioxide gas or low-temperature carbon dioxide gas enters the adsorption tower, forming a high-temperature section, a variable-temperature section and a low-temperature section. In the initial stage, the initial length of the variable-temperature section is less than or equal to 15% of the total length of the adsorption tower.

[0013] Step S2: During operation, by controlling the wind speed of the fan and the temperature of the gas entering the inlet of the adsorption tower to keep stable, the variable temperature section moves forward at a constant speed, and the exhaust or storage gas flow rate and exhaust or storage gas temperature at the outlet of the adsorption tower are kept stable.

[0014] Preferably, in step S1, the temperature of the high-temperature carbon dioxide gas is 200°C, and the temperature of the low-temperature carbon dioxide gas is 30°C.

[0015] Preferably, in step S1, the temperature of the high-temperature section is 200°C, the temperature of the low-temperature section is 30°C, and the temperature of the variable-temperature section is greater than 30°C and less than 200°C.

[0016] Preferably, in step S2, during operation, by controlling the wind speed of the fan and the temperature of the gas entering the inlet of the adsorption tower to stabilize, the length change of the variable temperature section is less than or equal to 25% of the initial length, so that the variable temperature section moves forward at a uniform speed, and the exhaust flow rate and exhaust temperature of the adsorption tower outlet are kept stable.

[0017] Preferably, when the gas entering the adsorption tower is high-temperature carbon dioxide gas, step S2 includes:

[0018] During operation, the outlet of the adsorption tower stably discharges low-temperature carbon dioxide gas. Part of the discharged low-temperature carbon dioxide gas is compressed into high-temperature carbon dioxide gas and then enters the heat exchanger. The other part passes through the fan and the heat exchanger in sequence. The high-temperature carbon dioxide gas formed by the compressor exchanges heat with the low-temperature carbon dioxide gas circulated by the fan in the heat exchanger, so that the low-temperature carbon dioxide gas circulated by the fan becomes high-temperature carbon dioxide gas before entering the adsorption tower, keeping the temperature of the gas entering the adsorption tower and the gas entering the outside stable. By controlling the fan speed and the stable temperature of the gas entering the adsorption tower inlet, the variable temperature section moves forward at a uniform speed, keeping the outlet of the adsorption tower stably discharging low-temperature carbon dioxide gas and the exhaust flow rate stable.

[0019] Preferably, when the gas entering the adsorption tower is low-temperature carbon dioxide gas, step S2 includes:

[0020] During operation, the outlet of the adsorption tower stably discharges high-temperature carbon dioxide gas. The discharged high-temperature carbon dioxide gas passes sequentially through the fan and the heat exchanger, forming low-temperature carbon dioxide gas, which then re-enters the inlet of the adsorption tower for circulation. The low-temperature carbon dioxide gas entering from the outside exchanges heat with the high-temperature carbon dioxide gas entering the heat exchanger through the fan, forming high-temperature carbon dioxide gas. The high-temperature carbon dioxide gas discharged from the heat exchanger passes through the expander and forms low-temperature carbon dioxide gas, which then enters the inlet of the adsorption tower. By controlling the fan speed, the temperature of the gas discharged from the expander, and the gas entering the inlet of the adsorption tower, the variable temperature section is pushed forward at a uniform speed, ensuring that the adsorption tower stably adsorbs high-temperature carbon dioxide gas and that the gas storage flow rate is stable.

[0021] Preferably, when the gas entering the adsorption tower is high-temperature carbon dioxide gas at a temperature of 200°C, in step S2, when the exhaust temperature of the adsorption tower is 30°C, the exhaust flow rate of the adsorption tower is as shown in the second formula:

[0022] Q = ρ 30℃ *(N 200℃ -N 30℃ )*S*V;

[0023] Where Q is the exhaust flow rate of the adsorption tower, ρ 30℃ The density of the gas at normal pressure and 30°C is N. 200℃ This represents the mass of gas adsorbed per unit mass of adsorbent at 200℃, expressed in N. 30℃ The value represents the mass of gas adsorbed per unit mass of the adsorbent at 30°C, S is the cross-sectional area of ​​the adsorption tower, and V is the velocity of the temperature-changing section.

[0024] This invention controls the fan speed to ensure the amount of air entering the adsorption tower inlet, keeping the length of the initial temperature-changing section within 15% of the total length of the adsorption tower. This facilitates the uniform forward movement of the temperature-changing section within the adsorption tower by controlling the fan speed. During operation of the gas-thermal co-storage system, by controlling the fan speed and stabilizing the gas temperature entering the adsorption tower inlet, the temperature-changing section moves forward uniformly within the adsorption tower, ensuring a stable flow rate of desorbed or adsorbed gas within the adsorption tower. Ultimately, the flow rate and temperature of the gas discharged from the adsorption tower outlet remain stable, or the flow rate and temperature of the stored gas entering the adsorption tower inlet remain stable. This allows for matching the gas volume and temperature requirements of upstream and downstream equipment, intelligently regulating the intake and exhaust volumes of the gas-thermal co-storage system, and simplifying the control strategy of the gas-thermal co-storage system. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the gas-heat co-storage system in an embodiment of the present invention. Figure 1 ;

[0026] Figure 2 This is a schematic diagram of the gas-heat co-storage system in an embodiment of the present invention. Figure 2 ;

[0027] Figure 3 This is a schematic diagram of the temperature shift process during high-temperature desorption in an embodiment of the present invention. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below.

[0029] It should be noted that, where there is no conflict, the features in the embodiments of this invention can be combined with each other. Furthermore, in the accompanying drawings, the black arrows indicate the flow direction of high-temperature carbon dioxide gas, the gray arrows indicate the flow direction of low-temperature carbon dioxide gas, the black areas represent high-temperature sections, the gray areas represent low-temperature sections, and the areas where black transitions to gray represent temperature-varying sections.

[0030] This invention provides a gas-heat co-storage system, such as... Figure 1-2 As shown, it includes an adsorption tower, a fan, and a heat exchanger. The adsorption tower is equipped with a carbon dioxide adsorbent for adsorbing and desorbing carbon dioxide gas. The fan is used to circulate carbon dioxide gas, and the heat exchanger is used for heat exchange.

[0031] The adsorption tower has a first pipeline at its outlet. The fan inlet is connected to the adsorption tower outlet via the first pipeline. The fan outlet is connected to the heat exchanger's first inlet via a second pipeline. The heat exchanger's first outlet is connected to the adsorption tower inlet via a third pipeline. The heat exchanger also has a second inlet and a second outlet.

[0032] This invention provides a gas-heat co-storage system comprised of an adsorption tower, a fan, a heat exchanger, and connecting pipelines. The adsorption tower contains a carbon dioxide adsorbent. Under low-temperature conditions, the adsorbent adsorbs carbon dioxide gas, while under high-temperature conditions, the carbon dioxide gas desorbs from the adsorbent. Part of the desorbed gas passes sequentially through a first pipeline, a fan, a second pipeline, a heat exchanger, and a third pipeline. After circulation and heat exchange, it forms gas that meets the temperature requirements and re-enters the adsorption tower. The other part is supplied to the outside. The second inlet and second outlet of the heat exchanger are used to input and output high-temperature or low-temperature media, which exchange heat with the high-temperature or high-temperature carbon dioxide gas entering the heat exchanger. After the high-temperature or low-temperature carbon dioxide gas enters the adsorption tower, a high-temperature section, a variable-temperature section, and a low-temperature section are formed within the adsorption tower. By controlling the fan speed and stabilizing the gas temperature entering the adsorption tower, the variable-temperature section can be ensured to move forward at a stable speed, thereby achieving stable exhaust temperature and exhaust flow. This solves the problems of nonlinear heating of the adsorbent and nonlinear adsorption and desorption, meets the gas volume requirements of upstream and downstream equipment, and simplifies the control strategy of the gas-heat co-storage system.

[0033] In one embodiment, such as Figure 1 As shown, the gas-heat co-storage system also includes a compressor. The air inlet of the compressor is connected to the air outlet of the adsorption tower through a fourth pipeline. The air outlet of the compressor is connected to the second air inlet of the heat exchanger through a fifth pipeline. The second air outlet of the heat exchanger is connected to the outside through a sixth pipeline.

[0034] During the high-temperature desorption process, when high-temperature carbon dioxide gas enters the adsorption tower through the inlet, the carbon dioxide adsorbed in the adsorbent is desorbed. The adsorption tower sequentially forms a high-temperature section, a variable-temperature section, and a low-temperature section. In the high-temperature section, the carbon dioxide in the adsorbent is completely desorbed, in the variable-temperature section, the carbon dioxide in the adsorbent is partially desorbed, and in the low-temperature section, the carbon dioxide in the adsorbent has not yet been desorbed. The carbon dioxide gas desorbed in the high-temperature and variable-temperature sections gradually cools down after passing through the low-temperature section to form low-temperature carbon dioxide gas. After being compressed by the compressor, the low-temperature carbon dioxide gas generates heat of compression and forms high-temperature carbon dioxide gas. Through a heat exchanger, the high-temperature carbon dioxide gas generated by the compressor exchanges heat with the low-temperature carbon dioxide gas circulated by the fan to form high-temperature carbon dioxide gas again. The high-temperature carbon dioxide gas re-enters the adsorption tower to provide a stable gas supply. During this process, the variable-temperature section moves forward to ensure the stable operation of the gas-heat co-storage system.

[0035] In another embodiment, such as Figure 2 As shown, the gas-heat co-storage system also includes an expander. The second outlet of the heat exchanger is connected to the inlet of the expander through a seventh pipeline, and the outlet of the expander is connected to the inlet of the adsorption tower through an eighth pipeline.

[0036] For example, the outlet of the expander is connected between the first inlet of the heat exchanger and the inlet of the adsorption tower. The gas discharged from the expander and the gas discharged from the heat exchanger are combined and then enter the adsorption tower.

[0037] During the low-temperature adsorption process, when low-temperature carbon dioxide gas enters the adsorption tower through the inlet, the adsorbent adsorbs the low-temperature carbon dioxide gas. The adsorption tower sequentially forms a low-temperature section, a variable-temperature section, and a high-temperature section. The adsorbent in the low-temperature section is saturated with carbon dioxide, the adsorbent in the variable-temperature section has adsorbed some carbon dioxide gas, and the adsorbent in the high-temperature section has not yet adsorbed carbon dioxide. Due to the operation of the fan to maintain the pressure in the gas-heat co-storage system, some of the low-temperature carbon dioxide gas entering the adsorption tower is not adsorbed by the adsorbent. After passing through the low-temperature section, variable-temperature section, and high-temperature section in sequence, it heats up to form high-temperature carbon dioxide gas, which is discharged from the outlet of the adsorption tower. The discharged high-temperature carbon dioxide gas passes through the fan and heat exchanger in sequence, and after forming low-temperature carbon dioxide gas, it re-enters the adsorption tower through the inlet to provide stable gas supply to the adsorption tower. At the same time, the low-temperature carbon dioxide gas entering the heat exchanger from the outside exchanges heat with the high-temperature carbon dioxide gas circulating through the fan to form high-temperature carbon dioxide gas. After being expanded by the expander, it also forms low-temperature carbon dioxide gas, which enters the adsorption tower. During this process, the variable-temperature section moves forward to ensure the stable operation of the gas-heat co-storage system.

[0038] It should be noted that the heat exchanger includes two inlets and two outlets, which are used to achieve heat exchange between gases or media from different sources.

[0039] Another embodiment of the present invention provides an operation method for a gas-heat co-storage system, based on the gas-heat co-storage system described above, comprising:

[0040] Step S1: By controlling the wind speed of the fan, high-temperature carbon dioxide gas or low-temperature carbon dioxide gas enters the adsorption tower, forming a high-temperature section, a variable-temperature section and a low-temperature section. In the initial stage, the initial length of the variable-temperature section is less than or equal to 15% of the total length of the adsorption tower.

[0041] Step S2: During operation, by controlling the wind speed of the fan and the temperature of the gas entering the inlet of the adsorption tower to keep stable, the variable temperature section moves forward at a constant speed, and the exhaust or storage gas flow rate and exhaust or storage gas temperature at the outlet of the adsorption tower are kept stable.

[0042] This invention, through controlling the fan speed, ensures the amount of air entering the adsorption tower inlet, keeping the length of the initial temperature-changing section within 15% of the total length of the adsorption tower. This facilitates the uniform forward movement of the temperature-changing section within the adsorption tower by controlling the fan speed. During operation of the gas-thermal co-storage system, by controlling the fan speed and stabilizing the gas temperature entering the adsorption tower inlet, the temperature-changing section moves forward uniformly within the adsorption tower, ensuring a stable flow rate of desorbed or adsorbed gas within the adsorption tower. Ultimately, the flow rate and temperature of the gas discharged from the adsorption tower outlet remain stable, or the flow rate and temperature of the stored gas entering the adsorption tower inlet remain stable. This allows for matching the gas volume and temperature requirements of upstream and downstream equipment, intelligently regulating the intake and exhaust volumes of the gas-thermal co-storage system, and simplifying the control strategy of the gas-thermal co-storage system.

[0043] In the gas pressure co-storage system, the adsorbent adsorbs carbon dioxide gas at normal temperature and pressure (1 bar, 30°C), while heating it to normal pressure and high temperature (1 bar, 200°C) allows the carbon dioxide gas to desorb. Therefore, in step S1, the temperature of the high-temperature carbon dioxide gas is 200°C, and the temperature of the low-temperature carbon dioxide gas is 30°C.

[0044] When high-temperature carbon dioxide gas at 200℃ enters the adsorption tower, it can heat the adsorbent in the adsorption tower to 200℃, thereby desorbing the carbon dioxide gas adsorbed in the adsorbent. Correspondingly, when low-temperature carbon dioxide gas at 30℃ enters the adsorption tower, it can cool the adsorbent in the adsorption tower to 30℃, thereby allowing the adsorbent to adsorb the low-temperature carbon dioxide gas.

[0045] When the temperature of the high-temperature carbon dioxide gas is 200℃ and the temperature of the low-temperature carbon dioxide gas is 30℃, the temperature of the high-temperature section in the adsorption tower is 200℃, the temperature of the low-temperature section is 30℃, and the temperature of the variable-temperature section is greater than 30℃ and less than 200℃.

[0046] To ensure stable exhaust flow and exhaust temperature, in step S2, during operation, the fan speed and the gas temperature entering the adsorption tower inlet are controlled to ensure that the length change of the variable temperature section is less than or equal to 25% of the initial length, so that the variable temperature section moves forward at a uniform speed, and the exhaust flow and exhaust temperature at the adsorption tower outlet are kept stable.

[0047] In other words, by controlling the fan speed and the gas temperature entering the adsorption tower during operation to prevent large fluctuations and keeping the changes in fan speed and gas temperature within a small range, the gas temperature in the adsorption tower can be pushed forward at a uniform speed. During this process, the exhaust flow rate and exhaust temperature at the outlet of the adsorption tower fluctuate little, enabling a stable gas supply to the upstream or downstream.

[0048] The operation methods of the above-mentioned gas-thermal co-storage system during the high-temperature desorption process and the low-temperature adsorption process are described below.

[0049] During the high-temperature desorption process, specifically when the gas entering the adsorption tower is high-temperature carbon dioxide gas, step S2 includes:

[0050] During operation, the outlet of the adsorption tower stably discharges low-temperature carbon dioxide gas. Part of the discharged low-temperature carbon dioxide gas is compressed into high-temperature carbon dioxide gas and then enters the heat exchanger. The other part passes through the fan and the heat exchanger in sequence. The high-temperature carbon dioxide gas formed by the compressor exchanges heat with the low-temperature carbon dioxide gas circulated by the fan in the heat exchanger, so that the low-temperature carbon dioxide gas circulated by the fan becomes high-temperature carbon dioxide gas before entering the adsorption tower, keeping the temperature of the gas entering the adsorption tower and the gas entering the outside stable. By controlling the fan speed and the stable temperature of the gas entering the adsorption tower inlet, the variable temperature section moves forward at a uniform speed, keeping the outlet of the adsorption tower stably discharging low-temperature carbon dioxide gas and the exhaust flow rate stable.

[0051] A schematic diagram illustrating the temperature shift process in the adsorption tower during high-temperature desorption is shown below. Figure 3 As shown, Figure 3 (A) shows the initial stage, the distribution of the high-temperature section, variable-temperature section and low-temperature section in the adsorption tower. As high-temperature carbon dioxide gas enters the adsorption tower, a high-temperature section is formed at the inlet of the adsorption tower. As the high-temperature carbon dioxide moves forward, its temperature gradually decreases, forming a variable-temperature section. The temperature at the rear end of the adsorption tower does not change and remains at a low temperature, which is the low-temperature section. The carbon dioxide desorbed from the high-temperature section and the variable-temperature section is cooled and becomes low-temperature carbon dioxide gas, which is discharged from the outlet of the adsorption tower. Figure 3In section (B), as the amount of high-temperature carbon dioxide gas entering the adsorption tower increases, the temperature inside the adsorption tower gradually rises, and the carbon dioxide gas gradually desorbs. The length of the high-temperature section gradually increases, while the length of the low-temperature section gradually shortens, which is equivalent to the temperature-changing section moving forward.

[0052] For example, the temperature of the high-temperature carbon dioxide gas is 200°C, and the temperature of the low-temperature carbon dioxide gas is 30°C. The relationship between the mass of gas discharged from the adsorption tower and the distance of the temperature-changing section is shown in the first formula:

[0053] ΔM=ΔL*S*ρ*(N 200℃ -N 30℃ );

[0054] Where ΔM is the mass of gas discharged from the adsorption tower; ΔL is the displacement distance of the temperature-changing section; S is the cross-sectional area of ​​the adsorption tower; ρ is the bulk density of the adsorbent module; and N 200℃ and N 30℃ These represent the mass of carbon dioxide gas adsorbed per unit mass of adsorbent at 200℃ and 30℃, respectively.

[0055] Accordingly, when the gas entering the adsorption tower is high-temperature carbon dioxide gas at a temperature of 200℃, and the exhaust temperature of the adsorption tower is 30℃, the exhaust flow rate of the adsorption tower is as shown in the second formula:

[0056] Q = ρ 30℃ *(N 200℃ -N 30℃ )*S*V;

[0057] Where Q is the exhaust flow rate of the adsorption tower, ρ 30℃ The density of the gas at normal pressure and 30°C is N. 200℃ This represents the mass of gas adsorbed per unit mass of adsorbent at 200℃, expressed in N. 30℃ The value represents the mass of gas adsorbed per unit mass of the adsorbent at 30°C, S is the cross-sectional area of ​​the adsorption tower, and V is the velocity of the temperature-changing section.

[0058] In other words, the cross-sectional area of ​​the adsorption tower is constant. As long as the fan speed and the gas temperature entering the adsorption tower are kept stable, the nonlinear temperature-dependent desorption characteristics of the adsorbent do not need to be considered, so that the exhaust flow rate and exhaust temperature can remain stable during the high-temperature desorption process.

[0059] Accordingly, during the low-temperature adsorption process, that is, when the gas entering the adsorption tower is low-temperature carbon dioxide gas, step S2 includes:

[0060] During operation, the outlet of the adsorption tower stably discharges high-temperature carbon dioxide gas. The discharged high-temperature carbon dioxide gas passes sequentially through the fan and the heat exchanger, forming low-temperature carbon dioxide gas, which then re-enters the inlet of the adsorption tower for circulation. The low-temperature carbon dioxide gas entering from the outside exchanges heat with the high-temperature carbon dioxide gas entering the heat exchanger through the fan, forming high-temperature carbon dioxide gas. The high-temperature carbon dioxide gas discharged from the heat exchanger passes through the expander and forms low-temperature carbon dioxide gas, which then enters the inlet of the adsorption tower. By controlling the fan speed, the temperature of the gas discharged from the expander, and the gas entering the inlet of the adsorption tower, the variable temperature section is pushed forward at a uniform speed, ensuring that the adsorption tower stably adsorbs high-temperature carbon dioxide gas and that the gas storage flow rate is stable.

[0061] In other words, when in a low-temperature adsorption state, the adsorption tower is initially at a high temperature (200℃). Low-temperature (30℃) carbon dioxide gas is then introduced into the adsorption tower, lowering the temperature at one end of the inlet to 30℃, forming a low-temperature section. In this low-temperature section, some carbon dioxide gas is adsorbed, while the unadsorbed low-temperature carbon dioxide gas continues to advance, lowering the temperature of the section following the low-temperature section to between 30℃ and 200℃, forming a variable-temperature section. This variable-temperature section again adsorbs some carbon dioxide gas, while the unadsorbed carbon dioxide gas is heated to a high temperature (200℃) and cannot be adsorbed by the adsorption tower. It is discharged through the outlet of the adsorption tower. The discharged gas is circulated by a fan and enters a heat exchanger to exchange heat with external low-temperature carbon dioxide gas, forming low-temperature carbon dioxide gas, which then re-enters the adsorption tower. Simultaneously, the external low-temperature carbon dioxide gas, after heat exchange in the heat exchanger, forms high-temperature carbon dioxide gas, which is then expanded and cooled by an expander, also forming low-temperature carbon dioxide gas that enters the adsorption tower. As more and more low-temperature carbon dioxide gas enters the adsorption tower, the tower continuously adsorbs carbon dioxide gas, causing the variable-temperature section to gradually move forward until adsorption is complete at all locations within the adsorption tower.

[0062] Although the invention has been disclosed above, the scope of protection of this invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this invention, and all such changes and modifications will fall within the scope of protection of this invention.

Claims

1. A method for operating a gas-heat co-storage system, characterized in that, include: Step S1: By controlling the fan speed, high-temperature carbon dioxide gas or low-temperature carbon dioxide gas enters the adsorption tower, forming a high-temperature section, a variable-temperature section, and a low-temperature section. In the initial stage, the initial length of the variable-temperature section is less than or equal to 15% of the total length of the adsorption tower. Step S2: During operation, by controlling the wind speed of the fan and the temperature of the gas entering the inlet of the adsorption tower to keep stable, the variable temperature section moves forward at a constant speed, and the exhaust or storage gas flow rate and exhaust or storage gas temperature at the outlet of the adsorption tower are kept stable. The adsorption tower is equipped with a carbon dioxide adsorbent for adsorbing and desorbing carbon dioxide gas, the fan is used to circulate carbon dioxide gas, and the heat exchanger is used for heat exchange. The adsorption tower has a first pipeline at its outlet, the fan inlet is connected to the adsorption tower outlet through the first pipeline, the fan outlet is connected to the heat exchanger inlet through a second pipeline, the heat exchanger outlet is connected to the adsorption tower inlet through a third pipeline, and the heat exchanger is also provided with a second inlet and a second outlet.

2. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, In step S1, the temperature of the high-temperature carbon dioxide gas is 200°C, and the temperature of the low-temperature carbon dioxide gas is 30°C.

3. The operation method of the gas-heat co-storage system according to claim 2, characterized in that, In step S1, the temperature of the high-temperature section is 200°C, the temperature of the low-temperature section is 30°C, and the temperature of the variable-temperature section is greater than 30°C and less than 200°C.

4. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, In step S2, during operation, by controlling the wind speed of the fan and the temperature of the gas entering the inlet of the adsorption tower to stabilize, the length change of the variable temperature section is less than or equal to 25% of the initial length, so that the variable temperature section moves forward at a uniform speed, and the exhaust flow rate and exhaust temperature of the adsorption tower outlet are kept stable.

5. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, When the gas entering the adsorption tower is high-temperature carbon dioxide gas, step S2 includes: During operation, the outlet of the adsorption tower stably discharges low-temperature carbon dioxide gas. Part of the discharged low-temperature carbon dioxide gas is compressed into high-temperature carbon dioxide gas and then enters the heat exchanger. The other part passes through the fan and the heat exchanger in sequence. The high-temperature carbon dioxide gas formed by the compressor exchanges heat with the low-temperature carbon dioxide gas circulated by the fan in the heat exchanger, so that the low-temperature carbon dioxide gas circulated by the fan becomes high-temperature carbon dioxide gas before entering the adsorption tower, keeping the temperature of the gas entering the adsorption tower and the gas entering the outside stable. By controlling the fan speed and the stable temperature of the gas entering the adsorption tower inlet, the variable temperature section moves forward at a uniform speed, keeping the outlet of the adsorption tower stably discharging low-temperature carbon dioxide gas and the exhaust flow rate stable.

6. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, When the gas entering the adsorption tower is low-temperature carbon dioxide gas, step S2 includes: During operation, the outlet of the adsorption tower stably discharges high-temperature carbon dioxide gas. The discharged high-temperature carbon dioxide gas passes sequentially through the fan and heat exchanger, forming low-temperature carbon dioxide gas, which then re-enters the inlet of the adsorption tower for circulation. The low-temperature carbon dioxide gas entering from the outside exchanges heat with the high-temperature carbon dioxide gas entering the heat exchanger through the fan, forming high-temperature carbon dioxide gas. The high-temperature carbon dioxide gas discharged from the heat exchanger passes through the expander and forms low-temperature carbon dioxide gas, which then enters the inlet of the adsorption tower. By controlling the fan speed, the temperature of the gas discharged from the expander, and the gas entering the inlet of the adsorption tower, the variable temperature section moves forward at a uniform speed, ensuring that the adsorption tower stably adsorbs high-temperature carbon dioxide gas and that the gas storage flow rate is stable.

7. The operation method of the gas-heat co-storage system according to claim 5, characterized in that, When the gas entering the adsorption tower is high-temperature carbon dioxide gas at a temperature of 200°C, in step S2, when the exhaust temperature of the adsorption tower is 30°C, the exhaust flow rate of the adsorption tower is as shown in the second formula: Q=ρ 30℃ *(N 200℃ - N 30℃ ) *S*V; Where Q is the exhaust flow rate of the adsorption tower, ρ 30℃ The density of the gas at normal pressure and 30°C is N. 200℃ This represents the mass of gas adsorbed per unit mass of adsorbent at 200℃, expressed in N. 30℃ The value represents the mass of gas adsorbed per unit mass of the adsorbent at 30°C, S is the cross-sectional area of ​​the adsorption tower, and V is the velocity of the temperature-changing section.

8. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, It also includes a compressor, the air inlet of which is connected to the air outlet of the adsorption tower through a fourth pipeline, the air outlet of which is connected to the second air inlet of the heat exchanger through a fifth pipeline, and the second air outlet of the heat exchanger is connected to the outside through a sixth pipeline.

9. The operation method of the gas-heat co-storage system according to claim 1, characterized in that, It also includes an expander, wherein the second outlet of the heat exchanger is connected to the inlet of the expander via a seventh pipeline, and the outlet of the expander is connected to the inlet of the adsorption tower via an eighth pipeline.

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