Carbon dioxide trapping system applied to thermal power generating unit

Abstract

The invention provides a carbon dioxide trapping system applied to a thermal power generating unit. The carbon dioxide trapping system comprises a membrane separation unit, a carbonation reaction unit, a cyclone separator, a carbon dioxide release unit, a first pipeline and a heat exchanger, the membrane separation unit is provided with an inlet, a first outlet and a second outlet, the inlet of the membrane separation unit is connected with a flue gas pipeline, and the first outlet of the membrane separation unit is connected with the inlet of the carbonation reaction unit; an outlet of the carbonation reaction unit is connected with an inlet of the cyclone separator; a first outlet of the cyclone separator is connected with an inlet of the carbon dioxide release unit; and a second outlet of the cyclone separator is connected with the heat exchanger through the first pipeline. The method has the technical effects that the economical efficiency and the effectiveness of carbon capture can be improved, and the comprehensive utilization efficiency of energy can be improved, so that a technical support is provided for realizing a sustainable green development target.

Description

Technical Field

[0001] The invention belongs to the technical field of boiler environmental protection and atmospheric environmental protection, and in particular relates to a carbon dioxide capture system applied to a thermal power unit. Background Art

[0002] In order to promote the construction of ecological civilization, many thermal power plants are currently actively preparing to build carbon capture devices. The main goal of carbon capture devices is to effectively reduce carbon emissions from coal-fired power units, thereby helping to achieve green transformation in the coal-fired power sector. However, existing carbon capture devices on the market generally have problems such as high energy consumption and low carbon dioxide absorption, which makes it difficult for units that build carbon capture devices to obtain economic benefits, thus hindering the promotion and industrial application of carbon capture technology.

[0003] In addition, traditional thermal power units have large heat dissipation during operation, and they also need to undertake the task of power peak regulation, resulting in serious power waste; in the field of new energy, wind power, photovoltaic power generation methods have the problem of "abandoning wind and light" due to instability, which further aggravates energy waste. These problems not only reduce the overall energy utilization efficiency, but also limit the utilization rate of clean energy. Therefore, finding efficient energy storage technology and improving the level of energy storage and reuse has become one of the key ways to improve energy utilization efficiency and achieve energy conservation and emission reduction.

[0004] Therefore, there is an urgent need for a carbon dioxide capture system applied to thermal power units to combine low-energy carbon dioxide capture technology with high-efficiency energy and heat storage technology, thereby improving the economy and effectiveness of carbon capture. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art and provide a new technical solution for a carbon dioxide capture system applied to a thermal power unit.

[0006] According to a first aspect of the present invention, there is provided a carbon dioxide capture system for a thermal power unit, comprising a membrane separation unit, a carbonation reaction unit, a cyclone separator, a carbon dioxide release unit, a first pipeline and a heat exchanger;

[0007] The membrane separation unit has an inlet, a first outlet and a second outlet, the inlet of the membrane separation unit is connected to the flue gas duct, and the first outlet of the membrane separation unit is connected to the inlet of the carbonation reaction unit;

[0008] The outlet of the carbonation reaction unit is connected to the inlet of the cyclone separator; the first outlet of the cyclone separator is connected to the inlet of the carbon dioxide release unit;

[0009] The second outlet of the cyclone separator is connected to the heat exchanger through the first pipeline;

[0010] The flue gas is separated in the membrane separation unit to obtain nitrogen and a mixed gas, the nitrogen is output from the second outlet of the membrane separation unit, and the mixed gas enters the carbonation reaction unit through the first outlet of the membrane separation unit for a chemical reaction, wherein the carbon dioxide in the mixed gas reacts with the calcium oxide in the carbonation reaction unit to generate solid calcium carbonate; the gas-solid mixture after the reaction is subjected to gas-solid separation in the cyclone separator to obtain purified gas and solid calcium carbonate, the purified gas is output from the second outlet of the cyclone separator and exchanges heat with the liquid in the heat exchanger, and the solid calcium carbonate enters the carbon dioxide release unit from the first outlet of the cyclone separator for heating and calcination to form carbon dioxide and calcium oxide.

[0011] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a gas storage tank;

[0012] The inlet of the gas storage tank is connected to the first outlet of the membrane separation unit, the outlet of the gas storage tank is connected to the inlet of the carbonation reaction unit, and the gas storage tank is used to store the mixed gas.

[0013] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a calcium oxide storage tank and a second pipeline;

[0014] One end of the second pipeline is connected to the first outlet of the carbon dioxide release unit, and the other end is connected to the carbonation reaction unit. The calcium oxide storage tank is arranged in the second pipeline for storing calcium oxide;

[0015] The calcium oxide in the carbon dioxide release unit can be circulated into the carbonation reaction unit through the second pipeline.

[0016] Optionally, in the mixed gas, the concentration of carbon dioxide is 50%, the concentration of oxygen is 10%, and the concentration of nitrogen is 40%.

[0017] Optionally, the inlet of the membrane separation unit is arranged at the top of the membrane separation unit; the first outlet and the second outlet of the membrane separation unit are both arranged at the bottom of the membrane separation unit.

[0018] Optionally, the inlet of the carbonation reaction unit is arranged at the bottom of the carbonation reaction unit; and the outlet of the carbonation reaction unit is arranged at the top of the carbonation reaction unit.

[0019] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a third pipeline;

[0020] One end of the third pipeline is connected to the second outlet of the carbon dioxide release unit.

[0021] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a calcium carbonate storage tank;

[0022] The inlet of the calcium carbonate storage tank is connected to the first outlet of the cyclone separator, and the outlet of the calcium carbonate storage tank is connected to the inlet of the carbon dioxide release unit.

[0023] Optionally, the first outlet of the carbon dioxide release unit is located at the bottom of the carbon dioxide release unit; and the second outlet of the carbon dioxide release unit is located at the top of the carbon dioxide release unit.

[0024] Optionally, in the flue gas, the concentration of carbon dioxide is 13%, the concentration of oxygen is 6%, and the concentration of nitrogen is 81%.

[0025] A technical effect of the present invention is:

[0026] In the embodiment of the present application, the carbon dioxide in the flue gas can be enriched by the membrane separation unit, so that the carbonation reaction temperature of the carbonation reaction unit is increased under the same carbon capture efficiency condition, and the heat generated by part of the carbonation reaction process is used to exchange heat with the liquid in the heat exchanger, thereby improving the energy utilization efficiency and quality. In addition, the energy source of the carbon dioxide capture system applied to the thermal power unit is the waste heat of the thermal power plant and the electricity of the abandoned wind and solar power of new energy, realizing the efficient utilization of power resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural schematic diagram of a carbon dioxide capture system applied to a thermal power unit according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the change of CO2 partial pressure in the outlet gas of the carbonation reaction unit according to another embodiment of the present invention with the carbonation temperature.

[0029] In the figure: 1. membrane separation unit; 2. carbonation reaction unit; 3. cyclone separator;

[0030] 4. Carbon dioxide release unit; 5. First pipeline; 6. Heat exchanger; 7. Gas storage tank;

[0031] 8. Calcium oxide storage tank; 9. Second pipeline; 10. Third pipeline; 11. Calcium carbonate storage tank. DETAILED DESCRIPTION

[0032] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0033] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0034] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0036] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0037] According to a first aspect of the present invention, see Figure 1 , provides a carbon dioxide capture system for thermal power units, which can combine low-energy CO2 capture technology with high-efficiency energy and heat storage technology.

[0038] Specifically, the carbon dioxide capture system applied to thermal power units integrates the membrane separation unit 1 and the high-temperature calcium-based adsorbent in the carbonation reaction unit 2 to adsorb CO2, so that the high-temperature calcium-based adsorbent can not only capture CO2, but also store excess energy and release it when needed, thereby improving the comprehensive utilization efficiency of energy.

[0039] Specifically, the carbon dioxide capture system applied to a thermal power unit comprises a membrane separation unit 1, a carbonation reaction unit 2, a cyclone separator 3, a carbon dioxide release unit 4, a first pipeline 5 and a heat exchanger 6;

[0040] The membrane separation unit 1 has an inlet, a first outlet and a second outlet, the inlet of the membrane separation unit 1 is connected to the flue gas duct, and the first outlet of the membrane separation unit 1 is connected to the inlet of the carbonation reaction unit 2;

[0041] The outlet of the carbonation reaction unit 2 is connected to the inlet of the cyclone separator 3; the first outlet of the cyclone separator 3 is connected to the inlet of the carbon dioxide release unit 4;

[0042] The second outlet of the cyclone separator 3 is connected to the heat exchanger 6 through the first pipeline 5;

[0043] The flue gas is separated in the membrane separation unit 1 to obtain nitrogen and mixed gas, the nitrogen is output from the second outlet of the membrane separation unit 1, and the mixed gas enters the carbonation reaction unit 2 through the first outlet of the membrane separation unit 1 for chemical reaction, wherein the carbon dioxide in the mixed gas reacts with the calcium oxide in the carbonation reaction unit 2 to generate solid calcium carbonate; the gas-solid mixture after the reaction is subjected to gas-solid separation in the cyclone separator 3 to obtain purified gas and solid calcium carbonate, the purified gas is output from the second outlet of the cyclone separator 3 and heat-exchanged with the liquid in the heat exchanger 6, and the solid calcium carbonate enters the carbon dioxide release unit 4 from the first outlet of the cyclone separator 3 for heating and calcination to form carbon dioxide and calcium oxide. The heating and calcination process uses waste heat from thermal power plants or abandoned wind and solar power as heat sources to improve resource utilization efficiency.

[0044] It should be emphasized that the carbon dioxide concentration at the inlet of the carbonation reaction unit 2 is significantly increased by treating the flue gas of the thermal power plant through the membrane separation unit 1 .

[0045] For example, the membrane separation unit 1 is used to treat the flue gas of a thermal power plant, and the concentration of carbon dioxide in the flue gas is increased from 13% to 50%. The membrane separation unit 1 has the characteristics of high selectivity and low energy consumption, and can efficiently separate carbon dioxide.

[0046] Further, calcium oxide is filled in the carbonation reaction unit 2, and the high concentration carbon dioxide gas after concentration is reacted with the calcium oxide (CaO) in the carbonation reaction unit 2 to generate calcium carbonate (CaCO ). Wherein, carbonation reaction can release a large amount of heat, and this part of heat can be used for other techniques or heating requirements of power plant. Then, the waste heat of thermal power plant or the electric power of abandoning wind and light are adopted as heat source, to the CaCO generated, and high concentration of carbon dioxide and calcium oxide are discharged. The carbon dioxide produced can be used for other industrial purposes, and calcium oxide can enter the carbonation reaction unit 2 and continue to carry out carbonation reaction with high concentration of carbon dioxide, and is recycled.

[0047] In the embodiment of the present application, the carbon dioxide in the flue gas can be enriched by the membrane separation unit 1, so that the carbonation reaction temperature of the carbonation reaction unit 2 is increased under the same carbon capture efficiency condition, and the heat generated by part of the carbonation reaction process is used to exchange heat with the liquid in the heat exchanger 6, thereby improving the energy utilization efficiency and quality. In addition, the energy source of the carbon dioxide capture system applied to the thermal power unit is the waste heat of the thermal power plant and the electricity of the abandoned wind and solar power of new energy, realizing the efficient utilization of power resources.

[0048] Therefore, the carbon dioxide capture system applied to thermal power units can not only improve the economy and effectiveness of carbon capture, but also improve the comprehensive utilization efficiency of energy, thereby providing technical support for achieving sustainable green development goals.

[0049] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a gas storage tank 7;

[0050] The inlet of the gas storage tank 7 is connected to the first outlet of the membrane separation unit 1 , and the outlet of the gas storage tank 7 is connected to the inlet of the carbonation reaction unit 2 . The gas storage tank 7 is used to store the mixed gas.

[0051] In the above embodiment, the gas storage tank 7 can store the mixed gas, so as to facilitate the control of the carbonation reaction and simplify the operation.

[0052] Optionally, the carbon dioxide capture system applied to a thermal power unit further comprises a calcium oxide storage tank 8 and a second pipeline 9;

[0053] One end of the second pipeline 9 is connected to the first outlet of the carbon dioxide release unit 4, and the other end is connected to the carbonation reaction unit 2. The calcium oxide storage tank 8 is arranged on the second pipeline 9 for storing calcium oxide;

[0054] The calcium oxide in the carbon dioxide release unit 4 can be circulated into the carbonation reaction unit 2 through the second pipeline 9 .

[0055] In the above embodiment, the calcium oxide storage tank 8 can store calcium oxide, so as to facilitate the circulation of calcium oxide into the carbonation reaction unit 2 and control the carbonation reaction, and the operation is simple.

[0056] Optionally, in the mixed gas, the concentration of carbon dioxide is 50%, the concentration of oxygen is 10%, and the concentration of nitrogen is 40%. This enables the separation process of the membrane separation unit 1 to achieve the enrichment of carbon dioxide in the flue gas, thereby realizing the energy utilization of the carbonation reaction.

[0057] Optionally, the inlet of the membrane separation unit 1 is arranged at the top of the membrane separation unit 1; the first outlet and the second outlet of the membrane separation unit 1 are both arranged at the bottom of the membrane separation unit 1. This makes the structural design of the membrane separation unit 1 more reasonable and facilitates the separation of flue gas.

[0058] Optionally, the inlet of the carbonation reaction unit 2 is arranged at the bottom of the carbonation reaction unit 2; and the outlet of the carbonation reaction unit 2 is arranged at the top of the carbonation reaction unit 2. This makes the structural design of the carbonation reaction unit 2 more reasonable and facilitates the carbonation reaction.

[0059] Optionally, the carbon dioxide capture system applied to a thermal power unit further includes a third pipeline 10;

[0060] One end of the third pipe 10 is connected to the second outlet of the carbon dioxide release unit 4 .

[0061] In the above embodiment, carbon dioxide can be stably output through the third pipeline 10, thereby achieving the consumption of carbon dioxide.

[0062] Optionally, the carbon dioxide capture system applied to a thermal power unit further includes a calcium carbonate storage tank 11;

[0063] The inlet of the calcium carbonate storage tank 11 is connected to the first outlet of the cyclone separator 3 , and the outlet of the calcium carbonate storage tank 11 is connected to the inlet of the carbon dioxide release unit 4 .

[0064] In the above embodiment, the calcium carbonate storage tank 11 can store calcium carbonate, thereby facilitating the control of the calcination of calcium carbonate.

[0065] Optionally, the first outlet of the carbon dioxide release unit 4 is located at the bottom of the carbon dioxide release unit 4, and the second outlet of the carbon dioxide release unit 4 is located at the top of the carbon dioxide release unit 4. The structure of the carbon dioxide release unit 4 is reasonably designed, so as to facilitate the output of the reacted carbon dioxide and calcium oxide.

[0066] Optionally, in the flue gas, the concentration of carbon dioxide is 13%, the concentration of oxygen is 6%, and the concentration of nitrogen is 81%.

[0067] In a specific embodiment, the carbon dioxide capture system applied to a thermal power unit has the following working process:

[0068] First, the flue gas from the thermal power plant after dust removal and dehydration (for example, the concentration of CO2 is 13%, the concentration of O2 is 6%, and the concentration of N2 is 81%) enters the membrane separation unit 1 from the inlet of the membrane separation unit 1, and is separated by the membrane separation unit 1 to form two gases, namely, CO2-enriched gas (i.e., mixed gas, in which the concentration of CO2 is 50%, the concentration of O2 is 10%, and the concentration of N2 is 40%) and N2-enriched gas (i.e., nitrogen).

[0069] Secondly, the CO2-enriched gas enters the gas storage tank 7 for storage. The CO2-enriched gas in the gas storage tank 7 is released from the gas storage tank 7 when needed, enters the carbonation reaction unit 2 to react with CaO to generate purified gas and CaCO3, and the gas-solid mixture after the reaction is discharged from the top of the carbonation reaction unit 2, and after the gas-solid separation in the cyclone separator 3, the purified gas is discharged from the top of the cyclone separator 3 to form purified gas, and the purified gas carries heat in the heat exchanger 6 to exchange heat with the liquid to be exchanged.

[0070] Finally, CaCO3 is discharged from the bottom of the cyclone separator 3 and stored in the calcium carbonate storage tank 11. The CaCO3 in the calcium carbonate storage tank 11 enters the carbon dioxide release unit 4 for heating and calcination when needed, the generated CO2 is discharged from the top of the carbon dioxide release unit 4, and the generated CaO is discharged from the bottom of the carbon dioxide release unit 4 and stored in the calcium oxide storage tank 8. The CaO in the calcium oxide storage tank 8 is transported to the carbonation reaction unit 2 for reaction when needed to achieve the recycling of CaO.

[0071] It should be noted that the working principle of the carbon dioxide capture system applied to thermal power units is as follows:

[0072] (1) Energy storage - CaCO3 calcination - CO2 regeneration stage: The gas separation in the membrane separation unit 1 requires driving force to be realized. The driving force of the membrane separation unit 1 comes from the front compressor, and the carbon dioxide release unit 4 also requires additional energy to heat and decompose the CaCO3 inside it. Therefore, when the thermal power plant needs to peak load reduction or there is excess wind and solar power abandonment from new energy sources, the front compressor of the membrane separation unit 1 and the heating equipment of the carbon dioxide release unit 4 are started to consume the excess electricity. The compressor drives the flue gas into the membrane separation unit 1 to separate and process the flue gas, and the CO2-enriched gas is stored in the gas storage tank 7, and the CaO formed after the CaCO3 is calcined is stored in the calcium oxide storage tank 8.

[0073] (2) Energy release - CaO carbonation - CO2 capture stage: When the thermal power plant needs to peak load regulation, the high-concentration CO2 in the gas storage tank 7 is released, and the CaO in the calcium oxide storage tank 8 is released. The two react in the carbonation reaction unit 2. The heat generated after the reaction is taken away by the purified gas (that is, ) and is used to increase the boiler feed water temperature and quickly increase the boiler load.

[0074] See also Figure 2 , the experimental data and effect verification are as follows:

[0075] When the membrane separation unit 1 is not used, the concentration of CO2 in the mixed gas at the inlet of the carbonation reaction unit 2 is 13%. If the carbon capture efficiency of the carbonation reaction unit 2 is 90%, the concentration of CO2 at the outlet of the carbonation reaction unit 2 is about 1.3%.

[0076] After using the membrane separation unit 1, the concentration of CO2 in the mixed gas at the inlet of the carbonation reaction unit 2 is 50%. Under the same carbon capture efficiency (90%), the concentration of CO2 at the outlet of the carbonation reaction unit 2 is 9%. Figure 2 It can be seen that after adding the membrane separation unit 1, the carbonation reaction temperature can be increased from 650°C to 750°C, thereby significantly improving the thermal energy utilization grade.

[0077] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A carbon dioxide capture system applied to a thermal power unit, characterized in that: It includes a membrane separation unit, a carbonation reaction unit, a cyclone separator, a carbon dioxide release unit, a first pipeline and a heat exchanger; The membrane separation unit has an inlet, a first outlet and a second outlet, the inlet of the membrane separation unit is connected to the flue gas duct, and the first outlet of the membrane separation unit is connected to the inlet of the carbonation reaction unit; The outlet of the carbonation reaction unit is connected to the inlet of the cyclone separator; the first outlet of the cyclone separator is connected to the inlet of the carbon dioxide release unit; The second outlet of the cyclone separator is connected to the heat exchanger through the first pipeline; The flue gas is separated in the membrane separation unit to obtain nitrogen and a mixed gas, the nitrogen is output from the second outlet of the membrane separation unit, and the mixed gas enters the carbonation reaction unit through the first outlet of the membrane separation unit for a chemical reaction, wherein the carbon dioxide in the mixed gas reacts with the calcium oxide in the carbonation reaction unit to generate solid calcium carbonate; the gas-solid mixture after the reaction is subjected to gas-solid separation in the cyclone separator to obtain purified gas and solid calcium carbonate, the purified gas is output from the second outlet of the cyclone separator and exchanges heat with the liquid in the heat exchanger, and the solid calcium carbonate enters the carbon dioxide release unit from the first outlet of the cyclone separator for heating and calcination to form carbon dioxide and calcium oxide.

2. The carbon dioxide capture system applied to a thermal power unit according to claim 1, characterized in that: Also included are gas storage tanks; The inlet of the gas storage tank is connected to the first outlet of the membrane separation unit, the outlet of the gas storage tank is connected to the inlet of the carbonation reaction unit, and the gas storage tank is used to store the mixed gas.

3. The carbon dioxide capture system applied to a thermal power unit according to claim 2, characterized in that: Also included is a calcium oxide storage tank and a second pipeline; One end of the second pipeline is connected to the first outlet of the carbon dioxide release unit, and the other end is connected to the carbonation reaction unit. The calcium oxide storage tank is arranged in the second pipeline for storing calcium oxide; The calcium oxide in the carbon dioxide release unit can be circulated into the carbonation reaction unit through the second pipeline.

4. The carbon dioxide capture system applied to a thermal power unit according to claim 3, characterized in that: In the mixed gas, the concentration of carbon dioxide is 50%, the concentration of oxygen is 10%, and the concentration of nitrogen is 40%.

5. The carbon dioxide capture system applied to a thermal power unit according to claim 4, characterized in that: The inlet of the membrane separation unit is arranged at the top of the membrane separation unit; the first outlet and the second outlet of the membrane separation unit are both arranged at the bottom of the membrane separation unit.

6. The carbon dioxide capture system applied to a thermal power unit according to claim 5, characterized in that: The inlet of the carbonation reaction unit is arranged at the bottom of the carbonation reaction unit; and the outlet of the carbonation reaction unit is arranged at the top of the carbonation reaction unit.

7. The carbon dioxide capture system applied to a thermal power unit according to claim 6, characterized in that: Also included is a third pipeline; One end of the third pipeline is connected to the second outlet of the carbon dioxide release unit.

8. The carbon dioxide capture system applied to a thermal power unit according to claim 7, characterized in that: Also included are calcium carbonate storage tanks; The inlet of the calcium carbonate storage tank is connected to the first outlet of the cyclone separator, and the outlet of the calcium carbonate storage tank is connected to the inlet of the carbon dioxide release unit.

9. The carbon dioxide capture system applied to a thermal power unit according to claim 8, characterized in that: The first outlet of the carbon dioxide release unit is located at the bottom of the carbon dioxide release unit; the second outlet of the carbon dioxide release unit is located at the top of the carbon dioxide release unit.

10. The carbon dioxide capture system applied to a thermal power unit according to claim 9, characterized in that: In the flue gas, the concentration of carbon dioxide is 13%, the concentration of oxygen is 6%, and the concentration of nitrogen is 81%.

Images