Carbon capture system with lean and rich liquid waste heat recovery device

Abstract

The invention provides a carbon capture system with a rich and lean liquid waste heat recovery device, and relates to the technical field of carbon capture systems, the carbon capture system comprises an absorption tower and a regeneration tower, the upper part of the absorption tower is communicated with the bottom end of the regeneration tower through a first pipeline, and the bottom end of the absorption tower is communicated with the upper part of the regeneration tower through a second pipeline; the first pipeline exchanges heat with the second pipeline through a heat exchanger. By additionally arranging the heat pump unit, the link that a cooler is independently arranged on barren liquor is omitted, heat carried by the barren liquor from the bottom of the regeneration tower is utilized, the heat is used for heating a solution at the bottom of the regeneration tower, the requirement of the system for external energy is reduced, and then the energy utilization rate is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon capture systems, and particularly to a carbon capture system with a rich and lean liquid waste heat recovery device. Background Art

[0002] With the rapid development of industrialization and modernization, carbon emissions have become one of the important environmental problems faced globally. Carbon emissions mainly come from the combustion of fossil fuels such as coal, oil, and natural gas. Since carbon dioxide in the atmosphere absorbs long-wave radiation, it will cause the greenhouse effect and lead to global warming.

[0003] Currently, the main separation methods for carbon dioxide are: physical adsorption method, chemical absorption method, and membrane separation method. The captured carbon dioxide can be widely used in industrial utilization fields such as food processing, offshore oil displacement, and chemical product production after compression and purification.

[0004] During the process of treating the rich liquid after absorption in the chemical absorption method used, heat is generated and absorbed during the chemical reaction process. The utilization of heat in the entire chemical absorption method is not sufficient, which may cause waste of energy in the carbon capture system. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a carbon capture system with a rich and lean liquid waste heat recovery device to solve the problem of insufficient energy utilization in the chemical carbon capture process.

[0006] Based on the technical problems existing in the background art, the present invention proposes a carbon capture system with a rich and lean liquid waste heat recovery device, including an absorption tower and a regeneration tower. The upper part of the absorption tower is connected to the bottom end of the regeneration tower through a first pipeline, and the bottom end of the absorption tower is connected to the upper part of the regeneration tower through a second pipeline. Heat exchange is carried out between the first pipeline and the second pipeline through a heat exchanger.

[0007] Preferably, a rich liquid pump is connected to the second pipeline, and a lean liquid pump is connected to the first pipeline.

[0008] Preferably, a heater is provided at the bottom of the regeneration tower.

[0009] Preferably, the heater is connected to a heat pump, and a cycle is formed between the heater and the heat pump through two pipe bodies. The two pipe bodies are respectively connected to an electric heater and a circulation pump.

[0010] Preferably, the heat pump is connected to the second pipeline for heat exchange, and the heat pump is connected between the heat exchanger and the absorption tower.

[0011] Preferably, a raw gas filter is connected below the absorption tower.

[0012] Preferably, the bottom end of the absorption tower inputs the rich liquid that absorbs carbon dioxide above the regeneration tower.

[0013] Preferably, the bottom end of the regeneration tower inputs the lean liquid above the absorption tower.

[0014] Compared with the prior art, a carbon capture system with a rich and lean liquid waste heat recovery device proposed by the present invention adopts the above technical solutions and achieves the following technical effects:

[0015] By adding a heat pump unit, the present invention eliminates the link of separately setting a cooler for the lean liquid, increases the utilization of the heat carried by the lean liquid coming out from the bottom of the regeneration tower, uses it to heat the solution at the bottom of the regeneration tower, reduces the need for external energy of the system, and thus improves the energy utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the system structure diagram of the present invention.

[0017] In the figure: 102, absorption tower; 105, regeneration tower; 112, first pipeline; 113, second pipeline; 104, heat exchanger; 107, lean liquid pump; 106, heater; 108, heat pump; 111, pipe body; 110, electric heater; 109, circulation pump; 101, raw gas filter. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In the present invention, unless otherwise clearly defined and limited, terms such as "installed", "connected", "connected to", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection or communication with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the connection inside two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0019] In the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature is at a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature is at a lower horizontal height than the second feature.

[0020] Embodiment

[0021] Please refer to Figure 1, the present invention provides a carbon capture system with a rich and lean liquid waste heat recovery device, including an absorption tower 102 and a regeneration tower 105. The upper part of the absorption tower 102 is connected to the bottom end of the regeneration tower 105 through a first pipeline 112, and the bottom end of the absorption tower 102 is connected to the upper part of the regeneration tower 105 through a second pipeline 113. Heat exchange is carried out between the first pipeline 112 and the second pipeline 113 through a heat exchanger 104; in this application, there is a heat conversion between the rich liquid and the lean liquid between the absorption tower 102 and the regeneration tower 105. When the absorption tower 102 is used to receive the raw gas, it will be transported to the top of the regeneration tower 105 through the second pipeline 113. The raw gas will fuse with the acid gas in the absorption tower 102 to form rich liquid. At this time, the state of the rich liquid is 46 °C and 250 kPa. When the rich liquid enters the regeneration tower 105, the temperature of the rich liquid in the second pipeline 113 will be heated to 85 °C, and its pressure will rise to 450 kPa. After passing through the reaction in the regeneration tower 105, lean liquid is formed. The temperature of the lean liquid is 80 °C, and it is transported to the absorption tower 102 through the first pipeline 112. The lean liquid will drop from 80 °C to 40 °C in the first pipeline 112 and be transported to the absorption tower 102. The second pipeline 113 has a heating effect, and the first pipeline 112 has a cooling effect. Heat exchange can be carried out between the two pipelines through the heat exchanger 104 to reduce energy loss.

[0022] In a specific embodiment, refer to Figure 1 , a rich liquid pump is connected to the second pipeline 113, and a lean liquid pump 107 is connected to the first pipeline 112; in this solution, the liquid flow in the second pipeline 113 is controlled by the rich liquid pump. One end of the second pipeline 113 is connected to the lower end of the absorption tower 102, and the rich liquid at the lower end of the absorption tower 102 can be transported to the upper part of the regeneration tower 105. The rich liquid pump is located between the heat exchanger 104 and the absorption tower 102; the liquid flow in the first pipeline 112 is controlled by the lean liquid pump 107. One end of the first pipeline 112 is connected to the lower end of the regeneration tower 105, and the lean liquid at the lower end of the regeneration tower 105 can be transported to the upper part of the absorption tower 102. The lean liquid pump 107 is located between the heat exchanger 104 and the regeneration tower 105.

[0023] In a specific embodiment, refer to Figure 1 , a heater 106 is provided at the bottom of the regeneration tower 105; the heater 106 provided at the bottom of the regeneration tower 105 in this solution is used to heat the liquid inside the regeneration tower 105, which can improve the heating rate of the solution in the regeneration tower 105 and the reaction rate of the regeneration tower 105.

[0024] In a specific embodiment, refer to Figure 1, a heater 106 is connected to a heat pump 108. A circulation is formed between the heater 106 and the heat pump 108 through two pipe bodies 111. The two pipe bodies 111 are respectively connected to an electric heater 110 for the 106 and a circulation pump 109. In this solution, the electric heater 110 connected to the heater 106 can be used for the initial heating of the front section of the heater 106, enabling the heater 106 to have a running buffer time. At the same time, the electric heater 110 can also provide a heating effect for the heat pump 108 and can extract and collect heat from the first pipeline 112. The heat pump 108 in this application is located between the collection tower and the heat exchanger 104 and can further collect the heat after passing through the heat exchanger 104, reducing heat waste. The heat-conducting oil at about 120 °C after heat exchange in the heater 106 enters the heat pump 108 through the circulation pump 109 for preliminary heat exchange and is heated to about 131 °C, and then is heated to 180 °C by the electric heater 110 and then returns to the heater 106 to heat the amine liquid.

[0025] In a specific embodiment, refer to Figure 1 , the heat pump 108 is connected to the second pipeline 113 for heat exchange, and the heat pump 108 is connected between the heat exchanger 104 and the absorption tower 102. In this solution, the heat pump 108 can continue to absorb the heat after the heat exchanger 104 and can use the heat on the heater 106 to relieve the buffer heating time required when the heater 106 starts.

[0026] In a specific embodiment, refer to Figure 1 , a raw gas filter 101 is connected below the absorption tower 102. In this solution, the raw gas filter 101 device is used to filter impurities in the raw gas to avoid blockage or damage in the absorption tower 102 caused by impurities.

[0027] In a specific embodiment, refer to Figure 1 , the bottom end of the absorption tower 102 inputs the rich liquid absorbing carbon dioxide above the regeneration tower 105, and the bottom end of the regeneration tower 105 inputs the lean liquid above the absorption tower 102.

[0028] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A carbon capture system with a lean and rich liquid waste heat recovery device, characterized in that: The invention comprises an absorption tower (102) and a regeneration tower (105), wherein the upper end of the absorption tower (102) is connected to the lower end of the regeneration tower (105) via a first pipe (112), and the lower end of the absorption tower (102) is connected to the upper end of the regeneration tower (105) via a second pipe (113), and heat is exchanged between the first pipe (112) and the second pipe (113) via a heat exchanger (104).

2. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 1, characterized in that: The second pipeline (113) is connected to a rich liquid pump (103), and the first pipeline (112) is connected to a lean liquid pump (107).

3. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 1, characterized in that: A heater (106) is provided at the bottom of the regeneration tower (105).

4. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 3, characterized in that: The heater (106) is connected to a heat pump (108), and a circulation is formed between the heater (106) and the heat pump (108) via two pipe bodies (111), and the two pipe bodies (111) are respectively connected to an electric heater (110) and a circulation pump (109).

5. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 4, characterized in that: The heat pump (108) is connected to the second pipeline (113) for heat exchange, and the heat pump is connected between the heat exchanger (104) and the absorption tower (102).

6. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 1, characterized in that: The lower part of the absorption tower (102) is connected to a raw gas filter (101).

7. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 1, characterized in that: The bottom end of the absorption tower (102) inputs rich liquid for absorbing carbon dioxide into the top of the regeneration tower (105).

8. The carbon capture system with a lean and rich liquid waste heat recovery device according to claim 1, characterized in that: The bottom end of the regeneration tower (105) inputs the lean liquid to the top of the absorption tower (102).

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