Flue gas carbon dioxide trapping system and method with low amine emission

Abstract

The invention provides a low-amine-emission flue gas carbon dioxide capture system and method.The system comprises an absorption tower, one side of the absorption tower is communicated with a storage tank, the storage tank is sequentially connected with a washing pump and a cooler, the other side of the absorption tower is provided with a rich and lean liquid heat exchanger, and one side of the rich and lean liquid heat exchanger is provided with a regeneration tower; a steam reboiler is arranged on one side of the regeneration tower; one end of the steam reboiler is communicated with a circulating pump, the circulating pump is communicated with a regeneration tower through a pipeline, and the regeneration tower is communicated with a rich and lean liquid heat exchanger; the absorption tower is communicated with a rich liquid pump, the rich liquid pump is communicated with the lean and rich liquid heat exchanger, and the steam reboiler is communicated with the regeneration tower through a pipeline; the regeneration tower is communicated with a delivery pump, the delivery pump is communicated with carbon dioxide gas, the carbon dioxide gas is introduced into the top of the regeneration tower, the regeneration tower is connected with a pressure pump, and the other side of the pressure pump is communicated with the absorption tower through a storage tank. The system has the advantages of solving the problems of over-high amine emission, high energy consumption, complex process and the like in a traditional flue gas CO2 trapping system.

Description

Technical Field

[0001] The present invention belongs to the technical field of low amine emission, and in particular relates to a flue gas carbon dioxide capture system and method with low amine emission. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] CO2 capture technology is a new energy technology that uses adsorption, membrane separation, catalytic hydrogenation and oxidation to capture and separate carbon dioxide (CO2) in the atmosphere from other gas mixtures. It helps to reduce the concentration of carbon dioxide in the atmosphere, thereby effectively mitigating global warming and the impact of global warming on our lives and the environment. CO2 capture technology can capture CO2 in different ways.

[0004] C02 capture technology can capture CO2 in different ways. For example, adsorption is a commonly used CO2 capture technology. When using this technology, CO2 in the air reacts with the adsorbent to separate CO2 from other gaseous substances. In addition, membrane technology can also be used to capture CO2. Through membrane isolation technology, C02 and other gaseous substances are separated on the membrane. Catalytic hydrogenation and oxidation technology can also be used to capture CO2 from the atmosphere.

[0005] The existing patent, publication number CN114788997A, discloses a chemical absorption flue gas CO2 capture system, including an absorption tower, a desorption reactor, and a bipolar membrane electrodialysis device. Flue gas enters the absorption tower and reacts with alkaline solution to generate decarbonization products, thereby absorbing carbon dioxide. The desorption reactor is filled with a strong acid solution. The decarbonization products enter the desorption reactor and react with the strong acid to generate carbon dioxide and a feed liquid. The carbon dioxide enters the carbon dioxide recovery system. The feed liquid enters the bipolar membrane electrodialysis device to generate acid and alkaline solution, completing the regeneration of the absorbent. The decarbonization products react with the strong acid in the desorption reactor to remove the carbonate ions in the decarbonization products, and the feed liquid is regenerated in the bipolar membrane electrodialysis device to generate strong acid and alkaline solution. No bubbles are generated during the absorbent regeneration process, thereby ensuring the conductivity of the bipolar membrane electrodialysis device, significantly improving the efficiency of the bipolar membrane electrodialysis device, and reducing system energy consumption.

[0006] In existing flue gas CO2 capture systems, amine solutions are widely used to absorb and capture CO2 in flue gas. However, traditional systems often have the problem of excessive amine emissions during operation. Amine emissions not only cause environmental pollution, but also increase the cost of system operation. This is mainly because during the flue gas treatment process, amine solutions are easily discharged along with the flue gas. Especially during the humidification and scrubbing stages of the flue gas, amine substances in small particles and aerosols are difficult to effectively remove.

[0007] However, in actual application, it is impossible to solve the problems of excessive amine emissions, high energy consumption and complex process in traditional flue gas CO2 capture systems. The system has high energy consumption and complex process. Summary of the Invention

[0008] In order to solve the above problems, the present invention proposes a flue gas carbon dioxide capture system and method with low amine emission. The present invention has the advantages of solving the problems of excessive amine emission, high energy consumption and complex process in traditional flue gas CO2 capture systems.

[0009] According to some embodiments, the present invention adopts the following technical solutions:

[0010] A low-amine emission flue gas carbon dioxide capture system comprises an absorption tower, one side of the absorption tower is connected to a storage tank, the storage tank is sequentially connected to a water wash pump and a cooler, the other side of the absorption tower is provided with a lean-rich liquid heat exchanger, one side of the lean-rich liquid heat exchanger is provided with a regeneration tower, and one side of the regeneration tower is provided with a steam reboiler;

[0011] One end of the steam reboiler is connected to a circulation pump, which is connected to the regeneration tower through a pipeline, and the regeneration tower is connected to the lean-rich liquid heat exchanger;

[0012] One side of the absorption tower is connected to a rich liquid pump, and the rich liquid pump is connected to a lean and rich liquid heat exchanger, and a steam reboiler is connected to a regeneration tower through a pipeline;

[0013] The regeneration tower is connected to a delivery pump, which is connected to carbon dioxide gas. The carbon dioxide gas is introduced into the top of the regeneration tower. The regeneration tower is also connected to a pressure pump, and the other side of the pressure pump is connected to the absorption tower through a storage tank.

[0014] As an optional embodiment, a pressure sensor is provided inside the storage tank, and the central processing unit is bidirectionally connected to the pressure sensor. The central processing unit is connected to the transmission pump, pressure pump, water washing pump, cooler, fan, circulation pump, rich liquid pump, lean-rich liquid heat exchanger and lean liquid pump, and the central processing unit is connected to a data comparison module, the data comparison module is connected to a data storage module, the output end of the central processing unit is electrically connected to a temperature sensor, and the temperature sensor is connected to a steam reboiler.

[0015] As an optional embodiment, the water inlet of the water washing pump is connected to the water inlet of the storage tank through a pipe, the water outlet of the water washing pump is connected to the water inlet of the cooler through a pipe, and the water outlet of the cooler is connected to one side of the absorption tower through a pipe.

[0016] As an optional embodiment, one side of the absorption tower is connected to a transmission pump, and one end of the transmission pump is connected to one side of the lean-rich liquid heat exchanger.

[0017] As an optional embodiment, a fan is connected to the lower end of the absorption tower, and the air outlet of the fan is connected to the absorption tower through a pipeline.

[0018] As an optional embodiment, a cold rich liquid outlet is provided on one side of the absorption tower, and the cold rich liquid outlet is connected to the liquid inlet of the rich liquid pump.

[0019] As an optional embodiment, the connection between the pressure pump and the absorption tower is a humidification section, which uses regenerated gas to heat the flue gas exhaust washing water after the absorption tower to humidify the flue gas. By heating the washing water, small particles and aerosols in the flue gas grow rapidly.

[0020] As an optional implementation, the circulating pump is connected to a steam reboiler, and circulating cooling water is used to cool the flue gas washing water to generate a large amount of condensed water.

[0021] As an optional embodiment, the absorption tower is connected to a wire mesh demister, which is used to treat the flue gas and remove aerosols therein.

[0022] As an optional embodiment, the lean and rich liquid heat exchanger is connected to a lean liquid pump, which is respectively connected to the regeneration tower and the steam reboiler. The rich liquid pump and the lean liquid pump are used for water balance control. The flue gas condensate generated by the steam reboiler is added to the regeneration tower to maintain water balance.

[0023] The working method based on the above system includes the following steps:

[0024] The aerosol growth section at the upper end of the absorption tower is washed by water from the water washing pump and cooler and then returned to the absorption tower;

[0025] The cold rich liquid of the absorption tower flows out from the cold rich liquid outlet and is transferred to the lean rich liquid heat exchanger through the rich liquid pump. The cold lean liquid after heat exchange flows back to the absorption tower;

[0026] The regeneration tower is connected to the lean-rich liquid heat exchanger to heat the flue gas washing water after the absorption tower and humidify the flue gas. The humidified flue gas returns to the humidification section at the upper end of the absorption tower.

[0027] The regeneration tower is connected to the circulation pump, and the circulating cooling water is used to cool the flue gas washing water, and the generated condensed water is then replenished back to the regeneration tower;

[0028] A wire mesh demister is used in the absorption tower to further treat the flue gas and remove aerosols.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention effectively reduces amine emissions. By adopting specific technical means, the present invention can significantly reduce amine emissions in flue gas and reduce environmental pollution.

[0031] 2. The present invention can reduce energy consumption. By rationally utilizing the heat in the regenerated gas and circulating cooling water, the present invention reduces the energy consumption of the system and improves energy utilization efficiency.

[0032] 3. The present invention can improve system stability: by optimizing the system structure and process flow, the present invention improves the system stability and operating efficiency, and reduces the difficulty of maintenance and operation.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0035] Figure 1 This is a schematic diagram of the system flow structure of a low-amine emission flue gas CO2 capture system proposed in the present invention.

[0036] Figure 2 This is a schematic diagram of the system principle structure of a low-amine emission flue gas CO2 capture system proposed by the present invention.

[0037] In the figure: 1. Absorption tower; 2. Storage tank; 3. Water washing pump; 4. Cooler; 5. Lean and rich liquid heat exchanger; 6. Regeneration tower; 7. Steam reboiler; 8. Circulation pump; 9. Rich liquid pump; 10. Pressure pump; 11. Transfer pump; 12. Fan; 13. Lean liquid pump; 14. Pressure sensor; 15. Central processing unit; 16. Data comparison module; 17. Data storage module; 18. Temperature sensor. DETAILED DESCRIPTION

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0041] In the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0042] like Figure 1 As shown, an embodiment of the present invention provides a low-amine emission flue gas CO2 capture system, comprising an absorption tower 1, one side of the absorption tower 1 is connected to a storage tank 2, a pressure sensor is provided inside the storage tank 2, when the pressure in the storage tank 2 reaches a preset predetermined value, the liquid or gas in the storage tank 2 will automatically pass through the valve to the next stage, a water washing pump 3 and a cooler 4 are provided on one side of the storage tank 2, when the gas enters the water washing pump 3, the water washing pump 3 senses the gas, and then transmits the data to the controller, which controls the water washing pump 3 and the cooler 4 Work, thereby extracting and cooling the gas, and then allowing the gas to enter the interior of the absorption tower 1, a lean-rich liquid heat exchanger 5 is provided on one side of the absorption tower 1, and a regeneration tower 6 is provided on one side of the lean-rich liquid heat exchanger 5. The lean-rich liquid heat exchanger 5 allows the gas to enter the interior of the regeneration tower 6 after heat exchange, and then a steam reboiler 7 is provided on one side of the regeneration tower 6. The water inlet of the water washing pump 3 is connected with the water inlet of the storage tank 2 through a pipeline, and the water outlet of the water washing pump 3 is connected with the water inlet of the cooler 4 through a pipeline, and the water outlet of the cooler 4 is connected with one side of the absorption tower 1 through a pipeline.

[0043] One end of the steam reboiler 7 is connected to a circulation pump 8, one end of the circulation pump 8 is connected to one side of the regeneration tower 6 through a pipeline, one side of the regeneration tower 6 is connected to one side of the lean and rich liquid heat exchanger 5, one side of the absorption tower 1 is connected to a rich liquid pump 9, and one side of the rich liquid pump 9 is connected to the lean and rich liquid heat exchanger 5, one side of the steam reboiler 7 is connected to one side of the regeneration tower 6 through a pipeline, one side of the absorption tower 1 is connected to a transmission pump 11, one end of the transmission pump 11 is connected to one side of the lean and rich liquid heat exchanger 5, a fan 12 is provided on one side of the absorption tower 1, the air outlet of the fan 12 is connected to one side of the absorption tower 1 through a pipeline, a cold rich liquid outlet is provided on one side of the absorption tower 1, and the cold rich liquid outlet is connected to the liquid inlet of the rich liquid pump 9.

[0044] One side of the regeneration tower 6 is connected to a delivery pump, one side of the delivery pump is connected to CO2, the CO2 gas is connected to the top of the regeneration tower 6, and a pressure pump 10 is provided on one side of the regeneration tower 6, one side of the pressure pump 10 is connected to one side of the regeneration tower 6, and one side of the pressure pump 10 is connected to one side of the absorption tower 1 through the storage tank 2.

[0045] like Figure 2 As shown, a pressure sensor 14 is provided inside the storage tank 2, and a central processing unit 15 is provided on one side of the pressure sensor 14. The central processing unit 15 is bidirectionally connected to the pressure sensor 14, and the output end signal of the central processing unit 15 is connected to the transmission pump 11 and the pressure pump 10. The output end of the central processing unit 15 is electrically connected to the water washing pump 3, the cooler 4 and the fan 12 respectively, and the other output end of the central processing unit 15 is electrically connected to the circulation pump 8, the rich liquid pump 9 and the lean liquid pump 13 respectively, and one side of the central processing unit 15 is bidirectionally connected to the data comparison module 16, and one side of the data comparison module 16 is bidirectionally connected to the data storage module 17, the output end of the central processing unit 15 is electrically connected to the temperature sensor 18, and one side of the temperature sensor 18 is bidirectionally connected to the steam reboiler 7, and one end of the central processing unit 15 is electrically connected to the lean and rich liquid heat exchanger 5.

[0046] As a preferred embodiment of this invention, the connection between the pressure pump 10 and the absorption tower 1 is a humidification section, which uses the regeneration gas to heat the flue gas washing water after the absorption tower 1 to humidify the flue gas. By heating the washing water, the small particles and aerosols in the flue gas grow rapidly.

[0047] It is worth noting that the method in the above system is conducive to subsequent separation and removal. At the same time, the heat in the regenerated gas is fully utilized, reducing the energy consumption of the system.

[0048] As a preferred embodiment of this invention, the circulating pump 8 is connected to the steam reboiler 7. The system uses circulating cooling water to cool the flue gas washing water, generating a large amount of condensed water. The formation of condensed water helps to remove large particle droplets and volatile amines, further reducing amine emissions.

[0049] It is worth mentioning that the use of circulating cooling water also reduces the energy consumption of the system.

[0050] As a preference of this embodiment, the absorption tower 1 uses a wire mesh demister to treat the flue gas and remove aerosols therein. The wire mesh demister further treats the flue gas and removes aerosols therein.

[0051] It is worth mentioning that the wire mesh demister has a high-efficiency and stable demisting effect, which can ensure that aerosols in the flue gas are effectively removed.

[0052] As a preferred embodiment of this embodiment, one side of the lean-rich liquid heat exchanger 5 is connected to a lean liquid pump 13, one end of the lean liquid pump 13 is respectively connected to one side of the regeneration tower 6 and the steam reboiler 7, the rich liquid pump 9 and the lean liquid pump 13 are used for water balance control, and the flue gas condensate generated by the steam reboiler 7 is replenished to the regeneration tower 6.

[0053] It is worth noting that this design not only helps to reduce amine emissions, but also improves the stability and operating efficiency of the system.

[0054] In the above technical solutions, the pipelines are all used for liquid and gas transmission, and in actual application, they have anti-corrosion and anti-rust functions. During system transmission, valves need to be installed where necessary for control, which also facilitates the replacement of components in subsequent systems.

[0055] In addition to the above technical solutions, the present invention can also adopt the following alternative solutions to achieve a flue gas CO2 capture system with low amine emissions:

[0056] (1) In this system, other heating methods (such as electric heating) can be used to heat the washing water to achieve flue gas humidification and rapid growth of aerosols. Although this method may increase energy consumption to a certain extent, it can be selected according to actual conditions.

[0057] (2) In this system, other cooling methods (such as air cooling) can be used to cool the washing water to produce condensed water and remove large particle droplets and volatile amines. This method can be selected according to actual conditions and needs to achieve the best demisting and energy saving effects.

[0058] (3) In this system, in addition to the wire mesh demister, other demisting equipment (such as cyclone separators, etc.) can also be considered for demisting treatment. These devices can be selected and optimized according to actual conditions to achieve the best demisting effect.

[0059] The above alternatives can be selected and optimized according to actual needs and conditions to achieve the technical effects and invention objectives required by the present invention.

[0060] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made by those skilled in the art that fall within the spirit and principles of the present invention and do not require creative effort are intended to be within the scope of protection of the present invention.

Claims

1. A flue gas carbon dioxide capture system with low amine emission, characterized by: The invention comprises an absorption tower, one side of which is connected to a storage tank, which is connected in sequence to a water washing pump and a cooler, a lean-rich liquid heat exchanger is provided on the other side of the absorption tower, a regeneration tower is provided on one side of the lean-rich liquid heat exchanger, and a steam reboiler is provided on one side of the regeneration tower; One end of the steam reboiler is connected to a circulation pump, which is connected to the regeneration tower through a pipeline, and the regeneration tower is connected to the lean-rich liquid heat exchanger; One side of the absorption tower is connected to a rich liquid pump, and the rich liquid pump is connected to a lean and rich liquid heat exchanger, and a steam reboiler is connected to a regeneration tower through a pipeline; The regeneration tower is connected to a delivery pump, which is connected to carbon dioxide gas. The carbon dioxide gas is introduced into the top of the regeneration tower. The regeneration tower is also connected to a pressure pump, and the other side of the pressure pump is connected to the absorption tower through a storage tank.

2. A low amine emission flue gas carbon dioxide capture system as claimed in claim 1, characterized in that: A pressure sensor is provided inside the storage tank, and the central processing unit is bidirectionally connected to the pressure sensor. The central processing unit is connected to the transmission pump, pressure pump, water washing pump, cooler, fan, circulation pump, rich liquid pump, lean-rich liquid heat exchanger and lean liquid pump, and the central processing unit is connected to a data comparison module, the data comparison module is connected to a data storage module, and the output end of the central processing unit is electrically connected to a temperature sensor, and the temperature sensor is connected to a steam reboiler.

3. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: The water inlet of the water washing pump is connected to the water inlet of the storage tank through a pipeline, the water outlet of the water washing pump is connected to the water inlet of the cooler through a pipeline, and the water outlet of the cooler is connected to one side of the absorption tower through a pipeline.

4. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: One side of the absorption tower is connected to a transmission pump, and one end of the transmission pump is connected to one side of the lean and rich liquid heat exchanger; The lower end of the absorption tower is connected to a fan, and the air outlet of the fan is connected to the absorption tower through a pipeline.

5. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: A cold rich liquid outlet is provided on one side of the absorption tower, and the cold rich liquid outlet is communicated with the liquid inlet of the rich liquid pump.

6. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: The connection between the pressure pump and the absorption tower is a humidification section, which uses regenerated gas to heat the flue gas tail gas washing water after the absorption tower to humidify the flue gas. By heating the washing water, small particles and aerosols in the flue gas grow rapidly.

7. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: The circulating pump is connected to the steam reboiler and uses circulating cooling water to cool the flue gas washing water, thereby generating a large amount of condensed water.

8. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: The absorption tower is connected to a wire mesh demister, which is used to treat the flue gas and remove aerosols therein.

9. The low amine emission flue gas carbon dioxide capture system according to claim 1, characterized in that: The lean-rich liquid heat exchanger is connected to a lean liquid pump, which is respectively connected to the regeneration tower and the steam reboiler. The rich liquid pump and the lean liquid pump are used for water balance control. The flue gas condensate generated by the steam reboiler is added to the regeneration tower to maintain water balance.

10. A working method based on the system according to any one of claims 1 to 9, characterized in that: The following steps are involved: The aerosol growth section at the upper end of the absorption tower is washed by water from the water washing pump and cooler and then returned to the absorption tower; The cold rich liquid of the absorption tower flows out from the cold rich liquid outlet and is transferred to the lean rich liquid heat exchanger through the rich liquid pump. The cold lean liquid after heat exchange flows back to the absorption tower; The regeneration tower is connected to the lean-rich liquid heat exchanger to heat the flue gas washing water after the absorption tower and humidify the flue gas. The humidified flue gas returns to the humidification section at the upper end of the absorption tower. The regeneration tower is connected to the circulation pump, and the circulating cooling water is used to cool the flue gas washing water, and the generated condensed water is then replenished back to the regeneration tower; A wire mesh demister is used in the absorption tower to further treat the flue gas and remove aerosols.

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