A carbon capture system
By using the water washing, absorption and regeneration process of the carbon capture system, and utilizing organic amine solvents and three-stage filtration technology, the problem of difficult carbon dioxide treatment in the exhaust gas of thermal power plants has been solved, achieving efficient capture and purification of carbon dioxide, and reducing carbon emissions and environmental pollution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGDONG DATANG INT LEIZHOU POWER GENERATION CO
- Filing Date
- 2025-06-21
- Publication Date
- 2026-06-19
AI Technical Summary
The exhaust gas from thermal power plants contains a high concentration of carbon dioxide, which is emitted directly. Existing technologies are unable to effectively capture and treat this carbon dioxide, leading to environmental pollution and exacerbating the greenhouse effect.
A carbon capture system is employed, comprising a washing system, an absorption system, a regeneration system, and a lean liquid filtration system. Through water washing, absorption, and regeneration processes, organic amines are used as solvents to capture carbon dioxide, which is then purified through a three-stage filter to obtain a high-concentration liquid carbon dioxide product.
It achieves efficient carbon dioxide capture, reduces carbon emissions, obtains high-purity carbon dioxide products, and reduces environmental pollution and the greenhouse effect.
Smart Images
Figure CN224371051U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a carbon capture system. Background Technology
[0002] In today's thermal power plants, the main energy conversion process involves burning fossil fuels (such as coal) to generate heat, which then drives generators to produce electricity. However, this process produces large amounts of carbon dioxide emissions, causing serious environmental pollution and contributing to the greenhouse effect.
[0003] Traditional thermal power plants emit exhaust gases containing high concentrations of carbon dioxide, which is released directly into the atmosphere, exacerbating the trend of global warming.
[0004] Carbon capture technology aims to separate and capture carbon dioxide from the exhaust gas of thermal power plants, separating it from the emission stream for subsequent storage or utilization. Post-combustion capture involves separating carbon dioxide from the exhaust gas after fuel combustion through methods such as absorption, adsorption, or membrane separation. Utility Model Content
[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a carbon capture system.
[0006] The above objectives are achieved through the following technical solutions:
[0007] A carbon capture system comprises a scrubbing system, an absorption system, a regeneration system, and a lean liquid filtration system. After boiler dehumidification, the flue gas enters the water scrubbing tower of the scrubbing system. The outlet of the water scrubbing tower of the scrubbing system is connected to the inlet of the absorption tower of the absorption system through a pipeline. The scrubbed flue gas enters the absorption tower to remove carbon dioxide from the flue gas. The amine liquid that absorbs carbon dioxide becomes a rich liquid and enters the bottom of the absorption tower.
[0008] The bottom of the absorption tower is connected to the top of the regeneration tower of the regeneration system via a pipeline. The bottom of the regeneration tower is connected to the inlet of the lean-rich liquid heat exchanger. The lean liquid outlet of the lean-rich liquid heat exchanger is connected to the inlet of the lean liquid cooler. The outlet of the lean liquid cooler is connected to the lean liquid filtration system.
[0009] The carbon capture system includes a washing system comprising a washing tower, a washing tower cooler, and a washing tower pump. The bottom of the washing tower is connected to the inlet of the washing tower pump via a pipeline, the outlet of the washing tower pump is connected to the inlet of the washing tower cooler via a pipeline, and the outlet of the washing tower cooler is connected to a spray pipe at the top of the washing tower.
[0010] The carbon capture system includes an absorption tower, an interstage cooler, and an interstage cooling pump. The middle part of the absorption tower is connected to the inlet of the interstage cooling pump via a pipeline. The outlet of the interstage cooling pump is connected to the inlet of the interstage cooler via a pipeline. The outlet of the interstage cooler is connected to the spray pipe of the absorption tower via a pipeline.
[0011] The carbon capture system includes a regeneration system comprising a regeneration tower, a regeneration gas cooler, and a regeneration gas-liquid separator. The top outlet of the regeneration tower is connected to the inlet of the regeneration gas cooler via a pipeline, and the outlet of the regeneration gas cooler is connected to the inlet of the regeneration gas-liquid separator.
[0012] The carbon capture system and the lean liquid filtration system include a primary filter, a secondary filter and a tertiary filter. The primary filter is a stainless steel wedge filter, the secondary filter is an activated carbon filter, and the tertiary filter is an ultra-fine stainless steel sintered mesh filter. Beneficial effects
[0013] 1. This utility model uses organic amine as a solvent and employs a chemical absorption method to capture carbon dioxide. The flue gas is washed with water, absorbed and regenerated to obtain a high-concentration regenerated gas, which is then compressed, dried, liquefied and purified to obtain a liquid carbon dioxide product, thereby achieving the effect of reducing carbon emissions. Attached Figure Description
[0014] Appendix Figure 1 This is a schematic diagram of the washing system and absorption system of this utility model;
[0015] Appendix Figure 2 This is a schematic diagram of the regeneration system and lean liquid filtration system of this utility model;
[0016] In the diagram: 1. Water washing tower; 2. Absorption tower; 3. Rich solution pump; 4. Lean solution pump; 5. Rich and lean solution heat exchanger; 6. Lean solution cooler; 7. Tertiary filter; 8. Secondary filter; 9. Primary filter; 10. Amine recovery heater; 11. Regeneration gas cooler; 12. Regeneration tower; 13. Regeneration gas-liquid separator; 14. Solution boiler; 15. Interstage cooler; 16. Water washing tower cooler; 17. Water washing tower pump; 18. Alkali storage tank; 19. Alkali metering pump; 20. Interstage cooling pump. Detailed Implementation
[0017] Reference Figures 1-2A carbon capture system comprises a washing system, an absorption system, a regeneration system, and a lean liquid filtration system. After boiler dehumidification, the flue gas enters the water washing tower 1 of the washing system. The outlet of the water washing tower of the washing system is connected to the inlet of the absorption tower 2 of the absorption system through a pipeline. The washed flue gas enters the absorption tower to remove carbon dioxide from the flue gas. The amine liquid that absorbs carbon dioxide becomes a rich liquid and enters the bottom of the absorption tower.
[0018] Main process: bottom liquid pool of the washing tower - washing tower pump - washing tower cooler - top spray atomization of the washing tower. The washing water is equipped with a pH adjustment device, and the acidity and alkalinity of the washing water are controlled by a combination of alkali metering pump, alkali storage tank and pH meter. The washing water is industrial water.
[0019] The bottom of the absorption tower is connected to the top of the regeneration tower 12 of the regeneration system via a pipeline. The bottom of the regeneration tower is connected to the inlet of the lean-rich liquid heat exchanger 5. The lean liquid outlet of the lean-rich liquid heat exchanger is connected to the inlet of the lean liquid cooler 6. The outlet of the lean liquid cooler is connected to the lean liquid filtration system.
[0020] The washing system includes a water washing tower 1, a water washing tower cooler 16, and a water washing tower pump 17. The bottom of the water washing tower is connected to the inlet of the water washing tower pump through a pipeline, the outlet of the water washing tower pump is connected to the inlet of the water washing tower cooler through a pipeline, and the outlet of the water washing tower cooler is connected to the spray pipe at the top of the water washing tower.
[0021] The absorption system includes an absorption tower 2, an interstage cooler 15, and an interstage cooling pump 20. The middle part of the absorption tower is connected to the inlet of the interstage cooling pump through a pipeline, the outlet of the interstage cooling pump is connected to the inlet of the interstage cooler, and the outlet of the interstage cooler is connected to the spray pipe of the absorption tower through a pipeline.
[0022] Flue gas enters the lower part of the carbon dioxide absorption tower from the top outlet of the water scrubbing tower, where it comes into contact with the downward-flowing composite amine solvent, removing over 90% of the carbon dioxide from the flue gas. The amine solution that absorbed the carbon dioxide becomes a rich liquid and enters the bottom of the absorption tower. A water scrubbing section is installed at the top of the absorption tower to capture amine mist entrained in the flue gas and simultaneously condense the moisture in the flue gas to maintain the system's water balance. After being scrubbed by the water scrubbing section, the tail gas is piped back to the chimney for emission. The scrubbing water from the water scrubbing section enters the scrubbing liquid tank, is cooled by the scrubbing liquid cooler, and then recirculates back into the absorption tower. Carbon dioxide absorption is an exothermic reaction; the heat released during absorption needs to be removed to prevent the absorbent temperature from rising, which would reduce its absorption capacity. Simultaneously, a temperature increase would also cause moisture in the amine solution to diffuse into the flue gas, leading to moisture loss within the system. To remove the heat generated during the absorption process, an interstage cooler is installed in the middle section of the carbon dioxide absorption tower. This cools a portion of the absorbent through heat exchange before returning it to the absorption tower, thus maintaining the absorbent at a lower temperature, improving its performance and the carbon dioxide removal rate from the flue gas, and maintaining the overall system's water balance. During operation, the amine solution is carried out of the absorption tower by the flue gas, thus escaping and being consumed. An underground tank and a makeup pump are installed to periodically prepare and replenish the amine solution to the absorption tower.
[0023] The regeneration system includes a regeneration tower 12, a regeneration gas cooler 11, and a regeneration gas-liquid separator 13. The top outlet of the regeneration tower is connected to the inlet of the regeneration gas cooler via a pipeline, and the outlet of the regeneration gas cooler is connected to the inlet of the regeneration gas-liquid separator.
[0024] After carbon dioxide is absorbed by the absorbent in the absorption tower, it is heated by endothermic reaction and then desorbed in the regeneration tower. The desorption process needs to be carried out at around 105℃, so the regeneration unit is a system and equipment centered around the desorption process in the regeneration tower. The rich liquid used to absorb carbon dioxide employs a split-stream desorption process. The rich liquid flows out from the bottom of the absorption tower and is divided into two streams by a rich liquid pump. One stream is directly sent to the top of the regeneration tower as a washing liquid to reduce the temperature and water content at the top of the regeneration tower. The other stream is sent to the lean-rich liquid heat exchanger 5 to recover heat before entering the middle of the regeneration tower. Both rich liquid streams undergo stripping to desorb some carbon dioxide and then enter the solution boiling tank 14 for further desorption. The desorbed carbon dioxide, along with water vapor and some solution, is discharged from the top of the regeneration tower and cooled by the regeneration gas cooler 11. The regeneration gas-liquid separator 13 separates and removes moisture to obtain carbon dioxide product gas with a purity of 99.5% (dry gas) or higher, which is then sent to subsequent processes. Split-stream desorption effectively recovers system heat and reduces the load on the regeneration gas condenser heat exchanger. The lean amine solution at the bottom of the regeneration tower is pressurized by the lean solution pump 4, first passing through a lean-rich solution heat exchanger to recover heat, and then entering the absorption tower through a lean solution cooler 6. Due to the high amount of impurities in the flue gas, amine salts will continuously accumulate in the collection system, causing the absorbent's performance to decline over time. Therefore, to ensure system performance, a portion of the lean amine solution is periodically sent to the amine purification unit for circulation. The lean solution is heated with medium-pressure steam in the amine recovery heater 10, and the vaporized amine enters the bottom of the regeneration tower. The resulting residual liquid is sent to the boiler for incineration.
[0025] The lean liquor filtration system includes a primary filter 9, a secondary filter 8, and a tertiary filter 7. The primary filter is a stainless steel wedge filter, the secondary filter is an activated carbon filter, and the tertiary filter is an ultra-fine stainless steel sintered mesh filter.
[0026] This process employs a highly efficient combined three-stage filtration technology: The first-stage filter uses a stainless steel wedge-type cartridge filter with a filtration accuracy of 25µm. It filters out the large amount of solid particulate matter present in the lean solution system, and periodic backwashing and purging regenerate the metal cartridge. The second-stage activated carbon filter uses a deep filter bed composed of large-capacity, high-iodine-value activated carbon filter media with microporous fermentation. It is particularly suitable for adsorbing organic matter (hydrocarbon condensates, surfactants, lubricating greases, and oxidatively degraded residues) in lean solutions. Its adsorption capacity is 7-10 times that of a traditional activated carbon filter bed. Simultaneously, it coarse-graines and surface-agglomerates foam-like groups present in the solution, destroying the elastic gel layer that forms the foam, reducing foam stability, and causing the foam to break down and aggregate. The third-stage filter uses a large-capacity, ultra-fine stainless steel sintered mesh filter with a filtration accuracy of 5µm, retaining the remaining trace amounts of suspended solids and detached activated carbon particles in the lean solution system.
Claims
1. A carbon capture system characterized by: Its components include: a washing system, an absorption system, a regeneration system, and a lean liquid filtration system. After the boiler is dehumidified, the flue gas enters the water washing tower of the washing system. The outlet of the water washing tower of the washing system is connected to the inlet of the absorption tower of the absorption system through a pipeline. The washed flue gas enters the absorption tower to remove carbon dioxide from the flue gas. The amine liquid that absorbs carbon dioxide becomes rich liquid and enters the bottom of the absorption tower. The bottom of the absorption tower is connected to the top of the regeneration tower of the regeneration system via a pipeline. The bottom of the regeneration tower is connected to the inlet of the lean-rich liquid heat exchanger. The lean liquid outlet of the lean-rich liquid heat exchanger is connected to the inlet of the lean liquid cooler. The outlet of the lean liquid cooler is connected to the lean liquid filtration system.
2. The carbon capture system according to claim 1, characterized in that: The washing system includes a water washing tower, a water washing tower cooler, and a water washing tower pump. The bottom of the water washing tower is connected to the inlet of the water washing tower pump via a pipeline, the outlet of the water washing tower pump is connected to the inlet of the water washing tower cooler via a pipeline, and the outlet of the water washing tower cooler is connected to the spray pipe at the top of the water washing tower.
3. A carbon capture system according to claim 2, characterized in that: The absorption system includes an absorption tower, an interstage cooler, and an interstage cooling pump. The middle part of the absorption tower is connected to the inlet of the interstage cooling pump through a pipeline. The outlet of the interstage cooling pump is connected to the inlet of the interstage cooler. The outlet of the interstage cooler is connected to the spray pipe of the absorption tower through a pipeline.
4. A carbon capture system according to claim 3, characterized in that: The regeneration system includes a regeneration tower, a regeneration gas cooler, and a regeneration gas-liquid separator. The top outlet of the regeneration tower is connected to the inlet of the regeneration gas cooler via a pipeline, and the outlet of the regeneration gas cooler is connected to the inlet of the regeneration gas-liquid separator.
5. A carbon capture system according to claim 4, characterized in that: The lean liquor filtration system includes a primary filter, a secondary filter, and a tertiary filter. The primary filter is a stainless steel wedge filter, the secondary filter is an activated carbon filter, and the tertiary filter is an ultra-fine stainless steel sintered mesh filter.