Carbon dioxide trapping and recycling device for chimney exhaust gas

Abstract

The utility model discloses a carbon dioxide capture and recovery device for chimney exhaust gas, which relates to the technical field of carbon dioxide recovery and comprises a pretreatment tower, an absorption tower, a regeneration tower and a storage device. The pretreatment tower is communicated with a flue gas pipeline and is communicated with the absorption tower through a temperature adjusting device; the absorption tower is provided with an exhaust pipeline, the absorption tower is communicated with the flow dividing device, rich liquor is subjected to flow dividing, then heat exchange is conducted through the lean and rich liquor heat exchanger and the gas-liquid heat exchanger, then the rich liquor is converged and communicated with the regeneration tower through the heater, and the regeneration tower is communicated with the storage device through the first lean liquor pump and the lean and rich liquor heat exchanger; the storage device is communicated with the absorption tower through a second barren liquor pump and a cooler, and the regeneration tower is communicated through a gas-liquid separator and a gas-liquid heat exchanger in sequence. According to the utility model, high-temperature barren liquor and high-temperature carbon dioxide gas are respectively subjected to heat exchange, so that the heat utilization rate is increased and energy is saved; the storage is arranged to improve the buffering capacity, and whether absorption liquid needs to be added or not is judged conveniently.

Description

Technical Field

[0001] The utility model relates to the technical field of carbon dioxide recovery, in particular to a carbon dioxide capture and recovery device for chimney exhaust gas. Background Art

[0002] Industrial flue gas contains a large amount of carbon dioxide. Reducing carbon dioxide emissions not only reduces greenhouse gas emissions and helps improve the atmospheric environment, but also recovering carbon dioxide in flue gas can realize its resource utilization, such as being an important raw material for inorganic chemical production, organic chemical production, organic polymer compound synthesis and other production processes, bringing practical economic benefits.

[0003] The existing carbon dioxide capture and recovery device has a low heat recovery efficiency for the regeneration tower, resulting in a waste of resources. Therefore, how to provide a carbon dioxide capture and recovery device for chimney exhaust gas that can improve the heat recovery rate and improve the buffering capacity of the system has become a problem that technicians in this field need to solve urgently. Utility Model Content

[0004] The utility model aims to provide a device for capturing and recovering carbon dioxide for chimney exhaust gas, so as to solve the problem of low heat recovery rate.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] The utility model discloses a carbon dioxide capture and recovery device for chimney exhaust gas, comprising a pretreatment tower, a temperature regulating device, an absorption tower, a flow dividing device, a lean-rich liquid heat exchanger, a gas-liquid heat exchanger, a heater, a regeneration tower, a reboiler, a storage device, a cooler and a gas-liquid separator;

[0007] The air inlet end of the pretreatment tower is communicated with the flue gas duct, and the air outlet end of the pretreatment tower is communicated with the absorption tower after passing through the temperature regulating device; an exhaust duct is arranged on the top of the absorption tower, and the liquid outlet end of the absorption tower is communicated with the diversion device through a rich liquid pump, the lean-rich liquid heat exchanger is arranged on the first branch of the diversion device, and the gas-liquid heat exchanger is arranged on the second branch of the diversion device. After the first branch and the second branch are merged, they are communicated with the liquid inlet of the regeneration tower through the heater, the bottom of the regeneration tower is communicated with the lower right side of the regeneration tower through the reboiler, the liquid outlet end of the regeneration tower is communicated with the storage device through the first lean liquid pump and the lean-rich liquid heat exchanger in sequence, the liquid outlet end of the storage device is communicated with the liquid inlet pipe of the absorption tower through the second lean liquid pump and the cooler, and the air outlet end of the regeneration tower is communicated with the processing system after passing through the gas-liquid separator and the gas-liquid heat exchanger in sequence.

[0008] Preferably, a liquid level meter and a concentration monitor are provided inside the storage.

[0009] Preferably, a fluid replenishment tank is further provided, and the fluid replenishment tank is connected to the storage via a fluid replenishment pump.

[0010] Preferably, the liquid replenishing tank is provided with a adding port.

[0011] Preferably, the liquid phase outlet of the gas-liquid separator is communicated with the storage.

[0012] Preferably, a wire mesh demister is provided at the exhaust pipe of the absorption tower.

[0013] Compared with the prior art, the beneficial technical effects of the utility model are:

[0014] 1) The rich liquid is divided into two parts through a splitter device, and heat is exchanged with the high-temperature lean liquid and the high-temperature carbon dioxide gas respectively, thereby improving the utilization rate of heat and saving energy;

[0015] 2) A storage device is provided as a temporary storage device for the absorption liquid, which is convenient for monitoring the concentration of the absorption liquid during the circulation process and judging whether the absorption liquid should be replaced or added. At the same time, it can make the system have a certain buffering capacity to avoid a series of problems caused by long-term low absorption liquid due to poor supervision.

[0016] The utility model discloses a carbon dioxide capture and recovery device for chimney exhaust gas, which is provided with a diverter device, through which a rich liquid is divided into two parts in proportion, and heat is exchanged with a high-temperature lean liquid and a high-temperature carbon dioxide gas respectively, so as to improve the utilization rate of heat and save energy; a storage device is also provided as an absorption liquid temporary storage device, which is convenient for monitoring the concentration content of the absorption liquid during the circulation process, and judging whether the absorption liquid should be replaced or added, and at the same time, it can make the system have a certain buffering capacity, so as to avoid a series of problems caused by the absorption liquid being too low for a long time due to poor supervision. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The utility model will be further described below in conjunction with the accompanying drawings.

[0018] Figure 1 It is a schematic diagram of the carbon dioxide capture and recovery device for chimney exhaust gas of the utility model.

[0019] Explanation of the reference numerals: 1. pretreatment tower; 2. temperature regulating device; 3. absorption tower; 4. rich liquid pump; 5. diversion device; 6. lean and rich liquid heat exchanger; 7. gas-liquid heat exchanger; 8. heater; 9. regeneration tower; 10. reboiler; 11. first lean liquid pump; 12. storage device; 13. second lean liquid pump; 14. cooler; 15. gas-liquid separator; 16. liquid replenishing tank; 17. liquid replenishing pump. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] like Figure 1 As shown, a device for capturing and recovering carbon dioxide from chimney exhaust gas comprises a pretreatment tower 1, a temperature regulating device 2, an absorption tower 3, a flow dividing device 5, a lean-rich liquid heat exchanger 6, a gas-liquid heat exchanger 7, a heater 8, a regeneration tower 9, a reboiler 10, a storage device 12, a cooler 14 and a gas-liquid separator 15;

[0022] The air inlet end of the pretreatment tower 1 is connected to the flue gas pipeline, and the air outlet end of the pretreatment tower 1 is connected to the absorption tower 3 after passing through the temperature regulating device 2; the top of the absorption tower 3 is provided with an exhaust pipeline, and the liquid outlet end of the absorption tower 3 is connected to the diversion device 5 through the rich liquid pump 4, and the lean-rich liquid heat exchanger 6 is provided on the first branch of the diversion device 5, and the gas-liquid heat exchanger 7 is provided on the second branch of the diversion device 5. After the first branch and the second branch are merged, the heat exchanger 8 is connected to the gas-liquid heat exchanger 7. The liquid inlet of the regeneration tower 9 is connected, the bottom of the regeneration tower 9 is connected to the lower right side of the regeneration tower 9 through the reboiler 10, the liquid outlet of the regeneration tower 9 is connected to the storage device 12 through the first lean liquid pump 11 and the lean-rich liquid heat exchanger 6 in sequence, the liquid outlet of the storage device 12 is connected to the liquid inlet pipeline of the absorption tower 3 through the second lean liquid pump 13 and the cooler 14, and the gas outlet of the regeneration tower 9 is connected to the processing system after passing through the gas-liquid separator 15 and the gas-liquid heat exchanger 7 in sequence.

[0023] Specifically, a liquid level meter and a concentration monitor are provided inside the storage 12; the liquid level meter and the concentration monitor respectively detect the content and concentration of the absorption liquid in the storage 12, so that the staff can perform liquid replenishment or replacement operations.

[0024] Specifically, a refill tank 16 is provided, and the refill tank 16 is connected to the storage 12 via a refill pump 17 ; when it is detected that the liquid level in the storage 12 drops below a preset value, the refill pump 17 pumps the absorption liquid in the refill tank 16 into the storage 12 .

[0025] Specifically, the rehydration tank 16 is provided with a adding port; the staff can add the absorption liquid or other regulator into the rehydration tank 16 through the adding port.

[0026] Specifically, the liquid phase outlet of the gas-liquid separator 15 is connected to the storage device 12; the gas-liquid separator 15 performs gas-liquid separation on the carbon dioxide discharged from the regeneration tower 9, which can improve the purity of the carbon dioxide, prevent the carbon dioxide from carrying liquid and affecting the working efficiency of the gas-liquid heat exchanger 7, and reduce the loss of the absorption liquid.

[0027] Specifically, a wire mesh demister is provided at the exhaust duct of the absorption tower 3; the provision of the wire mesh demister can prevent the emission of absorption liquid droplets in the filtered flue gas, which can not only ensure the air quality but also reduce the loss of absorption liquid.

[0028] The use process of the utility model is as follows:

[0029] In the preparation stage, the flue gas from the flue gas pipeline is passed into the pretreatment tower 1 for desulfurization and denitrification treatment, and then after being adjusted to a suitable temperature by the temperature adjustment device 2, it is passed into the absorption tower 3 for reaction, and the reacted gas is discharged into the atmosphere through the exhaust pipe;

[0030] In the preparation stage, the absorption liquid absorbs carbon dioxide inside the absorption tower 3 to form a rich liquid, and the rich liquid is pumped into the diversion device through the rich liquid pump 4. The diversion device is divided into a first branch pipe and a second branch pipe according to a preset value. The rich liquid in the first branch pipe exchanges heat with the lean liquid from the regeneration tower through the lean-rich liquid heat exchanger 6, and then merges with the second branch pipe. The rich liquid in the second branch pipe exchanges heat with the carbon dioxide from the regeneration tower through the gas-liquid heat exchanger 7, and then merges with the first branch pipe. The merged rich liquid is heated by the heater 8 and enters the regeneration tower 9 to release carbon dioxide, releasing the two The lean liquid after carbon oxidation is passed through the first lean liquid pump 11 and then exchanges heat with the rich liquid in the first branch pipe in the lean-rich liquid heat exchanger 6 and enters the storage 12. The absorption liquid in the storage 12 is cooled by the second lean liquid pump 13 through the cooler 14 and then enters the absorption tower 3 for circulation; the carbon dioxide in the regeneration tower 9 is separated from the absorbent by the gas-liquid separator 15, and then exchanges heat with the rich liquid in the second branch pipe in the gas-liquid heat exchanger 7, and then enters the subsequent processing system; the absorbent separated by the gas-liquid separator 15 enters the storage 12 through the pipeline for recovery;

[0031] The storage 12 is internally provided with a liquid level meter and a concentration monitor. When it is detected that the liquid level in the storage 12 drops below a preset value, the liquid replenishment pump 17 starts and pumps the absorption liquid in the liquid replenishment tank 16 into the storage 12 .

[0032] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0033] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A device for capturing and recovering carbon dioxide from chimney exhaust gas, characterized in that: It comprises a pretreatment tower (1), a temperature regulating device (2), an absorption tower (3), a flow dividing device (5), a lean-rich liquid heat exchanger (6), a gas-liquid heat exchanger (7), a heater (8), a regeneration tower (9), a reboiler (10), a storage device (12), a cooler (14) and a gas-liquid separator (15); The air inlet end of the pretreatment tower (1) is connected to the flue gas pipeline, and the air outlet end of the pretreatment tower (1) is connected to the absorption tower (3) after passing through the temperature regulating device (2); an exhaust pipeline is arranged on the top of the absorption tower (3), and the liquid outlet end of the absorption tower (3) is connected to the diversion device (5) through a rich liquid pump (4); the lean-rich liquid heat exchanger (6) is arranged on the first branch of the diversion device (5), and the gas-liquid heat exchanger (7) is arranged on the second branch of the diversion device (5); after the first branch and the second branch are merged, they are connected to the reheating device (7) through the heater (8). The liquid inlet of the regeneration tower (9) is connected, the bottom of the regeneration tower (9) is connected to the lower right side of the regeneration tower (9) through the reboiler (10), the liquid outlet of the regeneration tower (9) is connected to the storage device (12) through the first lean liquid pump (11) and the lean-rich liquid heat exchanger (6) in sequence, the liquid outlet of the storage device (12) is connected to the liquid inlet pipeline of the absorption tower (3) through the second lean liquid pump (13) and the cooler (14), and the gas outlet of the regeneration tower (9) is connected to the processing system after passing through the gas-liquid separator (15) and the gas-liquid heat exchanger (7) in sequence.

2. The device for capturing and recovering carbon dioxide from chimney exhaust gas according to claim 1, characterized in that: A liquid level meter and a concentration monitor are arranged inside the storage (12).

3. The device for capturing and recovering carbon dioxide from chimney exhaust gas according to claim 1, characterized in that: A fluid replenishment tank (16) is also provided, and the fluid replenishment tank (16) is connected to the storage (12) via a fluid replenishment pump (17).

4. The device for capturing and recovering carbon dioxide from chimney exhaust gas according to claim 3, characterized in that: The liquid replenishing tank (16) is provided with a filling port.

5. The device for capturing and recovering carbon dioxide from chimney exhaust gas according to claim 1, characterized in that: The liquid phase outlet of the gas-liquid separator (15) is in communication with the storage device (12).

6. The device for capturing and recovering carbon dioxide from chimney exhaust gas according to claim 1, characterized in that: A wire mesh demister is provided at the exhaust pipe of the absorption tower (3).

Images