An integrated decarbonization apparatus

Abstract

The utility model relates to a biogas decarburization technical field, is a kind of decarburization equipment to the decarburization of biogas, including decarburization reduction integrated tower, air inlet buffer tank and decarburization liquid circulating tank;The decarburization reduction integrated tower is a sealed reaction vessel, its internal space is tower cavity, and tower cavity is divided into multiple zones, including decarburization zone, flash zone, atmospheric desorption zone from top to bottom, gas stripping desorption zone;The decarburization zone and flash zone are separated by first baffle, and the flash zone and atmospheric desorption zone are separated by second baffle, and the atmospheric desorption zone and gas stripping desorption zone are separated by third baffle;Such integrated integrated decarburization equipment saves site, and dismounting is convenient, and can meet the needs of small-scale biogas decarburization.

Description

Technical Field

[0001] This utility model relates to the field of biogas post-treatment technology in biogas engineering, specifically to a decarbonization tower for decarbonizing biogas. Background Technology

[0002] In biogas projects, the biogas produced by fermentation contains many impurities, including hydrogen sulfide and carbon dioxide. Therefore, the biogas produced in biogas projects needs to undergo desulfurization and decarbonization treatment. Decarbonization treatment of biogas requires decarbonization equipment, which is a modular system with many sub-components, including large sub-components such as decarbonization towers, flash towers, and desorption towers. The decarbonization tower has a decarbonization liquid spraying device that sprays the biogas entering the tower to absorb the carbon dioxide. The flash tower and desorption tower reduce and regenerate the decarbonized rich liquid after carbon dioxide absorption. All components are connected by complex pipelines.

[0003] Therefore, the decarbonization process of biogas requires multiple large components, and these components need to be connected by pipelines, making the installation and construction of the entire decarbonization equipment quite troublesome; it also occupies a lot of space and cannot be arranged in a small plant; moreover, the existing decarbonization equipment is suitable for decarbonizing large-scale biogas (20,000 m³ / d), but for small-scale biogas, the processing capacity is excessive, resulting in waste.

[0004] The purpose of this invention is to address the aforementioned shortcomings by providing an integrated decarbonization treatment device that is easy to install and relocate, occupies a small area, saves space, and can meet the needs of small-scale decarbonization treatment. Summary of the Invention

[0005] The purpose of this utility model is to address the above-mentioned shortcomings by providing a novel decarbonization device, which is an integrated decarbonization device that combines multiple decarbonization components into one structure. It is convenient to install and relocate, requires no debugging, saves space, and can meet the needs of biogas decarbonization of any scale.

[0006] The technical solution of this utility model is implemented as follows: an integrated decarbonization device includes a decarbonization-reduction integrated tower, an inlet buffer tank, and a decarbonization liquid circulation tank; the decarbonization-reduction integrated tower is a sealed reaction vessel, and its internal space is a tower cavity, which is divided into multiple zones, including a decarbonization zone, a flash zone, an atmospheric pressure desorption zone, and a stripping desorption zone from top to bottom; the decarbonization zone and the flash zone are separated by a first partition, the flash zone and the atmospheric pressure desorption zone are separated by a second partition, and the atmospheric pressure desorption zone and the stripping desorption zone are separated by a third partition;

[0007] The gas inlet buffer tank is a container for storing crude biogas. The crude biogas is introduced into the decarbonization zone via a crude biogas transport pipe. A biogas filter, a biogas compressor, a compressed gas cooler, and a biogas refrigerated dryer are sequentially installed on this crude biogas transport pipe. The decarbonization liquid circulation tank is a container for storing decarbonization liquid. The decarbonization liquid circulation tank is connected to the decarbonization zone via a decarbonization liquid output pipe. A first nozzle is installed at the end of the decarbonization liquid output pipe, facing downwards towards the output port of the crude biogas transport pipe. A clean biogas outlet is located on the top wall of the decarbonization zone, connected to a clean biogas output pipe that extends outwards to connect to a gas network. A first pressure regulating valve is installed within the decarbonization zone.

[0008] The sidewall of the flash evaporation zone connects to the inlet buffer tank via a flash overflow pipe, which is equipped with a one-way valve. A second pressure regulating valve is also installed inside the flash evaporation zone. The sidewall of the atmospheric desorption zone has multiple atmospheric vents, which connect to the external environment. The decarbonization zone and the flash evaporation zone are connected by a pipeline, which is equipped with a valve. The flash evaporation zone and the atmospheric desorption zone are connected by a pipeline, which is equipped with a valve. The liquid phase of the liquid phase is connected to the flash evaporation zone via a pipeline, which is equipped with a valve. The sidewall of the gas stripping desorption zone is connected to a gas... The gas discharge pipe is connected to the outside atmosphere. A decarbonization liquid input pipe is installed at the center of the lower surface of the third partition on the top wall of the gas stripping desorption zone. The decarbonization liquid input pipe connects the normal pressure desorption zone and the gas stripping desorption zone. An electronic valve is installed on the decarbonization liquid input pipe, and a second nozzle is installed at the end of the decarbonization liquid input pipe. A Roots blower is also installed in the gas stripping desorption zone, facing the second nozzle. The bottom wall of the gas stripping desorption zone is connected to the decarbonization liquid circulation tank through a return pipe, which is equipped with a pump and a check valve.

[0009] Furthermore, one end of the purified biogas output pipe is connected to the purified biogas outlet, and the other end of the purified biogas output pipe is equipped with a three-way valve. The three-way valve has a one-in-two-out structure, and two purified biogas output branch pipes are led out from the two outlets of the three-way valve. One purified biogas output branch pipe leads to the biogas network, and the other purified biogas output branch pipe leads to the air intake buffer tank. A CO2 tester is installed on the purified biogas output pipe near the three-way valve. The probe of the CO2 tester extends into the purified biogas output pipe, and the CO2 tester and the three-way valve are connected for signal transmission.

[0010] Furthermore, gas-liquid separators are installed on the biogas output pipe, the flash overflow pipe, and the gas discharge pipe, and all gas-liquid separators are connected to the decarbonization liquid recovery tank.

[0011] The beneficial effects are: compared with the existing multi-tank zoning arrangement, this integrated decarbonization equipment integrates the decarbonization tank, flash tank, atmospheric pressure desorption tank and gas stripping desorption tank into one tank, saving space, and is easy to disassemble and assemble, and can meet the needs of small-scale biogas decarbonization. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the integrated decarbonization and reduction tower;

[0013] Figure 2 This is a schematic diagram of the integrated decarbonization equipment in Example 1;

[0014] Figure 3 This is a schematic diagram of the integrated decarbonization equipment in Example 2;

[0015] Figure 4 This is a schematic diagram of the integrated decarbonization equipment in Example 3;

[0016] The structure includes: 1. Decarbonization and reduction integrated tower; 2. Inlet buffer tank; 3. Decarbonization liquid circulation tank; 4. Tower cavity; 5. Decarbonization zone; 6. Flash evaporation zone; 7. Atmospheric pressure desorption zone; 8. Gas stripping desorption zone; 9. First partition; 10. Second partition; 11. Third partition; 12. Coarse biogas transport pipe; 13. Biogas filter; 14. Biogas compressor; 15. Compressed gas cooler; 16. Biogas refrigerated dryer; 17. Decarbonization liquid output pipe; 18. First nozzle; 19. Clean biogas... 20. Gas output pipe; 21. First pressure regulating valve; 22. Flash overflow pipe; 23. Check valve; 24. Second pressure regulating valve; 25. Atmospheric connection port; 251. Valve one; 252. Valve two; 26. Gas discharge pipe; 27. Decarbonized liquid input pipe; 28. Electronic valve; 29. ​​Second nozzle; 30. Roots blower; 31. Return pipe; 32. Pump; 33. Three-way valve; 34. CO2 analyzer; 35. Gas-liquid separator; 36. Decarbonized liquid recovery tank. Detailed Implementation

[0017] The technical solution of this utility model will be further described below with reference to the embodiments.

[0018] Example 1:

[0019] like Figure 1 , 2 As shown, an integrated decarbonization device includes a decarbonization-reduction integrated tower 1, an inlet buffer tank 2, and a decarbonization liquid circulation tank 3. The decarbonization-reduction integrated tower is a sealed reaction vessel with an internal cavity 4. The internal cavity is divided into multiple zones, including, from top to bottom, a decarbonization zone 5, a flash zone 6, an atmospheric pressure desorption zone 7, and a stripping desorption zone 8. The decarbonization zone 5 and the flash zone 6 are separated by a first partition 9, the flash zone 6 and the atmospheric pressure desorption zone are separated by a second partition 10, and the atmospheric pressure desorption zone and the stripping desorption zone are separated by a third partition 11.

[0020] The gas inlet buffer tank is a container for storing crude biogas (undecarbonized biogas). The gas inlet buffer tank 2 is introduced into the decarbonization zone through the crude biogas transport pipe 12. A biogas filter 13, a biogas compressor 14, a compressed gas cooler 15, and a biogas refrigerated dryer 16 are sequentially installed on this crude biogas transport pipe. The decarbonization liquid circulation tank 3 is a container for storing decarbonization liquid. The decarbonization liquid circulation tank 3 is introduced into the decarbonization zone through the decarbonization liquid output pipe 17. A first nozzle 18 is provided at the end of the decarbonization liquid output pipe, facing downwards towards the output port of the crude biogas transport pipe 12. A clean biogas outlet is provided on the top wall of the decarbonization zone 5. The clean biogas outlet is connected to a clean biogas output pipe 19, which leads outwards to connect to the gas network. A first pressure regulating valve 20 is provided in the decarbonization zone.

[0021] The sidewall of the flash zone is connected to the air intake buffer tank through the flash overflow pipe 21. A one-way valve 22 is provided on the flash overflow pipe. A second pressure regulating valve 23 is also provided inside the flash zone.

[0022] The sidewall of the atmospheric desorption zone has an atmospheric connection port 24, which, as the name suggests, is connected to the external environment. There are multiple atmospheric connection ports.

[0023] The decarbonization zone and the flash zone are connected by a pipeline, and valve 251 is installed on the pipeline; the liquid is connected to the flash zone and the atmospheric pressure desorption zone by a pipeline, and valve 252 is installed on the liquid pipeline.

[0024] The side wall of the stripping desorption zone is connected to a gas discharge pipe 26, which is connected to the outside atmosphere. A decarbonization liquid input pipe 27 is installed at the center of the lower surface of the third partition on the top wall of the stripping desorption zone. The decarbonization liquid input pipe connects the normal pressure desorption zone and the stripping desorption zone. An electronic valve 28 is provided on the decarbonization liquid input pipe, and a second nozzle 29 is installed at the end of the decarbonization liquid input pipe. A Roots blower 30 is also installed in the stripping desorption zone, facing the second nozzle.

[0025] The bottom wall of the air stripping desorption zone is connected to the decarbonization liquid circulation tank through the return pipe 31, and the return pipe is equipped with a pump 32 and a check valve.

[0026] Working Principle and Method: The main principle of this device is to utilize the contact between the decarbonization liquid and biogas. The decarbonization liquid absorbs carbon dioxide from the biogas, thus removing carbon dioxide from the biogas. After absorbing carbon dioxide, the decarbonization liquid changes from lean liquid to rich liquid. It needs to be reduced in the rich liquid state to achieve the recycling of the decarbonization liquid. Depending on the stage of decarbonization liquid reduction, it is defined as semi-rich liquid, semi-lean liquid, and lean liquid. It should also be noted that CO2 is easily soluble in decarbonization liquid under high pressure and low temperature. Therefore, before decarbonization, the biogas can be pressurized and cooled to greatly improve the absorption capacity of the decarbonization liquid. However, the decarbonization liquid can absorb a small amount of methane under high pressure. Therefore, a flash evaporation zone is needed to release the small amount of methane to prevent loss.

[0027] The following section will provide further explanation in conjunction with the use of this equipment;

[0028] After the decarbonization process begins, the decarbonization liquid circulation tank is opened, and the first nozzle 18 sprays the decarbonization liquid downwards in the decarbonization zone. At the same time, the air intake buffer tank is opened. The crude biogas in the air intake buffer tank passes through the biogas filter 13 to remove impurities and particulate matter. Then it passes through the biogas compressor 14 to pressurize the biogas to 0.8 MPa. Then it passes through the compressed gas cooler 15 to lower the biogas temperature to a reasonable range. Then it enters the biogas refrigerated dryer 16 to remove free water from the biogas again.

[0029] The treated crude biogas is fed into the decarbonization zone through the crude biogas transport pipe 12. It rises from the bottom of the decarbonization zone and comes into full contact with the decarbonization liquid sprayed from the first nozzle 18 in a counter-current manner, absorbing the carbon dioxide in the biogas. In this way, the crude biogas is decarbonized and becomes clean biogas. The clean biogas is output from the clean biogas output pipe 19 to the gas network pipeline for sale. During this process, it is necessary to control the first pressure regulating valve 20 to control the pressure in the decarbonization zone at 0.8 MPa, so that the decarbonization liquid can absorb CO2 more effectively and remove carbon more efficiently.

[0030] After absorbing CO2, the decarbonized liquid becomes a rich decarbonized liquid. After biogas treatment is complete, the rich decarbonized liquid needs to be reduced. At this point, valve 251 is opened, and the decarbonized liquid from the decarbonization zone enters the flash evaporation zone through a pipeline. The flash evaporation zone is equipped with a second pressure regulating valve 23, which is controlled to maintain the pressure in the flash evaporation zone at 0.35 MPa. This causes a sudden drop in pressure, and the rich decarbonized liquid instantly releases the small amount of methane and some CO2 absorbed within it, becoming a semi-rich liquid. The released small amount of methane and some CO2 return to the intake buffer tank through the flash evaporation overflow pipe 21 for secondary decarbonization and methane recovery, further improving the methane recovery rate. After flash evaporation, valve 251 is closed, and valve 252 is opened. The semi-rich liquid enters the atmospheric desorption zone through a pipeline. The atmospheric desorption zone is connected to the atmosphere... The inlet 24 is connected to the external environment, so the pressure in the atmospheric desorption zone is atmospheric pressure. The semi-rich liquid releases most of its CO2 instantly under atmospheric pressure and is vented. After venting, the semi-rich liquid becomes a semi-lean liquid, which still contains a small amount of CO2. At this point, gas desorption is required. The electronic valve 28 is opened, connecting the decarbonization liquid inlet pipe 27 to the atmospheric desorption zone and the gas stripping desorption zone. The semi-lean liquid enters the gas stripping desorption zone under gravity and is sprayed downwards from the second nozzle 29. At the same time, the Roots blower 30 is turned on, blowing air towards the semi-lean liquid to further release the carbon dioxide. In this way, the CO2 in the semi-lean liquid is fully released, regenerating it into a lean liquid and completing the reduction of the decarbonization liquid. The reduced lean liquid is periodically returned to the decarbonization liquid circulation tank through the return pipe 31, ready for the next round of decarbonization.

[0031] These are all the components and working principles of this decarbonization equipment. Compared with the existing multi-tank zoning layout, this decarbonization equipment integrates the decarbonization tank, flash tank, atmospheric pressure desorption tank, and gas stripping desorption tank into one tank, saving space, and is easy to assemble and disassemble, and can meet the needs of small-scale biogas decarbonization.

[0032] Example 2:

[0033] like Figure 3 As shown, the improvement compared to Embodiment 1 is as follows: one end of the purified biogas output pipe 19 is connected to the purified biogas outlet, and the other end of the purified biogas output pipe 19 is equipped with a three-way valve 33. The three-way valve has a one-in-two-out structure, and two purified biogas output branch pipes 19b are led out from the two outlets of the three-way valve. One purified biogas output branch pipe leads to the biogas network, and the other purified biogas output branch pipe leads to the air intake buffer tank. A CO2 tester 34 is installed on the purified biogas output pipe 19 near the three-way valve. The probe of the CO2 tester extends into the purified biogas output pipe 19, and the CO2 tester and the three-way valve are connected by signal.

[0034] The purpose of this improvement is to use a CO2 tester to constantly test whether the decarbonized biogas is up to standard (whether the CO2 level exceeds the standard). If it is up to standard, a signal is sent to the three-way valve, which controls the biogas to flow into the biogas network. If it is down to standard, a signal is sent to the three-way valve, which controls the biogas to return to the intake buffer tank and decarbonize again until it is up to standard.

[0035] Example 3:

[0036] like Figure 4 As shown, further improvements are made based on Examples 1 and 2. Specifically, gas-liquid separators 35 are provided on the clean biogas output pipe, the flash overflow pipe, and the gas discharge pipe, and all gas-liquid separators are connected to the decarbonization liquid recovery tank 36.

[0037] The purpose of installing a gas-liquid separator is to recover the trace amounts of decarbonized liquid carried by the gas (including biogas, CO2, and methane) discharged from the tower, thus preventing loss.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An integrated decarbonization device, comprising an integrated decarbonization and reduction tower (1), an inlet buffer tank (2), and a decarbonization liquid circulation tank (3); characterized in that, The decarbonization and reduction integrated tower is a sealed reaction vessel. Its internal space is the tower cavity (4). The tower cavity is divided into multiple zones, including the decarbonization zone (5), flash zone (6), atmospheric pressure desorption zone (7), and gas stripping desorption zone (8) from top to bottom. The decarbonization zone and flash zone are separated by a first partition (9), the flash zone and atmospheric pressure desorption zone are separated by a second partition (10), and the atmospheric pressure desorption zone and gas stripping desorption zone are separated by a third partition (11). The intake buffer tank is introduced into the decarbonization zone through the coarse biogas transport pipe (12). The coarse biogas transport pipe is also equipped with devices for pressurizing and drying biogas. The decarbonization liquid circulation tank is introduced into the decarbonization zone through the decarbonization liquid output pipe (17). At the end of the decarbonization liquid output pipe, there is a first nozzle (18) facing downwards towards the output port of the coarse biogas transport pipe. There is a clean biogas outlet on the top wall of the decarbonization zone. The clean biogas outlet is connected to a clean biogas output pipe (19). The clean biogas output pipe is led outwards to connect to the gas network. A first pressure regulating valve (20) is provided in the decarbonization zone. The sidewall of the flash zone is connected to the inlet buffer tank via a flash overflow pipe (21), and a one-way valve (22) is provided on the flash overflow pipe. A second pressure regulating valve (23) is also provided inside the flash zone. The sidewall of the atmospheric desorption zone has an atmospheric connection port (24). The decarbonization zone and the flash zone are connected by a pipeline, and a valve (251) is provided on the pipeline. The flash zone and the atmospheric desorption zone are also connected by a pipeline, and a valve (252) is provided on the liquid pipeline. The sidewall of the gas stripping desorption zone is connected to a gas discharge pipe (26). The gas exhaust pipe is connected to the outside atmosphere. A decarbonization liquid input pipe (27) is installed on the top wall of the gas stripping desorption zone. The decarbonization liquid input pipe connects the normal pressure desorption zone and the gas stripping desorption zone. An electronic valve (28) is provided on the decarbonization liquid input pipe. A second nozzle (29) is installed at the end of the decarbonization liquid input pipe. A Roots blower (30) is also installed in the gas stripping desorption zone. The Roots blower faces the second nozzle. The bottom wall of the gas stripping desorption zone is connected to the decarbonization liquid circulation tank through a return pipe (31). A pump (32) and a check valve are provided on the return pipe.

2. The integrated decarbonization equipment according to claim 1, characterized in that: One end of the biogas output pipe is connected to the biogas outlet, and the other end is equipped with a three-way valve (33). The three-way valve has a one-in-two-out structure. Two biogas output branches are led out from the two outlets of the three-way valve. One biogas output branch leads to the biogas network, and the other biogas output branch leads to the air intake buffer tank. A CO2 tester (34) is installed on the biogas output pipe near the three-way valve. The probe of the CO2 tester extends into the biogas output pipe, and the CO2 tester and the three-way valve are connected by signal.

3. The integrated decarbonization equipment according to claim 1 or 2, characterized in that: Gas-liquid separators (35) are installed on the biogas output pipe, the flash overflow pipe, and the gas discharge pipe. All gas-liquid separators are connected to the decarbonization liquid recovery tank (36).

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