VOCs (Volatile Organic Compounds) cooperative treatment system in tar and ammonia water separation

Abstract

The utility model belongs to the technical field of VOCs treatment systems, and particularly discloses a VOCs cooperative treatment system in a tar ammonia water separation process, which comprises a shell, a three-way catalyst and a biological filter tower, the bottom and the top of the shell are communicated with an air inlet and an air outlet pipe, tube plates are arranged on the upper side and the lower side in the shell, a plurality of heat exchange tubes are communicated between the tube plates, and the heat exchange tubes are communicated with the three-way catalyst. A conical disc is arranged at the bottom end of the pipe plate, oil outlet pipes are arranged on the two sides of the bottom of the shell, gate valves are arranged on the oil outlet pipes, one side of the shell is communicated with a condensation water inlet pipe and a condensation water outlet pipe, an electric heater is arranged on the air outlet pipes, the air outlet pipes are communicated with a three-way catalyst, the three-way catalyst is communicated with a biological filter tower, and a filter unit and a spraying unit are arranged in the biological filter tower. The problem that the purification effect is not ideal due to the fact that an existing single process is difficult to deal with multi-component complex waste gas is solved. According to the utility model, through linkage of condensation, catalysis and biological purification, the synergistic effect of VOCs degradation and peculiar smell elimination is realized, and the purification effect of waste gas is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to VOCs processing system technical field, concretely relates to a tar ammonia water separation process VOCs collaborative processing system. BACKGROUND

[0002] Tar ammonia water separation is a key link in coking, coal gasification and other industrial processes, and a tar ammonia water separation tank can produce a large amount of waste gas containing volatile organic compounds (VOCs) and accompanied by strong odor. These waste gas components are complex, including benzene series, hydrogen sulfide, ammonia and other harmful substances, which not only pollute the environment, but also cause harm to human health.

[0003] The existing treatment technology often adopts a single process, such as simple condensation, catalytic oxidation or biological purification, etc. The single process is difficult to cope with multi-component complex waste gas, and cannot comprehensively treat high-boiling and low-boiling VOCs and odor gas, resulting in unsatisfactory purification effect. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a tar ammonia water separation process VOCs collaborative processing system to solve the problem that the existing single process is difficult to cope with multi-component complex waste gas, resulting in unsatisfactory purification effect.

[0005] To achieve the above-mentioned purpose, the basic scheme provided by the utility model is: a tar ammonia water separation process VOCs collaborative processing system, comprising a shell, a three-way catalyst and a biological filter tower, the bottom and top of the shell are communicated with a gas inlet and an exhaust pipe, the shell is provided with tube sheets on the upper and lower sides, a plurality of heat exchange tubes are communicated between the two tube sheets, the bottom end of the tube sheet located at the bottom of the shell is provided with a conical disc, the diameter of the conical disc is greater than the inner diameter of the gas inlet, the bottom of the shell is provided with an oil outlet pipe on both sides, the oil outlet pipe is provided with a gate valve, the shell is respectively communicated with a condensation water inlet pipe and a condensation water outlet pipe on one side, the exhaust pipe is provided with an electric heater, the exhaust pipe is communicated with the three-way catalyst, the exhaust end of the three-way catalyst is communicated with the biological filter tower, and the biological filter tower is provided with a filter unit and a spraying unit.

[0006] The working principle of the utility model is that: when the waste gas needs to be treated, the waste gas enters the shell through the gas inlet first (the initial temperature of the waste gas is 120 DEG C), then the waste gas enters each heat exchange tube, at the same time, the condensation water enters the shell side from the condensation water inlet pipe, and exchanges heat with each heat exchange tube, so that the temperature of the waste gas in the heat exchange tube is reduced to below 40 DEG C, the high-boiling VOCs in the waste gas is condensed into liquid heavy tar fraction, and the liquid heavy tar fraction after condensation flows downward under the action of gravity and is collected to the bottom of the shell under the guidance of the conical disc, and when a certain amount is accumulated, it is discharged through the oil outlet pipe and the gate valve.

[0007] And the exhaust gas that is not condensed enters the outlet pipe, and then enters the electric heater and is heated to 250-350 DEG C, and then the high-temperature exhaust gas enters the three-way catalyst, under the action of the catalyst, low-boiling VOCs (such as benzene series) are oxidized into CO2 and H2O, and the catalyzed gas enters the biological filter tower, and is sequentially degraded and filtered by the filtering unit and the spraying unit, and the gas is finally discharged through the outlet at the top of the biological filter tower.

[0008] The beneficial effects of the utility model lie in: through multistage collaborative processing, condensation-catalysis-biological purification linkage, preferentially separating high-boiling VOCs (such as tar fraction), then degrading low-boiling organic matter (such as benzene series) through three-way catalytic oxidation (250-350 DEG C), and finally adsorbing odor gas through the biological filter tower (spraying + filtering), thereby realizing the synergistic effect of VOCs degradation and odor elimination, and improving the purification effect of the exhaust gas.

[0009] Scheme three, this is the preferred scheme two, the preheating bin is equipped with a plurality of branch pipes, and the two ends of the branch pipe are communicated with the two side outlet pipes;A plurality of branch pipes are arranged in the preheating bin, which can increase the heat exchange area and further improve the heat exchange efficiency.

[0010] Scheme four, this is the preferred basic scheme, the filtering unit comprises activated carbon and volcanic rock filter material, the biological filter tower is respectively provided with a first filter plate and a second filter plate, the activated carbon is located on the first filter plate, and the volcanic rock filter material is located on the second filter plate;The activated carbon and volcanic rock filter material can adsorb odor gas.

[0011] Scheme five, this is the preferred basic scheme, the spraying unit comprises a spraying pipe, the spraying pipe is fixedly penetrated through one side of the biological filter tower, the outlet end of the spraying pipe is provided with a conical uniform distribution plate, and the bottom of the biological filter tower is provided with a liquid outlet pipe;By arranging the spraying pipe and the conical uniform distribution plate, the spraying liquid can be uniformly sprayed to degrade residual odor gas, the spraying liquid contains ammonia oxidizing bacteria and sulfur bacillus, and the bacterial population density is greater than or equal to 10 6 CFU / mL.

[0012] Scheme six, this is the preferred basic scheme, the heat exchange pipe is in spiral shape;The heat exchange pipe is arranged in spiral shape, so that the heat exchange time of the exhaust gas is prolonged, and the heat exchange efficiency is improved.

[0013] Option 7, which is a preferred option of the basic option, has a conical ring at the bottom of the shell and the conical block is located outside the air inlet; by setting the conical ring, high-boiling-point VOCs (such as naphthalene and anthracene) in the tar can be condensed and recovered. Attached Figure Description

[0014] Figure 1 This is a flowchart of a VOCs co-treatment system for a tar-ammonia-water separation process according to this utility model;

[0015] Figure 2 This is a schematic diagram of the shell structure in a VOCs co-treatment system for a tar-ammonia-water separation process according to this utility model. Detailed Implementation

[0016] The present invention will be further described in detail below through specific embodiments:

[0017] The reference numerals in the accompanying drawings of the instruction manual include: 1. Shell; 2. Three-way catalytic converter; 3. Biofilter tower; 4. Air inlet; 5. Air outlet pipe; 6. Tube sheet; 7. Heat exchange tube; 8. Conical disc; 9. Oil outlet pipe; 10. Gate valve; 11. Condensate inlet pipe; 12. Condensate outlet pipe; 13. Electric heater; 14. Preheating chamber; 15. Drain pipe; 16. Branch pipe; 17. Activated carbon; 18. Volcanic rock filter media; 19. First filter plate; 20. Second filter plate; 21. Spray pipe; 22. Conical distribution plate; 23. Liquid outlet pipe; 24. Conical block.

[0018] like Figure 1 and Figure 2The diagram shows a VOCs co-treatment system for a tar-ammonia-water separation process, comprising a shell 1, a three-way catalytic converter 2, and a biofilter 3. The bottom and top of the shell 1 are connected to an inlet 4 and an outlet pipe 5. Tube sheets 6 are installed on both the upper and lower sides of the shell 1, with several heat exchange tubes 7 connected between the two tube sheets 6. The heat exchange tubes 7 are spirally arranged. Several baffles are installed inside the shell 1, and each heat exchange tube 7 is fixedly inserted through a baffle. By setting the baffles, the flow path of steam can be extended, improving heat exchange efficiency. A conical disk 8 is installed at the bottom end of the tube sheet 6 at the bottom of the shell 1. High-boiling-point VOCs (such as naphthalene and anthracene) in the condensed and recovered tar are in liquid state. The diameter of the conical disk 8 is larger than the inner diameter of the inlet 4, which can prevent the condensed heavy tar fraction from entering the inlet 4. A conical ring 24 is installed at the bottom of the shell 1, with the conical block 24 located outside the inlet 4. An oil outlet pipe 9 is provided on the side, and a gate valve 10 is provided on the oil outlet pipe 9. A sight glass is provided on the side near the oil outlet pipe 9 to facilitate observation of the accumulation of heavy tar fractions. A condensate inlet pipe 11 and a condensate outlet pipe 12 are respectively connected to one side of the shell 1. The condensate inlet pipe 11 is located directly above the condensate outlet pipe 12. An electric heater 13 is provided on the gas outlet pipe 5. The electric heater 13 is a tubular electric heater. The gas outlet pipe 5 is connected to the three-way catalytic converter 2. The gas outlet end of the three-way catalytic converter 2 is connected to the biofilter tower 3. The three-way catalytic converter 2 is a Mn-Ce-Co three-way catalyst supported on a honeycomb ceramic carrier. A preheating chamber 14 is fitted on the gas outlet pipe 5 located in front of the electric heater 13. The condensate outlet pipe 12 is connected to the preheating chamber 14. A drain pipe 15 is provided on the preheating chamber 14. Several branch pipes 16 are provided in the preheating chamber 14. The two ends of the branch pipes 16 are connected to the gas outlet pipes 5 on both sides.

[0019] The biofilter tower 3 is equipped with a filtration unit and a spraying unit. The filtration unit includes activated carbon 17 and volcanic rock filter media 18. The biofilter tower 3 is equipped with a first filter plate 19 and a second filter plate 20, with activated carbon 17 located on the first filter plate 19 and volcanic rock filter media 18 located on the second filter plate 20. The spraying unit includes a spray pipe 21, which is fixedly inserted through one side of the biofilter tower 3. A conical distribution plate 22 is provided at the outlet end of the spray pipe 21. A liquid outlet pipe 23 is provided at the bottom of the biofilter tower 3, and an outlet for gas discharge is provided at the top. The spray liquid in the spray pipe 21 contains ammonia-oxidizing bacteria and thiobacilli, with a bacterial density ≥10. 6 CFU / mL.

[0020] The implementation method of this embodiment is as follows: When it is necessary to treat the waste gas, the waste gas first enters the shell 1 through the air inlet 4 (the initial temperature of the waste gas is 120°C), and then the waste gas enters each heat exchange tube 7. At the same time, the condensate enters the shell side of the shell 1 from the condensate inlet pipe 11 and exchanges heat with each heat exchange tube 7, thereby reducing the temperature of the waste gas in the heat exchange tube 7 to below 40°C. The high boiling point VOCs in the waste gas condense into liquid heavy tar fraction. The condensed liquid heavy tar fraction flows downward under the action of gravity and collects at the bottom of the shell 1 under the guidance of the conical disk 8. Observed through the sight glass, when it accumulates to a certain amount, it is discharged through the oil outlet pipe 9 and the gate valve 10.

[0021] The uncondensed exhaust gas enters the outlet pipe 5, and then enters several branch pipes 16 within the preheating chamber 14. Simultaneously, condensate from the condensate outlet pipe 12 enters the preheating chamber 14, where the residual heat of the condensate preheats the exhaust gas, reducing subsequent electric heating energy consumption. The preheated exhaust gas then enters the electric heater 13 and is heated to 250–350°C. The high-temperature exhaust gas then enters the three-way catalytic converter 2, where, under the action of the Mn-Ce-Co three-way catalyst, low-boiling-point VOCs (such as benzene compounds) are oxidized into CO2 and H2. 2O, the catalyzed gas enters the biofilter tower 3, the spray pipe 21 sprays the circulating liquid containing ammonia oxidizing bacteria and thiobacilli evenly through the conical distribution plate 22, degrades odor components such as NH3 and H2S, the spray liquid is discharged through the outlet pipe 23, and the degraded gas moves upward and passes through the activated carbon 17 filled on the first filter plate 19 in sequence to adsorb residual VOCs and odor molecules, the volcanic rock filter material 18 filled on the second filter plate 20 further adsorbs odor molecules, and the gas is finally discharged through the outlet at the top of the biofilter tower 3.

[0022] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A VOCs co-treatment system for a tar-ammonia-water separation process, characterized in that, The device includes a shell (1), a three-way catalytic converter (2), and a biofilter (3). The bottom and top of the shell (1) are connected to an air inlet (4) and an air outlet (5). Tube sheets (6) are provided on both the upper and lower sides of the shell (1). Several heat exchange tubes (7) are connected between the two tube sheets (6). A conical disk (8) is provided at the bottom end of the tube sheet (6) at the bottom of the shell (1). The diameter of the conical disk (8) is larger than the inner diameter of the air inlet (4). Oil outlet pipes (9) are provided on both sides of the bottom of the shell (1). A gate valve (10) is provided on the oil outlet pipe (9). A condensate inlet pipe (11) and a condensate outlet pipe (12) are respectively connected to one side of the shell (1). An electric heater (13) is provided on the air outlet pipe (5). The air outlet pipe (5) is connected to the three-way catalytic converter (2). The air outlet end of the three-way catalytic converter (2) is connected to the biofilter (3). The biofilter (3) is provided with a filtration unit and a spray unit.

2. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 1, characterized in that, A preheating chamber (14) is fitted on the air outlet pipe (5) located in front of the electric heater (13). The condensate outlet pipe (12) is connected to the preheating chamber (14). A drain pipe (15) is provided on the preheating chamber (14).

3. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 2, characterized in that, The preheating chamber (14) is provided with several branch pipes (16), and the two ends of the branch pipes (16) are connected to the air outlet pipes (5) on both sides.

4. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 1, characterized in that, The filtration unit includes activated carbon (17) and volcanic rock filter media (18). The biofilter tower (3) is provided with a first filter plate (19) and a second filter plate (20). The activated carbon (17) is located on the first filter plate (19), and the volcanic rock filter media (18) is located on the second filter plate (20).

5. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 1, characterized in that, The spray unit includes a spray pipe (21), which is fixedly inserted through one side of the biofilter tower (3). The outlet end of the spray pipe (21) is provided with a conical uniform distribution plate (22), and the bottom of the biofilter tower (3) is provided with a liquid outlet pipe (23).

6. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 1, characterized in that, The heat exchange tube (7) is spiral-shaped.

7. The VOCs co-treatment system for tar-ammonia-water separation process according to claim 1, characterized in that, The bottom of the housing (1) is provided with a conical ring (24), which is located outside the air inlet (4).

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