VOCs tail gas recycling system

Abstract

The utility model relates to the technical field of coal chemical industry, and discloses a VOCs tail gas recycling system which comprises a waste gas washing assembly suitable for being communicated with a VOCs tail gas channel; the gas-liquid separator is provided with a first inlet, a first outlet and a second outlet, and the first inlet is communicated with the waste gas washing assembly; the waste gas recovery assembly is communicated with the first outlet, and the waste gas recovery assembly is suitable for being communicated with the carbonization furnace; the slurry recycling assembly is communicated with the waste gas washing assembly, the slurry recycling assembly is communicated with the second outlet, and the slurry recycling assembly is suitable for being communicated with the washing water channel. According to the utility model, the gas-liquid separator is arranged to perform gas-liquid separation on the washed gas, the waste gas recovery assembly is used to recover the washed gas into the carbonization furnace for reutilization, the slag slurry recovery assembly is used to recover the washed slurry, the treated slurry is communicated to the washing water channel, and the washing water channel is communicated with the washing water channel. Thus, recycling of the VOCs tail gas is completed, and waste gas emission and resource waste are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of coal chemical industry, and particularly relates to a VOCs tail gas recovery and utilization system. Background Art

[0002] Volatile organic compounds (VOCs tail gas) are one of the main sources of air pollution. They participate in the formation of ozone and secondary aerosols in the atmospheric environment and have an important impact on regional atmospheric ozone pollution and PM2.5 pollution. Therefore, the treatment of VOCs tail gas is of crucial importance.

[0003] In the prior art, VOCs tail gas is often washed and then discharged into the atmosphere. However, a large number of valuable components in the VOCs tail gas are not fully utilized. Summary of the Utility Model

[0004] In view of this, the utility model provides a VOCs tail gas recovery and utilization system to solve the problem that a large number of valuable components in the VOCs tail gas are not fully utilized.

[0005] In a first aspect, the utility model provides a VOCs tail gas recovery and utilization system, including: an exhaust gas washing component adapted to be connected to a VOCs tail gas passage; a gas-liquid separator having a first inlet, a first outlet and a second outlet, the first inlet being connected to the exhaust gas washing component; an exhaust gas recovery component connected to the first outlet, the exhaust gas recovery component being adapted to be connected to a carbonization furnace; a slurry recovery component connected to the exhaust gas washing component, the slurry recovery component being connected to the second outlet, and the slurry recovery component being adapted to be connected to a washing water passage.

[0006] Beneficial effects: By providing a gas-liquid separator, the washed gas is separated into gas and liquid. Then, the washed gas is recovered by the exhaust gas recovery component and reused in the carbonization furnace. The washed slurry is recovered and processed by the slurry recovery component, and the processed slurry is connected to the washing water passage, thereby completing the recovery and utilization of VOCs tail gas and reducing waste gas emissions and resource waste.

[0007] In an optional embodiment, the exhaust gas washing component includes a washing tower and a gas cooler. The washing tower has a second inlet, a third inlet, a third outlet and a fourth outlet. The second inlet is adapted to be connected to a washing water passage, the third inlet is adapted to be connected to a VOCs tail gas passage, the third outlet is connected to the first inlet of the gas-liquid separator, and the fourth outlet is connected to the slurry recovery component.

[0008] Beneficial effects: By setting up a scrubbing tower and a gas cooler, the VOCs tail gas is scrubbed and cooled, and the residual coal tar, coke powder, coal powder, etc. in the VOCs tail gas are scrubbed and condensed, which is convenient for subsequent recycling and reduces exhaust pollution.

[0009] In an optional embodiment, the exhaust gas scrubbing assembly includes a cyclone demister, which is arranged in the scrubbing tower and is close to the third outlet.

[0010] Beneficial effects: By setting up a cyclone demister, the moisture content of the gas after scrubbing is reduced, which is convenient for improving the subsequent gas-liquid separation efficiency.

[0011] In an optional embodiment, several scrubbing towers are provided, and the several scrubbing towers are connected in series in sequence.

[0012] Beneficial effects: By setting up several scrubbing towers, the cleaning effect of the exhaust gas scrubbing assembly is further improved.

[0013] In an optional embodiment, the exhaust gas recovery assembly includes an induced draft fan, one end of which is connected to the first outlet, and the other end of which is adapted to be connected to a carbonization furnace.

[0014] Beneficial effects: By setting up an induced draft fan, the gas after gas-liquid separation is introduced into the carbonization furnace for reusing the gas.

[0015] In an optional embodiment, the exhaust gas recovery assembly further includes a gas preheater, which is arranged between the gas-liquid separator and the induced draft fan. One end of the gas preheater is connected to the first outlet, and the other end of the gas preheater is connected to the induced draft fan.

[0016] Beneficial effects: By setting up a gas preheater, the washed gas is heated up so that the partial pressure of water vapor in the washed gas is less than the saturation partial pressure, preventing the precipitation of condensed water from causing pipeline corrosion and blockage.

[0017] In an optional embodiment, the slurry recovery assembly includes a sedimentation tank, which is connected to the exhaust gas scrubbing assembly, is connected to the second outlet, and is adapted to be connected to a washing water channel.

[0018] Beneficial effects: By setting up a sedimentation tank, the slurry after gas-liquid separation and the slurry after scrubbing are subjected to sedimentation treatment, and the clarified liquid after sedimentation is transported to the washing water channel to realize the reuse of water resources.

[0019] In an alternative embodiment, the slurry recovery assembly further includes a filter press. The sedimentation tank has a fourth inlet and a fifth outlet. The filter press is in communication with the fifth outlet and the fourth inlet.

[0020] Advantageous effects: By providing a filter press, the precipitated slurry in the sedimentation tank is recycled, further improving the utilization rate of the VOCs tail gas recovery system.

[0021] In an alternative embodiment, the slurry recovery assembly further includes a flushing structure, which is in communication with the filter press.

[0022] Advantageous effects: By providing a flushing structure, the slurry is further cleaned to ensure the quality of the slurry; it prevents the recycled slurry from having too high viscosity and drying, causing jamming of the machine, and improving the filtration efficiency.

[0023] In an alternative embodiment, the slurry recovery assembly further includes a buffer tank. The sedimentation tank has a sixth outlet. The buffer tank is in communication with the sixth outlet and is adapted to be in communication with the washing water channel.

[0024] Advantageous effects: By providing a buffer tank, a more stable and cleaner water flow can be provided to the washing water channel, reducing water flow fluctuations and preventing water hammer from occurring. Description of the Drawings

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 It is a schematic diagram of a VOCs tail gas recovery system according to an embodiment of the present invention.

[0027] Description of the Reference Numerals:

[0028] 11, washing tower; 12, gas cooler; 13, cyclone demister; 20, gas-liquid separator; 31, induced draft fan; 32, gas preheater; 41, sedimentation tank; 42, filter press; 43, flushing structure; 431, flushing water tank; 432, flushing water pump; 44, buffer tank; 45, slurry pump; 46, skimming oil pump; 47, washing water circulation pump; 48, washing water water cooler; 49, slag powder conveyor; 50, VOCs tail gas channel; 60, production water; 70, coke oven; 80, carbonization furnace; 90, hydrogenation unit; 100, pulverized coal pyrolysis unit. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0030] The following Figure 1 describes the embodiments of the present utility model.

[0031] According to an embodiment of the present utility model, a VOCs tail gas recovery and utilization system is provided, which includes an exhaust gas washing component, a gas-liquid separator 20, an exhaust gas recovery component, and a slurry recovery component. The exhaust gas washing component is adapted to communicate with a VOCs tail gas passage 50; the gas-liquid separator 20 has a first inlet, a first outlet, and a second outlet, and the first inlet is communicated with the exhaust gas washing component; the exhaust gas recovery component is communicated with the first outlet, and the exhaust gas recovery component is adapted to communicate with a carbonization furnace 80; the slurry recovery component is communicated with the exhaust gas washing component, the slurry recovery component is communicated with the second outlet, and the slurry recovery component is adapted to communicate with a washing water passage.

[0032] By applying the VOCs tail gas recovery and utilization system of this embodiment, through the setting of the gas-liquid separator 20, the washed gas is subjected to gas-liquid separation, and then the washed gas is recovered by the exhaust gas recovery component and sent into the carbonization furnace 80 for reuse. The washed slurry is recovered and processed by the slurry recovery component, and the processed slurry is communicated to the washing water passage, thereby completing the recovery and utilization of the VOCs tail gas, reducing exhaust gas emissions and resource waste.

[0033] Specifically, the VOCs tail gas includes the tail gas of the coke pushing system and the tail gas at the top of the carbonization furnace.

[0034] In one embodiment, as Figure 1 shown, the exhaust gas washing component includes a washing tower 11 and a gas cooler 12. The washing tower 11 has a second inlet, a third inlet, a third outlet, and a fourth outlet. The second inlet is adapted to communicate with the washing water passage, the third inlet is adapted to communicate with the VOCs tail gas passage 50, the third outlet is communicated with the first inlet of the gas-liquid separator 20, and the fourth outlet is communicated with the slurry recovery component. By setting the washing tower 11 and the gas cooler 12, the VOCs tail gas is washed and cooled, and the residual coal tar, coke powder, coal powder, etc. in the VOCs tail gas are washed and condensed, which is convenient for subsequent recovery and utilization and reduces exhaust pollution.

[0035] Specifically, the third inlet of the scrubbing tower 11 is arranged below the third outlet, that is, the VOCs tail gas is transported and scrubbed from bottom to top.

[0036] Specifically, as Figure 1 shown, a double-layer water scrubbing spray layer is arranged in the scrubbing tower 11 to facilitate multi-layer absorption and removal of tar, dust, NH3, etc. in the VOCs tail gas.

[0037] Specifically, the nozzles in the scrubbing tower 11 adopt pagoda-shaped nozzles to expand the spray range of the scrubbing water.

[0038] In one embodiment, as Figure 1 shown, the waste gas scrubbing assembly includes a cyclone demister 13. The cyclone demister 13 is arranged in the scrubbing tower 11 and is close to the third outlet. By arranging the cyclone demister 13, the moisture content of the washed gas is reduced to facilitate improving the subsequent gas-liquid separation efficiency.

[0039] In one embodiment, as Figure 1 shown, several scrubbing towers 11 are arranged. The several scrubbing towers 11 are connected in series in sequence. By arranging several scrubbing towers 11, the cleaning effect of the waste gas scrubbing assembly is further improved.

[0040] Specifically, in this embodiment, two scrubbing towers 11 are arranged. The two scrubbing towers 11 are connected in series to fully wash and filter the gaseous coal tar and the carried pulverized coal and coke powder contained in the VOCs tail gas.

[0041] Of course, in other alternative embodiments, the number of scrubbing towers 11 can also be selected according to actual needs, such as two, three, etc.

[0042] In one embodiment, as Figure 1 shown, the waste gas recovery assembly includes a induced draft fan 31. One end of the induced draft fan 31 is communicated with the first outlet, and the other end of the induced draft fan 31 is adapted to be communicated with the carbonization furnace 80. By arranging the induced draft fan 31, the gas after gas-liquid separation is introduced into the carbonization furnace 80 for reutilization of the gas.

[0043] Specifically, the gas after gas-liquid separation includes oxygen, methane, carbon monoxide, hydrogen, etc.

[0044] It should be noted that an explosion detector is also arranged at the outlet of the induced draft fan 31. The components in the gas are analyzed by the explosion detector. If qualified, the gas is introduced into the carbonization furnace 80 for combustion and utilization. If unqualified, the gas is timely emptied and air is introduced in front of the inlet of the induced draft fan 31 to dilute the gas inside the induced draft fan 31.

[0045] In one embodiment, as Figure 1As shown, the waste gas recovery assembly further includes a gas preheater 32, which is arranged between the gas-liquid separator 20 and the induced draft fan 31. One end of the gas preheater 32 is communicated with the first outlet, and the other end of the gas preheater 32 is communicated with the induced draft fan 31. By arranging the gas preheater 32, the washed gas is heated up, so that the partial pressure of water vapor in the washed gas is less than the saturated partial pressure, preventing the precipitation of condensed water and causing pipeline corrosion and blockage.

[0046] In one embodiment, as Figure 1 shown, the slurry recovery assembly includes a sedimentation tank 41, the sedimentation tank 41 is communicated with the waste gas washing assembly, the sedimentation tank 41 is communicated with the second outlet, and the sedimentation tank 41 is suitable for being communicated with the washing water channel. By arranging the sedimentation tank 41, the slurry after gas-liquid separation and the slurry after washing are subjected to sedimentation treatment, and the clarified liquid after sedimentation is transported to the washing water channel to realize the reuse of water resources.

[0047] Specifically, as Figure 1 shown, the sedimentation tank 41 is communicated with the washing tower 11 to collect the washing water at the bottom of the washing tower 11; the sedimentation tank 41 is communicated with the second outlet at the bottom of the gas-liquid separator 20 to collect the liquid water in the gas-liquid separator 20.

[0048] It should be noted that the mixed liquid in the sedimentation tank 41 forms different layers after sedimentation.

[0049] Specifically, the mixed liquid in the sedimentation tank 41 forms a tar layer, a water layer, a coal powder and coke powder layer after sedimentation.

[0050] Specifically, the tar layer is pumped out of the sedimentation tank 41 by a skimming oil pump 46.

[0051] It is worth noting that the tar is transported from the sedimentation tank 41 to the hydrogenation unit 90 as a raw material.

[0052] In one embodiment, as Figure 1 shown, the slurry recovery assembly further includes a filter press 42. The sedimentation tank 41 has a fourth inlet and a fifth outlet. The filter press 42 is communicated with the fifth outlet, and the filter press 42 is communicated with the fourth inlet. By arranging the filter press 42, the precipitated slurry in the sedimentation tank 41 is recycled, further improving the utilization rate of the VOCs tail gas recovery and utilization system.

[0053] Specifically, as Figure 1 shown, the coal powder and coke powder layer deposited at the bottom layer in the sedimentation tank 41 is transported into the filter press 42 by a slurry pump 45.

[0054] Specifically, the filter press 42 in this embodiment adopts a box-type automatic filter press 42, the filter plate material is reinforced polypropylene, and the filter cloth can adopt materials such as polyester, polypropylene, nylon, and vinylon.

[0055] In one embodiment, as Figure 1 shown, the slurry recovery assembly further includes a slag powder conveyor 49, and the slag powder conveyor 49 conveys the pressed slag powder of the filter press 42 to the pulverized coal pyrolysis device 100.

[0056] In one embodiment, as Figure 1 shown, the slurry recovery assembly further includes a flushing structure 43, and the flushing structure 43 is communicated with the filter press 42. By setting the flushing structure 43, the slurry is further cleaned to ensure the quality of the slurry; prevent the viscosity of the recovered slurry from being too high and drying to cause a jamming phenomenon, and improve the filtration efficiency.

[0057] Specifically, as Figure 1 shown, the flushing structure 43 includes a flushing water tank 431 and a flushing water pump 432, and the water in the flushing water tank 431 is pumped into the filter press 42 by the flushing water pump 432.

[0058] Specifically, as Figure 1 shown, the water in the flushing water tank 431 is production water 60.

[0059] In one embodiment, as Figure 1 shown, the slurry recovery assembly further includes a buffer tank 44, the sedimentation tank 41 has a sixth outlet, the buffer tank 44 is communicated with the sixth outlet, and the buffer tank 44 is adapted to be communicated with the washing water channel. By setting the buffer tank 44, a more stable and cleaner water flow can be provided to the washing water channel, reducing the water flow fluctuation and preventing the generation of water hammer.

[0060] Specifically, the buffer tank 44 is also communicated with the production water 60 to facilitate the use of the production water 60 as a supplement for the washing water.

[0061] Specifically, the washing water channel is provided with a washing water circulation pump 47 and a washing water water cooler 48 to facilitate the circulating transportation and cooling of the washing water.

[0062] Specifically, a water channel is further provided in the buffer tank 44 to convey the water in the buffer tank 44 to the coke oven 70 for quenching.

[0063] Apply the VOCs tail gas recovery and utilization system of this embodiment. Pass the VOCs tail gas into the scrubbing tower 11. After the scrubbing tower 11 washes the VOCs tail gas, use the gas cooler 12 to cool the washed gas; after the gas is cooled, it is further processed through the gas-liquid separator 20. The separated gas is heated by the gas preheater 32 and then transported to the carbonization furnace 80 through the induced draft fan 31 for combustion utilization; use the sedimentation tank 41 to collect the washing liquid from the scrubbing tower 11 and the liquid in the gas-liquid separator 20. After the mixed liquid is sedimented and stratified, the tar is pumped out of the sedimentation tank 41 by the skimming oil pump 46 and transported to the hydrogenation unit 90 as raw material. The coal powder and coke powder deposited at the bottom layer in the sedimentation tank 41 are stratified and transported to the filter press 42 by the slurry pump 45 to make slag powder, and the clarified liquid after sedimentation is transported to the buffer tank 44 to realize the reuse of water resources.

[0064] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A VOCs tail gas recovery and utilization system, characterized in that: include: An exhaust gas scrubbing assembly adapted to communicate with a VOCs exhaust gas passage (50); A gas-liquid separator (20) having a first inlet, a first outlet and a second outlet, wherein the first inlet is in communication with the exhaust gas scrubbing assembly; a waste gas recovery component, connected to the first outlet, the waste gas recovery component being adapted to be connected to the carbonization furnace (80); A slurry recovery component is communicated with the exhaust gas washing component, the slurry recovery component is communicated with the second outlet, and the slurry recovery component is suitable for communicating with a washing water channel.

2. The VOCs tail gas recovery and utilization system according to claim 1, characterized in that: The waste gas washing component comprises a washing tower (11) and a gas cooler (12), the washing tower (11) having a second inlet, a third inlet, a third outlet and a fourth outlet, the second inlet being suitable for being connected to a washing water channel, the third inlet being suitable for being connected to a VOCs tail gas channel (50), the third outlet being connected to the first inlet of the gas-liquid separator (20), and the fourth outlet being connected to the slurry recovery component.

3. The VOCs tail gas recovery and utilization system according to claim 2, characterized in that: The exhaust gas washing component comprises a cyclone demister (13), wherein the cyclone demister (13) is arranged in the washing tower (11), and the cyclone demister (13) is arranged close to the third outlet.

4. The VOCs tail gas recovery and utilization system according to claim 2 or 3, characterized in that: A plurality of the washing towers (11) are provided, and the plurality of the washing towers (11) are connected in series in sequence.

5. The VOCs tail gas recovery and utilization system according to any one of claims 1 to 3, characterized in that: The waste gas recovery component comprises an induced draft fan (31), one end of the induced draft fan (31) is in communication with the first outlet, and the other end of the induced draft fan (31) is suitable for being in communication with the carbonization furnace (80).

6. The VOCs tail gas recovery and utilization system according to claim 5, characterized in that: The waste gas recovery component also includes a gas preheater (32), which is arranged between the gas-liquid separator (20) and the induced draft fan (31), one end of the gas preheater (32) is connected to the first outlet, and the other end of the gas preheater (32) is connected to the induced draft fan (31).

7. The VOCs tail gas recovery and utilization system according to any one of claims 1 to 3, characterized in that: The slurry recovery assembly comprises a sedimentation tank (41), the sedimentation tank (41) is communicated with the exhaust gas washing assembly, the sedimentation tank (41) is communicated with the second outlet, and the sedimentation tank (41) is suitable for communicating with a washing water channel.

8. The VOCs tail gas recovery and utilization system according to claim 7, characterized in that: The slurry recovery assembly further comprises a filter press (42), the sedimentation tank (41) has a fourth inlet and a fifth outlet, the filter press (42) is connected to the fifth outlet, and the filter press (42) is connected to the fourth inlet.

9. The VOCs tail gas recovery and utilization system according to claim 8, characterized in that: The slurry recovery assembly further comprises a flushing structure (43), wherein the flushing structure (43) is in communication with the filter press (42).

10. The VOCs tail gas recovery and utilization system according to claim 7, characterized in that: The slurry recovery assembly further comprises a buffer tank (44), the sedimentation tank (41) has a sixth outlet, the buffer tank (44) is in communication with the sixth outlet, and the buffer tank (44) is suitable for being in communication with a washing water channel.

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