Waste gas collection and treatment system for coking closed decoking device

Abstract

A waste gas collection and treatment system for a coking closed decoking device relates to the field of waste gas treatment of petrochemical coking devices, the coking closed decoking device comprises a coke tower, a coke chute, a coke tank and a sedimentation tank which are arranged in sequence, the coke tank and the sedimentation tank are both arranged in a closed shed, one side of the closed shed is provided with a loading shed, and the other side of the closed shed is provided with a discharge port. The full-automatic intelligent anti-explosion coke grabbing travelling crane arranged in the closed shed can move above the coke storage tank, the sedimentation tank and the loading shed, the loading shed is separated from the closed shed through a partition, an airflow uniform distributor is arranged on the partition, the loading shed is provided with a collecting fan, and the collecting fan is connected with the closed shed. Gas in the car loading shed is collected by a collecting fan and then is fed into the closed shed through a gas flow uniform distributor; a plurality of circulating fans are respectively arranged on the ceiling and the side wall of the closed shed, and the blowing direction of the circulating fans faces the working area of the full-automatic intelligent anti-explosion coke grabbing travelling crane. According to the utility model, the technical problems that a full-automatic intelligent anti-explosion coke grabbing travelling crane is easy to corrode and low in decoking efficiency can be solved.

Description

Technical Field

[0001] The utility model relates to the field of waste gas treatment of a petrochemical coking device, in particular to a waste gas collection and treatment system for a coking closed decoking device. Background Art

[0002] Petroleum coke goes through the processes of decoking, dehydration, coking, transportation, storage and loading in the coking unit. During this process, volatile organic compounds, malodorous gases and petroleum coke dust are produced, which cause serious pollution to the environment.

[0003] At present, the conventional practice for a closed decoking device using a crane scheme is to place the coke storage tank and sedimentation tank of the coking device in a closed warehouse, connect the exhaust gas liquid separation pretreatment device and the exhaust gas washing absorption tower to the coke tower and the closed warehouse, and remove water vapor from the exhaust gas in the coking device through the exhaust gas liquid separation pretreatment device, thereby reducing the ambient humidity in the coking device, alleviating the processing load of the exhaust gas washing absorption tower, and improving the purification treatment effect of the exhaust gas.

[0004] However, after actual operation, the applicant found that the following problems still exist in the prior art: 1. The gas pretreated by the waste gas liquid separation pretreatment device returns to the top of the sealed warehouse, and the relatively dry and clean gas gathers at the top. The gas in the lower part of the sealed warehouse that has not been sucked into the waste gas liquid separation pretreatment device still contains a lot of water vapor and dust. The gas containing a lot of water and dust is not easy to flow to the roof due to its own density and gravity, causing pollutants such as dust and water vapor to gather and stay in the closed shed. On the one hand, it affects the monitoring line of sight and makes it difficult to accurately confirm the position of the fully automatic intelligent explosion-proof coke grabbing crane and coke, causing production delays or affecting the decoking efficiency. On the other hand, it is easy to cause corrosion of the fully automatic intelligent explosion-proof coke grabbing crane and the equipment in the closed warehouse; 2. The gas treated by the waste gas washing and absorption tower contains VOCs. The prior art sends this gas to the inlet of the heating furnace blower in the factory as the heating furnace air supply combustion to remove VOCs, and finally achieves standard emission of waste gas. However, when the waste gas cannot be sent to the heating furnace in an emergency, the VOCs in it will be directly discharged, causing air pollution. Utility Model Content

[0005] The utility model aims to provide an exhaust gas collection and treatment system for a coking closed decoking device, so as to solve the technical problems of easy corrosion of the fully automatic intelligent explosion-proof coking crane and low decoking efficiency.

[0006] In order to solve the above technical problems, the specific solution adopted by the utility model is as follows: a waste gas collection and treatment system for a coking closed decoking device, the coking closed decoking device includes a coke tower, a coke chute, a coke pool and a sedimentation tank arranged in sequence, the coke pool and the sedimentation tank are both arranged in a closed shed, the coke tower and the closed shed are connected to the liquid separation pretreatment device through a first collecting hood, the gas treated by the liquid separation pretreatment device is returned to the closed shed, the closed shed is connected to the waste gas washing and desulfurization tower through a second collecting hood, and a loading shed is provided on one side of the closed shed. The loading shed has a loading space below the enclosed shed, and the fully automatic intelligent explosion-proof coke grabbing crane arranged in the enclosed shed can move above the coke storage tank, sedimentation tank and loading space. The loading shed is separated from the enclosed shed by a partition, and the partition is provided with an air flow uniformizer. The loading shed is provided with a collecting fan, and the gas in the loading shed is collected by the collecting fan and then sent into the enclosed shed through the air flow uniformizer; the ceiling and side walls of the enclosed shed are respectively provided with a plurality of circulation fans, and the blowing direction of the circulation fan is toward the working area of the fully automatic intelligent explosion-proof coke grabbing crane.

[0007] As a further optimization of the above technical solution, a circulating gas pipeline is provided in the loading shed, the air inlet end of the circulating gas pipeline is located at the exhaust gas collection point at the top of the loading space, the collection fan is located on the circulating gas pipeline, and the exhaust end of the circulating gas pipeline is connected to the air flow distributor.

[0008] As a further optimization of the above technical solution, the circulation fan located on the ceiling of the enclosed shed is an explosion-proof industrial ceiling fan, and the circulation fan located on the side wall of the enclosed shed is an explosion-proof industrial floor fan.

[0009] As a further optimization of the above technical solution, the roof of the enclosed shed is provided with an automatically opening skylight, and a combustible and toxic gas detector is installed in the enclosed shed.

[0010] As a further optimization of the above technical solution, there are multiple first collecting hoods, which are respectively located at the top of the coke tower, the coke outlet of the coke chute and the steam discharge port above the sedimentation tank; there are multiple second collecting hoods, which are respectively located at the top of the sedimentation tank and the top of the closed shed, and the exhaust pipe of the liquid separation pretreatment device is connected to the top of the closed shed.

[0011] As a further optimization of the above technical solution, the coke tower and the closed shed are connected to the liquid separation pretreatment device through a first air inlet pipeline, and a plurality of first bypasses are provided on the first air inlet pipeline, and each first bypass is respectively connected to a first collecting hood; the closed shed is connected to the exhaust gas washing and desulfurization tower through a second air inlet pipeline, and a plurality of second bypasses are provided on the second air inlet pipeline, and each second bypass is respectively connected to a second collecting hood.

[0012] As a further optimization of the above technical solution, the exhaust pipe of the waste gas washing and desulfurization tower is divided into a first exhaust branch and a second exhaust branch. The first exhaust branch is connected to the heating furnace fan inlet, and a VOCs remover is provided on the second exhaust branch.

[0013] As a further optimization of the above technical solution, the exhaust pipe of the VOCs remover is connected to the first exhaust branch, two exhaust branches are provided at the end of the first exhaust branch, and each exhaust branch is provided with a pneumatic butterfly valve, one of the exhaust branches is connected to the inlet of the heating furnace fan, and the other exhaust branch is used for exhaust gas emission that meets the standards.

[0014] As a further optimization of the above technical solution, a combustible and toxic gas detector is provided on the exhaust pipe of the waste gas washing and desulfurization tower. The combustible and toxic gas detector is interlocked with the pneumatic butterfly valve provided on the first exhaust branch, the pneumatic butterfly valve provided on the second exhaust branch, the pneumatic butterfly valve provided on the exhaust pipe of the VOCs remover, and the pneumatic butterfly valves provided on the two exhaust branches at the end of the second exhaust branch.

[0015] As a further optimization of the above technical solution, the bottoms of the exhaust gas washing and desulfurization tower, VOCs remover, and liquid separation pretreatment device are all connected to the coke pool through the main sewage pipe.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1. By installing facilities such as circulating fans and air flow equalizers, the air in the closed shed can be guaranteed to flow evenly, preventing dust, water vapor and other pollutants from gathering and staying in the closed shed and affecting the line of sight during decoking, thereby improving decoking efficiency. The flow of air can also reduce the adhesion of water vapor and dust on the equipment in the closed shed, reducing the risk of equipment corrosion. By installing an air flow equalizer on the partition between the closed shed and the loading shed, the gas in the loading shed is collected and evenly sent into the closed shed. The collection fan, air flow equalizer, liquid separation pretreatment device, circulating fan and other equipment together form an air circulation system, which helps the air circulation and heat exchange in the closed shed.

[0018] 2. After dust removal and water vapor removal, the exhaust gas is desulfurized in an exhaust gas scrubber and desulfurization tower. It is then sent to the inlet of the heating furnace blower in the factory as the heating furnace air supply for combustion and removal of VOCs, ultimately achieving standard exhaust gas emissions. A VOCs remover is installed at the end of the exhaust gas treatment system. In emergency situations where the exhaust gas cannot be sent to the heating furnace, this device can still quickly remove VOCs and achieve standard exhaust gas emissions.

[0019] 3. A combustible and toxic gas detector is installed on the exhaust pipe of the waste gas washing and desulfurization tower. The combustible and toxic gas detector is interlocked with the corresponding pneumatic butterfly valve. When the combustible and toxic gas detection in the exhaust gas at the outlet of the waste gas washing and desulfurization tower exceeds the design limit of the closed decoking process, the pneumatic butterfly valve on the exhaust pipe is interlocked to cut off the exhaust gas pipe at the inlet of the decoking device heating furnace blower, and switch the exhaust gas to the VOCs remover to quickly remove VOCs and directly meet the emission standards, avoiding direct emission of VOCs-containing gas discharged from the waste gas washing and desulfurization tower, causing environmental pollution.

[0020] 4. An automatically opening skylight is installed on the top of the enclosed shed, which can realize the emptying of the enclosed shed in an emergency and prevent the accumulation of harmful gases to reach a critical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the system flow of the utility model;

[0022] Figure numerals: 1, coke tower, 2, coke chute, 3, coke pool, 4, sedimentation tank, 5, closed shed, 6, loading shed, 601, loading space, 7, fully automatic intelligent explosion-proof coke grabbing crane, 8, lower hopper, 9, circulation fan, 10, collection cover, 101, first collection cover, 102, second collection cover, 11, pneumatic butterfly valve, 12, collection fan, 13, gas flow detector, 14, air flow uniformizer, 15, liquid separation pretreatment device, 16, cooling spray head, 17, high-efficiency demister, 18, circulation fan, 19, basket filter, 20, circulation washing water pump, 21, washing water cooler, 22, pneumatic regulating valve, 2 3. Liquid flow detector, 24. Liquid level detection, 25. Temperature detection, 26. Exhaust gas washing and desulfurization tower, 27. Alkali washing spray head, 28. Secondary demister, 29. Circulating absorption pump, 30. VOCs remover, 31. Combustible and toxic gas detector, 32. Booster fan, 33. Sewage main pipe, 34. Second exhaust pipeline, 3401. First exhaust branch, 3402. Second exhaust branch, 35. First air intake pipeline, 36. Second air intake pipeline, 37. First exhaust pipeline, 38. Circulating gas pipeline, 39. Partition, 3901. First vertical section, 3902. Horizontal section, 3903. Second vertical section. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further elaborated in detail below in conjunction with the accompanying drawings and specific embodiments. The parts that are not recorded and disclosed in detail in the following embodiments of the present invention, such as the interlocking control of the automatic opening of the skylight and the combustible and toxic gas detector, the installation and operation of the fully automatic intelligent explosion-proof coke grabbing crane in the closed shed, the specific structure of the liquid separation pretreatment device, the exhaust gas washing and desulfurization tower and the VOCs remover, the combustible and toxic gas detector, the pneumatic butterfly valve, and the installation method of the pneumatic regulating valve on the corresponding pipeline should be understood as the existing technology known or should be known to those skilled in the art.

[0024] like Figure 1 As shown, the utility model discloses a waste gas collection and treatment system for a coking closed decoking device, the coking closed decoking device includes a coke tower 1, a coke chute 2, a coke pool 3 and a sedimentation tank 4 arranged in sequence, the coke pool 3 and the sedimentation tank 4 are both arranged in a closed shed 5, the coke tower 1 and the closed shed 5 are both connected with a liquid separation pretreatment device 15, so as to transport the waste gas with high water vapor and dust content in the coke tower 1 and the closed shed 5 to the liquid separation pretreatment device 15, and the gas treated by the liquid separation pretreatment device 15 can be returned to the closed shed 5, and the closed shed 5 is also connected with an exhaust gas washing and desulfurization tower 26, so as to desulfurize and purify the exhaust gas in the closed shed 5 and discharge it. The waste gas in the coke tower 1 and the closed shed 5 is pretreated by the liquid separation pretreatment device 15 to remove dust and water vapor in the waste gas. The gas treated by the liquid separation pretreatment device 15 is returned to the closed shed 5, which can reduce the ambient humidity in the closed shed 5 and reduce the processing load of the subsequent waste gas washing and desulfurization tower 26.

[0025] A loading shed 6 is provided on one side of the enclosed shed 5. The enclosed shed 5 and the loading shed 6 are separated by a partition 39. An air flow distributor 14 is provided on the partition 39. A collecting fan 12 is provided in the loading shed 6. The gas in the loading shed 6 is collected by the collecting fan 12 and then sent into the enclosed shed 5 through the air flow distributor 14.

[0026] The loading shed 6 has a loading space 601 located below the enclosed shed 5 and an exit (not shown) for coke transport vehicles to enter and exit. The loading shed 6 and the enclosed shed 5 both include side walls and a ceiling. The partition 39 serves as part of the side walls of the loading shed 6 and the enclosed shed 5. The ceiling height of the loading shed 6 is lower than that of the enclosed shed 5. Figure 1As shown, the partition 39 includes a first vertical section 3901, a horizontal section 3902, and a second vertical section 3903 connected sequentially from bottom to top. The lower end of the first vertical section 3901 is connected to the upper edge of the side wall of the sedimentation tank 4, and the horizontal section 3902 extends to a side away from the sedimentation tank 4. The airflow distributor 14 is disposed in the second vertical section 3903. The outer wall of the sedimentation tank 4, the first vertical section 3901, and the horizontal section 3902 form the loading space 601. It is understandable that the lower end of the first vertical section 3901 can also be disposed on the ground, as long as the sedimentation tank 4 is located within the enclosed shed 5.

[0027] A hopper 8 is provided in the horizontal section 3902, and a fully automatic intelligent explosion-proof coke grabbing crane 7 is installed in the enclosed shed 5. The fully automatic intelligent explosion-proof coke grabbing crane 7 is located above the coke storage tank 3, sedimentation tank 4, and loading position 601 of the loading shed 6, and is able to move above the coke storage tank 3, sedimentation tank 4, and loading position 601. After the coke transport car enters the loading position 601 of the loading shed 6, it can align with the hopper 8. When the coke drum 1 begins decoking, the coke falls from the coke chute 2 at the bottom of the coke drum 1 into the coke tank 3. The fully automatic intelligent explosion-proof coke grabbing crane 7 grabs the coke, drains it, and then moves it to the hopper 8 of the loading shed 6, where it is loaded into the coke transport car.

[0028] The amount of gas released by the coke on the coke transport car is large, so an exhaust gas collection point is provided at the top of the loading station 601. The exhaust gas collection point is equipped with a collection hood to effectively collect the gas released by the coke on the coke transport car. A circulating gas pipeline 38 is provided in the loading shed 6. The air inlet end of the circulating gas pipeline 38 is connected to the exhaust gas collection point at the top of the loading station 601. The collection fan 12 is located on the circulating gas pipeline 38, and the exhaust end of the circulating gas pipeline 38 is connected to the air flow distributor 14. The gas in the loading shed is collected by the air flow distributor 14 and evenly sent into the closed shed 5. The collection fan 12, air flow distributor 14, liquid separation pretreatment device 16, circulation fan 18, circulation fan 9 and other equipment together form an air circulation system to facilitate air circulation and heat exchange in the closed shed 5. In addition, the gas in the closed shed 5 is transported to the liquid separation pretreatment device 15 or the exhaust gas washing and desulfurization tower 26, and can also undergo corresponding moisture removal or purification treatment.

[0029] It should be noted that the fully automatic intelligent explosion-proof coke grabbing crane 7 is a modified explosion-proof intelligent crane from a non-explosion-proof crane. It can be remotely operated manually and automatically, eliminating the need for personnel to enter the enclosed shed 5. A video monitor is installed within the enclosed shed 5 for remote operation of the explosion-proof intelligent crane, a state-of-the-art technology. Combustible and toxic gas detectors are also installed within the enclosed shed 5 to monitor the environmental safety of the enclosed shed 5 at all times, ensuring the safety of personnel entering during equipment maintenance and inspection.

[0030] An automatically opening skylight is provided on the top of the enclosed shed 5, which can be emptied in an emergency to prevent harmful gases from accumulating to a critical value. The controller for controlling the automatic opening of the skylight is interlocked with the combustible and toxic gas detector in the enclosed shed 5. When the combustible and toxic gas detector detects that the toxic gas in the enclosed shed 5 exceeds the standard, the combustible and toxic gas detector can transmit a signal to the controller, which controls the automatic opening of the skylight to activate and empty the enclosed shed 5 in an emergency. The specific control process program setting, the automatic opening of the skylight, and the structure of the combustible and toxic gas detector are all existing technologies and will not be repeated here.

[0031] The top and surrounding protection of the enclosed shed 5 adopt a combination of anti-corrosion corrugated plates + fiberglass skylights, which can effectively extend the service life of the enclosure and reduce the corrosion of water-containing exhaust gas.

[0032] Multiple circulation fans 9 are installed on the ceiling and side walls of the enclosed shed 5. These fans 9 blow air toward the working area of the fully automatic, intelligent, explosion-proof coke grabbing crane 7. The fans on the ceiling are large-diameter, industrial explosion-proof ceiling fans, while those on the side walls are industrial explosion-proof floor fans. The presence of these fans ensures uniform and rapid air flow within the enclosed shed 5, preventing water vapor from accumulating in the center of the shed, which could affect the crane's line of sight and exhaust gas collection. These fans also reduce the adhesion of water vapor and dust to the fully automatic, intelligent, explosion-proof coke grabbing crane 7 and other equipment within the shed, lowering humidity within the shed 5 to a certain extent and thus minimizing the risk of equipment corrosion.

[0033] Multiple exhaust gas collection points are provided within the coke drum 1 and the enclosed shed 5, each equipped with a collection hood 10. The collection hood 10 includes multiple first collection hoods 101 connected to the liquid separation pretreatment device 15 via a pipeline, and multiple second collection hoods 102 connected to the exhaust gas scrubbing and desulfurization tower 26. The coke drum 1 and the enclosed shed 5 are connected to the liquid separation pretreatment device 15 via a first air inlet pipeline 35. The first air inlet pipeline 35 is provided with multiple first bypasses, each of which is connected to a corresponding first collection hood 101. The enclosed shed 5 is connected to the exhaust gas scrubbing and desulfurization tower 26 via a second air inlet pipeline 36. The second air inlet pipeline 36 is provided with multiple second bypasses, each of which is connected to a corresponding second collection hood 102.

[0034] In this embodiment, there are three first collecting hoods 101, which are respectively located at the steam discharge port at the top of the coke tower, the outlet of the coke chute, and the top of the sedimentation tank. The liquid separation pretreatment device 15 is connected to the coke tower 1 and the closed shed 5 through the first air inlet pipeline 35. Three first bypasses are provided on the first air inlet pipeline 35, and each first bypass is connected to a first collecting hood 101. The first bypass connected to the first collecting hood 101 at the steam discharge port at the top of the sedimentation tank is provided with a pneumatic butterfly valve 11 and a gas flow detector 13; the first bypass connected to the first collecting hood 101 at the coke outlet of the coke chute is provided with a pneumatic butterfly valve 11, a collecting fan 12 and a gas flow detector 13. Similarly, the first bypass connected to the first collecting hood 101 at the top of the coke tower 1 is also provided with a pneumatic butterfly valve 11, a collecting fan 12 and a gas flow detector 13. The gas processed by the liquid separation pre-treatment device 15 is connected to the inside of the closed shed 5 through the first exhaust pipeline 36 and is located at the top of the closed shed 5. A circulation fan 18 is provided on the first exhaust pipeline 36.

[0035] The air circulation system is composed of the circulation fan 9, the collection fan 12, the collection cover 10, the waste gas liquid separation pretreatment device 15, the circulation fan 18, the air flow uniformizer 13 and the corresponding air intake and exhaust ducts. This ensures that the air in the closed shed 5 flows evenly, prevents pollutants such as dust and water vapor from gathering and staying in the closed shed 5, which would affect the line of sight during decoking, and reduces the humidity in the closed shed 5, thereby reducing the risk of equipment corrosion.

[0036] Multiple second collection hoods 102 connected to the exhaust gas scrubber and desulfurization tower 26 are located within the enclosed shed 5. In this embodiment, there are two second collection hoods 102 within the enclosed shed 5, one located at the top of the sedimentation tank and the other at the top of the enclosed shed. The exhaust gas scrubber and desulfurization tower 26 is connected to the enclosed shed 5 via an air inlet pipeline. The air inlet pipeline of the exhaust gas scrubber and desulfurization tower 26 is a second air inlet pipeline 36. The second air inlet pipeline 36 is divided into two second bypasses, each of which is connected to a second collection hood 102. In addition, the exhaust gas scrubber and desulfurization tower 26 is connected to a second collection hood (not shown) located in the cold tar water tank area to transport exhaust gas from the cold tar water tank area to the exhaust gas scrubber and desulfurization tower 26 for treatment. The second air inlet pipeline 36 is connected to an auxiliary air inlet pipe, which is connected to the second collection hood in the cold tar water tank area. The auxiliary air inlet pipe is equipped with a pneumatic butterfly valve 11 and a collection fan 12.

[0037] A gas transmission pipeline is connected between the first exhaust pipe 37 and the second air intake pipe 36 and a pneumatic butterfly valve 11 is provided. When the amount of gas discharged from the liquid separation pretreatment device 15 is small or the amount of waste gas to be treated by the waste gas washing and desulfurization tower 26 is insufficient, the pneumatic butterfly valve 11 can be opened to directly transport the gas discharged from the liquid separation pretreatment device 15 to the second air intake pipe 36, and then enter the waste gas washing and desulfurization tower 26 for treatment, without returning the gas to the closed shed 5 before outputting it.

[0038] The liquid separation pretreatment device 15 adopts a two-stage structure, equipped with a cooling spray head 16 and a high-efficiency demister 17 from bottom to top. The water-containing waste gas in the enclosed shed 5 (located at the top of the coke drum, the outlet of the coke chute, and the steam vent above the coke pool) is collected by a first water-containing waste gas collection hood 101. It is then collected by a collection fan 12 through a pipeline and converged to a single point before entering the liquid separation pretreatment device 15. At the bottom of the liquid separation pretreatment device 15, it is sprayed with washing water to remove coke fines and cool the waste gas. After being sprayed with washing water, the waste gas falls to the bottom of the liquid separation pretreatment device 15. The waste gas enters the high-efficiency demister 17 at the top of the liquid separation pretreatment device 15 to remove droplets, and is then transported back to the enclosed shed 5 via a circulating fan 18. The washing water at the bottom of the liquid separation pretreatment device 15 is pumped out by a circulating washing water pump 20, first filtered through a basket filter 19 to remove coke fines, then cooled by a washing water cooler 21, and then returned to the liquid separation pretreatment device 15 for recycling. It should be noted that the washing water can be low-temperature coke water, coke cutting water or other room temperature water, and the circulating washing water pump 20 is a corrosion-resistant and wear-resistant single-stage centrifugal pump. The washing water cooler 21 is a plate or shell and tube heat exchanger.

[0039] The cooling water usage of the wash water cooler 21 is controlled by a temperature sensor 25 on the exhaust gas outlet pipe (i.e., first exhaust pipe 37) of the liquid separation pretreatment device 15. The wash water circulation rate is controlled and regulated by a liquid flow sensor 23 and a pneumatic control valve 22 on the inlet pipe of the cooling spray head 16. The liquid level at the bottom of the liquid separation pretreatment device 15 is controlled and regulated by a liquid level sensor 24 and a pneumatic control valve 22 on the outlet pipe of the circulating wash water pump 20.

[0040] The exhaust gas scrubbing and desulfurization tower 26 adopts a two-stage structure, with an alkaline cleaning spray head 27 at the bottom and a high-efficiency demister 17 and a secondary demister 28 at the top. The alkaline cleaning liquid can be 10-30% sodium hydroxide solution, amine solution or other alkaline desulfurization agents.

[0041] The dry exhaust gas within the enclosed shed 5 is collected by the second collection hood 102, then converges through the corresponding second bypass to the second air inlet line 36 and enters the exhaust gas scrubber and desulfurization tower 26. At the bottom of the exhaust gas scrubber and desulfurization tower 26, it passes through the alkaline spray nozzle 27 to remove hydrogen sulfide and mercaptans from the exhaust gas. After the alkaline spray, the absorption liquid falls into the bottom of the exhaust gas scrubber and desulfurization tower 26. The exhaust gas enters the high-efficiency demister 17 at the top of the exhaust gas scrubber and desulfurization tower 26 to remove water droplets. It then passes through the secondary demister 28 to further remove droplets and prevent alkaline liquid carryover. After desulfurization, the exhaust gas is then sent to the coking unit heating furnace blower inlet via the booster fan 32, where it participates in the heating furnace air supply combustion to remove VOCs and meet emission standards. The absorption liquid at the bottom of the exhaust gas scrubber and desulfurization tower 26 is pumped out by the circulating absorption pump 29, first filtered through the basket filter 19 to remove excess dust and salt crystals, and then returned to the exhaust gas scrubber and desulfurization tower 26 for recycling.

[0042] The circulation volume of the alkaline cleaning liquid is controlled and regulated by the liquid flow detector 23 and the pneumatic regulating valve 22 on the inlet pipe of the alkaline cleaning spray head 27.

[0043] The liquid outlet pipe of the circulating absorption pump 29 is divided into two liquid outlet branches. One of the liquid outlet branches is connected to the alkali cleaning spray head 27 as its inlet pipe, and the other liquid outlet branch is connected to the lean liquid outlet device. A pneumatic control valve 22 is installed on the liquid outlet branch connected to the lean liquid outlet device. The liquid supply pipe that supplies absorption liquid to the exhaust gas scrubber and desulfurization tower 26 is connected to the liquid outlet pipe of the exhaust gas scrubber and desulfurization tower 26 and is located upstream of the basket filter 19. The liquid supply pipe is connected to the pneumatic control valve 22. The liquid level sensor 24 on the exhaust gas scrubber and desulfurization tower 26 is interlocked with the pneumatic control valve 22 installed on the liquid outlet branch connected to the lean liquid outlet device and the pneumatic control valve 22 connected to the liquid supply pipe.

[0044] The exhaust pipe of the exhaust gas washing and desulfurization tower 26 is the second exhaust pipe 34. The second exhaust pipe 34 is divided into a first exhaust branch 3401 and a second exhaust branch 3402. The first exhaust branch 3401 is connected to the inlet of the heating furnace fan, and the second exhaust branch 3402 is provided with a VOCs remover 30. The exhaust pipe of the VOCs remover 30 is connected to the first exhaust branch 3401. The booster fan 32 is provided on the first exhaust branch 3401 and is located downstream of the exhaust pipe of the VOCs remover 30. Two exhaust branches are provided at the end of the first exhaust branch 3401, and each exhaust branch is provided with a pneumatic butterfly valve 11. One of the exhaust branches is connected to the inlet of the heating furnace fan, and the other exhaust branch is used to provide exhaust gas that meets the standards.

[0045] A combustible and toxic gas detector 31 is provided on the exhaust pipe of the waste gas washing and desulfurization tower 26. The combustible and toxic gas detector 31 is interlocked with the pneumatic butterfly valve 11 provided on the first exhaust branch 3401, the pneumatic butterfly valve 11 provided on the second exhaust branch 3402, the pneumatic butterfly valve 11 provided on the exhaust pipe of the VOCs remover 30, and the pneumatic butterfly valves 11 provided on the two exhaust branches at the end of the second exhaust branch 3402. When the combustible and toxic gas content detected by the combustible and toxic gas detector 31 in the exhaust gas at the outlet of the waste gas washing and desulfurization tower 26 exceeds the design limit of the closed decoking process, the interlocking pneumatic butterfly valve 11 on the exhaust pipe cuts off the exhaust gas pipeline at the inlet of the decoking device heating furnace blower, and switches the exhaust gas to the VOCs remover 30 to quickly remove VOCs so that the exhaust gas meets the emission standards directly. Specifically, by closing the pneumatic butterfly valve 11 on the first exhaust branch 3401 and the pneumatic butterfly valve 11 connected to the exhaust branch connected to the heating furnace fan inlet, the exhaust gas can be switched to the VOC remover 30 and discharged after VOC removal. The present utility model provides two methods for treating VOC-containing exhaust gas. Depending on the actual situation, it can be sent to the heating furnace fan inlet for heating and combustion treatment, or it can be removed by the VOC remover 30. This can maintain the normal operation of the system and avoid the emission of VOC-containing gases and pollution.

[0046] The air inlet pipe of the exhaust gas washing and desulfurization tower 26 is provided with an interlockingly controlled combustible and toxic gas detector 31 and a pneumatic butterfly valve 11. At the same time, the combustible and toxic gas detector 31 provided on the air inlet pipe is interlocked and controlled with the electrical equipment in the closed shed 5. When the combustible and toxic gas content detected by the combustible and toxic gas detector 31 exceeds the design limit of the closed decoking process, the electrical equipment in the closed shed 5 is interlocked and shut down.

[0047] It should be noted that the collection fan 12 in this invention utilizes an axial flow fan or a single-stage centrifugal fan, with flow-through components made of wear-resistant and corrosion-resistant materials and a drainage system at the bottom. The circulation fan 18 and booster fan 32 utilize single-stage high-pressure centrifugal fans, with flow-through components made of wear-resistant and corrosion-resistant materials and a drainage system at the bottom. The fan flow rate is regulated by a variable frequency motor.

[0048] The bottoms of the exhaust gas scrubbing and desulfurization tower 26, the VOCs remover 30, and the liquid separation pretreatment device 15 are all connected to the coke pool 3 via a main sewage pipe 33. Specifically, a sewage pipe connected to the main sewage pipe 33 is provided at the bottom of the VOCs remover 30. The liquid flow detector 23 on the VOCs remover 30 is interlocked with the pneumatic control valve 22 on the sewage pipe to promptly discharge the waste generated after the VOCs remover 30 removes the exhaust gas. The bottoms of the liquid separation pretreatment device 15 and the exhaust gas scrubbing and desulfurization tower 26 are both provided with a drainage pipe, connected to a basket filter 19. Impurities filtered by the basket filter 19 are connected to the main sewage pipe 33 through the drainage pipe. Among them, the liquid outlet pipe of the liquid after filtering by the basket filter 19 of the liquid separation pretreatment device 15 is divided into two liquid outlet branches after passing through the circulating washing water pump 20, one of which is connected to the cooling spray head 16 as the liquid inlet pipe of the cooling spray head 16, and the other liquid outlet branch is provided with a pneumatic regulating valve 22 and connected to the sewage main pipe 33. When the liquid level detection 24 of the liquid separation pretreatment device 15 detects that the liquid level of the liquid separation pretreatment device 15 reaches a certain level, the pneumatic regulating valve 22 on the liquid outlet branch can be controlled to discharge the liquid in the liquid separation pretreatment device 15 from the liquid outlet branch to the sewage main pipe 33.

[0049] The enclosed decoking waste gas collection and treatment system of the coking device of the present invention can solve the problem that the water vapor content in the enclosed shed 5 is too high, which affects the decoking line of sight and causes production delays; when an emergency occurs in the heating furnace, it can not affect the normal operation of the waste gas collection and treatment system; when an emergency occurs in the enclosed shed 5, it can empty the waste gas.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A waste gas collection and treatment system for a coking closed decoking device, wherein the coking closed decoking device comprises a coke drum (1), a coke chute (2), a coke pool (3) and a sedimentation tank (4) arranged in sequence, wherein the coke pool (3) and the sedimentation tank (4) are both arranged in a closed shed (5), and the coke drum (1) and the closed shed (5) are both connected to a liquid separation pretreatment device (15) through a first collecting hood (101), and the gas treated by the liquid separation pretreatment device (15) is returned to the waste gas collection system. To the enclosed shed (5), the enclosed shed (5) is connected to the exhaust gas washing and desulfurization tower (26) through the second collecting hood (102), a loading shed (6) is provided on one side of the enclosed shed (5), the loading shed (6) has a loading position (601) located below the enclosed shed (5), and a fully automatic intelligent explosion-proof coke grabbing crane (7) provided in the enclosed shed (5) can move above the coke storage tank (3), the sedimentation tank (4) and the loading position (601), characterized in that: The loading shed (6) is separated from the enclosed shed (5) by a partition (39), and an air flow distributor (14) is provided on the partition (39). The loading shed (6) is provided with a collecting fan (12). The gas in the loading shed (6) is collected by the collecting fan (12) and then sent to the enclosed shed (5) through the air flow distributor (14); the ceiling and side walls of the enclosed shed (5) are respectively provided with a plurality of circulation fans (9), and the blowing direction of the circulation fans (9) is toward the working area of the fully automatic intelligent explosion-proof coke grabbing crane (7).

2. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 1, characterized in that: A circulating gas pipeline (38) is provided in the loading shed (6), the air inlet end of the circulating gas pipeline (38) is located at the exhaust gas collection point on the top of the loading space (601), the collection fan (12) is located on the circulating gas pipeline (38), and the exhaust end of the circulating gas pipeline (38) is connected to the air flow distributor (14).

3. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 1, characterized in that: The circulation fan (9) located on the ceiling of the enclosed shed (5) is an explosion-proof industrial ceiling fan, and the circulation fan (9) located on the side wall of the enclosed shed (5) is an explosion-proof industrial floor fan.

4. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 1, characterized in that: The roof of the enclosed shed (5) is provided with an automatically opening skylight, and a combustible and toxic gas detector (31) is provided inside the enclosed shed (5).

5. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 1, characterized in that: The first collecting hoods (101) are multiple in number and are respectively located at the top of the coke tower (1), the coke outlet of the coke chute (2) and the steam discharge port above the sedimentation tank (4); the second collecting hoods (102) are multiple in number and are respectively located at the top of the sedimentation tank (4) and the top of the closed shed (5), and the exhaust pipe of the liquid separation pretreatment device (15) is connected to the top of the closed shed (5).

6. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 5, characterized in that: The coke tower (1) and the closed shed (5) are connected to the liquid separation pretreatment device (15) via a first air inlet pipeline (35), and a plurality of first bypasses are provided on the first air inlet pipeline (35), and each first bypass is respectively connected to a first collecting hood (101); the closed shed (5) is connected to the exhaust gas washing and desulfurization tower (26) via a second air inlet pipeline (36), and a plurality of second bypasses are provided on the second air inlet pipeline (36), and each second bypass is respectively connected to a second collecting hood (102).

7. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 1, characterized in that: The exhaust pipe of the waste gas washing and desulfurization tower (26) is divided into a first exhaust branch (3401) and a second exhaust branch (3402). The first exhaust branch (3401) is connected to the inlet of the heating furnace fan, and the second exhaust branch (3402) is provided with a VOCs remover (30).

8. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 7, characterized in that: The exhaust pipe of the VOCs remover (30) is connected to the first exhaust branch (3401). Two exhaust branches are provided at the end of the first exhaust branch (3401), and each exhaust branch is provided with a pneumatic butterfly valve (11). One of the exhaust branches is connected to the inlet of the heating furnace fan, and the other exhaust branch is used for exhaust gas that meets the standards.

9. The exhaust gas collection and treatment system for a coking closed decoking device according to claim 7, characterized in that: A combustible and toxic gas detector (31) is provided on the exhaust pipe of the waste gas washing and desulfurization tower (26). The combustible and toxic gas detector (31) is interlocked with a pneumatic butterfly valve (11) provided on the first exhaust branch (3401), a pneumatic butterfly valve (11) provided on the second exhaust branch (3402), a pneumatic butterfly valve (11) provided on the exhaust pipe of the VOCs remover (30), and a pneumatic butterfly valve (11) provided on the two exhaust branches at the end of the second exhaust branch (3402).

10. The exhaust gas collection and treatment system for a coking closed decoking device according to any one of claims 7 to 9, characterized in that: The bottoms of the waste gas washing and desulfurization tower (26), the VOCs remover (30), and the liquid separation pretreatment device (15) are all connected to the coke pool (3) through the sewage main pipe (33).

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