Waste gas treatment equipment for semi-coke discharging and waste gas treatment method of waste gas treatment equipment

Abstract

The invention relates to the technical field of pollution treatment in semi-coke production, and discloses waste gas treatment equipment and a waste gas treatment method for semi-coke coke discharge. The equipment comprises a sealing cover system, a waste gas collection system and a waste gas pretreatment system. The sealing cover system forms a sealing environment through a conveying cover and a flexible sealing piece. The waste gas collecting system collects waste gas through a plurality of air suction branch pipes with air volume adjusting valves and a main air pipe. The pretreatment system sequentially comprises a static pressure box, a cyclone dust collector, a conveying fan, a multi-stage washing tower unit, a demister and an activated carbon adsorption device. The invention further provides a corresponding waste gas treatment method. The method comprises the steps of sealed collection, air volume calculation, waste gas pretreatment, monitoring and recycling and the like. Pollutants such as dust, tar, ammonia gas and VOCs in the waste gas are effectively removed through a multi-stage purification process, the standard waste gas can be recycled to the carbonization furnace to serve as combustion-supporting air, and efficient purification treatment and resource utilization of the waste gas are achieved.

Description

Technical Field

[0001] This invention relates to the field of pollution treatment in semi-coke production, and more specifically, to a waste gas treatment device and a waste gas treatment method for semi-coke coking. Background Technology

[0002] Semi-coke is a new type of carbon material made from high-quality Jurassic coal blocks from the Shenfu Coalfield. It has the characteristics of high fixed carbon content, high resistivity, high chemical activity, and low ash, aluminum, sulfur, and phosphorus content. It has gradually replaced metallurgical coke and is widely used in the production of products such as calcium carbide, ferroalloys, ferrosilicon, and silicon carbide.

[0003] The production of semi-coke inevitably generates a large amount of air pollutants, mainly including semi-coke dust, volatile organic compounds (VOCs), carbon monoxide, ammonia, and other odorous gases. These pollutants primarily originate from fugitive emissions during the semi-coke conveyor belt process, volatilization and evaporation during wastewater storage and treatment, emissions during abnormal operating conditions (such as start-up, shutdown, and maintenance), and accidental emissions. Especially in critical areas such as the coke discharge conveyor belt, ammonia tank area, tar tank area, and emergency water pool, the concentrations of pollutants such as non-methane hydrocarbons, ammonia, benzene, and naphthalene in the exhaust gas are high, resulting in severe odors at the production site and significantly impacting the surrounding environment and human health.

[0004] At present, the dust and exhaust gas treatment technologies of coke production enterprises are relatively mature. They usually use a gas collection system to collect exhaust gas, and then pre-treat it through physical or chemical methods such as water washing, oil washing, acid washing, and alkali washing. Finally, the exhaust gas is transported to the coke oven for combustion or to achieve standard emissions through a fan.

[0005] However, due to the high content of non-methane total hydrocarbons, ammonia, benzene, naphthalene, and other pollutants in the waste gas generated during the semi-coke production process, such as in the coke conveyor belt, ammonia tank area, tar tank area, and emergency water pool, the production site has a serious odor. Traditional waste gas treatment technologies are difficult to achieve the goal of deep purification of dust and waste gas in one step, or cannot meet national and local emission control standards, thus restricting the further development of enterprises. Summary of the Invention

[0006] The purpose of this invention is to provide a waste gas treatment device for semi-coke coking.

[0007] Another objective of this invention is to provide a waste gas treatment method for a waste gas treatment device.

[0008] A waste gas treatment device for semi-coke coking, comprising:

[0009] A sealing cover system is used to enclose the coke discharge belt conveyor area. The sealing cover system includes a belt conveyor, a conveyor cover sleeved above the belt conveyor, and a flexible sealing element disposed between the conveyor cover and the belt conveyor to form a sealed environment on the belt conveyor.

[0010] The exhaust gas collection system, connected to the sealing cover system, is used to draw in and transport high-concentration exhaust gas. The exhaust gas collection system includes multiple spaced suction branch pipes arranged on the conveying cover, each suction branch pipe is equipped with an air volume regulating valve, and a main air pipe connected to the multiple suction branch pipes.

[0011] The exhaust gas pretreatment system is connected to the main duct and includes, along the airflow direction, the following components in sequence:

[0012] A static pressure chamber is used to mix high- and low-concentration waste gases;

[0013] Cyclone dust collectors are used to remove large dust particles;

[0014] Conveyor fan;

[0015] Multi-stage scrubbing tower unit for removing tar, ammonia and fine particulate matter;

[0016] Demister;

[0017] Activated carbon adsorption devices are used to further purify volatile organic compounds (VOCs).

[0018] Furthermore, it also includes a recycle combustion system, which transports the pretreated waste gas to the carbonization furnace through a recycle pipeline to serve as combustion air for high-temperature decomposition.

[0019] Furthermore, the flexible seal is a rubber skirt.

[0020] Furthermore, the total air volume design of the exhaust gas collection system is based on a calculation model of the leakage area of ​​the sealing cover, and the calculation model of the leakage area is as follows: Where Q is the airflow rate, VP is the set pressure difference, and A is the total air leakage area.

[0021] Preferably, the leakage area calculation model also includes: Where (4005) is the conversion factor; V is the velocity, in feet per minute; VP is the pressure difference, in inches of water column; A is the total air leakage area, in square feet; and Q is the air flow rate, in cubic feet per minute.

[0022] Furthermore, the multi-stage scrubbing tower unit includes a single-stage gravity spray tower and at least three-stage packed spray towers.

[0023] Furthermore, the main air duct and / or the return furnace duct are equipped with a combustible gas concentration monitor for real-time monitoring of the combustible gas concentration in the exhaust gas.

[0024] Furthermore, the return pipeline is equipped with a control valve, and the opening degree of the control valve is adjusted according to the combustible gas concentration monitored by the combustible gas concentration monitor.

[0025] Furthermore, the conveying fan is a variable frequency fan, which can adjust the operating frequency according to changes in system resistance.

[0026] Furthermore, the activated carbon adsorption device adopts a drawer-type structure, which facilitates the replacement of activated carbon packing.

[0027] A waste gas treatment method using a waste gas treatment device includes the following steps:

[0028] S1: Sealing and collecting step, the belt conveyor area during the semi-coke coking process is sealed by a sealing cover system to form a negative pressure sealed environment, wherein the flexible sealing element is in close contact with the belt conveyor to effectively prevent the leakage of waste gas, and an exhaust vent is set on the conveyor cover every 2 to 3 m, and the exhaust vent is connected to the suction branch pipe.

[0029] S2: The system airflow is calculated using the air leakage area calculation model. When the average gap between the conveyor hood and the belt conveyor is 2cm wide, the belt length of the belt conveyor is 53m, and the air leakage area at the end of the conveyor hood is approximately 1.0m * 0.2m; therefore, the total air leakage area is A = 2.34m². 2 Under these conditions, the average intake air velocity at the leaky surface is 4.08 m / s, the negative pressure inside the hood is approximately 10 Pa, and the total air volume required for the suction branch pipe is Q = 34428 m³ / s. 3 / h;

[0030] S3: Waste gas conveying and pretreatment steps: High-concentration waste gas is drawn out through multiple suction branch pipes in the waste gas collection system. The air volume regulating valve on each branch pipe adjusts the air volume according to the waste gas concentration distribution. The waste gas is conveyed to the pretreatment system through the main air duct and undergoes the following treatment in sequence.

[0031] The exhaust gas is mixed in a static pressure box in the exhaust gas pretreatment system, large dust particles are removed by a cyclone dust collector, tar, ammonia and fine particulate matter are removed by a multi-stage scrubbing tower unit, mist is removed by a demister, and volatile organic compounds (VOCs) are purified by an activated carbon adsorption device.

[0032] S4: Monitoring and Reuse Steps. The concentration of combustible gas in the main air duct and the return furnace pipeline is monitored in real time. When the concentration reaches the safety threshold, the pre-treated waste gas is transported to the carbonization furnace through the return furnace pipeline and used as combustion air for high-temperature decomposition treatment, so as to realize the resource utilization of waste gas.

[0033] Preferably, the pretreated waste gas is transported to the carbonization furnace through a return pipeline to be used as combustion air for high-temperature decomposition.

[0034] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0035] 1. By combining the sealing cover system with flexible sealing elements (such as rubber skirts), an effective negative pressure sealing environment is formed in the belt conveyor area, which greatly reduces the fugitive emission of exhaust gas, ensures the collection efficiency of high-concentration exhaust gas, and controls pollution at the source.

[0036] 2. The exhaust gas collection system adopts a scientific design based on the leakage area calculation model, and achieves precise air distribution through the air volume regulating valves on each suction branch pipe, ensuring that the system air volume matches the actual needs, which not only meets the collection effect, but also avoids energy waste.

[0037] 3. The pretreatment system integrates multiple processes such as physical dust removal (cyclone dust collector), chemical washing (multi-stage washing tower unit, including gravity spray and packed spray), demisting and adsorption (activated carbon), which can efficiently and hierarchically remove large particulate dust, tar, ammonia, fine particulate matter and VOCs and other pollutants from the exhaust gas, with thorough treatment and high purification efficiency. Attached Figure Description

[0038] Figure 1 This is a schematic diagram showing the connection between the sealing cover system and the exhaust gas collection system of the present invention;

[0039] Figure 2 This is a front view of the waste gas treatment equipment for semi-coke coking according to the present invention;

[0040] Figure 3 This is a schematic diagram of the overall process of the waste gas treatment equipment for semi-coke coking of the present invention.

[0041] Figure 4 This is an enlarged schematic diagram of invention A;

[0042] Figure 5 This is a schematic diagram of the internal structure of the cyclone dust collector of the present invention;

[0043] in:

[0044] 1. Belt conveyor; 2. Conveyor cover; 3. Flexible seal; 4. Suction branch pipe; 5. Air volume regulating valve;

[0045] 6. Main air duct; 7. Static pressure box; 8. Cyclone dust collector; 9. Conveyor fan; 10. Multi-stage scrubbing tower unit;

[0046] 11. Demister; 12. Activated carbon adsorption device; 13. Return furnace pipeline; 14. Carbonization furnace. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this application. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments without creative effort are within the scope of protection of this application.

[0048] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0049] Example 1

[0050] like Figure 1-5 The present embodiment discloses a waste gas treatment device for semi-coke coking.

[0051] A waste gas treatment device for semi-coke coking, comprising:

[0052] A sealing cover system is used to enclose the coke discharge belt conveyor area. The sealing cover system includes a belt conveyor 1, a conveyor cover 2 sleeved on the belt conveyor 1, and a flexible sealing element 3 disposed between the conveyor cover 2 and the belt conveyor 1 to form a sealed environment on the belt conveyor 1.

[0053] The exhaust gas collection system, connected to the sealing cover system, is used to draw in and transport high-concentration exhaust gas. The exhaust gas collection system includes multiple spaced suction branch pipes 4 arranged on the conveying cover 2, each suction branch pipe 4 is equipped with an air volume regulating valve 5, and a main air pipe 6 connected to the multiple suction branch pipes 4.

[0054] The exhaust gas pretreatment system is connected to the main duct 6. The exhaust gas pretreatment system includes, in sequence along the airflow direction:

[0055] Static pressure box 7 is used to mix high and low concentration waste gases;

[0056] Cyclone dust collector 8 is used to remove large dust particles;

[0057] Conveyor fan 9;

[0058] Multi-stage scrubbing tower unit 10 is used to remove tar, ammonia and fine particulate matter;

[0059] Demister 11;

[0060] Activated carbon adsorption device 12 is used for further purification of volatile organic compounds (VOCs).

[0061] It also includes a recycle combustion system, which transports the pretreated waste gas to the carbonization furnace 14 through the recycle pipe 13 as combustion air for high-temperature decomposition.

[0062] The flexible seal 3 is a rubber skirt.

[0063] Specifically, when the work begins, the sealing cover 2 system is activated first when the exhaust gas generated during the coking process of semi-coke needs to be transported through the belt conveyor 1. The flexible sealing element 3 (such as a rubber skirt) between the sealing cover installed above the belt conveyor 1 and the belt conveyor forms an effective seal, creating a relatively closed environment in the conveying area to prevent the unorganized diffusion of exhaust gas.

[0064] The exhaust gas collection system then begins operation. Multiple suction branch pipes 4, mounted on the conveyor hood, adjust the suction air volume according to the differences in exhaust gas concentration in each area, controlled by the airflow regulating valve 5. This is achieved through a calculation model based on the leakage area. With its scientific design, the system can precisely control the total air volume, ensuring that exhaust gas is collected with the best efficiency.

[0065] The collected high-concentration waste gas is transported to the waste gas pretreatment system through the main air duct 6. The waste gas first enters the static pressure box 7. During this process, the high-concentration and low-concentration waste gas are fully mixed to provide a uniform waste gas composition for subsequent treatment.

[0066] The mixed exhaust gas enters the cyclone dust collector 8, where large dust particles are removed by centrifugal force, reducing the load on subsequent processing units.

[0067] The exhaust gas that has undergone preliminary dust removal enters the multi-stage scrubbing tower unit 10 under the power of the conveying fan 9. The multi-stage scrubbing tower unit 10 gradually removes tar, ammonia and fine particulate matter from the exhaust gas through multi-stage scrubbing.

[0068] After washing, the wet exhaust gas passes through the demister 11 to remove the water mist and droplets it carries, forming relatively dry exhaust gas to ensure the normal operation of subsequent treatment units;

[0069] The relatively dry exhaust gas then enters the activated carbon adsorption device 12, which adopts a drawer-type structure design to facilitate the replacement of activated carbon packing; during this process, volatile organic compounds (VOCs) are adsorbed and purified by activated carbon.

[0070] Throughout the entire process, the system monitors the changes in the composition of the exhaust gas in real time. When the concentration of combustible gas reaches the safety threshold, the control valve on the return pipeline 13 is automatically opened, and the pre-treated exhaust gas is transported to the carbonization furnace 14.

[0071] Finally, the pretreated exhaust gas is used as combustion air in the carbonization furnace 14 for high-temperature decomposition. The residual organic pollutants are completely decomposed in the high-temperature environment inside the furnace, realizing the resource utilization and final treatment of the exhaust gas.

[0072] Throughout the system's operation, the various processing units work collaboratively, and the entire process is monitored and adjusted through an automated control system to ensure stable and efficient processing, thus solving both the problem of exhaust gas pollution and realizing the recovery and utilization of energy.

[0073] As one embodiment, the total air volume design of the exhaust gas collection system is based on a calculation model of the leakage area of ​​the sealing cover, wherein the leakage area calculation model is as follows: Where Q is the airflow rate, VP is the set pressure difference, and A is the total air leakage area.

[0074] The air leakage area calculation model also includes: VP=(V / 4005)^2, V=Q / A, VP=(Q / 4005A)^2, where (4005) is the conversion factor; V is the velocity, unit: feet / minute; VP is the pressure difference, unit: inches of water column; A is the total air leakage area, unit: square feet; Q is the air flow rate, unit: cubic feet / minute.

[0075] Specifically, when the high-concentration waste gas generated during the semi-coke coking process needs to be transported via belt conveyor 1, the sealing hood system is activated first. The flexible sealing element 3 (using a rubber skirt) between the conveyor hood 2, which is fitted above the belt conveyor 1, and the belt conveyor 1 forms an effective seal. According to the engineering design, when the average width of the gap between the conveyor hood 2 and the belt conveyor 2 is 2cm, the belt length is 53m, and the air leakage surface size at the end of the conveyor hood is 1.0m × 0.2m, the total air leakage area of ​​the system is calculated to be A = 2.34m². 2 A stable negative pressure collection system is formed in this sealed environment.

[0076] Then the exhaust gas collection system starts working, based on the leakage area calculation model. System airflow design was performed; under the condition of a negative pressure of 10 Pa inside the hood, the average inlet air velocity at the leakage surface was calculated to be 4.08 m / s, and the total airflow required for the suction branch pipe 4 was Q = 34428 m³ / s.3 / h. Multiple spaced suction branch pipes 4 installed on the conveyor hood 2 adjust the suction volume in real time according to the difference in exhaust gas concentration in each area under the precise control of the air volume regulating valve 5.

[0077] The collected exhaust gas is then transported to the pretreatment system through the main duct 6 for concentration homogenization, providing stable intake conditions for subsequent processes.

[0078] As one embodiment, the multi-stage scrubbing tower unit 10 includes a single-stage gravity spray tower and at least three-stage packed spray towers.

[0079] Specifically, the dust-treated exhaust gas enters the multi-stage scrubbing tower unit 10 under the power of the conveying fan 9. This unit includes a first-stage gravity spray tower and at least three-stage packed spray towers. Through the multi-stage scrubbing process, tar, ammonia and fine particulate matter in the exhaust gas are gradually removed by physical absorption and chemical reaction.

[0080] Specifically, the pre-treated waste gas enters the three-stage packed spray tower system in sequence; the first-stage packed tower uses alkaline absorbent liquid (such as NaOH solution), which increases the gas-liquid contact area through the packing layer, effectively absorbing acidic gases such as ammonia in the waste gas, with a removal rate of over 85%.

[0081] The second-stage packed tower uses an organic solvent absorbent specifically designed to dissolve and absorb tar components in the waste gas. The packing material features an anti-clogging design to ensure long-term stable operation, achieving a tar removal efficiency of over 90%.

[0082] The third-stage packed tower employs a fine atomization spray system, generating micron-sized droplets through specially designed nozzles to effectively capture fine particulate matter in the exhaust gas. This stage is also equipped with a high-efficiency demister to prevent droplet entrainment, achieving a fine particulate matter removal efficiency of over 95%.

[0083] Specifically, the multi-stage scrubbing tower unit 10 is also equipped with an automatic dosing system and an online pH monitor to adjust the concentration and pH value of the absorbent in real time to ensure the best treatment effect; each stage of the tower is equipped with an inspection port and an observation window for easy daily maintenance and operation monitoring; the entire system is made of corrosion-resistant materials to ensure long-term stable operation of the equipment.

[0084] As one embodiment, a combustible gas concentration monitor is installed on the main air duct 6 and / or the return furnace pipe 13 to monitor the concentration of combustible gas in the exhaust gas in real time.

[0085] The return pipeline 13 is equipped with a control valve, and the opening degree of the control valve is adjusted according to the combustible gas concentration monitored by the combustible gas concentration monitor.

[0086] Specifically, the present invention is equipped with an advanced combustible gas concentration monitoring system on key pipelines. Specifically, infrared combustible gas concentration monitors are installed at the air inlet end of the main air duct 6 and the outlet end of the return furnace pipe 13. These monitors adopt the non-contact measurement principle and accurately determine the volume concentration of combustible gases such as methane and carbon monoxide in the exhaust gas by detecting infrared absorption of specific wavelengths.

[0087] The monitor on the main air duct 6 mainly serves as an early warning device, issuing an early warning signal when the concentration of combustible gas exceeds 20% of the lower explosive limit; the monitor on the recycle pipe 13 serves as the main basis for safety control, and its monitoring data is directly transmitted to the staff to ensure that the data is real-time and accurate.

[0088] Specifically, an electric regulating valve is installed on the recycle pipe 13 as a control valve. This valve is made of high-temperature and corrosion-resistant materials and equipped with an intelligent positioner. Based on the data transmitted by the combustible gas concentration monitor, the valve opening is adjusted manually by the staff or automatically by the control system: when the concentration is between 5-15% LEL, the valve is opened to 30-50%; when the concentration is between 15-25% LEL, it is opened to 50-80%; and when the concentration exceeds 25% LEL, the valve is immediately closed.

[0089] Example 2

[0090] like Figure 1-5 As shown, this embodiment discloses a waste gas treatment device for semi-coke coking, which is similar in technical solution to Embodiment 1, except that:

[0091] As one embodiment, the conveying fan 9 is a variable frequency fan, which can adjust the operating frequency according to changes in system resistance.

[0092] Specifically, the variable frequency fan of the present invention uses an explosion-proof three-phase asynchronous motor as the power source. The motor protection level reaches IP55, the insulation level is F, and it has overheat protection and overload protection functions to ensure safe operation in flammable and explosive environments.

[0093] The impeller of the conveyor fan 9 adopts a backward-curved centrifugal impeller design and is made of high-strength aluminum alloy. The impeller and the motor shaft are connected by a tapered sleeve and reinforced with a keyway to ensure transmission reliability and installation accuracy.

[0094] The inlet of the conveyor fan 9 is equipped with an adjustable air guide device made of stainless steel, which can adjust the air inlet angle according to system requirements; the casing adopts a double-layer steel plate structure with sound-absorbing material in the middle, effectively reducing the operating noise to below 85 decibels.

[0095] As one embodiment, the activated carbon adsorption device 12 adopts a drawer-type structure, which facilitates the replacement of activated carbon packing.

[0096] Specifically, the activated carbon adsorption device 12 of the present invention adopts a modular drawer-type structure design. Each adsorption unit is equipped with an independent sealed drawer compartment. The compartment is made of 304 stainless steel and has multiple sets of activated carbon packing layers inside. The drawer unit is equipped with a guide rail system and a quick locking device, which can realize the replacement operation by a single person. Each drawer unit is equipped with an observation window and a handle for easy daily inspection and use.

[0097] The activated carbon packing uses a combination of honeycomb activated carbon and granular activated carbon. The upper layer uses honeycomb activated carbon with a pore size of 3mm, and the lower layer is filled with 4-6mm granular activated carbon, forming a hierarchical adsorption structure. This design can effectively increase the gas-solid contact area, improve adsorption efficiency, and reduce system resistance, achieving a VOCs removal efficiency of over 95%.

[0098] Example 3

[0099] like Figure 1-5 As shown in the embodiment, an exhaust gas treatment method of an exhaust gas treatment device is disclosed, including the following steps:

[0100] S1: Sealing and collecting step, the belt conveyor area during the semi-coke coking process is sealed by the sealing cover system to form a negative pressure sealing environment. The flexible sealing element 3 is in close contact with the belt conveyor 1 to effectively prevent the leakage of waste gas. An exhaust vent is set on the conveyor cover 2 every 2 to 3 m, and the exhaust vent is connected to the suction branch pipe 4.

[0101] S2: The system air volume is calculated using the air leakage area calculation model. When the average gap between the conveyor hood 2 and the belt conveyor 1 is 2cm wide, the belt length of the belt conveyor 1 is 53m, and the air leakage surface size at the end of the conveyor hood 2 is approximately 1.0m * 0.2m; therefore, the total air leakage area is A = 2.34m2; under this condition, the average air intake velocity at the air leakage surface is 4.08m / s, the negative pressure inside the hood is approximately 10pa, and the total air volume required for the suction branch pipe 4 is Q = 34428m3 / h;

[0102] S3: Waste gas conveying and pretreatment steps: High-concentration waste gas is drawn out through multiple suction branch pipes in the waste gas collection system. The air volume regulating valve on each branch pipe adjusts the air volume according to the waste gas concentration distribution. The waste gas is conveyed to the pretreatment system through the main air duct and undergoes the following treatment in sequence.

[0103] The exhaust gas is mixed in the static pressure box 7 of the exhaust gas pretreatment system, large dust particles are removed by the cyclone dust collector 8, tar, ammonia and fine particulate matter are removed by the multi-stage scrubbing tower unit 10, mist is removed by the demister 11, and volatile organic compounds (VOCs) are purified by the activated carbon adsorption device 12.

[0104] S4: Monitoring and reuse steps: Real-time monitoring of the concentration of combustible gas in the main air duct 6 and the return furnace pipe 13. When the concentration reaches the safety threshold, the pre-treated waste gas is transported to the carbonization furnace 14 through the return furnace pipe 13 and used as combustion air for high-temperature decomposition treatment to realize the resource utilization of waste gas.

[0105] Specifically, the pretreated waste gas is transported to the carbonization furnace 14 through the return pipe 13 as combustion air for high-temperature decomposition.

[0106] The waste gas treatment method provided by this invention forms a complete process for treating semi-coke coke exhaust gas through steps such as sealed collection, scientific air volume calculation, multi-stage purification treatment, and real-time monitoring and reuse. It effectively realizes the whole-process purification treatment and resource utilization of waste gas, and has significant advantages such as high treatment efficiency, safe and reliable operation, and high energy recovery and utilization rate.

[0107] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A waste gas treatment apparatus for coke oven gas of green coke, characterized by, The invention relates to a coke discharge system, which comprises: a sealing cover system for sealing the coke discharge belt conveying area, the sealing cover system comprising a belt conveyor (1), a conveying cover (2) arranged above the belt conveyor (1), and a flexible sealing element (3) arranged between the conveying cover (2) and the belt conveyor (1) to form a sealed environment on the belt conveyor (1); an exhaust gas collection system connected to the sealing cover system for sucking and conveying high-concentration exhaust gas, the exhaust gas collection system comprising a plurality of spaced exhaust branch pipes (4) arranged on the conveying cover (2), each exhaust branch pipe (4) being provided with an air volume regulating valve (5), and a main air pipe (6) connected to the plurality of exhaust branch pipes (4); an exhaust gas pretreatment system connected to the main air pipe (6), the exhaust gas pretreatment system comprising, in sequence along the airflow direction: a static pressure tank (7) for mixing high and low concentration exhaust gas; a cyclone dust collector (8) for removing large particle dust; a conveying fan (9); a multi-stage washing tower unit (10) for removing tar, ammonia and fine particulate matter; a mist eliminator (11); and an activated carbon adsorption device (12) for further purifying volatile organic compounds (VOCs).

2. The waste gas treatment apparatus for green coke pushing according to claim 1, wherein The invention also relates to a recycling combustion system, which conveys the pretreated exhaust gas to a carbonization furnace (14) through a recycling pipeline (13) as combustion air for high-temperature decomposition.

3. The waste gas treatment apparatus for green coke pushing according to claim 1, wherein The flexible sealing element (3) is a rubber skirt.

4. The waste gas treatment apparatus for green coke pushing according to claim 1, wherein The total air volume design of the exhaust gas collection system is based on a sealing cover air leakage area calculation model, and the air leakage area calculation model is: Wherein, Q is air flow, VP is set pressure difference, and A is total air leakage area.

5. The waste gas treatment apparatus for green coke pushing according to claim 1, wherein The multi-stage washing tower unit (10) comprises a primary gravity spray tower and at least three stages of packed spray towers.

6. The waste gas treatment apparatus for green coke pushing according to claim 1, wherein The main air pipe (6) and / or the recycling pipeline (13) is provided with a combustible gas concentration monitor for real-time monitoring of the combustible gas concentration in the exhaust gas.

7. The off-gas treatment apparatus for green coke pushing according to claim 6, characterized by, The recycling pipeline (13) is provided with a control valve, and the opening degree of the control valve is adjusted according to the combustible gas concentration monitored by the combustible gas concentration monitor.

8. The off-gas treatment apparatus for the green coke pushing according to claim 1, characterized by, The conveying fan (9) is a variable frequency fan, which can adjust the operating frequency according to the change of system resistance.

9. The off-gas treatment apparatus for the green coke pushing according to claim 1, characterized by, The activated carbon adsorption device (12) adopts a drawer type structure, which is convenient for replacing the activated carbon filler.

10. An exhaust gas treatment method using the exhaust gas treatment apparatus according to any one of claims 4, characterized by, The invention also relates to a coke discharge method, which comprises the following steps: S1: sealing and collecting step, the belt conveying area during the coke discharging process is sealed by the sealing cover system to form a negative pressure sealed environment, wherein the flexible sealing element (3) is in close contact with the belt conveyor (1) to effectively prevent exhaust gas leakage, and one air suction port is arranged every 2-3 m on the conveying cover (2), and the air suction port is connected to the exhaust branch pipe (4); S2: calculate the system air volume by the air leakage area calculation model, when the average gap between the conveying cover (2) and the belt conveyor (1) is 2 cm wide, the belt length of the belt conveyor (1) is 53 m, the air leakage surface size of the conveying cover (2) end is about 1.0 m*0.2 m; therefore the total air leakage area is A=2.34 m 2 ; in this case, the average air inlet speed of the air leakage surface is 4.08 m / s, the negative pressure in the cover is about 10 pa, and the total air volume required for the air suction branch pipe (4) is Q=34428 m 3 / h; S3: exhaust gas conveying and pretreatment step, high-concentration exhaust gas is sucked by the plurality of exhaust branch pipes in the exhaust gas collection system, the air volume regulating valve on each branch pipe adjusts the air volume according to the exhaust gas concentration distribution, and the exhaust gas is conveyed to the pretreatment system through the main air pipe and is sequentially subjected to the following treatments: the exhaust gas is sequentially mixed by the static pressure tank (7) in the exhaust gas pretreatment system, large particle dust is removed by the cyclone dust collector (8), tar, ammonia and fine particulate matter are removed by the multi-stage washing tower unit (10), mist is removed by the mist eliminator (11), and volatile organic compounds (VOCs) are purified by the activated carbon adsorption device (12). S4: monitoring and recycling step, real-time monitoring of the concentration of combustible gas in the main air pipe (6) and the recycling pipeline (13), when the concentration reaches the safety threshold, the pretreated waste gas is transported to the carbonization furnace (14) through the recycling pipeline (13) as combustion air for high-temperature decomposition treatment, realizing the resource utilization of waste gas.

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