A combined desulfurization system and method for dry quenching furnace emission gas and dust removal emission gas

Abstract

The present application relates to the technical field of flue gas purification, and specifically discloses a dry quenching furnace diffused flue gas and dust removal flue gas combined desulfurization system and method, which comprises a pre-storage chamber diffused flue gas pipeline, a primary desulfurization unit, a pre-storage chamber side bag-type dust collector, a pre-storage chamber side dust removal booster fan, a main body dust removal flue gas pipeline, a total mixed reaction pipeline, a secondary desulfurization unit, a rear-end bag-type dust collector, a rear-end dust removal booster fan and a chimney; the primary and secondary desulfurization units are respectively provided with a desulfurizer bin, a rotary feeder and a gas-material mixing device; the pre-storage chamber diffused flue gas is mixed with the main body dust removal flue gas after primary desulfurization and secondary desulfurization, and the two rotary feeders are controlled by an interlocking control cabinet; the present application adopts a hierarchical desulfurization architecture, is suitable for two types of flue gas working conditions, and improves the desulfurization operation stability.

Description

Technical Field

[0001] This invention relates to the field of flue gas purification technology, specifically to a combined desulfurization system and method for dry quenching furnace venting flue gas and dust removal flue gas. Background Technology

[0002] The dry quenching coke production process mainly generates two types of sulfur-containing flue gas with significantly different physical properties: the flue gas from the dry quenching furnace body dust collector and the flue gas from the pre-storage chamber. The flue gas from the dry quenching furnace body dust collector is characterized by low temperature, low sulfur, and large intermittent fluctuations in air volume; while the flue gas from the pre-storage chamber is characterized by high temperature, high sulfur, and stable flow rate. The two types of flue gas have significantly different operating parameters and different requirements for the adaptability of desulfurization treatment.

[0003] The existing methods for desulfurizing dry quenching flue gas mainly employ two approaches: separate treatment or unified mixed treatment, both of which have significant technical defects. First, traditional branch treatment processes have dispersed equipment layouts and numerous discharge outlets, making overall operation and maintenance management difficult. The limestone-gypsum wet desulfurization process used for flue gas venting in the pre-storage chamber has problems such as easy slurry poisoning, strong equipment corrosion, high energy consumption, high operating costs, and poor system stability.

[0004] Second, the traditional mixed desulfurization process combines two types of flue gas and then performs unified dry desulfurization. Ordinary calcium hydroxide dry desulfurization is insufficient for treating high-concentration sulfur-containing flue gas, and sulfur dioxide emissions are prone to exceed the standard under high-sulfur conditions. Sodium bicarbonate dry desulfurization has strict requirements on flue gas temperature. After mixing, the flue gas temperature is difficult to meet the reaction conditions, resulting in a significant decrease in desulfurization effect. In addition, the generated sodium-based desulfurization ash solid waste is difficult to dispose of and has high treatment costs.

[0005] The purpose of this invention is to provide a combined desulfurization system and method for dry quenching furnace venting gas and dust removal flue gas to solve the problems mentioned in the background art. Summary of the Invention

[0006] To achieve the above objectives, the present invention provides a combined desulfurization system for venting flue gas and dust removal flue gas from a dry quenching furnace, comprising a pre-storage chamber venting flue gas pipeline, a primary desulfurization unit, a pre-storage chamber side bag filter, a pre-storage chamber side dust removal booster fan, a main body dust removal flue gas pipeline, a total mixing reaction pipeline, a secondary desulfurization unit, a rear-end bag filter, a rear-end dust removal booster fan, and a chimney; The primary desulfurization unit is located on the flue gas venting pipeline of the pre-storage chamber. The primary desulfurization unit includes a first desulfurizing agent silo, a first rotary feeder, a first gas-material mixing device, and a static mixing reactor. The outlet of the first desulfurizing agent silo is connected to the inlet of the first rotary feeder, the outlet of the first rotary feeder is connected to the first gas-material mixing device, the output end of the first gas-material mixing device is connected to the static mixing reactor, and the static mixing reactor is connected in series on the flue gas venting pipeline of the pre-storage chamber. The flue gas venting pipeline of the pre-storage chamber passes sequentially through the primary desulfurization unit, the bag filter on the pre-storage chamber side, and the dust removal booster fan on the pre-storage chamber side before connecting to the main mixing reaction pipeline. The dust removal flue gas pipeline is directly connected to the main mixing reaction pipeline; The secondary desulfurization unit is arranged on the main mixing reaction pipeline. The secondary desulfurization unit includes a second desulfurizing agent silo, a second rotary feeder, and a second gas-material mixing device. The outlet of the second desulfurizing agent silo is connected to the inlet of the second rotary feeder, the outlet of the second rotary feeder is connected to the second gas-material mixing device, and the output end of the second gas-material mixing device is connected to the main mixing reaction pipeline. The outlet of the main mixing reaction pipeline is connected to the rear bag filter, the rear bag filter is connected to the rear dust removal booster fan, and the outlet of the rear dust removal booster fan is connected to the chimney. It also includes an interlocking control cabinet, which is connected to the control signals of the first rotary feeder and the second rotary feeder respectively; By setting up a graded structure of independent desulfurization of dual flue gas and mixed deep desulfurization, the two types of flue gas in the dry quenching furnace are desulfurized in a coordinated and efficient manner, which greatly improves the overall flue gas purification effect.

[0007] As a further improvement of the present invention, a connecting pipeline and a shut-off valve are provided between the supply pipelines of the first desulfurizing agent silo and the second desulfurizing agent silo, and the connecting pipeline is connected to the discharge end of the first gas-material mixing device and the second gas-material mixing device. By connecting two sets of desulfurizing agent supply pipelines for mutual backup, system shutdown is avoided due to single-line supply failure, thus improving the continuity and operational stability of desulfurization supply.

[0008] As a further improvement of the present invention, it also includes a bypass pipeline, one end of which is connected to the discharge end pipeline of the static mixing reactor, and the other end is connected to the main mixing reaction pipeline. An bypass valve is provided on the bypass pipeline. Isolation valves are provided at the air inlet end of the bag filter on the pre-storage chamber side and the air outlet end of the dust collector booster fan on the pre-storage chamber side. By adding bypass pipelines and corresponding isolation valves, bypass ventilation can be provided when the bag filter or the dust collector booster fan on the pre-storage chamber side is under maintenance, enabling system maintenance without shutting down the system and effectively improving the convenience of equipment operation and maintenance and the fault tolerance of the system.

[0009] As a further improvement of the present invention, it also includes a fluidizing gas supply pipeline and a fluidizing blower; the fluidizing gas supply pipeline is equipped with two gas inlets, which are connected in parallel to the inlet of the fluidizing blower, one of which is connected to the exhaust outlet of the flue gas purified by the dust removal booster blower at the rear end, and the other is connected to the exhaust outlet of the booster blower after coke oven dust removal and purification; the outlet of the fluidizing blower is provided with two fluidizing branch pipes for the silo body, which are respectively connected to the fluidizing plate inlets of the first desulfurizing agent silo and the second desulfurizing agent silo; A dual-path purified flue gas intake is adopted as the fluidized gas source to realize the resource utilization of waste flue gas.

[0010] As a further improvement of the present invention, each fluidized branch pipe of the silo is provided with a spare external fluidizing gas source branch in parallel; each fluidized branch pipe of the silo is also provided with a straight branch pipe, and the two straight branch pipes are respectively connected to the first gas-material mixing device and the second gas-material mixing device. By configuring a backup external fluidizing gas source and a gas-material mixing direct branch pipe, continuous material supply can be ensured in the event of a gas source failure, while also enhancing the gas-material mixing effect and improving the desulfurization reaction efficiency.

[0011] As a further improvement of the present invention, it also includes multiple sets of flue gas analysis instruments; The pre-storage chamber venting flue gas pipeline is located in the upstream section of the primary desulfurization unit and is equipped with the first online flue gas analyzer and the first flow meter. The main dust removal flue gas pipeline is located upstream of the secondary desulfurization unit and is equipped with a second online flue gas analyzer and a second flow meter. A third online flue gas analyzer is installed on the outlet pipe section of the dust removal booster fan on the pre-storage chamber side. The chimney exhaust pipe section is equipped with a fourth online flue gas analyzer; The first flue gas online analyzer, the first flow meter, the second flue gas online analyzer, the second flow meter, the third flue gas online analyzer, and the fourth flue gas online analyzer are all electrically connected to the interlocking control cabinet. By collecting flue gas parameters in real time from multiple online flue gas analyzers, data support is provided for precise automatic desulfurization, ensuring the closed-loop controllable operation of the system.

[0012] A method for combined desulfurization of flue gas from a dry quenching furnace and flue gas from dust removal includes the following steps: S1. Collect the flue gas released from the pre-storage chamber of the dry quenching furnace. The first flue gas online analyzer and the first flow meter collect the sulfur dioxide concentration and flow parameters of the pre-storage flue gas in real time. Based on the collected concentration and flow parameters, match the corresponding calcium hydroxide desulfurizing agent dosage. The first rotary feeder outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is transported to the static mixing reactor through the first gas-material mixing device and fully mixed with the flue gas released from the pre-storage chamber to complete the initial dry desulfurization. The initial desulfurization flue gas flows sequentially through the bag filter on the pre-storage chamber side and the dust removal booster fan on the pre-storage chamber side before being sent into the main mixing reaction pipeline. S2. The dust removal flue gas from the dry quenching furnace body is sent into the main mixing reaction pipeline and mixed with the flue gas output from the dust removal booster fan on the pre-storage chamber side to form mixed flue gas. S3. The second flue gas online analyzer collects the sulfur dioxide concentration and flow parameters of the mixed flue gas. Based on the collected concentration and flow parameters, it matches the corresponding calcium hydroxide desulfurizing agent dosage. The second rotary feeder outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is sent into the total mixing reaction pipeline through the second gas-material mixing device to fully contact and react with the mixed flue gas, thus completing the secondary desulfurization. S4. The flue gas after secondary desulfurization is sent to the rear bag filter to remove dust. The flue gas after dust removal is pressurized by the rear dust removal booster fan and then sent to the chimney for external discharge. The fourth flue gas online analyzer monitors the sulfur dioxide emission concentration of the flue gas at the chimney outlet in real time. By combining primary desulfurization with secondary deep desulfurization in a step-by-step process, precise desulfurization of the two types of flue gas is achieved, ensuring stable and compliant emissions of the outlet flue gas.

[0013] As a further improvement of the present invention, the desulfurizing agent for the flue gas in the pre-storage chamber is automatically added in stages; the amount of desulfurizing agent added is controlled by a staged interlocking method according to the sulfur dioxide concentration of the flue gas in the pre-storage chamber of the dry quenching furnace before desulfurization: it is divided into several stages with intervals of 100mg / m³, each stage corresponding to a frequency value of the first rotary feeder. When the concentration reaches the corresponding stage range and lasts for 1 minute, the frequency of the first rotary feeder is automatically adjusted to the corresponding value of the stage. By controlling the first feeder through timed interlocking of sulfur dioxide concentration in the pre-stored flue gas, precise feeding of the initial desulfurization can be achieved, avoiding waste of reagents or insufficient desulfurization.

[0014] As a further improvement of the present invention, the mixed flue gas desulfurization adopts a composite parameter-based automatic control; the flue gas pollutant load value is obtained by multiplying the flue gas flow rate and sulfur dioxide concentration, and the multi-level composite control interval is divided with the load value of 100 as the dividing value. When the load value is stable in the same interval for 1 minute, the interlock control cabinet adjusts the operating frequency of the second rotary feeder according to the real-time collected concentration and flow parameters; when the sulfur dioxide concentration before desulfurization of the flue gas of the main dust collector is lower than 50 mg / m³ and lasts for 8-20 minutes, the addition of desulfurizing agent is suspended; wherein, the duration of this duration is set to be no less than one coking cycle, and the coking cycle is defined by the time from the start of coking in this furnace to the start of coking in the next furnace, wherein the start of coking is determined by the furnace cover opening signal. By adopting a combined load control method based on flow rate and concentration, and with the addition of a low-concentration suspension logic, the amount of secondary desulfurization chemicals used is matched with the real-time pollution load, achieving both desulfurization stability and energy saving.

[0015] As a further improvement of the present invention, the fluidizing fan is started during desulfurization operation, and two independent gas sources are selected to deliver airflow to the primary desulfurization unit and the secondary desulfurization unit. When the gas supply from the two gas sources is abnormal, the backup external fluidizing gas source branch is switched to supply gas. By employing a dual-gas-source selective fluidization and fault-based backup switching method, the continuous and stable fluidized delivery of desulfurizing agent is ensured, thereby improving the operational reliability of the entire desulfurization system.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention sets up a staged combined desulfurization process for two types of flue gas with significantly different characteristics, namely dry quenching and coke quenching. Through a segmented treatment method of primary desulfurization of flue gas released in a pre-storage chamber and secondary deep desulfurization of mixed flue gas, it achieves precise adaptation and treatment of flue gas under different operating conditions, effectively improving the overall desulfurization stability and flue gas compliance rate.

[0017] 2. This invention solves the operational risks caused by single-path supply failure and pipeline blockage by setting up a connecting pipeline between the supply pipelines of the first desulfurizing agent silo and the second desulfurizing agent silo, so that the two desulfurization supply units can serve as backups for each other, and greatly improves the continuous operation capability and fault tolerance of the system by setting up a connecting pipeline between the supply pipelines of the first desulfurizing agent silo and the second desulfurizing agent silo.

[0018] 3. In this invention, by configuring an overpass and isolation valve, the flue gas can bypass the bag filter or the dust collector booster fan on the pre-storage chamber side during maintenance, without the need for the entire production line to be shut down, thus reducing production losses.

[0019] 4. This invention utilizes the purified flue gas from the system as a fluidizing gas source to achieve waste heat utilization. With the addition of an external backup gas source branch, the gas source can be quickly switched in case of failure. At the same time, a straight branch pipe is set up to enhance gas-material mixing, which not only reduces gas supply energy consumption but also prevents powder blockage and bridging, thereby improving the fullness of the desulfurization reaction.

[0020] 5. This invention deploys a flue gas analysis instrument linkage and interlocking control cabinet throughout the entire process section, and sets differentiated control logic for two-stage desulfurization; pre-stored flue gas adopts single concentration level control, and mixed flue gas innovatively adopts flow rate and concentration composite pollution load level adjustment, and automatically stops the dosing of desulfurizing agents under low sulfur conditions, so as to achieve precise and on-demand addition of desulfurizing agents, significantly reduce agent consumption, and stably ensure that the outlet flue gas meets the standards. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a combined desulfurization system for dry quenching furnace vent gas and dust removal flue gas according to the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of a combined desulfurization system for dry quenching furnace vent gas and dust removal flue gas according to the present invention. Figure 2 .

[0022] In the diagram: 1. Smoke venting pipeline in the pre-storage room; 2. Primary desulfurization unit; 21. First desulfurizing agent silo; 22. First rotary feeder; 23. First gas-material mixing device; 24. Static mixing reactor; 3. Pre-storage chamber side bag filter; 4. Pre-storage chamber side dust removal booster fan; 5. Dust removal flue gas pipeline; 6. Main mixing and reaction pipeline; 7. Secondary desulfurization unit; 71. Second desulfurizing agent silo; 72. Second rotary feeder; 73. Second gas-material mixing device; 8. Rear-end bag filter; 9. Rear-end dust collector booster fan; 10. Chimney; 11. Connecting pipeline; 12. Shut-off valve; 13. Bypass pipeline; 14. Bypass valve; 15. Isolation valve; 16. Fluidized air supply pipeline; 161. Fluidized branch pipe of the silo; 162. External fluidized air supply branch pipe; 163. Straight branch pipe; 17. Fluidized blower; 18. First flue gas online analyzer; 181. First flow meter; 19. Second flue gas online analyzer; 191. Second flow meter; 20. Third flue gas online analyzer; 30. Fourth flue gas online analyzer. Detailed Implementation

[0023] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] The present invention will be further described in detail below with reference to the accompanying drawings.

[0027] refer to Figure 1A preferred embodiment of the present invention provides a combined desulfurization system for venting flue gas and dust removal flue gas from a dry quenching furnace, comprising a pre-storage chamber venting flue gas pipeline 1, a primary desulfurization unit 2, a pre-storage chamber side bag filter 3, a pre-storage chamber side dust removal booster fan 4, a main body dust removal flue gas pipeline 5, a total mixing reaction pipeline 6, a secondary desulfurization unit 7, a rear-end bag filter 8, a rear-end dust removal booster fan 9, and a chimney 10. The primary desulfurization unit 2 is installed on the flue gas venting pipeline 1 of the pre-storage chamber. The primary desulfurization unit 2 includes a first desulfurizing agent silo 21, a first rotary feeder 22, a first gas-material mixing device 23, and a static mixing reactor 24. The outlet of the first desulfurizing agent silo 21 is connected to the inlet of the first rotary feeder 22, the outlet of the first rotary feeder 22 is connected to the first gas-material mixing device 23, the output end of the first gas-material mixing device 23 is connected to the static mixing reactor 24, and the static mixing reactor 24 is connected in series on the flue gas venting pipeline 1 of the pre-storage chamber. The flue gas venting pipeline 1 passes sequentially through the primary desulfurization unit 2, the bag filter 3 on the pre-storage chamber side, and the dust removal booster fan 4 on the pre-storage chamber side before connecting to the main mixing reaction pipeline 6. The dust removal flue gas pipeline 5 is directly connected to the main mixing reaction pipeline 6; The secondary desulfurization unit 7 is arranged on the main mixing reaction pipeline 6. The secondary desulfurization unit 7 includes a second desulfurizing agent silo 71, a second rotary feeder 72, and a second gas-material mixing device 73. The outlet of the second desulfurizing agent silo 71 is connected to the inlet of the second rotary feeder 72, the outlet of the second rotary feeder 72 is connected to the second gas-material mixing device 73, and the output end of the second gas-material mixing device 73 is connected to the main mixing reaction pipeline 6. The outlet of the main mixing reaction pipeline 6 is connected to the rear bag filter 8, the rear bag filter 8 is connected to the rear dust removal booster fan 9, and the outlet of the rear dust removal booster fan 9 is connected to the chimney 10. It also includes an interlocking control cabinet, which is connected to the control signals of the first rotary feeder 22 and the second rotary feeder 72 respectively.

[0028] This invention's system employs a staged desulfurization architecture to address the two different types of flue gas generated during dry quenching. The pre-storage chamber's vented flue gas is high-concentration sulfur-containing gas, which first undergoes preliminary desulfurization treatment via primary desulfurization unit 2. Then, it merges with the low-concentration, highly fluctuating flue gas from the main dust collector, undergoing deep purification via secondary desulfurization unit 7. In this embodiment, highly active calcium hydroxide is selected as the desulfurizing agent to meet the requirements... With a content ≥90%, fineness (325 mesh sieve rate) ≥85%, BET specific surface area ≥40m² / g, and moisture content ≤2%, the calcium-based desulfurization system can avoid the drawbacks of sodium bicarbonate desulfurization process, such as high reaction temperature threshold and high cost of sodium-based solid waste disposal.

[0029] Optionally, such as Figure 1As shown, a connecting pipe 11 and a shut-off valve 12 are provided between the supply pipes of the first desulfurizing agent silo 21 and the second desulfurizing agent silo 71. The connecting pipe 11 is connected to the discharge end of the first gas-material mixing device 23 and the second gas-material mixing device 73.

[0030] In this embodiment, the two desulfurizing agent supply systems can communicate with each other through the connecting pipeline 11. Under normal production conditions, the shut-off valve 12 is closed, and the first desulfurizing agent silo 21 and the second desulfurizing agent silo 71 independently supply the primary desulfurization unit 2 and the secondary desulfurization unit 7, respectively. When either the rotary feeder or the silo auxiliary components need to be inspected or maintained, the shut-off valve 12 is opened, and the electric valve at the discharge end of the first gas-material mixing device 23 or the second gas-material mixing device 73 is closed. One of the supply units simultaneously delivers desulfurizing agent to both desulfurization units, ensuring that the entire desulfurization unit operates without interruption. Under this fault standby condition, the control system can switch to manual mode to adjust the feeding frequency.

[0031] Optionally, such as Figure 1 As shown, it also includes a bypass pipeline 13, one end of which is connected to the discharge end pipeline of the static mixing reactor 24, and the other end is connected to the main mixing reaction pipeline 6. A bypass valve 14 is installed on the bypass pipeline 13. Isolation valves 15 are provided at the air inlet of the pre-storage chamber side bag filter 3 and the air outlet of the pre-storage chamber side dust collector booster fan 4.

[0032] During normal desulfurization operation in this embodiment, the bypass valve 14 is closed, the isolation valve 15 remains open, and the flue gas from the pre-storage chamber flows through the main process, passing through dust removal and pressurization before entering the main mixing reaction pipeline 6. When the bag filter 3 or the dust removal pressurization fan 4 on the pre-storage chamber side malfunctions and is under maintenance, the two isolation valves 15 before and after the bag filter 3 and the dust removal pressurization fan 4 on the pre-storage chamber side are closed to isolate the faulty equipment. The bypass valve 14 is then opened, and the flue gas from the pre-storage chamber directly enters the main mixing reaction pipeline 6 through the bypass pipeline 13, transferring the entire desulfurization load to the secondary desulfurization unit 7. During operation, the amount of desulfurizing agent added can be adjusted based on the flue gas monitoring data at the chimney 10 outlet. If necessary, the dry quenching coke production load can be adjusted appropriately to ensure that the sulfur dioxide in the exhaust gas meets the standards.

[0033] Optionally, such as Figure 2 As shown, it also includes a fluidized gas supply pipeline 16 and a fluidizing blower 17; the fluidized gas supply pipeline 16 is equipped with two gas inlets, which are connected in parallel to the inlet of the fluidizing blower 17. One gas inlet is connected to the exhaust outlet of the flue gas purified by the dust removal booster blower 9 at the rear end, and the other gas inlet is connected to the exhaust outlet of the booster blower after coke oven dust removal and purification; the outlet of the fluidizing blower 17 is provided with two fluidizing branch pipes 161, which are connected to the fluidizing plate inlets of the first desulfurizing agent silo 21 and the second desulfurizing agent silo 71, respectively.

[0034] In this embodiment, two sets of process-purified flue gas are selected as the gas source. After purification, the flue gas is dry and clean, and the temperature is maintained at 50℃-70℃, without the need for additional heating. The fluidizing blower 17 pressurizes the flue gas from the two sources and then delivers it to the fluidizing plate of the silo, realizing the loose fluidization of the desulfurizing agent inside the silo, reducing the consumption of purchased compressed air and nitrogen, and reducing the system operating cost. The two gas inlets are set in parallel, and one of the gas sources can be selected.

[0035] Optionally, such as Figure 2 As shown, each fluidized branch pipe 161 of the silo is equipped with a spare external fluidized gas source branch 162 in parallel; each fluidized branch pipe 161 of the silo is also provided with a straight branch pipe 163, and the two straight branch pipes 163 are respectively connected to the first gas-material mixing device 23 and the second gas-material mixing device 73.

[0036] In this optional scheme, when the process flue gas intake pressure is insufficient or the gas source is interrupted, the system switches to the backup external fluidizing gas source branch 162 to maintain fluidization operation; the straight branch pipe 163 directly introduces the fluidizing gas flow into the gas-material mixing device, which enhances the gas flow conveying effect of the desulfurizing agent powder and reduces the probability of pipeline blockage and powder bridging.

[0037] Optionally, such as Figure 2 As shown, it also includes multiple sets of flue gas analysis instruments; The pre-storage chamber venting flue gas pipeline 1 is located upstream of the primary desulfurization unit 2 and is equipped with the first flue gas online analyzer 18 and the first flow meter 181. The main dust removal flue gas pipeline 5 is located upstream of the secondary desulfurization unit 7 and is equipped with a second flue gas online analyzer 19 and a second flow meter 191. The outlet pipe section of the dust removal booster fan 4 in the pre-storage chamber is equipped with a third online flue gas analyzer 20; The exhaust pipe section of chimney 10 is equipped with a fourth online flue gas analyzer 30. The first online flue gas analyzer 18, the first flow meter 181, the second online flue gas analyzer 19, the second flow meter 191, the third online flue gas analyzer 20, and the fourth online flue gas analyzer 30 are all connected to the interlocking control cabinet via electrical signals.

[0038] Each analytical instrument forms the data acquisition foundation of the system, providing real-time signals for subsequent automated control. The first flue gas online analyzer 18 and the first flow meter 181 collect the original parameters of the flue gas released from the pre-storage chamber; the second flue gas online analyzer 19 and the second flow meter 191 collect the original parameters of the flue gas from the main dust removal unit; the third flue gas online analyzer 20 is used to verify the quality of the flue gas after the initial desulfurization. In actual operation, the initial desulfurization efficiency can be controlled at 80%~90%, thereby reducing the processing pressure of the secondary desulfurization unit 7; the fourth flue gas online analyzer 30 is used for final emission monitoring. All instrument-collected signals are aggregated to the interlocking control cabinet.

[0039] This embodiment also provides a combined desulfurization method for dry quenching furnace vent gas and dust removal flue gas. Using the above-mentioned combined desulfurization system for dry quenching furnace vent gas and dust removal flue gas, the desulfurization method includes the following steps: S1. Collect the flue gas released from the pre-storage chamber of the dry quenching furnace. The first flue gas online analyzer 18 and the first flow meter 181 collect the sulfur dioxide concentration and flow parameters of the pre-storage flue gas in real time. Based on the collected concentration and flow parameters, match the corresponding calcium hydroxide desulfurizing agent dosage. The first rotary feeder 22 outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is transported to the static mixing reactor 24 through the first gas-material mixing device 23 and fully mixed with the flue gas released from the pre-storage chamber to complete the initial dry desulfurization. The initial desulfurization flue gas flows sequentially through the bag filter 3 on the pre-storage chamber side and the dust removal booster fan 4 on the pre-storage chamber side before being sent into the main mixing reaction pipeline 6. S2. The dust removal flue gas from the dry quenching furnace body is sent into the main mixing reaction pipeline 6 and mixed with the flue gas output from the dust removal booster fan 4 on the pre-storage chamber side to form mixed flue gas. S3. The second flue gas online analyzer 19 collects the sulfur dioxide concentration and flow parameters of the mixed flue gas. Based on the collected concentration and flow parameters, it matches the corresponding calcium hydroxide desulfurizing agent dosage. The second rotary feeder 72 outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is sent into the total mixing reaction pipeline 6 through the second gas-material mixing device 73 to fully contact and react with the mixed flue gas, thus completing the secondary desulfurization. S4. The flue gas after secondary desulfurization is sent to the rear bag filter 8 to remove dust. The flue gas after dust removal is pressurized by the rear dust removal booster fan 9 and then sent to the chimney 10 for external discharge. The fourth flue gas online analyzer 30 monitors the sulfur dioxide emission concentration of the flue gas at the outlet of the chimney 10 in real time.

[0040] The desulfurizing agent for the flue gas released from the pre-storage chamber is controlled by automatic dosing in stages. The amount of desulfurizing agent added is controlled by a staged interlocking method based on the sulfur dioxide concentration of the flue gas released from the pre-storage chamber of the dry quenching furnace before desulfurization: it is divided into several stages with intervals of 100mg / m³, and each stage corresponds to a frequency value of the first rotary feeder 22. When the concentration reaches the corresponding stage range and lasts for 1 minute, the frequency of the first rotary feeder 22 is automatically adjusted to the corresponding value of that stage.

[0041] Due to fluctuations in flue gas parameters, to avoid frequent adjustments to the feeder by the control system, a 1-minute continuous judgment time is set as an example for on-site execution. This timeframe can be divided into eight concentration levels: sulfur dioxide concentration ≤600mg / m³, >600mg / m³ and ≤700mg / m³, >700mg / m³ and ≤800mg / m³, >800mg / m³ and ≤900mg / m³, >900mg / m³ and ≤1000mg / m³, >1000mg / m³ and ≤11mg / m³. 00mg / m³, greater than 1100mg / m³ and ≤1200mg / m³, greater than 1200mg / m³; each gear is matched with a fixed operating frequency of the first rotary feeder 22; when the sulfur dioxide concentration of the flue gas released from the pre-storage chamber falls into the corresponding gear and lasts for 1 minute, the feeder frequency corresponding to that gear is executed, and the control system simultaneously retains a manual adjustment mode for intervention in special working conditions; each gear is matched with a fixed operating frequency of the first rotary feeder 22, and the control system simultaneously retains a manual adjustment mode for intervention in special working conditions.

[0042] The mixed flue gas desulfurization adopts a composite parameter-based automatic control system. The flue gas pollutant load value is obtained by multiplying the flue gas velocity by the sulfur dioxide concentration. The load value is divided into multiple composite control intervals with 100 as the dividing value. When the load value is stable in the same interval for 1 minute, the interlock control cabinet adjusts the operating frequency of the second rotary feeder 72 according to the real-time collected concentration and flow parameters. When the sulfur dioxide concentration before desulfurization of the flue gas from the main dust collector is lower than 50 mg / m³ and lasts for 8-20 minutes, the addition of desulfurizing agent is suspended. The duration of this suspension is set to be no less than one coking cycle. The coking cycle is defined as the time from the start of coking in this furnace to the start of coking in the next furnace. The start of coking is determined by the furnace cover opening signal.

[0043] The flue gas volume of the dust collector flues drastically with the coking process. The sulfur dioxide concentration alone cannot accurately reflect the desulfurization load. Therefore, the product of flue gas velocity and sulfur dioxide concentration is used as the pollution load indicator. The judgment time of 8-20 minutes is an adjustable parameter on site, which can be set in combination with the actual coking time interval of dry quenching coke. The coking operation node is referenced by the furnace cover opening signal. A manual control mode is also configured to realize manual intervention.

[0044] When desulfurization is running, the fluidizing fan 17 is started, and two independent gas sources are selected to deliver airflow to the primary desulfurization unit 2 and the secondary desulfurization unit 7. If the gas supply from the two gas sources is abnormal, the backup external fluidizing gas source branch 162 is switched to supply gas.

[0045] This step is matched with the system's fluidized air supply structure to ensure a continuous and stable airflow for powder conveying and to avoid bridging in the silo and blockage in the pipeline.

[0046] Example 1: Dry quenching coke production is normal. Flue gas is being released from the pre-storage chamber. The main dust collector is in the coke loading stage with a large air volume. The mixed flue gas pollution load is stable between 200-300 mg / m³. All system valves are in normal operating positions, with shut-off valve 12 closed and bypass valve 14 closed. Fluidizing blower 17 uses purified flue gas from the outlet of the downstream dust collector booster blower 9 or purified dust from the coke oven outlet as its fluidizing gas source. The first flue gas online analyzer 18 detects a pre-storage chamber flue gas concentration of 850 mg / m³ for 1 minute. The interlock control cabinet then switches the first rotary feeder 22 to... The primary desulfurization is completed at a frequency corresponding to 800mg / m³-900mg / m³, with the primary desulfurization efficiency maintained at 80%-90%. The flue gas from the primary desulfurization flows sequentially through the pre-storage chamber side bag filter 3 and the pre-storage chamber side dust collector booster fan 4 before being sent into the main mixing reaction pipeline 6. The mixed flue gas is adjusted according to the load range of 200-300 by the second rotary feeder 72. After staged desulfurization, the two flue gases flow sequentially through the rear bag filter 8 and the rear dust collector booster fan 9, and are finally discharged through the chimney 10. The fourth flue gas online analyzer 30 monitors the outlet emissions to ensure compliance.

[0047] Example 2: During the dry quenching coke charging interval between two furnaces, the main dust collector fan operates at low speed, and the sulfur dioxide concentration in the flue gas from the main dust collector remains stable at 35 mg / m³ for 12 minutes. This duration is not less than the single coke charging cycle. The interlock control cabinet controls the second rotary feeder 72 to suspend the addition of desulfurizing agent. The flue gas released from the pre-storage chamber continues to receive desulfurizing agent normally from the primary desulfurization unit 2. Relying on the low-sulfur flue gas after the primary desulfurization, the overall emission of the total mixed flue gas is ensured to meet the standards. Under this condition, the consumption of calcium hydroxide reagent can be reduced.

[0048] Example 3: When the second desulfurizing agent silo 71 and the second rotary feeder 72 need to be shut down for maintenance, the electric valve at the outlet of the second gas-material mixing device 73 is closed, and the shut-off valve 12 on the connecting pipeline 11 is opened. The system switches to manual control mode, relying solely on the first desulfurizing agent silo 21, the first rotary feeder 22, and the first gas-material mixing device 23 to simultaneously supply desulfurizing agent to the primary desulfurization unit 2 and the secondary desulfurization unit 7. The fluidized gas supply system maintains its original working mode, and the interlock control cabinet exits the automatic grading logic of the secondary desulfurization. The operator manually adjusts the feeder frequency based on the monitoring data of the chimney 10 outlet of the fourth flue gas online analyzer 30 to achieve maintenance without production interruption. When the equipment of the primary desulfurization unit 2 needs maintenance, the second desulfurizing agent silo 71, the second rotary feeder 72, and the second gas-material mixing device 73 in the secondary desulfurization unit 7 can simultaneously supply desulfurizing agent to the primary desulfurization unit 2 and the secondary desulfurization unit 7.

[0049] Example 4: When the pre-storage chamber side bag filter 3 or the pre-storage chamber side dust collector booster fan 4 malfunctions and needs maintenance, close the two isolation valves 15 at the inlet end of the pre-storage chamber side bag filter 3 and the outlet end of the pre-storage chamber side dust collector booster fan 4, and open the bypass valve 14; the initial desulfurization flue gas enters the main mixing reaction pipeline 6 through the bypass pipeline 13. Since the bypass bypasses the pre-storage chamber side bag filter 3, the dust carried by the flue gas directly enters the main mixing reaction pipeline 6, relying on the rear bag filter... Dust collector 8 collects dust uniformly; the interlock control cabinet, combined with the sulfur dioxide data of the initial desulfurization outlet of the third flue gas online analyzer 20, can appropriately adjust the amount of desulfurizing agent added to the second rotary feeder 72; if necessary, the dry quenching coke production load can be appropriately adjusted to ensure that the sulfur dioxide at the outlet of the chimney 10 is stably up to standard; after the bag filter 3 on the pre-storage chamber side and the dust removal booster fan 4 on the pre-storage chamber side are overhauled, close the overpass valve 14, open the isolation valve 15, and switch back to the main process flow.

[0050] Example 5: Both the outlet of the back-end dust removal booster fan 9 and the two process gas intakes of the coke oven dust removal and purification booster fan experienced insufficient pressure. The air source of the fluidizing fan 17 was abnormal. The system automatically switched to the backup external fluidizing gas source branch 162, and the external gas source supplied air to the fluidizing branch pipe 161 and the straight branch pipe 163 of the silo. The powder conveying of the silo fluidization and the gas-material mixing device was maintained. The automatic grading control logic of the first and second rotary feeders 72 remained unchanged. The entire desulfurization system operated without interruption. After the process flue gas source was restored, it switched back to the process flue gas intake mode.

[0051] The present invention has been described by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas, characterized in that: It includes a pre-storage chamber flue gas venting pipeline (1), a primary desulfurization unit (2), a pre-storage chamber side bag filter (3), a pre-storage chamber side dust removal booster fan (4), a main body dust removal flue gas pipeline (5), a total mixing reaction pipeline (6), a secondary desulfurization unit (7), a rear bag filter (8), a rear dust removal booster fan (9), and a chimney (10). The primary desulfurization unit (2) is set on the flue gas pipeline (1) of the pre-storage chamber. The primary desulfurization unit (2) includes a first desulfurizing agent silo (21), a first rotary feeder (22), a first gas-material mixing device (23), and a static mixing reactor (24). The outlet of the first desulfurizing agent silo (21) is connected to the inlet of the first rotary feeder (22). The outlet of the first rotary feeder (22) is connected to the first gas-material mixing device (23). The output end of the first gas-material mixing device (23) is connected to the static mixing reactor (24). The static mixing reactor (24) is connected in series on the flue gas pipeline (1) of the pre-storage chamber. The flue gas pipeline (1) of the pre-storage chamber passes through the primary desulfurization unit (2), the bag filter (3) on the pre-storage chamber side, and the dust removal booster fan (4) on the pre-storage chamber side before being connected to the main mixing reaction pipeline (6). The dust removal flue gas pipeline (5) is directly connected to the total mixing reaction pipeline (6); The secondary desulfurization unit (7) is arranged on the main mixing reaction pipeline (6). The secondary desulfurization unit (7) includes a second desulfurizing agent silo (71), a second rotary feeder (72), and a second gas-material mixing device (73). The outlet of the second desulfurizing agent silo (71) is connected to the inlet of the second rotary feeder (72), the outlet of the second rotary feeder (72) is connected to the second gas-material mixing device (73), and the output end of the second gas-material mixing device (73) is connected to the main mixing reaction pipeline (6). The outlet of the main mixing reaction pipeline (6) is connected to the rear bag filter (8), the rear bag filter (8) is connected to the rear dust removal booster fan (9), and the outlet of the rear dust removal booster fan (9) is connected to the chimney (10). It also includes an interlock control cabinet, which is connected to the control signals of the first rotary feeder (22) and the second rotary feeder (72).

2. The combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas according to claim 1, characterized in that: A connecting pipe (11) and a shut-off valve (12) are provided between the supply pipes of the first desulfurizing agent silo (21) and the second desulfurizing agent silo (71). The connecting pipe (11) is connected to the discharge end of the first gas-material mixing device (23) and the second gas-material mixing device (73).

3. The combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas according to claim 1, characterized in that: It also includes an overpass pipeline (13), one end of which is connected to the discharge end pipeline of the static mixing reactor (24), and the other end is connected to the main mixing reaction pipeline (6). An overpass valve (14) is installed on the overpass pipeline (13); isolation valves (15) are provided at the air inlet of the pre-storage chamber side bag filter (3) and the air outlet of the pre-storage chamber side dust collector booster fan (4).

4. The combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas according to claim 3, characterized in that: It also includes a fluidized gas supply pipeline (16) and a fluidizing blower (17); the fluidized gas supply pipeline (16) is equipped with two gas inlets, which are connected in parallel to the inlet of the fluidizing blower (17). One gas inlet is connected to the exhaust outlet of the dust removal booster blower (9) at the rear end, and the other gas inlet is connected to the exhaust end of the booster blower after coke oven dust removal and purification; the outlet of the fluidizing blower (17) is provided with two fluidized branch pipes (161) for the silo body, which are connected to the fluidized plate inlets of the first desulfurizing agent silo (21) and the second desulfurizing agent silo (71) respectively.

5. The combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas according to claim 4, characterized in that: Each fluidized branch pipe (161) of the silo is equipped with a backup external fluidized gas source branch (162) in parallel; each fluidized branch pipe (161) of the silo is also equipped with a straight branch pipe (163), and the two straight branch pipes (163) are respectively connected to the first gas-material mixing device (23) and the second gas-material mixing device (73).

6. The combined desulfurization system for dry quenching furnace venting gas and dust removal flue gas according to claim 1, characterized in that: It also includes multiple sets of flue gas analysis instruments; The pre-storage chamber venting flue gas pipeline (1) is located upstream of the primary desulfurization unit (2) and is equipped with the first flue gas online analyzer (18) and the first flow meter (181). The main dust removal flue gas pipeline (5) is located upstream of the secondary desulfurization unit (7) and is equipped with a second flue gas online analyzer (19) and a second flow meter (191). The third flue gas online analyzer (20) is installed on the outlet pipe section of the dust removal booster fan (4) in the pre-storage chamber. The exhaust pipe section of the chimney (10) is equipped with a fourth flue gas online analyzer (30); The first flue gas online analyzer (18), the first flow meter (181), the second flue gas online analyzer (19), the second flow meter (191), the third flue gas online analyzer (20), and the fourth flue gas online analyzer (30) are all connected to the interlocking control cabinet via electrical signals.

7. A method for combined desulfurization of flue gas from a dry quenching furnace and flue gas from dust removal, characterized in that, The desulfurization method using the combined desulfurization system for dry quenching furnace vent gas and dust removal flue gas as described in any one of claims 1-6 includes the following steps: S1. Collect the flue gas released from the pre-storage chamber of the dry quenching furnace. The first flue gas online analyzer (18) and the first flow meter (181) collect the sulfur dioxide concentration and flow parameters of the pre-storage flue gas in real time. Based on the collected concentration and flow parameters, match the corresponding calcium hydroxide desulfurizing agent dosage. The first rotary feeder (22) outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is transported to the static mixing reactor (24) through the first gas-material mixing device (23) and fully mixed with the flue gas released from the pre-storage chamber to complete the initial dry desulfurization. The initial desulfurization flue gas flows through the bag filter (3) on the pre-storage chamber side and the dust removal booster fan (4) on the pre-storage chamber side before being sent into the main mixing reaction pipeline (6). S2. The dust removal flue gas of the dry quenching furnace body is sent into the total mixing reaction pipeline (6) and mixed with the flue gas output by the dust removal booster fan (4) on the pre-storage chamber side to form mixed flue gas; S3. The second flue gas online analyzer (19) collects the sulfur dioxide concentration and flow parameters of the mixed flue gas. Based on the collected concentration and flow parameters, it matches the corresponding calcium hydroxide desulfurizing agent dosage. The second rotary feeder (72) outputs calcium hydroxide desulfurizing agent according to the matched dosage. The desulfurizing agent is sent into the total mixing reaction pipeline (6) through the second gas-material mixing device (73) to fully contact and react with the mixed flue gas to complete the secondary desulfurization. S4. The flue gas after secondary desulfurization is sent to the back-end bag filter (8) to remove dust. After dust removal, the flue gas is pressurized by the back-end dust removal booster fan (9) and then sent to the chimney (10) for external discharge. The fourth flue gas online analyzer (30) monitors the sulfur dioxide emission concentration of the flue gas at the outlet of the chimney (10) in real time.

8. The method for combined desulfurization of flue gas from a dry quenching furnace and flue gas from dust removal according to claim 7, characterized in that: The desulfurizing agent for the flue gas released from the pre-storage chamber is controlled by automatic addition in stages. The amount of desulfurizing agent added is controlled by a staged interlocking method based on the sulfur dioxide concentration of the flue gas released from the pre-storage chamber of the dry quenching furnace before desulfurization: it is divided into several stages with a spacing of 100mg / m³. Each stage corresponds to a frequency value of the first rotary feeder (22). When the concentration reaches the corresponding stage range and lasts for 1 minute, the frequency of the first rotary feeder (22) is automatically adjusted to the corresponding value of the stage.

9. The method for combined desulfurization of flue gas from a dry quenching furnace and flue gas from dust removal according to claim 7, characterized in that: The mixed flue gas desulfurization adopts a composite parameter graded automatic control; the flue gas pollutant load value is obtained by multiplying the flue gas flow rate and sulfur dioxide concentration, and the multi-level composite control range is divided with the load value of 100 as the dividing value. When the load value is stable in the same range for 1 minute, the interlock control cabinet adjusts the operating frequency of the second rotary feeder (72) according to the real-time collected concentration and flow parameters; when the sulfur dioxide concentration before the main dust removal flue gas desulfurization is lower than 50mg / m³ and lasts for 8-20 minutes, the addition of desulfurizing agent is suspended.

10. The method for combined desulfurization of flue gas from a dry quenching furnace and flue gas from dust removal according to claim 7, characterized in that: When desulfurization is running, start the fluidizing fan (17) and select one of the two independent gas sources to deliver the gas flow to the primary desulfurization unit (2) and the secondary desulfurization unit (7). If the gas supply from the two gas sources is abnormal, switch to the backup external fluidizing gas source branch (162) to supply gas.

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