A zinc smelting off gas treatment system

Abstract

The utility model relates to processing system technical field especially relates to a kind of zinc smelting flue gas processing system.It mainly aims at the heavy metal ions such as arsenic, mercury, selenium in zinc smelting electric dust collection outlet furnace gas can be enriched in purification system washing equipment circulating acid and the mineral dust suspended matter in furnace gas is easy to cause system blockage, increase processing difficulty, corrode equipment, affect production continuity and improve operation cost problem, propose the following technical scheme: including the first scrubber of flue gas is handled, the first scrubber outlet is provided with first circulating pump, the first circulating pump output end is connected with gas-liquid separation buffer tank by pipeline, the gas-liquid separation buffer tank exhaust pipe is connected with second scrubber;FBL filter, the FBL filter is connected with gas-liquid separation buffer tank by pipeline.The utility model can reduce circulating acid processing difficulty, reduce equipment corrosion, avoid system blockage, guarantee zinc smelting production continuity and reduce enterprise operation cost.

Description

Technical Field

[0001] This utility model relates to the field of processing system technology, and in particular to a zinc smelting flue gas treatment system. Background Technology

[0002] In zinc smelting production, flue gas treatment is a crucial step in ensuring production safety and environmental protection. Electrostatic precipitators (ESPs), as important devices for the initial purification of flue gas, primarily remove most of the dust particles. However, in actual production operation, the furnace gas discharged from the ESP outlet still carries various harmful impurities, posing challenges to subsequent purification processes. Heavy metals such as arsenic, mercury, and selenium contained in the furnace gas at the ESP outlet are transferred to the circulating acid in the scrubbing equipment after entering the subsequent purification system. As production continues, these heavy metal ions accumulate in the circulating acid, not only increasing the difficulty of acid treatment but also potentially corroding the materials of the scrubbing equipment, thus affecting its service life.

[0003] Meanwhile, the furnace gas also contains a large amount of suspended mineral dust. During the washing process of the purification system, these suspended particles enter the circulating acid system along with the flue gas. Because the suspended mineral dust particles are small and have a certain degree of stickiness, long-term accumulation can easily cause blockages in the pipes, nozzles, and filter elements of the washing equipment. System blockage not only leads to a significant decrease in washing efficiency and affects the flue gas purification effect, but also requires frequent shutdowns for cleaning and maintenance, seriously disrupting the continuity of zinc smelting production and increasing the company's production and operating costs. Therefore, this utility model proposes a zinc smelting flue gas treatment system. Utility Model Content

[0004] The purpose of this invention is to address the problems in the prior art where heavy metal ions such as arsenic, mercury, and selenium in the flue gas from zinc smelting electrostatic precipitators accumulate in the circulating acid of the purification system's washing equipment, and the suspended mineral dust in the flue gas easily causes system blockage, increasing the difficulty of treatment, corroding equipment, affecting production continuity, and increasing operating costs. This invention proposes a zinc smelting flue gas treatment system.

[0005] The technical solution of this utility model is as follows: A zinc smelting flue gas treatment system includes a first scrubber for treating the flue gas, a first circulation pump at the outlet of the first scrubber, a gas-liquid separation buffer tank connected to the output end of the first circulation pump via a pipe, and a second scrubber connected to the exhaust pipe of the gas-liquid separation buffer tank; an FBL filter connected to the gas-liquid separation buffer tank via a pipe for solid-liquid separation of the liquid discharged from the gas-liquid separation buffer tank; a sludge buffer tank located at the bottom of the FBL filter, compressed air introduced into the sludge buffer tank, a second circulation pump at the outlet of the sludge buffer tank, and a filter press connected to the output end of the second circulation pump via a pipe for pressing and filtering the sludge separated by the FBL filter.

[0006] Optionally, it also includes a configuration tank into which water and flocculant are input and stirred by air. A metering pump is installed at the outlet of the configuration tank, and the output end of the metering pump is connected to a gas-liquid separation buffer tank through a pipeline, and a rotor flow meter is installed on the pipeline.

[0007] Optionally, the top of the FBL filter is connected to the exhaust pipe of the gas-liquid separation buffer tank via a pipe.

[0008] Optionally, the clear liquid produced by the FBL filter flows by gravity through a pipe into the second scrubber to serve as makeup water.

[0009] Optionally, the top of the mud buffer tank is connected to the exhaust pipe of the gas-liquid separation buffer tank via a pipe.

[0010] Optionally, an air collection hood is provided above the filter press, and the air collection hood is connected to the exhaust pipe of the gas-liquid separation buffer tank through a pipe.

[0011] Optionally, the filtrate after filtration by the filter press flows by gravity through a pipeline to the second scrubber.

[0012] Optionally, an electric fluoropolymer-lined shut-off valve is installed in the pipeline between the first circulating pump and the gas-liquid separation buffer tank, and a level gauge is installed on the mud buffer tank.

[0013] Optionally, valves and flow meters may also be installed on each pipe.

[0014] In summary, this application includes at least one of the following beneficial technical effects:

[0015] This invention uses a first scrubber to pre-wash the flue gas, then uses a first circulating pump to transport the waste acid to a gas-liquid separation buffer tank. The flocculant added by the configuration tank and metering pump accelerates the sedimentation of impurities. The gas is then subjected to deep solid-liquid separation through an FBL filter. The slurry is subsequently dewatered by a filter press, which prevents the accumulation of mineral dust and suspended matter in the system. This solves the problem of easy clogging in traditional systems, reduces the frequency of downtime for cleaning, and ensures the continuous and stable operation of zinc smelting production.

[0016] Furthermore, by collecting the separated sulfur dioxide gas and overflowing harmful gases into the second scrubber for recycling, the clear liquid from the FBL filter and the filtrate from the filter press flow by gravity into the second scrubber for recycling, achieving efficient recycling of water resources and sulfur dioxide resources.

[0017] In summary, this invention can reduce the difficulty of circulating acid treatment, reduce equipment corrosion, avoid system blockage, ensure the continuity of zinc smelting production, and reduce enterprise operating costs. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a zinc smelting flue gas treatment system.

[0019] Figure label:

[0020] 1. First scrubber; 2. First circulating pump; 3. Gas-liquid separation buffer tank; 4. Second scrubber; 5. FBL filter; 6. Slurry buffer tank; 7. Second circulating pump; 8. Filter press; 9. Air collection hood; 10. Mixing tank; 11. Metering pump; 12. Rotor flow meter; 13. Electric fluoropolymer-lined shut-off valve; 14. Liquid level gauge. Detailed Implementation

[0021] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0022] The components of the present invention embodiments described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0023] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0024] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Example

[0027] like Figure 1 As shown, this utility model proposes a zinc smelting flue gas treatment system, including a first scrubber 1 for preliminary washing and purification of the flue gas to remove some impurities. All heavy metal ions, such as arsenic, selenium, and mercury, brought in by the furnace gas enter the circulating acid at the inlet of the first scrubber 1. The waste acid discharged from the first scrubber 1 contains a large amount of suspended mineral dust. A first circulating pump 2 is installed at the outlet of the first scrubber 1 to provide power for transporting the waste acid to subsequent equipment. The output end of the first circulating pump 2 is connected via a pipeline to a gas-liquid separation buffer tank 3 for gas-liquid separation of the waste acid to separate sulfur dioxide gas. The waste acid from the first scrubber 1 is input into the gas-liquid separation buffer tank 3 through the first circulating pump 2, achieving preliminary treatment of the waste acid. Valves are installed on both the inlet and outlet pipelines of the first circulating pump 2 for controlling pipeline opening and closing and for maintenance. An electromagnetic flowmeter is installed on the pipeline between the first circulating pump 2 and the gas-liquid separation buffer tank 3 to accurately measure the flow rate of the waste acid, facilitating real-time monitoring of the transport process. The pipeline between the first circulating pump 2 and the gas-liquid separation buffer tank 3 is equipped with an electrically powered fluoropolymer-lined shut-off valve 13, which is resistant to acid corrosion and can be remotely controlled. The valve 13 allows for adjustment of the flow path, improving the convenience and safety of system operation. The exhaust pipe of the gas-liquid separation buffer tank 3 is connected to a second scrubber 4 for the efficient absorption and recovery of the separated sulfur dioxide gas. The second scrubber 4 recovers the separated sulfur dioxide gas, achieving resource recycling.

[0028] Furthermore, the aforementioned treatment system includes an FBL filter 5 for deep solid-liquid separation of the liquid after gas-liquid separation. The FBL filter 5 is connected to the gas-liquid separation buffer tank 3 via a pipeline, and is used to perform solid-liquid separation on the liquid discharged from the gas-liquid separation buffer tank 3, removing suspended mineral dust from the liquid. The FBL filter 5 is an integral fiberglass structure, resistant to acid and corrosion, and can adapt to the highly corrosive environment of polluted acid, extending the service life of the equipment. It uses a single layer of suspended filter media, which can efficiently intercept and filter suspended solids in the liquid, improving the filtration effect. The FBL filter 5 uses automatic backwashing. During sewage discharge, the FBL filter 5 continuously receives liquid without other operations, reducing manual intervention and ensuring continuous system operation. When the FBL filter 5 discharges sewage instantaneously, the packing material achieves backwashing with the liquid level fluctuation, preventing clogging and accumulation. The bottom valve can discharge the concentrated liquid, making operation convenient and reducing maintenance costs. The top of the FBL filter 5 is connected to the exhaust pipe of the gas-liquid separation buffer tank 3 via a pipeline, used to recover sulfur dioxide gas in the gas-liquid separation buffer tank 3 and prevent gas leakage. The clarified liquid produced by FBL filter 5 flows by gravity through a pipeline to the circulation tank of the second scrubber 4 as makeup water, providing a water source for the sulfur dioxide absorption process of the second scrubber 4 and facilitating the recovery of sulfur dioxide gas. An electromagnetic flow meter and valve are installed on the pipeline discharging the clarified liquid from FBL filter 5 to monitor and control the amount of clarified liquid delivered.

[0029] Furthermore, the aforementioned treatment system includes a mud buffer tank 6 located at the bottom of the FBL filter 5 for temporary storage of the slurry produced during filtration. The slurry filtered and retained by the FBL filter 5 is intermittently discharged into the mud buffer tank 6 after automatic backwashing, preventing direct discharge and pollution. The pipeline between the FBL filter 5 and the mud buffer tank 6 is equipped with both a manual and an automatic drain valve, providing dual control to ensure a stable and reliable discharge process. Manual or automatic operation can be selected according to actual conditions. Compressed air is introduced into the mud buffer tank 6 for stirring, preventing mud settling and clumping, and ensuring uniform mud concentration. A level gauge 14 is installed on the mud buffer tank 6 to monitor the liquid level, preventing overfilling and avoiding mud overflow that could cause equipment malfunction. The outlet of the mud buffer tank 6 is equipped with a second circulation pump 7 for conveying mud to the filter press. The output end of the second circulation pump 7 is connected to a filter press 8 for dewatering the mud via a pipeline. The second circulation pump 7 conveys the mud from the mud buffer tank 6 to the filter press 8, achieving solid-liquid separation. Valves are installed on both the inlet and outlet pipes of the second circulation pump 7 for convenient equipment maintenance and pipeline control. A pressure gauge is installed on the filter press 8 to monitor the pressure in real time, ensuring that the filtration process is carried out within a safe pressure range. The second circulation pump 7 is interlocked with the level gauge 14 and the pressure gauge of the filter press 8, and controlled by a controller to achieve automated operation. The system can be stopped in time when the level or pressure is abnormal, improving system safety. The filter press 8 is used to filter the sludge separated by the FBL filter 5, reducing the sludge moisture content and facilitating subsequent sludge disposal. The top of the mud buffer tank 6 is connected to the exhaust pipe of the gas-liquid separation buffer tank 3 via a pipeline for recovering sulfur dioxide gas and reducing harmful gas emissions. A gas collection hood 9 is installed above the filter press 8 to collect the gas generated during the filtration process. The hood 9 is connected to the exhaust pipe of the gas-liquid separation buffer tank 3 via a pipeline. The filter press 8 is located in a closed machine room. A negative pressure pipeline is led from the flue gas duct of the second scrubber 4 to the top of the machine room, and another negative pressure pipeline is led to the top of the FBL filter 5 and the top of the gas-liquid separation buffer tank 3. Fluorine-lined butterfly valves are installed at each level to regulate the airflow, collecting sulfur dioxide gas and any spilled harmful gases back into the system to prevent environmental pollution and ensure a safe working environment. The filtrate from the filter press 8 flows by gravity to the second scrubber 4, enabling filtrate recycling and improving water resource utilization. The filter residue from the filter press 8 undergoes subsequent safe disposal to reduce or prevent environmental pollution.

[0030] Finally, the above-mentioned treatment system also includes a preparation tank 10 for preparing the flocculant solution. Water and flocculant are input into the preparation tank 10 and stirred by air to ensure that the flocculant and water are fully and evenly mixed, thereby improving the flocculation effect. A metering pump 11 for accurately delivering the flocculant solution is installed at the outlet of the preparation tank 10. The output of the metering pump 11 is connected to a gas-liquid separation buffer tank 3 via a pipeline. The liquid mixed in the preparation tank 10 is input into the gas-liquid separation buffer tank 3 by the metering pump 11, facilitating reaction with the waste acid and accelerating the sedimentation and separation of impurities in the waste acid, thus achieving gas-liquid separation. A rotor flow meter 12 is installed on the pipeline to monitor the input liquid volume and ensure accurate dosing of the flocculant solution.

[0031] It is worth mentioning that all the gas pipelines mentioned above are made of fiberglass, and other connecting pipelines are made of steel-lined PO pipes to prevent corrosion.

[0032] In this embodiment, firstly, the furnace gas containing heavy metal ions such as arsenic, selenium, and mercury, as well as suspended mineral dust, enters the first scrubber 1 for preliminary washing and purification. The heavy metal ions in the furnace gas dissolve into the circulating acid at the inlet of the first scrubber 1. Simultaneously, the first scrubber 1 discharges waste acid containing a large amount of suspended mineral dust after preliminary washing of the furnace gas. Subsequently, the first circulating pump 2 at the outlet of the first scrubber 1 starts, providing power for the waste acid transport, and transports the waste acid in the first scrubber 1 through pipelines to the gas-liquid separation buffer tank 3. During this process, the valves at the inlet and outlet of the first circulating pump 2 control the opening and closing of the pipeline, the electromagnetic flowmeter in the pipeline between the pump 2 and the gas-liquid separation buffer tank 3 monitors the waste acid transport flow rate in real time, and the electric fluoropolymer-lined shut-off valve 13 regulates the opening and closing of this section of the pipeline to ensure the controllability and safety of the transport process.

[0033] Meanwhile, water and flocculant are introduced into the preparation tank 10 for preparing the flocculant solution, and the mixture is stirred by introducing compressed air to ensure thorough and uniform mixing. The prepared flocculant solution is precisely delivered to the gas-liquid separation buffer tank 3 via the metering pump 11 at the outlet of the preparation tank 10. The rotor flow meter 12 on the pipeline monitors the input of the flocculant solution to ensure accurate dosing. After entering the gas-liquid separation buffer tank 3, the flocculant solution reacts with the waste acid, accelerating the sedimentation and separation of impurities in the waste acid, thus achieving gas-liquid separation.

[0034] The separated sulfur dioxide gas enters the second scrubber 4, which efficiently absorbs and recovers sulfur dioxide, through the exhaust pipe of the gas-liquid separation buffer tank 3 for resource recovery. The liquid discharged from the gas-liquid separation buffer tank 3 enters the FBL filter 5, which is used for deep solid-liquid separation, through a pipeline. The FBL filter 5 utilizes the acid and corrosion resistance of its integral fiberglass material to efficiently intercept mineral dust suspended in the liquid through a layer of suspended filter media. During operation, the FBL filter 5 uses automatic backwashing. There is no need to stop the liquid inlet during sewage discharge. During instantaneous sewage discharge, the packing material is backwashed with the fluctuation of the liquid surface to avoid clogging and accumulation. The concentrated liquid is discharged through the bottom valve. The top of the FBL filter 5 is connected to the exhaust pipe of the gas-liquid separation buffer tank 3 through a pipeline to recover any sulfur dioxide gas that may be present inside. The clear liquid produced by separation flows by gravity through a pipeline to the circulation tank of the second scrubber 4 as makeup water to provide a water source for sulfur dioxide absorption. Electromagnetic flow meters and valves on the pipeline monitor and control the amount of clear liquid delivered.

[0035] The slurry filtered and trapped by FBL filter 5 is intermittently discharged to the bottom of the slurry buffer tank 6 for temporary storage after automatic backwashing. The manual and automatic drain valves between FBL filter 5 and slurry buffer tank 6 provide dual control. Compressed air is introduced into slurry buffer tank 6 for stirring to prevent slurry settling and clumping. A level gauge 14 on the tank monitors the liquid level in real time. When the slurry reaches a certain volume, the second circulation pump 7 at the outlet of slurry buffer tank 6 starts, transporting the slurry to filter press 8 for dewatering. The inlet and outlet valves of the second circulation pump 7 are easily accessible for maintenance and control. A pressure gauge on filter press 8 monitors the filter pressure in real time, and the second circulation pump 7 is interlocked with the level gauge 14 and pressure gauge, achieving automated control via a controller. The machine will stop immediately if the liquid level or pressure is abnormal.

[0036] After the slurry is filtered in the filter press 8, the filtrate flows by gravity through a pipeline to the second scrubber 4 for recycling, while the filter residue undergoes subsequent safe disposal. The air hood 9 above the filter press 8 collects the gas generated during the filtration process and connects it to the exhaust pipe of the gas-liquid separation buffer tank 3 via a pipeline. Simultaneously, the filter press 8 is located in a closed machine room, with two negative pressure pipelines leading from the flue gas duct of the second scrubber 4 to the top of the machine room, the top of the FBL filter 5, and the top of the gas-liquid separation buffer tank 3, respectively. The airflow is regulated by fluoropolymer-lined butterfly valves to collect all sulfur dioxide and spilled harmful gases back into the system, preventing environmental pollution.

[0037] The above specific embodiments are merely optional embodiments of this utility model. Based on the technical solution of this utility model and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A zinc smelting flue gas treatment system, characterized in that, include: A first scrubber (1) for treating flue gas is provided. A first circulation pump (2) is provided at the outlet of the first scrubber (1). The output end of the first circulation pump (2) is connected to a gas-liquid separation buffer tank (3) through a pipe. The exhaust pipe of the gas-liquid separation buffer tank (3) is connected to a second scrubber (4). FBL filter (5), which is connected to gas-liquid separation buffer tank (3) through a pipe, is used to perform solid-liquid separation on the liquid discharged from gas-liquid separation buffer tank (3); A sludge buffer tank (6) is set at the bottom of the FBL filter (5). Compressed air is connected to the sludge buffer tank (6). A second circulation pump (7) is set at the outlet of the sludge buffer tank (6). The output end of the second circulation pump (7) is connected to a filter press (8) through a pipeline. The filter press (8) is used to filter the sludge separated by the FBL filter (5).

2. The zinc smelting flue gas treatment system according to claim 1, characterized in that, It also includes a configuration tank (10), in which water and flocculant are input and stirred by air. A metering pump (11) is provided at the outlet of the configuration tank (10). The output end of the metering pump (11) is connected to the gas-liquid separation buffer tank (3) through a pipeline, and a rotor flow meter (12) is provided on the pipeline.

3. The zinc smelting flue gas treatment system according to claim 2, characterized in that, The top of the FBL filter (5) is connected to the exhaust pipe of the gas-liquid separation buffer tank (3) via a pipe.

4. The zinc smelting flue gas treatment system according to claim 3, characterized in that, The clear liquid separated by the FBL filter (5) flows by gravity through a pipe into the second scrubber (4) to serve as supplementary water.

5. A zinc smelting flue gas treatment system according to claim 4, characterized in that, The top of the mud buffer tank (6) is connected to the exhaust pipe of the gas-liquid separation buffer tank (3) via a pipe.

6. The zinc smelting flue gas treatment system according to claim 5, characterized in that, An air collecting hood (9) is provided above the filter press (8), and the air collecting hood (9) is connected to the exhaust pipe of the gas-liquid separation buffer tank (3) through a pipe.

7. A zinc smelting flue gas treatment system according to claim 6, characterized in that, The filtrate after filtration by the filter press (8) flows by gravity through a pipe to the second scrubber (4).

8. The zinc smelting flue gas treatment system according to claim 7, characterized in that, An electric fluoropolymer-lined shut-off valve (13) is installed in the pipeline between the first circulating pump (2) and the gas-liquid separation buffer tank (3), and a level gauge (14) is installed on the mud buffer tank (6).

9. A zinc smelting flue gas treatment system according to claim 8, characterized in that, It also includes valves and flow meters installed on each pipeline.

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