A foundry plant off-gas purification device

Abstract

The utility model provides a kind of foundry workshop waste gas purification device, belong to waste gas purification technical field, the foundry workshop waste gas purification device includes waste gas collecting cover, pretreatment filter, cyclone separator, activated carbon adsorption tower, wet scrubber, induced draft fan, discharge chimney and control valve, the waste gas collecting cover is set in the waste gas generation area above foundry workshop, the pretreatment filter with the waste gas collecting cover is connected by first connecting pipeline, the cyclone separator with the pretreatment filter is connected by second connecting pipeline, the activated carbon adsorption tower with the cyclone separator is connected by third connecting pipeline, the wet scrubber with the activated carbon adsorption tower is connected by fourth connecting pipeline, the induced draft fan with the wet scrubber is connected by fifth connecting pipeline;The utility model can solve the problem that foundry workshop waste gas purification device structure is complex, purification efficiency is low, operating cost is high.

Description

Technical Field

[0001] This utility model belongs to the field of waste gas purification technology, specifically, it relates to a waste gas purification device for a foundry workshop. Background Technology

[0002] Traditional waste gas treatment in foundries primarily employs single filtration or adsorption methods, resulting in limited effectiveness. During the casting process, smelting, pouring, and cooling generate large quantities of waste gas containing metal particles, harmful gases, and dust. This waste gas is complex in composition, high in temperature, and corrosive. Existing waste gas treatment equipment typically only treats one type of pollutant, failing to achieve comprehensive treatment of multiple pollutants. For example, traditional baghouse dust collectors can only remove particulate matter and are ineffective against gaseous pollutants; activated carbon adsorption devices can only treat organic gases and have limited capacity for particulate matter removal. Furthermore, the structural design of existing equipment is unreasonable, with a lack of effective coordination between various treatment units, leading to low overall treatment efficiency.

[0003] Furthermore, the existing equipment suffers from high operating and maintenance costs, frequent filter media replacements, and a high failure rate, severely impacting the normal production of foundry enterprises. These problems not only affect the effectiveness of waste gas treatment but also increase the operating costs of enterprises, hindering the sustainable production of the foundry industry.

[0004] Therefore, considering the above, existing technologies suffer from problems such as complex structure, low purification efficiency, and high operating costs in casting workshop exhaust gas purification devices. Utility Model Content

[0005] In view of this, the present invention provides a casting workshop exhaust gas purification device that can solve the problems of complex structure, low purification efficiency and high operating cost of casting workshop exhaust gas purification devices.

[0006] This utility model is implemented as follows:

[0007] This utility model provides a waste gas purification device for a foundry workshop, including a waste gas collection hood, a pretreatment filter, a cyclone separator, an activated carbon adsorption tower, a wet scrubbing tower, an induced draft fan, an exhaust chimney, and control valves. The waste gas collection hood is installed above the waste gas generation area of ​​the foundry workshop. The pretreatment filter is connected to the waste gas collection hood via a first connecting pipe. The cyclone separator is connected to the pretreatment filter via a second connecting pipe. The activated carbon adsorption tower is connected to the cyclone separator via a third connecting pipe. The wet scrubbing tower is connected to the activated carbon adsorption tower via a fourth connecting pipe. The induced draft fan is connected to the wet scrubbing tower via a fifth connecting pipe. The exhaust chimney is connected to the induced draft fan via a sixth connecting pipe. The control valves are respectively installed on the first, second, third, fourth, fifth, and sixth connecting pipes.

[0008] The technical effects of the waste gas purification device for a foundry workshop provided by this utility model are as follows: By setting up a waste gas collection hood, the waste gas generated in the foundry workshop is effectively collected, preventing the waste gas from spreading within the workshop; by setting up a pre-treatment filter, the collected waste gas is initially filtered to remove large particulate impurities; by setting up a cyclone separator, particulate matter in the waste gas is separated, improving purification efficiency; by setting up an activated carbon adsorption tower, harmful gases in the waste gas are adsorbed and purified; by setting up a wet scrubbing tower, the waste gas is further scrubbed and purified; by setting up an induced draft fan, the entire purification system is powered; by setting up an exhaust chimney, the purified waste gas is safely discharged; and by setting up control valves, each purification stage is precisely controlled.

[0009] Based on the above technical solution, the waste gas purification device for a foundry workshop of this utility model can be further improved as follows:

[0010] The exhaust gas collection hood is equipped with a guide plate, which has an arc-shaped structure, and the multiple guide plates are evenly distributed inside the exhaust gas collection hood.

[0011] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by setting up the guide plate, the airflow distribution inside the exhaust gas collection hood is improved, so that the exhaust gas can enter the collection system more evenly, avoiding the reduction in collection efficiency caused by local airflow turbulence. At the same time, the arc-shaped guide plate can reduce airflow resistance and improve the overall efficiency of exhaust gas collection.

[0012] Furthermore, the pretreatment filter is provided with a metal wire mesh layer, which is divided into a coarse mesh layer and a fine mesh layer. The coarse mesh layer is located at the air inlet end of the pretreatment filter, and the fine mesh layer is located at the air outlet end of the pretreatment filter.

[0013] The beneficial effects of adopting the above-mentioned improved scheme are as follows: by setting a metal wire mesh layer, the exhaust gas entering the pretreatment filter is filtered in layers. The coarse mesh layer first captures large particulate impurities, and the fine mesh layer further filters small particulate matter. This layered filtration method improves filtration efficiency and extends the service life of the filter. At the same time, the metal wire mesh layer has good high temperature resistance and is suitable for the high temperature environment of the foundry workshop.

[0014] Furthermore, the inner wall of the cyclone separator is provided with helical guide blades, the helical angle of which is 15 degrees to 45 degrees, and the helical guide blades are continuously arranged along the axial direction of the cyclone separator.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by setting spiral guide vanes, the exhaust gas entering the cyclone separator forms a stable spiral flow, which enhances the centrifugal separation effect and improves the separation efficiency of particulate matter. The reasonable setting of the spiral angle ensures the stability of the airflow and the optimization of the separation effect. The continuously set guide vanes ensure the continuity and stability of the entire separation process.

[0016] Furthermore, the activated carbon adsorption tower is provided with multiple layers of activated carbon adsorption beds, and a supporting grid is provided between the multiple layers of activated carbon adsorption beds. The supporting grid is made of stainless steel.

[0017] The beneficial effects of adopting the above-mentioned improved scheme are as follows: by setting up a multi-layer activated carbon adsorption bed, the contact area and contact time between the waste gas and the activated carbon are increased, thereby improving the adsorption efficiency of harmful gases. The setting of the support grid ensures the stability of the activated carbon bed and prevents the loss of activated carbon particles. The stainless steel material has good corrosion resistance and is suitable for the harsh environment of the foundry workshop, thus extending the service life of the equipment.

[0018] Furthermore, the wet scrubbing tower is provided with a packing layer, which includes an upper packing layer and a lower packing layer, and a liquid distributor is provided between the upper packing layer and the lower packing layer.

[0019] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by setting up a packing layer, the contact area between the waste gas and the washing liquid is increased, thus improving the washing efficiency. The layered packing layer can achieve multi-stage washing, further improving the purification effect. The setting of the liquid distributor ensures the uniform distribution of the washing liquid, avoids the problem of insufficient local washing, and improves the overall treatment efficiency of the washing tower.

[0020] Furthermore, the ratio of the impeller diameter to the casing diameter of the induced draft fan is 0.6 to 0.8, and the number of blades of the induced draft fan is 8 to 12.

[0021] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by rationally designing the ratio of the impeller diameter to the casing diameter of the induced draft fan, the efficient operation of the induced draft fan is ensured. The optimized setting of the number of blades not only ensures sufficient air volume, but also avoids the increase in energy consumption caused by too many blades. This optimization of design parameters enables the induced draft fan to have good performance and energy efficiency ratio when treating waste gas in the foundry workshop.

[0022] Furthermore, the control valve is a pneumatic regulating valve, the valve body of which is made of cast iron and the valve core of which is made of stainless steel.

[0023] The beneficial effects of adopting the above-mentioned improved scheme are as follows: by using a pneumatic regulating valve, precise control of the waste gas flow rate is achieved, with fast response speed and high control accuracy. The valve body made of cast iron has good wear resistance and economy, and the valve core made of stainless steel has excellent corrosion resistance, making it suitable for the corrosive environment of waste gas in foundry workshops and extending the service life of the control valve.

[0024] Furthermore, the height of the exhaust chimney is 15 to 30 meters, the inner diameter of the exhaust chimney is 0.8 to 1.5 meters, and the top of the exhaust chimney is equipped with a rain cap.

[0025] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by rationally designing the height and inner diameter of the exhaust chimney, the effective diffusion of the purified exhaust gas is ensured, and the accumulation of exhaust gas near the ground is avoided. The optimized setting of the height and inner diameter not only meets the environmental protection requirements, but also ensures the economy of the system. The setting of the rain cap prevents rainwater from entering the interior of the chimney, thus protecting the normal operation of the purification system.

[0026] Furthermore, the inner surface of the exhaust gas collection hood is provided with a heat insulation layer, which is made of refractory fiber material and has a thickness of 50 mm to 100 mm.

[0027] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by setting up a heat insulation layer, the heat damage of high-temperature exhaust gas in the foundry workshop to the collection hood is effectively blocked, and the structural integrity of the collection hood is protected. The refractory fiber material has excellent heat insulation and high temperature resistance properties, and is suitable for the high-temperature environment of the foundry workshop. The reasonable thickness of the heat insulation layer not only ensures the heat insulation effect, but also controls the equipment cost.

[0028] Compared with existing technologies, the beneficial effects of the foundry workshop exhaust gas purification device provided by this utility model are as follows: Through a multi-stage purification system, it effectively solves the technical problems of low purification efficiency and high operating costs in existing technologies. First, the design of the exhaust gas collection hood combined with the guide plate achieves efficient collection of exhaust gas from the foundry workshop, preventing the diffusion of exhaust gas within the workshop and improving treatment efficiency from the source. Second, the layered filtration of the metal wire mesh in the pretreatment filter effectively removes large particulate impurities from the exhaust gas, protecting subsequent treatment equipment and extending its service life. Third, the spiral guide vane design of the cyclone separator significantly improves the separation efficiency of particulate matter and reduces the load on subsequent treatment equipment. The multi-layer adsorption bed design of the activated carbon adsorption tower significantly improves the adsorption efficiency of harmful gases, while the supporting grid ensures the stability of the activated carbon bed. The packing layer and liquid distributor design of the wet scrubbing tower achieves deep scrubbing and purification of the exhaust gas, further improving the treatment effect. The optimized design of the induced draft fan ensures stable system operation, and the precise control of the pneumatic regulating valve enables refined management of the treatment process. Through the synergistic effect of multi-stage treatment, the entire system achieves efficient purification of waste gas from the foundry workshop, with a treatment efficiency that is more than 30% higher than that of existing technologies and an operating cost that is more than 25% lower, providing foundry enterprises with an economical and efficient waste gas treatment solution. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a waste gas purification device for a foundry workshop.

[0031] Figure 2 This is a schematic diagram of the internal metal mesh layer of the pretreatment filter;

[0032] Figure 3 A schematic diagram showing the location of the spiral guide vanes inside a cyclone separator;

[0033] Figure 4 This is a schematic diagram of the activated carbon adsorption bed inside the activated carbon adsorption tower.

[0034] The attached diagram lists the components represented by each number as follows:

[0035] 10. Exhaust gas collection hood; 101. Baffle plate; 11. Pretreatment filter; 111. Coarse mesh layer; 112. Fine mesh layer; 12. Cyclone separator; 121. Spiral guide vane; 13. Activated carbon adsorption tower; 131. Activated carbon adsorption bed; 132. Support grid; 14. Wet scrubbing tower; 15. Exhaust fan; 16. Exhaust chimney; 17. Control valve; 18. First connecting pipe; 19. Second connecting pipe; 20. Third connecting pipe; 21. Fourth connecting pipe; 22. Fifth connecting pipe; 23. Sixth connecting pipe. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0037] Example 1:

[0038] like Figure 1-4 The image shows a first embodiment of a foundry workshop exhaust gas purification device provided by this utility model. In this embodiment, it includes an exhaust gas collection hood 10, a pretreatment filter 11, a cyclone separator 12, an activated carbon adsorption tower 13, a wet scrubbing tower 14, an induced draft fan 15, an exhaust chimney 16, and control valves 17. The exhaust gas collection hood is installed above the exhaust gas generation area of ​​the foundry workshop. The pretreatment filter is connected to the exhaust gas collection hood via a first connecting pipe 18. The cyclone separator is connected to the pretreatment filter via a second connecting pipe 19. The activated carbon adsorption tower is connected to the cyclone separator via a third connecting pipe 20. The wet scrubbing tower is connected to the activated carbon adsorption tower via a fourth connecting pipe 21. The induced draft fan is connected to the wet scrubbing tower via a fifth connecting pipe 22. The exhaust chimney is connected to the induced draft fan via a sixth connecting pipe 23. Control valves are respectively installed on the first, second, third, fourth, fifth, and sixth connecting pipes.

[0039] In the above technical solution, each connecting pipe is fixedly installed with the adjacent mechanism by flange connection mechanism and bolts on both sides.

[0040] In the above technical solution, a guide plate 101 is provided inside the exhaust gas collection hood. The guide plate has an arc-shaped structure, and multiple guide plates are evenly distributed inside the exhaust gas collection hood.

[0041] Furthermore, in the above technical solution, a metal wire mesh layer is provided inside the pretreatment filter. The metal wire mesh layer is divided into a coarse mesh layer 111 and a fine mesh layer 112. The coarse mesh layer is provided at the air inlet end of the pretreatment filter, and the fine mesh layer is provided at the air outlet end of the pretreatment filter.

[0042] Furthermore, in the above technical solution, the inner wall of the cyclone separator is provided with a spiral guide blade 121, the spiral angle of which is 15 degrees to 45 degrees, and the spiral guide blade is continuously arranged along the axial direction of the cyclone separator.

[0043] Furthermore, in the above technical solution, the activated carbon adsorption tower is provided with a multi-layer activated carbon adsorption bed 131, and a support grid 132 is provided between the multi-layer activated carbon adsorption beds. The support grid is made of stainless steel.

[0044] Furthermore, in the above technical solution, a packing layer is provided inside the wet scrubbing tower, the packing layer includes an upper packing layer and a lower packing layer, and a liquid distributor is provided between the upper packing layer and the lower packing layer.

[0045] Furthermore, in the above technical solution, the ratio of the impeller diameter to the casing diameter of the induced draft fan is 0.6 to 0.8, and the number of blades of the induced draft fan is 8 to 12.

[0046] Furthermore, in the above technical solution, the control valve is a pneumatic regulating valve, the valve body of which is made of cast iron, and the valve core of which is made of stainless steel.

[0047] Furthermore, in the above technical solution, the height of the exhaust chimney is 15 to 30 meters, the inner diameter of the exhaust chimney is 0.8 to 1.5 meters, and a rain cap is installed on the top of the exhaust chimney.

[0048] Furthermore, in the above technical solution, the inner surface of the exhaust gas collection hood is provided with a heat insulation layer, which is made of refractory fiber material and has a thickness of 50 mm to 100 mm.

[0049] The specific operating steps of this utility model are as follows: First, start the induced draft fan to establish negative pressure in the system. Then, sequentially open the control valves at each level to adjust the exhaust gas flow rate to the design value. During system operation, the exhaust gas is first collected by the exhaust gas collection hood and evenly enters the pretreatment filter under the action of the guide plate. Large particulate impurities are removed through layered filtration of the metal wire mesh layer. The pretreated exhaust gas enters the cyclone separator, where a rotating airflow is formed under the action of the spiral guide vanes, achieving centrifugal separation of particulate matter. The separated exhaust gas enters the activated carbon adsorption tower, where harmful gases are removed through the adsorption of the multi-layer activated carbon adsorption bed. Next, the exhaust gas enters the wet scrubbing tower, where further purification is achieved through full contact between the packing layer and the scrubbing liquid. Finally, the purified exhaust gas is safely discharged into the atmosphere through the exhaust chimney by the induced draft fan. In daily operation, it is necessary to regularly check the operating status of each treatment unit, replace the metal wire mesh layer of the pretreatment filter in a timely manner, regenerate or replace the activated carbon adsorption bed periodically, replenish the scrubbing liquid in the wet scrubbing tower, and clean the collection chamber of the cyclone separator to ensure the normal operation of the system. By precisely adjusting the valves, the processing capacity of each treatment unit can be dynamically adjusted according to changes in the amount of waste gas generated, thereby optimizing the system's operation and ensuring the stability and economy of the waste gas treatment effect.

[0050] The following is a specific embodiment of this utility model: A large foundry enterprise has a production workshop area of ​​2000 square meters, mainly producing cast iron and cast steel parts, with a daily output of approximately 50 tons. The workshop is equipped with four medium-frequency induction melting furnaces, two electric arc furnaces, and corresponding casting equipment. During the production process, the exhaust gas generated in the melting process reaches a temperature of 800-1000℃, containing a large amount of metal oxide particles and harmful gases; the exhaust gas generated in the casting process has a temperature between 500-700℃, containing metal vapor and organic gases; the exhaust gas generated in the cooling process has a relatively lower temperature but contains a large amount of dust and odorous gases. To address this complex composition of exhaust gases, the enterprise adopted the foundry workshop exhaust gas purification device of this utility model.

[0051] In practice, eight exhaust gas collection hoods were installed above each smelting furnace and casting equipment. Each hood measures 3 meters × 2 meters × 1.5 meters and contains six arc-shaped guide plates made of high-temperature resistant stainless steel. The inner surface of the hood is lined with an 80-millimeter-thick refractory fiber insulation layer, effectively preventing heat damage from the high-temperature exhaust gas. The pretreatment filter is a cylindrical structure with a diameter of 1.5 meters and a height of 2.5 meters, containing three layers of metal wire mesh: a coarse layer of 5-millimeter-aperture stainless steel wire mesh and a fine layer of 2-millimeter-aperture stainless steel wire mesh. The cyclone separator has a diameter of 2 meters and a height of 6 meters, with spiral guide blades at a 30-degree angle on its inner wall, made of wear-resistant alloy steel. The activated carbon adsorption tower has a diameter of 3 meters and a height of 8 meters, containing four layers of activated carbon adsorption beds, each 1 meter thick, with activated carbon particles of 8-16 mesh, and a total loading capacity of 15 tons. The wet scrubbing tower has a diameter of 2.5 meters and a height of 12 meters. It has two layers of packing material, using Raschig rings made of polypropylene, with a rotary liquid distributor between the packing layers. The induced draft fan is a centrifugal fan with an impeller diameter of 1.2 meters, 10 blades, and an air volume of 50,000 cubic meters per hour. The control valves are pneumatic regulating valves with cast iron bodies and stainless steel cores, and a response time of less than 5 seconds. The exhaust chimney is 25 meters high with an inner diameter of 1.2 meters and is topped with a rain cap. After the system was put into operation, a third-party testing agency found that the particulate matter removal rate reached 99.5% and the harmful gas removal rate reached over 95%, fully meeting the requirements of national environmental protection standards. The system operates stably, is easy to maintain, and its annual operating cost is 28% lower than the original equipment, creating significant economic and environmental benefits for the company.

[0052] Example 2:

[0053] A medium-sized foundry specializes in producing non-ferrous metal castings, primarily aluminum alloy and copper alloy castings. The workshop covers 1200 square meters and is equipped with three gas-fired melting furnaces and corresponding die-casting equipment. Because the melting temperature of non-ferrous metals is relatively low, the resulting waste gas contains a significant amount of organic gases and metal vapors, causing substantial environmental pollution. Based on its specific production characteristics, the company adopted an improved waste gas purification device for its foundry workshop, as described in this utility model.

[0054] In practice, six exhaust gas collection hoods were installed above three smelting furnaces and six die-casting machines, each measuring 2.5 meters × 1.8 meters × 1.2 meters and containing four arc-shaped guide plates. Considering the relatively low smelting temperature of non-ferrous metals, the insulation layer of the collection hoods was set to 60 millimeters thick. The pretreatment filter adopted a cylindrical structure with a diameter of 1.2 meters and a height of 2 meters, containing two layers of metal wire mesh to effectively remove metal particles from the exhaust gas. The cyclone separator had a diameter of 1.5 meters and a height of 4.5 meters, with a spiral guide vane angle of 25 degrees, adapted to the characteristics of non-ferrous metal exhaust gas. The activated carbon adsorption tower had a diameter of 2.5 meters and a height of 6 meters, containing three layers of activated carbon adsorption beds, each 1.2 meters thick, with a total activated carbon loading of 10 tons. Coconut shell activated carbon with a high iodine value was selected to address the high organic gas content in the non-ferrous metal exhaust gas. The wet scrubbing tower has a diameter of 2 meters and a height of 10 meters. It features two layers of packing material and uses an alkaline solution for scrubbing, effectively neutralizing acidic gases in the exhaust. The induced draft fan is a corrosion-resistant centrifugal fan with an impeller diameter of 1 meter, 8 blades, and an air volume of 35,000 cubic meters per hour. All control valves are pneumatically operated and equipped with an automatic control system that automatically adjusts the operating parameters of each treatment unit based on changes in exhaust gas generation. The exhaust chimney is 20 meters high and has an inner diameter of 1 meter, meeting the requirements of the local environmental protection department. After three months of continuous operation and monitoring, all indicators have consistently met standards, with a particulate matter removal rate of 99.2% and a harmful gas removal rate exceeding 93%. The system's energy consumption has been reduced by 35% compared to the original equipment, and maintenance costs have been reduced by 40%, providing strong environmental protection for the company in the face of fierce market competition.

[0055] Specifically, the principle of this invention is as follows: Based on the synergistic mechanism of multi-stage purification treatment, comprehensive purification of foundry workshop exhaust gas is achieved through the organic combination of physical separation, chemical adsorption, and wet scrubbing. The exhaust gas collection hood utilizes negative pressure to effectively collect the generated exhaust gas, and the arc-shaped design of the guide plate, based on fluid mechanics principles, improves airflow distribution and increases collection efficiency. The pretreatment filter employs a layered filtration principle, with the combined use of coarse and fine mesh layers to effectively capture particles of different sizes. The cyclone separator, based on centrifugal separation principles, uses the rotating airflow generated by spiral guide blades to achieve separation based on the density difference between particles and gas. The activated carbon adsorption tower, based on physical adsorption principles, features a multi-layer adsorption bed design that increases contact area and residence time, improving adsorption efficiency. The wet scrubbing tower, based on gas-liquid mass transfer principles, increases the gas-liquid contact area through a packing layer, achieving the dissolution and chemical reaction of harmful gases. The induced draft fan provides system power, ensuring smooth flow of exhaust gas between each treatment unit. Control valves precisely adjust the airflow of each treatment unit to achieve optimized system operation. The design of the entire system follows the basic principles of waste gas treatment. Through the synergistic effect of multiple purification mechanisms, it achieves efficient treatment of waste gas with complex components. The technical solution is scientific and reasonable and meets the actual engineering needs of waste gas treatment.

Claims

1. A waste gas purification device for a foundry workshop, comprising a waste gas collection hood, a pretreatment filter, a cyclone separator, an activated carbon adsorption tower, a wet scrubbing tower, an induced draft fan, an exhaust chimney, and control valves, wherein the waste gas collection hood is disposed above the waste gas generation area of ​​the foundry workshop; the pretreatment filter is connected to the waste gas collection hood via a first connecting pipe; the cyclone separator is connected to the pretreatment filter via a second connecting pipe; the activated carbon adsorption tower is connected to the cyclone separator via a third connecting pipe; the wet scrubbing tower is connected to the activated carbon adsorption tower via a fourth connecting pipe; the induced draft fan is connected to the wet scrubbing tower via a fifth connecting pipe; and the exhaust chimney is connected to the induced draft fan via a sixth connecting pipe; the control valves are respectively disposed on the first, second, third, fourth, fifth, and sixth connecting pipes, characterized in that... The exhaust gas collection hood is equipped with guide plates, which have an arc-shaped structure, and multiple guide plates are evenly distributed within the exhaust gas collection hood. The pretreatment filter is equipped with a metal wire mesh layer, which is divided into a coarse mesh layer and a fine mesh layer. The inner wall of the cyclone separator is equipped with spiral guide vanes, the spiral angle of which is 15 degrees to 45 degrees. The activated carbon adsorption tower is equipped with multiple layers of activated carbon adsorption beds, and supporting grids are arranged between the multiple layers of activated carbon adsorption beds. The wet scrubbing tower is equipped with a packing layer, which includes an upper packing layer and a lower packing layer, and a liquid distributor is arranged between the upper packing layer and the lower packing layer.

2. The waste gas purification device for a foundry workshop according to claim 1, characterized in that, The coarse mesh layer is disposed at the air inlet end of the pretreatment filter, and the fine mesh layer is disposed at the air outlet end of the pretreatment filter.

3. The waste gas purification device for a foundry workshop according to claim 2, characterized in that, The spiral guide vanes are continuously arranged along the axial direction of the cyclone separator.

4. The waste gas purification device for a foundry workshop according to claim 3, characterized in that, The supporting grid is made of stainless steel.

5. The waste gas purification device for a foundry workshop according to claim 4, characterized in that, The ratio of the impeller diameter to the casing diameter of the induced draft fan is 0.6 to 0.8, and the number of blades of the induced draft fan is 8 to 12.

6. The waste gas purification device for a foundry workshop according to claim 5, characterized in that, The control valve is a pneumatic regulating valve. The valve body of the pneumatic regulating valve is made of cast iron, and the valve core of the pneumatic regulating valve is made of stainless steel.

7. The waste gas purification device for a foundry workshop according to claim 6, characterized in that, The height of the exhaust chimney is 15 to 30 meters, the inner diameter of the exhaust chimney is 0.8 to 1.5 meters, and the top of the exhaust chimney is equipped with a rain cap.

8. The waste gas purification device for a foundry workshop according to claim 7, characterized in that, The inner surface of the exhaust gas collection hood is provided with a heat insulation layer, which is made of refractory fiber material and has a thickness of 50 mm to 100 mm.

Images