A device for removing dust from water-containing flue gas in a heavy metal smelting process

Abstract

The utility model relates to the field of nonferrous heavy metal smelting technology discloses a kind of water-containing flue gas dust removal devices in heavy metal smelting process, including flue gas spraying tower, spraying water pump, flue gas washing tower, backflushing pump, air duct, fan, underflow pump.The utility model can remove water vapor and some toxic and harmful gaseous pollutants in gas while removing dust particles in dust-containing gas, dust collection effect is good, purification efficiency reaches 98%, can handle 0.1μm or more dust, washing precipitate can return system recycling, no secondary pollutant generation, average particulate matter of flue gas discharge is reduced to 5mg / Nm 3 The following fully meets the requirements of new environmental protection regulations, and reduces the emission of cadmium-containing flue gas particulate matter, and improves the ability to resist safety and environmental protection risks.

Description

Technical Field

[0001] This utility model relates to the field of non-ferrous heavy metal smelting technology, and in particular to a dust removal device for water-containing flue gas during heavy metal smelting. Background Technology

[0002] The copper-cadmium slag produced by hydrometallurgical zinc refining undergoes a combined process of hydrometallurgical extraction and pyrometallurgical smelting. The resulting sponge cadmium briquettes are then smelted in a pyrometallurgical sponge cadmium furnace to produce crude cadmium. During the pyrometallurgical smelting process, cadmium-containing flue gas is generated. This flue gas has a high moisture content (approximately 20%) and a particulate matter content of 100 mg / m³. 3 The flue gas temperature is around 30℃. This flue gas must be purified and dust-removed by a purification and dust removal device before being discharged in compliance with standards. Therefore, a baghouse dust collector with a filtration area of ​​89㎡ and a filtration efficiency of 85% is installed in the pyrometallurgical sponge cadmium furnace. However, because the baghouse dust collector operates at room temperature, which is lower than the flue gas mist point (40-50℃), the on-site conditions do not meet the usage requirements of the baghouse dust collector. The baghouse dust collector has poor dust removal efficiency for flue gas with high moisture content. Through frequent cleaning and replacement of the filter bags, the particulate matter index of the discharged flue gas barely meets the standard (40-60 mg / m³). 3 This cannot meet the requirement of 10 mg / m³ for particulate matter emissions from flue gas. 3 New environmental protection standards. Utility Model Content

[0003] The purpose of this invention is to provide a dust removal device for water-containing flue gas during heavy metal smelting, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A dust removal device for water-containing flue gas during heavy metal smelting includes a flue gas spray tower, a spray water pump, a flue gas scrubbing tower, a backwash pump, an induced draft duct, a fan, and a submersible pump. The flue gas spray tower is located outside the smelting furnace building and has two layers of spray packing inside. The spray water pump provides circulating spray slurry to the spray layers. The induced draft duct is connected to the flue gas hood on the smelting furnace, guiding the dust-containing flue gas to the bottom of the flue gas spray tower. After spraying and washing, the particulate matter in the flue gas is reduced, and the remaining flue gas enters the flue gas scrubbing tower. The gas scrubbing tower is connected to the flue gas spray tower via a flue gas pipeline. It contains two layers of fresh water spray and one layer of wire mesh demister. A backwash pump performs secondary backwashing on the exhaust gas. The fan is connected to the flue gas scrubbing tower via a pipeline, discharging the purified flue gas through a chimney. The bottom of the flue gas spray tower has a conical structure and is equipped with pipeline valves for periodically cleaning the deposited slurry containing particulate matter. The slurry is transported via pipeline to a residual liquid pit within the plant. A submersible pump is installed in the pit for recovering valuable metal dust particles.

[0006] The spray water circulation cycle of the spray water pump in the flue gas spray tower is 48 hours.

[0007] The water storage sections of the spray tower and washing tower, as well as the outdoor water supply pipelines, are all wrapped with electric heating belts, and the outer shell of the tower is insulated with aluminum sheet.

[0008] The spray tower and washing tower are made of fiberglass, with an integrated tower and trough design. The bottom of the tower is the slurry storage section, and the top is the washing section.

[0009] The slurry discharged from the spray tower is transported through pipelines to the secondary replacement residual liquid pit, and then returned to the primary replacement slurry tank by a submersible pump.

[0010] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0011] This invention removes dust particles from dust-laden gas, as well as water vapor and certain toxic and harmful gaseous pollutants. It exhibits excellent dust collection efficiency, reaching 98%, and can handle dust particles larger than 0.1 μm. The washed sediment can be returned to the system for recycling, resulting in no secondary pollutant generation. The average particulate matter content in the exhaust gas is reduced to 5 mg / Nm³. 3 The following fully meet the requirements of the new environmental regulations and reduce the emission of cadmium-containing particulate matter in flue gas, thereby enhancing the ability to resist safety and environmental risks. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structural connection of this utility model.

[0013] Attached figures and their names: 1. Smelting furnace; 2. Flue gas hood; 3. Exhaust duct; 4. Flue gas spray tower; 5. Flue gas scrubbing tower; 6. Spray water pump; 7. Backwash pump; 8. Sump; 9. Submersible pump; 10. Fan. Detailed Implementation

[0014] 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. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0015] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0016] like Figure 1 As shown, this utility model provides a dust removal device for water-containing flue gas during heavy metal smelting, including a flue gas spray tower 4, a spray water pump 6, a flue gas scrubbing tower 5, a backwash pump 7, an exhaust duct 3, a fan 10, and a submersible pump 9. The flue gas spray tower 4 is located outside the smelting furnace 1 workshop and contains two layers of spray packing. The spray water pump 7 is installed inside the flue gas spray tower 4 to provide spray slurry for the spray layers, and the spray water is recycled within the tower. The exhaust duct 3 is connected to the exhaust duct installed inside the smelting furnace 1. The flue gas is connected to the flue gas hood, which guides the dust-laden flue gas generated by the heavy metal smelting furnace to the bottom of the flue gas scrubbing tower 4. The particulate matter in the flue gas is reduced by the spraying and washing in the flue gas scrubbing tower 4. The bottom cone of the flue gas scrubbing tower 4 is equipped with corresponding pipeline valves to regularly clean the sediment in the tower. The slurry containing particulate matter deposited at the bottom of the tower is sent to the residual liquid pit 8 in the plant through pipeline. The submersible pump 9 is installed in the pit 8 to recover the dust particles containing valuable metal dust. The flue gas after dust reduction enters the flue gas scrubbing tower 5. The flue gas scrubbing tower 5 is located next to the flue gas scrubbing tower 4 and is connected to it through a flue gas pipeline. The scrubbing tower is equipped with two layers of fresh water spray and one layer of wire mesh demister. The backwash pump 7 is installed in the scrubbing tower to perform secondary backwashing on the tail gas and residual gas of the spray tower. The fan 10 is connected to the scrubbing tower through a pipeline and discharges the scrubbed flue gas through a 20-meter-high chimney.

[0017] Two layers of packing spray layer are installed inside the flue gas scrubbing tower 4. A 7.5kW spray water pump 6 is installed inside the flue gas scrubbing tower 4 to provide spray slurry to the spray layer. After the water-containing flue gas enters the bottom of the scrubbing tower, it flows upward in an vortex and comes into counter-current contact with the multi-layer spray mist flowing downward. The water-containing flue gas is fully purified through vortex sedimentation, multi-layer spraying, and packing adsorption. The two spray layers of the scrubbing tower scrub the flue gas. The spray water is recycled in the tower body with a circulation cycle of 48 hours. After the smelting furnace flue gas passes through the scrubbing tower, the particulate matter in the flue gas is reduced. The remaining tail gas enters the scrubbing tower. Pipeline valves are installed at the bottom cone of the scrubbing tower body to clean the sediment in the tower body regularly. The slurry containing particulate matter deposited at the bottom of the tower is sent to the residual liquid pit 8 in the plant through pipelines.

[0018] The flue gas scrubbing tower 5 is located next to the flue gas spray tower 4 and connected to it via a flue gas pipeline. The scrubbing tower is equipped with two layers of fresh water spray and one layer of wire mesh demister, as well as a spray water pump, pipeline, and valves. The scrubbing tower performs secondary backwashing on the exhaust gas and residual gas of the spray tower.

[0019] The water storage section of the spray and washing tower and the outdoor water supply pipeline are wrapped with electric heating belts, and the tower body is insulated with an aluminum shell to ensure normal water circulation inside the tower in winter.

[0020] The tower body is made of fiberglass reinforced plastic (FRP) and features an integrated tower and tank design, with the bottom of the tower serving as the slurry storage section and the upper part as the washing section. The bottom of the tower is designed with a conical base to facilitate the deposition of particulate matter. The sediment inside the spray tower is cleaned regularly. The spray tower discharges approximately 4 m³ of slurry per day. The slurry containing particulate matter deposited at the bottom of the tower is transported via pipeline to the secondary replacement residual liquid pit 8 within the plant, and then returned to the primary replacement slurry tank by a submersible pump 9.

[0021] The dust removal device for water-containing flue gas during heavy metal smelting can reduce the average particulate matter in the exhaust gas to 5 mg / Nm³. 3 The following fully meet the requirements of the new environmental regulations. The purification efficiency reaches 98%, capable of handling dust particles larger than 0.1μm. Washing sediment can be returned to the system for recycling, with no secondary pollutants generated.

Claims

1. A dust removal device for water-containing flue gas during heavy metal smelting, comprising a flue gas spray tower (4), a spray water pump (6), a flue gas scrubbing tower (5), a backwash pump (7), an exhaust duct (3), a fan (10), and a submersible pump (9), characterized in that: The flue gas spray tower (4) is located outside the smelting furnace plant. It has two layers of spray packing inside, and the spray water pump (6) provides circulating spray slurry to the spray layer. The exhaust pipe (3) is connected to the flue gas hood (2) on the smelting furnace (1) and introduces the dust-laden flue gas into the bottom of the flue gas scrubbing tower (4). After the flue gas is scrubbed, the particulate matter is reduced and the remaining flue gas enters the flue gas scrubbing tower (5). The flue gas scrubbing tower (5) is connected to the flue gas spray tower (4) through a flue gas pipeline. It has two layers of fresh water spray layer and one layer of wire mesh demister layer inside. The backwash pump (7) performs secondary backwashing on the tail gas. The fan (10) is connected to the flue gas scrubbing tower (5) through a pipe, and the purified flue gas is discharged through the chimney. The bottom of the flue gas scrubbing tower (4) is a conical structure and is equipped with pipeline valves for periodically cleaning the deposited slurry containing particulate matter. The slurry is transported through pipelines to the residual liquid pit (8) in the plant. The submersible pump (9) is installed in the pit (8) for recovering valuable metal dust particles.

2. The dust removal device for water-containing flue gas in heavy metal smelting process according to claim 1, characterized in that: The spray water circulation cycle of the spray water pump (6) inside the flue gas spray tower (4) is 48 hours.

3. The dust removal device for water-containing flue gas in heavy metal smelting process according to claim 1, characterized in that: The water storage sections of the spray tower (4) and the washing tower (5) as well as the outdoor water supply pipelines are all wrapped with electric heating belts, and the outer shell of the tower body is insulated with aluminum sheet.

4. The dust removal device for water-containing flue gas in heavy metal smelting process according to claim 1, characterized in that: The spray tower (4) and washing tower (5) are made of fiberglass, with an integrated tower and trough design. The bottom of the tower is a slurry storage section, and the top is a washing section.

5. The dust removal device for water-containing flue gas in heavy metal smelting process according to claim 1, characterized in that: The slurry discharged from the spray tower (4) is transported through pipeline to the secondary replacement residual liquid pit (8), and then returned to the primary replacement slurry tank by the submersible pump (9).

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