Waste gas treatment system

Abstract

The invention discloses a waste gas treatment system. The waste gas treatment system at least comprises a smoke dust treatment system and an oil mist treatment system, the smoke dust treatment system comprises a gas collecting hood, a smoke dust pipeline, a cyclone dust removal device, a bag-type dust remover and a first fan; the gas collecting hood is used for collecting smoke dust and is arranged above a smoke dust / dust generation area, the gas collecting hood is connected with the cyclone dust removal device through a smoke dust pipeline, and the cyclone dust removal device, the bag-type dust remover and the first fan are sequentially connected; the first fan is connected with the first exhaust funnel; the oil mist treatment system comprises an oil mist collecting cover, an oil mist pipeline, a pneumatic rotational flow tower, an electrostatic adsorption device, an activated carbon adsorption device and a second fan, the oil mist collecting cover is connected with the pneumatic rotational flow tower through the oil mist pipeline, the pneumatic rotational flow tower, the electrostatic adsorption device, the activated carbon adsorption device and the second fan are sequentially connected, and the second fan is connected with the second exhaust funnel. According to the invention, various waste gases generated in the production and processing processes of enterprises can be effectively removed.

Description

Technical Field

[0001] The present invention relates to the technical field of waste gas treatment, and in particular to a waste gas treatment system. Background Art

[0002] The production processes involved in the production of enterprises include mechanical processing, aluminum alloy melting, die-casting machine demoulding, shot blasting, etc., which will generate oil mist, smoke from molten aluminum, non-methane total hydrocarbons and other waste gases. According to the corresponding emission standards in the "Comprehensive Emission Standards for Air Pollutants" (DB31 / 933-2015) and the "Emission Standards for Air Pollutants in the Foundry Industry" (GB39726-2020), the waste gases emitted by enterprises must be treated before they can be discharged in compliance with the standards.

[0003] At present, there is no special equipment to remove various waste gases including smoke, oil mist, etc. generated during the production and processing of enterprises. Summary of the invention

[0004] In view of the above problems, the present invention provides an exhaust gas treatment system to solve the problems in the prior art.

[0005] The exhaust gas treatment system is characterized by comprising at least a smoke treatment system and an oil mist treatment system; The smoke treatment system includes an air collecting hood, a smoke pipeline, a cyclone dust removal device, a bag dust collector, and a first fan; the air collecting hood is used to collect smoke and is arranged above the smoke / dust generating area, the air collecting hood is connected to the cyclone dust removal device through the smoke pipeline, the cyclone dust removal device, the bag dust collector, and the first fan are connected in sequence; the first fan is connected to the first exhaust pipe; The oil mist treatment system includes an oil mist collection hood, an oil mist pipeline, a pneumatic cyclone tower, an electrostatic adsorption device, an activated carbon adsorption device, and a second fan. The oil mist collection hood is connected to the pneumatic cyclone tower through the oil mist pipeline. The pneumatic cyclone tower, the electrostatic adsorption device, the activated carbon adsorption device, and the second fan are connected in sequence. The second fan is connected to the second exhaust chimney.

[0006] Preferably, the air collecting hood is a rotary dust collecting hood, and the air inlet of the hood body is provided with rotating blades.

[0007] Preferably, the cyclone dust removal device comprises an air inlet, an air outlet, a gas spiral sinking part, an accelerating spiral sinking part, and a dust outlet. The gas spiral sinking part is a hollow cylinder, the air inlet is arranged on the gas spiral sinking part, the accelerating spiral sinking part is a hollow cone, and the dust outlet is arranged on the accelerating spiral sinking part.

[0008] Preferably, the pneumatic cyclone tower is provided with a water tank, a cyclone layer, a spray layer, and an air outlet assembly from bottom to top; the water in the water tank is pumped to the spray layer by a water pump, the cyclone layer is provided with a gas inlet, and the air outlet assembly is provided with an environmentally friendly filler waterproof layer.

[0009] The smoke and natural gas combustion waste gas generated during the company's production and processing are collected through the gas collection hood. After being treated by the cyclone dust removal device and bag dust collector, the exhaust gas is discharged into the air through the first exhaust pipe.

[0010] The oil mist containing non-methane total hydrocarbons is led to the pneumatic cyclone tower, electrostatic adsorption device, and activated carbon adsorption device through the oil mist pipeline for treatment in sequence, and the exhaust gas is discharged into the air through the second exhaust pipe.

[0011] The waste gas generated by wastewater treatment first enters the alkali washing tower. After being treated by the alkali washing tower, it is successively treated by the pneumatic cyclone tower, the electrostatic adsorption device, and the activated carbon adsorption device. The tail gas is then discharged into the air through the second exhaust pipe.

[0012] The invention can effectively remove various waste gases generated during the production and processing of an enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the exhaust gas treatment system.

[0014] Figure 2 A schematic diagram of the gas hood.

[0015] Figure 3 Schematic diagram of a cyclone dust removal device.

[0016] Figure 4 A partial schematic diagram of the smoke treatment system.

[0017] Figure 5 A partial schematic diagram of the oil mist treatment system.

[0018] Figure 6 Schematic diagram of the pneumatic cyclone tower.

[0019] Figure 7 Schematic diagram of the activated carbon adsorption device. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the implementation methods of the present application, not all of the implementation methods; and the structures shown in the accompanying drawings are only schematic and do not represent physical objects. It should be noted that based on these embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0021] It should be noted that the term "comprises" or any other variant thereof is intended to cover non-exclusive inclusion in this article, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical or equivalent elements in the process, method, article or device including the elements.

[0022] The terms "upper", "lower", "inner", "outer", etc. do not constitute absolute spatial relationship limitations, but are only concepts of relative positions, which can be understood by those skilled in the art.

[0023] See also Figure 1-7 , an exhaust gas treatment system, including a smoke treatment system 100 and an oil mist treatment system 200; The smoke treatment system 100 includes an air collecting hood 110 , a smoke pipeline 120 , a cyclone dust removal device 130 , a bag filter 140 , and a first fan 150 .

[0024] The hood is used to collect smoke and dust. There can be multiple hoods, which are arranged above the smoke / dust generating area (such as melting furnace, holding furnace), such as Figure 2 As shown, the air collecting hood is a rotating dust collection hood, that is, the air inlet of the hood body is provided with rotating blades 111 to accelerate gas suction, and all the air collecting hoods are connected to the cyclone dust collection device 130 through the smoke dust pipeline 120, and the cyclone dust collection device 130, the bag dust collector 140, and the first fan 150 are connected in sequence; the first fan 150 is connected to the first exhaust pipe 160.

[0025] The material of smoke and dust pipeline 120 is 304 stainless steel duct structure, and the whole set includes straight pipe, branch pipe, elbow, connector, pipe clamp, screw, seal and pipe support and fixing materials. It can withstand positive pressure +3000Pa, negative pressure -5000Pa, temperature range -30℃ — +100℃, straight pipe thickness: 1.0~1.2mm, depending on the pipe diameter.

[0026] like Figure 3As shown, the cyclone dust removal device 130 is mainly composed of an air inlet 131, an exhaust port 132, a gas spiral sinking part 133 (hollow cylindrical shape), an accelerating spiral sinking part 134 (cone shape), and a dust outlet 135. After the airflow mixed with dust enters from the air inlet 131, when the gas and dust mixture touches the side wall of the accelerating spiral sinking part, the mixture will rotate clockwise downward along the side wall (the solid line trajectory in the figure). Because the shape of the accelerating spiral sinking part is a cone shape, the gas mixture will accelerate the spiral sinking to the dust outlet 135 in this section. At the dust outlet 135, the dust is thrown out of the cyclone cone (the lower arrow in the figure) under the action of the gas, and the gas will rise along the center line spirally and be discharged from the exhaust port (the dotted line trajectory in the figure).

[0027] The bag filter 140 mainly relies on the filter bag to filter the dusty gas. When the dusty gas passes through the filter bag, the larger particles settle to the bottom due to gravity, while the smaller particles are retained by the filter bag through diffusion and screening, thereby achieving gas purification. A pulse bag filter can be selected, which is an existing structure and will not be described in detail here.

[0028] After the first fan 150 is started, the air flow containing smoke and dust enters the cyclone dust removal device 130 and the bag dust collector 140 from the air collecting hood 110 through the smoke and dust pipeline 120 for dust removal, and then the gas is discharged through the first exhaust pipe 160.

[0029] The oil mist treatment system 200 includes an oil mist collection hood 210, an oil mist pipeline 220, a pneumatic cyclone tower 230, an electrostatic adsorption device 240, an activated carbon adsorption device 250, and a second fan 260. The oil mist collection hood 210 is a square air collecting hood, of which there can be multiple, arranged above the oil mist generating area.

[0030] The oil mist collection hood 210 is connected to the pneumatic cyclone tower 230 through the oil mist pipeline 220. The pneumatic cyclone tower 230, the electrostatic adsorption device 240, the activated carbon adsorption device 250, and the second fan 260 are connected in sequence. The second fan 260 is connected to the second exhaust pipe 270.

[0031] The oil mist pipeline 220 adopts 304 stainless steel duct structure, and the whole set includes straight pipes, branch pipes, elbows, connectors, pipe clamps, screws, seals and pipe support and fixing materials. It can withstand positive pressure +3000Pa, negative pressure -5000Pa, temperature range -30 ℃ — + 100 ℃, straight pipe thickness: 1.0 ~ 1.2 mm, depending on the pipe diameter.

[0032] See also Figure 6The pneumatic cyclone tower 230 is provided with a water tank 231, a cyclone layer 232, a spray layer 233, and an air outlet assembly 234 from bottom to top; the water in the water tank 231 is pumped to the spray layer 233 by a water pump 235, and the cyclone layer 232 is provided with a gas inlet. When the exhaust gas enters the cyclone layer 232 under the traction of the negative pressure fan, the gas is restricted by the inner wall of the tower body, thereby forming a rotating flow state. The exhaust gas, the cyclone and the water falling from the spray layer undergo a gas-liquid emulsification reaction when rotating at high speed, and the exhaust gas and the rotating liquid are fully mixed, and gas-liquid separation is achieved under the action of centrifugal force. The dust particles separated from the exhaust gas sink to the bottom of the water tank. An environmentally friendly filler waterproof layer is provided in the air outlet assembly 234, and the separated gas enters the environmentally friendly filler waterproof layer, and then enters the exhaust gas treatment equipment in the rear section. After treatment, the purification rate can reach more than 95%, and the purified exhaust gas meets the emission requirements and is lower than the national emission standards.

[0033] The equipment can effectively remove water-soluble gases such as hydrogen chloride gas (HCl), hydrogen fluoride gas (HF), ammonia (NH3), sulfuric acid mist (H2SO4), chromic acid mist (CrO3), hydrocyanic acid gas (HCN), alkali vapor (NaOH), hydrogen sulfide gas (H2S), and formalin (HCHO).

[0034] The electrostatic adsorption device 240 ionizes the gas molecules in the air through a high-voltage electrostatic field, generating a large number of negative ions and positive ions. Under the action of the electric field force, these ions move toward the two poles and collide with the dust particles in the air to charge them. The charged dust particles move toward the electrodes with opposite polarity under the action of the electric field force and are eventually adsorbed on the electrodes, thereby achieving the dust removal effect. The device is changed to a conventional dust removal device and will not be described in detail here.

[0035] See also Figure 7 The activated carbon adsorption device 250 includes a tank body 251, and the two ends of the tank body 251 are provided with an inlet and outlet (252, 253). An activated carbon adsorption plate device 254 is arranged inside the tank body. The activated carbon adsorption plate device 254 uses activated carbon with a large specific surface area and high adsorption performance as an adsorbent to adsorb atmospheric pollutants in organic waste gas and discharge clean air.

[0036] The mechanism of activated carbon adsorption treatment of waste gas mainly includes physical adsorption and chemical adsorption: Physical adsorption mainly occurs in the process of activated carbon removing impurities in the liquid and gas phases. The porous structure of activated carbon provides a large surface area, making it very easy to absorb and collect impurities. Since there are unbalanced and unsaturated molecular attractions or chemical bonds on the surface of activated carbon adsorbents, when this solid surface comes into contact with gas, it can attract gas molecules, concentrate them and keep them on the solid surface. This phenomenon is called adsorption. By utilizing the adsorption capacity of the solid surface, the exhaust gas is brought into contact with a porous solid substance with a large surface area, and the pollutants in the exhaust gas are adsorbed on the solid surface, separating them from the gas mixture to achieve the purpose of purification.

[0037] In addition to physical adsorption, chemical reactions often occur on the surface of activated carbon. Activated carbon contains not only carbon, but also a small amount of chemically bound oxygen and nitrogen in the form of functional groups on its surface, such as hydroxyl, hydroxyl, phenols, lactones, quinones, ethers, etc. These oxides or complexes on the surface can react chemically with the adsorbed substances, thereby combining with the adsorbed substances and aggregating on the surface of the activated carbon.

[0038] In addition, the waste gas treatment system also includes an alkali washing tower 300, the inlet of the alkali washing tower 300 is connected to the gas collecting hood of the wastewater treatment station, and the outlet of the alkali washing tower 300 is connected to the air inlet of the pneumatic cyclone tower 230. The waste gas generated by the wastewater treatment first enters the alkali washing tower 300, and after being treated by the alkali washing tower, it is led to the pneumatic cyclone tower 230 and the activated carbon adsorption device 250, and the exhaust gas is discharged into the air through the second exhaust pipe 270.

[0039] After the particulate pollutants in the air flow come into contact with the washing liquid, the droplets or liquid film diffuse and attach to the air flow particles, or humidify the particles, so that the particles can be separated and removed by gravity, inertia, etc. The gaseous pollutants are transported into the washing liquid by mass transfer such as turbulence, molecular diffusion, and chemical reactions to achieve the purpose of separation from the incoming gas. Chemical substances can also be added to the washing liquid to control gaseous odor substances by absorption. The equipment itself includes the main body, packing layer, demisting layer, circulating sprinkler pipeline, and circulating water tank.

[0040] The waste gas passes through the alkaline washing tower 300 and is treated by gas-liquid reverse absorption, that is, the liquid is sprayed from the top of the tower downward in the form of mist (or small water droplets), and the waste gas reaches the purpose of gas-liquid contact from the bottom of the tower (reverse flow). This treatment method can cool the waste gas temperature, regulate the gas, and remove particles. It is then discharged into the atmosphere after being treated in the demisting section.

[0041] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. An exhaust gas treatment system, characterized in that: At least including smoke treatment system and oil mist treatment system; The smoke treatment system includes an air collecting hood, a smoke pipeline, a cyclone dust removal device, a bag dust collector, and a first fan; the air collecting hood is used to collect smoke and is arranged above the smoke / dust generating area, the air collecting hood is connected to the cyclone dust removal device through the smoke pipeline, the cyclone dust removal device, the bag dust collector, and the first fan are connected in sequence; the first fan is connected to the first exhaust pipe; The oil mist treatment system includes an oil mist collection hood, an oil mist pipeline, a pneumatic cyclone tower, an electrostatic adsorption device, an activated carbon adsorption device, and a second fan. The oil mist collection hood is connected to the pneumatic cyclone tower through the oil mist pipeline. The pneumatic cyclone tower, the electrostatic adsorption device, the activated carbon adsorption device, and the second fan are connected in sequence. The second fan is connected to the second exhaust chimney.

2. The exhaust gas treatment system according to claim 1, characterized in that: The air collecting hood is a rotary dust collecting hood, and the air inlet of the hood body is provided with rotary blades.

3. The exhaust gas treatment system according to claim 1, characterized in that: The cyclone dust removal device comprises an air inlet, an air outlet, a gas spiral sinking part, an accelerating spiral sinking part, and a dust outlet. The gas spiral sinking part is a hollow cylinder, the air inlet is arranged on the gas spiral sinking part, the accelerating spiral sinking part is a hollow cone, and the dust outlet is arranged on the accelerating spiral sinking part.

4. The exhaust gas treatment system according to claim 1, characterized in that: The pneumatic cyclone tower is provided with a water tank, a cyclone layer, a spray layer, and an air outlet assembly from bottom to top; the water in the water tank is pumped to the spray layer by a water pump, the cyclone layer is provided with a gas inlet, and the air outlet assembly is provided with an environmentally friendly filler waterproof layer.

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