Waste gas treatment system

Abstract

The utility model discloses a waste gas treatment system which 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 utility model, various waste gases generated in the production and processing processes of enterprises can be effectively removed.

Description

TECHNICAL FIELD

[0001] The utility model relates to waste gas treatment technical field, especially waste gas treatment system. BACKGROUND

[0002] The production processes such as machining, aluminum alloy melting, die casting machine demolding and shot blasting machine shot blasting involved in enterprise production process will produce oil mist, smoke dust generated by molten aluminum and non-methane total hydrocarbon waste gas. According to the corresponding emission standard in “Integrated Emission Standard of Air Pollutants” (DB31 / 933-2015) and “Casting Industry Air Pollutant Emission Standard” (GB39726-2020), the waste gas discharged by enterprises must be treated to meet the emission standard.

[0003] At present, there is no special equipment to remove various waste gases such as smoke dust and oil mist generated in the production and processing process of enterprises. UTILITY MODEL CONTENT

[0004] In view of the above problems, the utility model provides a waste gas treatment system to solve the problems in the prior art.

[0005] The waste gas treatment system comprises at least a smoke dust treatment system and an oil mist treatment system.

[0006] The smoke dust treatment system comprises a gas collecting hood, a smoke dust pipeline, a cyclone dust removal device, a bag-type dust collector and a first fan.

[0007] The oil mist treatment system comprises an oil mist collecting hood, an oil mist pipeline, a pneumatic cyclone tower, an electrostatic adsorption device, an activated carbon adsorption device and a second fan.

[0008] Preferably, the gas collecting hood is a rotary dust collecting hood, and the gas inlet of the hood body is provided with rotary blades.

[0009] Preferably, the cyclone dust removal device comprises a gas inlet, an exhaust port, a gas spiral sinking part, an accelerated spiral sinking part and a dust outlet.

[0010] Preferably, the pneumatic cyclone tower is sequentially provided with a water tank, a cyclone layer, a spraying layer and an air outlet assembly from bottom to top; water in the water tank is pumped to the spraying layer, the cyclone layer is provided with a gas inlet, and the air outlet assembly is provided with an environmental protection filler water-proof layer.

[0011] The smoke dust generated in the production and processing process of the enterprise and the natural gas combustion exhaust gas are collected through the gas collecting hood, treated through the cyclone dust removal device and the bag-type dust collector, and then discharged through the first exhaust pipe at high altitude.

[0012] The oil mist containing non-methane total hydrocarbon is introduced to the pneumatic cyclone tower, the electrostatic adsorption device and the activated carbon adsorption device through the oil mist pipeline for treatment, and then discharged through the second exhaust pipe at high altitude.

[0013] The exhaust gas generated in the wastewater treatment is first introduced into the alkali washing tower, treated through the alkali washing tower, and then treated through the pneumatic cyclone tower, the electrostatic adsorption device and the activated carbon adsorption device, and then discharged through the second exhaust pipe at high altitude.

[0014] The utility model can effectively remove various exhaust gases generated in the production and processing process of the enterprise. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a schematic view of the exhaust gas treatment system.

[0016] Figure 2 It is a schematic view of the gas collecting hood.

[0017] Figure 3 It is a schematic view of the cyclone dust removal device.

[0018] Figure 4 It is a partial schematic view of the smoke dust treatment system.

[0019] Figure 5 It is a partial schematic view of the oil mist treatment system.

[0020] Figure 6 It is a schematic view of the pneumatic cyclone tower.

[0021] Figure 7 It is a schematic view of the activated carbon adsorption device. DETAILED DESCRIPTION

[0022] The technical scheme of the utility model will be described below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the application, not all the embodiments; and the structure shown in the drawings is only schematic, not the actual object. It should be noted that all other embodiments obtained by those skilled in the art based on these embodiments in the utility model belong to the scope of protection of the application.

[0023] It has to be understood that the term "comprising" or any other variant thereof, as used in the context of this document, is intended to cover also the case where the process, method, article or apparatus includes additional steps, elements, features or components not expressly listed or shown. In other words, it is intended that the term "comprising" or any other variant thereof, as used in the context of this document, does not exclude other elements or steps. It is further intended to cover the case where additional steps, elements, features or components are added to the process, method, article or apparatus.

[0024] The terms "upper", "lower", "inner", "outer" and the like do not denote an absolute spatial relationship, but are merely a relative position concept, which is understood by the skilled person.

[0025] Referring to Figures 1-7 , the exhaust gas treatment system comprises a smoke treatment system 100 and an oil mist treatment system 200;

[0026] The smoke treatment system 100 comprises a hood 110, a smoke pipeline 120, a cyclone dust collector 130, a bag-type dust collector 140 and a first fan 150.

[0027] The hood is used to collect smoke and can be multiple, arranged above the smoke / dust generating area (such as melting furnace, holding furnace), as shown in Figure 2 The hood is a rotating dust hood, i.e. the air inlet of the hood body is provided with rotating blades 111 to accelerate the gas suction. All the hoods are connected with the cyclone dust collector 130 through the smoke pipeline 120, and the cyclone dust collector 130, the bag-type dust collector 140 and the first fan 150 are connected in sequence. The first fan 150 is connected with a first exhaust cylinder 160.

[0028] The material of the smoke pipeline 120 adopts 304 stainless steel air pipe structure, which includes straight pipe, branch pipe, elbow, connecting piece, pipe clamp, screw, sealing and pipe supporting and fixing material. It can withstand positive pressure +3000Pa, negative pressure -5000Pa, temperature range -30℃ — +100℃, straight pipe thickness: 1.0-1.2mm, depending on the size of the pipe diameter.

[0029] As shown in Figure 3As shown, the cyclone dust removal device 130 mainly consists of an air inlet 131, an air outlet 132, a gas spiral descending part 133 (hollow cylindrical shape), an accelerated spiral descending part 134 (frustum shape), and a dust outlet 135. After the airflow mixed with dust enters the air inlet 131, when the gas and dust mixture touches the sidewall of the accelerated spiral descending part, the mixture will rotate clockwise downward along the sidewall (the solid line trajectory in the figure). Because the shape of the accelerated spiral descending part is a frustum, the gas mixture will be accelerated and spirally descend to the dust outlet 135. At the dust outlet 135, the dust is thrown out of the cyclone cone under the action of the gas (the lower arrow in the figure), and the gas will spirally rise along the center line and be discharged from the air outlet (the dashed line trajectory in the figure).

[0030] The bag filter 140 mainly relies on the filter bag to filter the dust-containing gas. When the dust-containing gas passes through the filter bag, larger particles will settle to the bottom due to gravity, and smaller particles will be trapped by the filter bag through diffusion and screening, thereby achieving gas purification. A pulse bag filter can be selected. The device is of the existing structure, and will not be described in detail here.

[0031] After the first fan 150 is started, the airflow containing smoke dust enters the cyclone dust removal device 130 and the bag filter 140 from the gas hood 110 through the smoke dust pipeline 120 for dust removal treatment, and then the gas is discharged through the first air outlet cylinder 160.

[0032] 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 gas hood and can have multiple ones arranged above the oil mist generation area.

[0033] 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 air outlet cylinder 270.

[0034] The oil mist pipeline 220 adopts a 304 stainless steel air pipe structure, which includes straight pipes, branch pipes, elbows, connecting pieces, pipe clamps, screws, seals, and pipeline support and fixing materials. It can withstand a positive pressure of +3000 Pa, a negative pressure of -5000 Pa, a temperature range of -30 ℃ to +100 ℃, and a straight pipe thickness of 1.0-1.2 mm, which depends on the size of the pipe diameter.

[0035] Referring to Figure 6The pneumatic cyclone tower 230 is sequentially provided with a water tank 231, a cyclone layer 232, a spraying layer 233 and an air outlet assembly 234 from bottom to top. Water in the water tank 231 is pumped to the spraying layer 233 by a water pump 235. 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 limited by the inner wall of the tower body, thereby forming a rotating flow state. The exhaust gas, cyclone and water falling from the spraying layer are subjected to gas-liquid emulsification reaction in high-speed rotation, and the exhaust gas and the rotating liquid are fully mixed and separated under the action of centrifugal force. The dust particles separated from the exhaust gas sink to the bottom of the water tank. The air outlet assembly 234 is provided with an environmental protection filler water barrier. The separated gas enters the environmental protection filler water barrier 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 standard.

[0036] The device can effectively remove water-soluble gases such as hydrogen chloride gas (HCl), hydrogen fluoride gas (HF), ammonia gas (NH3), sulfuric acid mist (H2SO4), chromic acid mist (CrO3), cyanogen acid gas (HCN), alkali vapor (NaOH), hydrogen sulfide gas (H2S) and formaldehyde (HCHO).

[0037] The electrostatic adsorption device 240 ionizes the gas molecules in the air through a high-voltage electrostatic field to generate a large number of negative ions and positive ions. Under the action of the electric field force, these ions move towards the two poles and collide with the dust particles in the air to charge them. The charged dust particles move towards the electrodes with opposite polarity under the action of the electric field force and are finally adsorbed on the electrodes, thereby achieving the effect of dust removal. The device is a conventional dust removal device, which will not be described in detail here.

[0038] Referring to Figure 7 The activated carbon adsorption device 250 includes a tank body 251 provided with an inlet and an outlet (252, 253) at both ends, and an activated carbon adsorption plate device 254 arranged inside the tank body,

[0039] 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 pollution components in the organic exhaust gas and discharge clean air.

[0040] The mechanism of the activated carbon adsorption treatment of exhaust gas mainly includes physical adsorption and chemical adsorption:

[0041] Physical adsorption occurs mainly in the process of removing impurities in liquid and gas phases by activated carbon. The porous structure of activated carbon provides a large surface area, so it is very easy to achieve the purpose of absorbing and collecting impurities. Because there are unbalanced and unsaturated molecular attraction or chemical bond forces on the surface of activated carbon adsorbent, when the solid surface is in contact with gas, it can attract gas molecules, concentrate and keep them on the solid surface, which is called adsorption. By using the adsorption capacity of the solid surface, the pollutants in the waste gas are adsorbed on the surface of the solid, so as to separate them from the gas mixture and achieve the purpose of purification.

[0042] In addition to physical adsorption, chemical reactions often occur on the surface of activated carbon. Activated carbon not only contains carbon, but also contains a small amount of oxygen and nitrogen in the form of functional groups such as hydroxyl, hydroxyl, phenolic, lactone, quinone, ether, etc. on its surface. These surface-contained oxides or complexes can chemically react with the adsorbed substances, thereby combining with the adsorbed substances and gathering on the surface of activated carbon.

[0043] In addition, the waste gas treatment system also includes an alkali washing tower 300, the inlet of the alkali washing tower 300 is connected with the gas hood of the waste water treatment station, the outlet of the alkali washing tower 300 is connected with the gas inlet of the pneumatic cyclone tower 230, the waste gas generated by the waste water treatment first enters the alkali washing tower 300, and then is introduced into the pneumatic cyclone tower 230 and the activated carbon adsorption device 250 after being treated by the alkali washing tower. The tail gas is discharged at a high altitude through the second exhaust pipe 270.

[0044] After the particulate pollutants in the gas flow come into contact with the scrubbing liquid, the droplets or liquid films diffuse and adhere to the gas flow particles, or the particles are humidified, so that the particles are separated and removed by gravity, inertial force and other effects. Gaseous pollutants are transferred into the scrubbing liquid by mass transfer such as turbulence, molecular diffusion and chemical reaction, so as to separate from the inlet gas. Chemical substances can be added to the scrubbing liquid to control gaseous odor substances by absorption. The equipment itself includes a body, a filler layer, a demisting layer, a circulating sprinkler pipeline, and a circulating water tank, etc.

[0045] The waste gas is treated by the alkali washing tower 300 in a gas-liquid reverse absorption mode, that is, the liquid is sprayed in the form of mist (or small water droplets) from the top of the tower downward, and the waste gas is from the bottom (reverse flow) to achieve the purpose of gas-liquid contact. This treatment method can cool the waste gas temperature, gas conditioning, and particle removal. After the demisting section, the exhaust gas is discharged into the atmosphere.

[0046] The basic principle, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection required by the present application is defined by the appended claims and their equivalents.

Claims

1. An exhaust gas treatment system, characterized by, At least comprising 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 collector and a first fan; the gas collecting hood is used to collect smoke dust and is arranged above a smoke dust / powder generating area; the gas collecting hood is connected with the cyclone dust removal device through the smoke dust pipeline; the cyclone dust removal device, the bag-type dust collector and the first fan are connected in sequence; the first fan is connected with a first exhaust cylinder. The oil mist treatment system comprises an oil mist collecting 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 collecting hood is connected with 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 with a second exhaust cylinder.

2. The exhaust treatment system of claim 1, wherein, The gas collecting hood is a rotary dust collecting hood, and a rotary blade is arranged at an air inlet of the hood body.

3. The exhaust treatment system of claim 1, wherein, The cyclone dust removal device comprises an air inlet, an air outlet, a gas spiral sinking part, an accelerated spiral sinking part and a dust outlet; the gas spiral sinking part is a hollow cylinder, the air inlet is arranged at the gas spiral sinking part, the accelerated spiral sinking part is a hollow frustum, and the dust outlet is arranged at the accelerated spiral sinking part.

4. The exhaust treatment system of claim 1, wherein, The pneumatic cyclone tower is sequentially provided with a water tank, a cyclone layer, a spraying layer and an air outlet assembly from bottom to top; water in the water tank is pumped to the spraying layer by a water pump; the cyclone layer is provided with a gas inlet; and the air outlet assembly is provided with an environmental protection filler water-proof layer.

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