Multi-stage treatment system for industrial waste gas

Abstract

The utility model relates to the technical field of environmental protection equipment, in particular to an industrial waste gas multistage treatment system which comprises a plurality of waste gas washing towers which are sequentially connected through pipelines, a gas inlet of the first waste gas washing tower is connected with an ozone injection device, and a gas outlet of the last waste gas washing tower is connected with an exhaust chimney. And each waste gas washing tower is connected with a medicine circulating supply device. Compared with the prior art, the casting waste gas treatment device is high in safety performance, low in investment, small in size and light in weight, and ozone of the ozone injection device is chemically reacted with casting waste gas to partially oxidize and decompose the casting waste gas into non-toxic and odorless substances; then the casting waste gas enters a plurality of waste gas washing towers in sequence, the casting waste gas is in full contact with medicaments from bottom to top for gas-liquid mass transfer, organic matters and peculiar smell molecules in the casting waste gas are effectively removed through unconsumed ozone in different absorption liquids and circulating spray liquids, and the effect is remarkable.

Description

Technical Field

[0001] This utility model relates to the field of environmental protection equipment technology, specifically to a multi-stage industrial waste gas treatment system. Background Technology

[0002] Currently, most casting processes, especially the casting of engine cylinder heads, often require sand core forming. Because the sand cores are heated and vaporized during forming and casting, a certain amount of flue gas is generated. Improper treatment of this flue gas can pollute the workshop environment, affecting workers' health, and also cause pollution to the surrounding environment. The flue gas mainly contains formaldehyde, phenol, and aromatic compounds such as benzene, toluene, and styrene, which are odorous gases. Current common treatment methods include adsorption, absorption, and combustion. Simple absorption has low purification efficiency and is not suitable for use alone. The temperature of the flue gas from core forming is higher than room temperature, making adsorption unsuitable. Catalytic combustion and regenerative direct combustion methods have high investment and operating costs and are not suitable for treating low-concentration organic waste gases. Utility Model Content

[0003] To overcome the shortcomings of the above-mentioned technical defects, this utility model provides a multi-stage industrial waste gas treatment system, which has a better deodorization effect on odorous waste gases of various components generated during the core making, casting and cooling processes.

[0004] The purpose of this invention is to provide a multi-stage industrial waste gas treatment system. The key features include multiple waste gas scrubbing towers connected sequentially by pipelines. The inlet of the first waste gas scrubbing tower is connected to an ozone injection device, and the outlet of the last waste gas scrubbing tower is connected to an exhaust chimney. Each waste gas scrubbing tower is connected to a chemical circulation supply device. This solution premixes the foundry waste gas with ozone, partially oxidizing and decomposing it into non-toxic and odorless substances before sequentially introducing it into the multiple waste gas scrubbing towers. The foundry waste gas undergoes gas-liquid mass transfer through full contact with the chemical agents flowing from bottom to top. Furthermore, any unconsumed ozone at the front end is absorbed into the circulating spray liquid, further oxidizing organic matter and odor molecules in the waste gas.

[0005] Furthermore, the waste gas scrubbing tower comprises three units, and the drug circulation supply device comprises three units, which respectively supply sodium hydroxide solution, hydrogen peroxide solution, and plant extract. This scheme, by selecting three different absorbents, enables rapid polymerization, substitution, displacement, and adsorption of various harmful and odorous molecules, adsorbing them onto various waste gases. This alters the original structure of pollutant gas and odor molecules, transforming them into non-toxic and odorless molecules, thereby improving the waste gas treatment capacity.

[0006] Furthermore, the waste gas scrubbing tower includes a tower body with multiple packing layers arranged from top to bottom. Spray pipes are provided between adjacent packing layers. An air outlet is located at the top of the tower body, an air inlet is located at the bottom, and a liquid storage area is located at the bottom. Both the liquid storage area and the spray pipes are connected to the drug circulation supply device. Specifically, the spray pipes spray absorbent liquid into the packing layers. The casting waste gas rising from the bottom and the reagent flowing from the top come into full contact with each other in the packing layers, achieving gas-liquid mass transfer and realizing dual treatment of absorption and adsorption of harmful substances in the waste gas.

[0007] In a more preferred embodiment, a high-performance atomizing nozzle is installed on the spray pipe, so that the absorbent liquid forms a thin mist after entering the air, thereby increasing the gas-liquid contact area.

[0008] Furthermore, the tower body is also provided with a demister packing layer, which is located between the uppermost packing layer and the gas outlet. Specifically, when the flue gas comes into contact with the demister packing layer, the droplets and particles therein are captured, while the gas passes through the demister packing layer and is discharged from the gas outlet.

[0009] Furthermore, the drug circulation supply device includes a circulating water tank, a drug tank, and a submersible pump installed in the circulating water tank. The submersible pump is connected to the corresponding spray pipeline. The drug tank is connected to the circulating water tank pipeline via a dosing pump. The circulating water tank is connected to the corresponding storage area via a return pipe. Specifically, unconsumed ozone is absorbed into the circulating spray liquid, continuously further oxidizing organic matter and odor molecules in the waste gas.

[0010] Furthermore, the circulating water tank is equipped with a pH sensor and an ORP sensor. Specifically, a pH sensor is installed in the circulating water tank supplying sodium hydroxide solution, and an ORP sensor is installed in the circulating water tank supplying hydrogen peroxide solution, to control the dosing pump to dosing the chemicals and maintain a certain concentration of the absorbent in the circulating water tank.

[0011] Furthermore, the ozone injection device includes an ozone generator and an induced draft fan connected by pipelines, and the induced draft fan is connected to the air inlet of the first waste gas scrubbing tower via a pipeline. This design allows the waste gas to be partially oxidized and decomposed into non-toxic and odorless substances by ozone before entering the waste gas scrubbing tower.

[0012] Furthermore, multiple inspection windows are provided on the side wall of the tower body, each corresponding to a different packing layer. This design allows for regular inspection of the packing layers within the tower body through these inspection windows.

[0013] Beneficial Effects: This utility model provides a multi-stage industrial waste gas treatment system with high safety performance, low investment, small size, and light weight. Ozone from the ozone injection device reacts chemically with the foundry waste gas, partially oxidizing and decomposing it into non-toxic and odorless substances. The waste gas then sequentially enters multiple waste gas scrubbing towers, where it comes into full contact with the top-down reagents for gas-liquid mass transfer. Through the unconsumed ozone in different absorbent liquids and the circulating spray liquid, the organic matter and odor molecules in the foundry waste gas are effectively removed, resulting in significant effectiveness. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the structure of a waste gas scrubbing tower. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present utility model are only used to explain the relative positional relationship and movement of the components in a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. In addition, the descriptions involving "first", "second", etc. in the present utility model are only used for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" and "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0017] Please see Figure 1This utility model provides a multi-stage industrial waste gas treatment system, comprising multiple waste gas scrubbing towers 1 connected sequentially by pipelines. The inlet of the first waste gas scrubbing tower 1 is connected to an ozone injection device 2, and the outlet of the last waste gas scrubbing tower 1 is connected to an exhaust chimney 3. Each waste gas scrubbing tower 1 is connected to a drug circulation supply device 4. This scheme premixes the foundry waste gas with ozone, partially oxidizing and decomposing it into non-toxic and odorless substances before sequentially entering the multiple waste gas scrubbing towers. The foundry waste gas undergoes gas-liquid mass transfer through full contact with the drug from bottom to top, and any unconsumed ozone at the front end is absorbed into the circulating spray liquid, further oxidizing organic matter and odor molecules in the waste gas.

[0018] In one specific embodiment, there are three waste gas scrubbing towers 1 and three drug circulation supply devices 4, which respectively supply sodium hydroxide solution, hydrogen peroxide solution, and plant extract. This scheme, by selecting three different absorbents, can rapidly undergo chemical reactions such as polymerization, substitution, displacement, and adsorption with various harmful and odorous molecules, adsorbing various waste gases and altering the original structure of pollutant gas and odor molecules, transforming them into non-toxic and odorless molecules, thereby improving the waste gas treatment capacity.

[0019] Please see Figure 2 In one specific embodiment, the waste gas scrubbing tower 1 includes a tower body 11, with multiple packing layers 12 arranged from top to bottom in the tower body 11. Spray pipes 13 are provided between adjacent packing layers 12. An air outlet 15 is provided at the top of the tower body 11, an air inlet 16 is provided at the bottom of the tower body 11, and a liquid storage area 14 is provided at the bottom of the tower body 11. Both the liquid storage area 14 and the spray pipes 13 are connected to the drug circulation supply device 4. To ensure the efficiency of the spray tower, the height of the packing layers is 0.8-1.1m, the inner diameter of the tower body is 0.6-0.8m, the empty tower gas velocity reaches 1.5m / s, and the gas-liquid ratio reaches 2.5L / m³. 3 During the treatment process, the spray pipe sprays the absorbent liquid into the packing layer. The casting waste gas from bottom to top and the reagent from top to bottom come into full contact in the packing layer to carry out gas-liquid mass transfer, realizing the dual treatment of absorption and adsorption of harmful substances in the waste gas.

[0020] In one specific embodiment, the filler layer 12 includes a horizontally arranged grid plate and filler placed on the grid plate. The filler can be a material such as ceramic, PP or PE. In a more preferred embodiment, the filler is a polypropylene hollow sphere with a porosity of 0.65-0.95.

[0021] In one specific embodiment, a high-performance atomizing nozzle is installed on the spray pipe, so that the absorbent liquid enters the air and forms a thin mist, thereby increasing the gas-liquid contact area.

[0022] In one specific embodiment, the tower body 11 is further provided with a demisting packing layer 17, which is located between the uppermost packing layer 12 and the air outlet 15; when the flue gas comes into contact with the demisting packing layer, the droplets and particles therein are captured, while the gas passes through the demisting packing layer and is discharged from the air outlet.

[0023] In one specific embodiment, the demisting filler layer 17 includes a horizontally arranged grid plate and a demisting filler placed on the grid plate. The filler can be a material such as ceramic, PP or PE. In a more preferred embodiment, the PP filler is a porous ceramic ball with a porosity of 0.45-0.55.

[0024] In one specific embodiment, the drug circulation supply device 4 includes a circulating water tank 41, a medicine tank 42, and a submersible pump 43 installed in the circulating water tank 41. The submersible pump 43 is connected to the corresponding spray pipeline 13. The medicine tank 42 is connected to the circulating water tank 41 via a dosing pump 44. The circulating water tank 41 is connected to the corresponding liquid storage area 14 via a return pipe 44. The submersible pump continuously introduces the absorbent liquid into the scrubbing tower to circulate and absorb the waste gas in the tower. Unconsumed ozone is absorbed into the circulating spray liquid, continuously further oxidizing the organic matter and odor molecules in the waste gas.

[0025] In one specific embodiment, a pH sensor 5 is installed in the circulating water tank supplying sodium hydroxide solution. The pH sensor 5 monitors the pH value of the reagent in the circulating water tank and controls the dosing pump to add the reagent through the controller, so as to maintain a certain concentration of sodium hydroxide solution in the circulating water tank.

[0026] In one specific embodiment, an ORP sensor 6 is installed in the circulating water tank supplying hydrogen peroxide solution. The ORP sensor 6 monitors the ORP value of the agent in the circulating water tank and controls the dosing pump to add the agent through the controller, so as to maintain a certain concentration of hydrogen peroxide solution in the circulating water tank.

[0027] In one specific embodiment, the air inlet of the first exhaust gas scrubbing tower 1 is connected to a main blower via an air inlet pipe; the ozone injection device 2 includes an ozone generator 21 and an induced draft fan 22 connected by a pipeline, and the induced draft fan 22 is connected to the air inlet pipe; the exhaust gas is premixed with ozone before entering the exhaust gas scrubbing tower, and the exhaust gas is partially oxidized and decomposed into non-toxic and odorless substances by ozone in advance.

[0028] In one specific embodiment, a plurality of inspection windows 7 are provided on the side wall of the tower body 11, and the inspection windows 7 correspond one-to-one with each packing layer 12; the packing layers in the tower body are periodically inspected through each inspection window.

[0029] The present invention will be further described below with reference to a specific application scenario:

[0030] A multi-stage industrial waste gas treatment system includes three waste gas scrubbing towers 1 connected sequentially by pipes. The inlet of the first waste gas scrubbing tower 1 is connected to a main blower 8 and an ozone injection device 2 via an air inlet pipe. The ozone injection device 2 includes an ozone generator 21 and an induced draft fan 22 connected by pipes. The induced draft fan 22 is connected to the air inlet pipe. The outlet of the last waste gas scrubbing tower 1 is connected to an exhaust chimney 3. Each waste gas scrubbing tower 1 is connected to a drug circulation supply device 4, which supplies sodium hydroxide solution, hydrogen peroxide solution, and plant extract, respectively. Each waste gas scrubbing tower 1 includes a tower body 11, in which three packing layers 12 and a demisting packing layer 17 are arranged from top to bottom. The demisting packing layer 17 is located between the uppermost packing layer 12 and the outlet 15. Multiple inspection windows 7 are provided on the side wall of the tower body 11. Each packing layer 12 corresponds to a separate packing layer 12. Spray pipes 13 are provided between adjacent packing layers 12. High-performance atomizing nozzles 131 are installed on the spray pipes 13. An air outlet 15 is provided at the top of the tower body 11, and an air inlet 16 is provided at the bottom of the tower body 11. A liquid storage area 14 is provided at the bottom of the tower body 11. The liquid storage area 14 and the spray pipes 13 are both connected to the drug circulation supply device 4. The drug circulation supply device 4 includes a circulating water tank 41, a medicine tank 42, and a submersible pump 43 installed in the circulating water tank 41. The submersible pump 43 is connected to the corresponding spray pipe 13. The medicine tank 42 is connected to the circulating water tank 41 through a dosing pump 44. The circulating water tank 41 is connected to the corresponding liquid storage area 14 through a return pipe 44. A pH sensor 5 is installed in the circulating water tank supplying sodium hydroxide solution, and an ORP sensor 6 is installed in the circulating water tank supplying hydrogen peroxide solution.

[0031] Working principle: The foundry waste gas is mixed with ozone generated by the ozone injection device 2 and then introduced into the waste gas scrubbing tower 1 through the main blower 8. The waste gas is introduced into the three waste gas scrubbing towers in sequence, and the waste gas is fully contacted with the top-down reagents in each tower for gas-liquid mass transfer. The three different reagents in the three waste gas scrubbing towers react rapidly with various harmful and odorous molecules in the waste gas through polymerization, substitution, displacement, and adsorption. Finally, the waste gas is transformed into a non-toxic and odorless gas and is discharged from the exhaust chimney 3.

[0032] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model. Those skilled in the art can make various similar representations under the guidance of the present utility model without departing from the spirit and claims of the present utility model, and such modifications all fall within the protection scope of the present utility model.

Claims

1. A multi-stage industrial waste gas treatment system, characterized in that: It includes multiple exhaust gas scrubbing towers (1) connected in sequence by pipes. The inlet of the first exhaust gas scrubbing tower (1) is connected to an ozone injection device (2), and the outlet of the last exhaust gas scrubbing tower (1) is connected to an exhaust chimney (3). Each exhaust gas scrubbing tower (1) is connected to a drug circulation supply device (4). The waste gas scrubbing tower (1) includes a tower body (11), in which multiple packing layers (12) are provided from top to bottom, and spray pipes (13) are provided between adjacent packing layers (12). An air outlet (15) is provided at the top of the tower body (11), an air inlet (16) is provided at the bottom of the tower body (11), and a liquid storage area (14) is provided at the bottom of the tower body (11). The liquid storage area (14) and the spray pipes (13) are both connected to the drug circulation supply device (4). The drug circulation supply device (4) includes a circulating water tank (41), a medicine tank (42), and a submersible pump (43) installed in the circulating water tank (41). The submersible pump (43) is connected to the corresponding spray pipeline (13). The medicine tank (42) is connected to the circulating water tank (41) through a dosing pump (44). The circulating water tank (41) is connected to the corresponding liquid storage area (14) through a return pipe (45).

2. The multi-stage industrial waste gas treatment system according to claim 1, characterized in that: There are three waste gas scrubbing towers (1) and three drug circulation supply devices (4). The three drug circulation supply devices (4) supply sodium hydroxide solution, hydrogen peroxide solution and plant extract, respectively.

3. The multi-stage industrial waste gas treatment system according to claim 1, characterized in that: The tower body (11) is also provided with a demisting packing layer (17), which is located between the uppermost packing layer (12) and the air outlet (15).

4. The multi-stage industrial waste gas treatment system according to claim 1, characterized in that: The circulating water tank (41) is equipped with a pH sensor (5) and an ORP sensor (6).

5. The multi-stage industrial waste gas treatment system according to claim 1, characterized in that: The ozone injection device (2) includes an ozone generator (21) and an induced draft fan (22) connected by a pipeline. The induced draft fan (22) is connected to the air inlet of the first exhaust gas scrubbing tower (1) through a pipeline.

6. The multi-stage industrial waste gas treatment system according to claim 3, characterized in that: Multiple inspection windows (7) are provided on the side wall of the tower body (11), and each inspection window (7) corresponds to one of the packing layers (12).

Images