Polluted gas treatment device for polyurethane waterproof coating production and treatment method thereof

Abstract

The invention provides a pollution gas treatment device for polyurethane waterproof coating production and a treatment method thereof, and relates to the technical field of gas treatment.The pollution gas treatment device comprises a dry adsorption spray tower, the dry adsorption spray tower is provided with a treatment mechanism facilitating multi-stage treatment of gas, and the dry adsorption spray tower is provided with a gas inlet and a gas outlet. The treatment mechanism comprises a spiral diffusion plate, an adsorbent ejector, an interception chamber, a plasma generator and a wet-type adsorption spray tower, the spiral diffusion plate and the adsorbent ejector are both located on the inner side wall of the dry-type adsorption spray tower, and the interception chamber is located at the side end of the dry-type adsorption spray tower. According to the device, the plasma generator is arranged, after residual pollutants, such as free isocyanate, amine intermediates, free radicals and the like, of the dry adsorption spray tower enter the plasma generator, the plasma can decompose precursors in a short time aiming at pollutants difficult to degrade and the specific easy polymerization characteristic of polyurethane waste gas in the process, and therefore the degradation rate of the waste gas is improved. And the risk of secondary polymerization after entering the wet tower is blocked.

Description

Technical Field

[0001] This invention belongs to the field of gas treatment technology, and more specifically, relates to a polluted gas treatment device and treatment method for the production of polyurethane waterproof coatings. Background Technology

[0002] The production of polyurethane coatings generates polluting gases. During resin synthesis, coating formulation, viscosity adjustment, or inadequate sealing of production equipment, venting of reaction vessels, and heating during the curing process, residual monomers and decomposition products are released, leading to waste gas generation. The composition of these polluting gases is complex, typically consisting of a mixture primarily composed of isocyanates and VOCs, supplemented by ammonia, amines, and particulate matter.

[0003] The Chinese patent publication number is CN114870605B, which discloses a treatment device for removing chemical pollutants from the atmospheric environment. This invention uses a spraying mechanism installed inside a chemical spraying tower to separate and guide the gas and allow it to fully mix and contact with the degradation liquid, thereby improving the degradation effect.

[0004] Existing polyurethane waterproof coatings have the following disadvantages when used for waste gas treatment: The single treatment process leads to clogging problems: Traditional polyurethane waterproof coating exhaust gas treatment mostly adopts a single wet process. Due to the complex composition of polyurethane exhaust gas, the isocyanate in it will instantly generate polyurea when it comes into contact with water, which can easily cause blockage of pipes and fillers. This blockage will not only reduce the operating efficiency of exhaust gas treatment equipment, but may even cause the equipment to fail to operate normally in severe cases, requiring frequent shutdowns for cleaning, increasing maintenance costs and the risk of production interruption.

[0005] Adsorption efficiency and cost issues: Existing waste gas treatment methods have low gas-solid contact time and gas-solid mixing efficiency in the adsorption treatment of pollutants such as isocyanates in polyurethane waste gas. This results in poor capture effect of adsorbents on pollutants in waste gas, low utilization rate of adsorbents, and thus high consumption costs of adsorbents such as zeolite powder.

[0006] Difficult-to-degrade pollutants are difficult to treat: Polyurethane waste gas contains pollutants such as free isocyanates and amine intermediates that are difficult to degrade and have the characteristic of easy polymerization. This makes it easy for secondary polymerization to occur during subsequent treatment, affecting the overall treatment effect and making it difficult for the emitted waste gas to meet environmental protection standards. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a pollutant gas treatment device and method for the production of polyurethane waterproof coatings, thereby resolving the problems described above.

[0008] A polluted gas treatment device for polyurethane waterproof coating production includes a dry adsorption spray tower. The dry adsorption spray tower is equipped with a treatment mechanism for multi-stage gas treatment. The treatment mechanism includes a spiral diffuser plate, an adsorbent injector, an interception chamber, a plasma generator, and a wet adsorption spray tower. The spiral diffuser plate and adsorbent injector are located on the inner wall of the dry adsorption spray tower. The interception chamber is located at the side end of the dry adsorption spray tower, and the plasma generator is located at the side end of the interception chamber. A temperature control device is fixedly installed between the interception chamber and the plasma generator. The wet adsorption spray tower is located at the side end of the plasma generator. A waste gas inlet pipe is fixedly installed at the lower end of the dry adsorption spray tower, and a waste gas guide is fixedly installed at the upper end of the dry adsorption spray tower. The dry adsorption spray tower has a swirling mixing chamber on its inner wall, located in the middle section of the inner wall. A spiral diffuser plate is fixedly installed on the inner wall of the dry adsorption spray tower, located at the upper end of the exhaust gas inlet pipe. An adsorbent feeding pipe is fixedly installed through the upper end of the dry adsorption spray tower. An adsorbent injector is fixedly installed at the lower end of the adsorbent feeding pipe. A dry tower support is fixedly installed at the circumferential end of the dry adsorption spray tower. An interception chamber is fixedly installed at the side end of the exhaust gas guide pipe. An interception filter is provided on the inner wall of the interception chamber. A recovery chamber is fixedly installed at the lower end of the interception chamber. A control panel is provided at the side end of the plasma generator, and a connecting pipe is also provided at the side end of the plasma generator.

[0009] Preferably, an air inlet pipe is fixedly installed at the circumferential end of the wet adsorption spray tower, and an air supply pipe is fixedly installed between the plasma generator and the air inlet pipe.

[0010] Preferably, the wet adsorption spray tower has a circulating water tank at its circumferential end, and the port at the upper end of the wet adsorption spray tower is connected to a gas-liquid separation device.

[0011] A method for treating polluted gases used in the production of polyurethane waterproof coatings, comprising the following steps: S1: Gas is introduced into the dry adsorption spray tower through the exhaust gas inlet pipe. When the exhaust gas passes through the spiral diffuser, the forced airflow increases its tangential velocity and rotates. The adsorbent injector sprays zeolite powder. The polluted gas at the bottom passes through the turbulent field formed by the spiral diffuser. The isocyanate molecules in the exhaust gas are efficiently captured by the zeolite powder. At the same time, trace amounts of moisture trigger a preliminary hydrolysis reaction on the surface of the hydrophobic zeolite. S2: The gas can be introduced into the interception chamber from the exhaust gas duct. The interception chamber is equipped with an interception filter, which will intercept the saturated zeolite powder and collect it in the recovery chamber. The exhaust gas carries the residual pollutants into the next stage. S3: The gas that has completed the initial dry adsorption in the dry adsorption spray tower will enter the plasma generator. The high-energy particles of the plasma generator will bombard the gas to achieve molecular-level cracking. In response to the easy polymerization characteristics of polyurethane waste gas, the plasma can decompose the precursors in a short time and block the risk of secondary polymerization after entering the wet tower. S4: After the gas finally enters the wet adsorption spray tower, the waste gas treated in the first two stages enters the tower body. The fragmented pollutants generated by the plasma are rapidly adsorbed and undergo catalytic hydrolysis. The end of the wet adsorption spray tower is connected to the gas-liquid separator. After being treated by the gas-liquid separator, the isocyanate concentration is reduced, meeting the emission standards for waste gas treatment.

[0012] Compared with the prior art, the present invention has the following beneficial effects: In this invention, a dry adsorption spray tower 1 is added before the wet adsorption spray tower 4. Modified zeolite powder with low water content is used to pre-adsorb and initially react isocyanate molecules in polyurethane waste gas. This avoids the problem in traditional single wet process where isocyanate reacts with water to instantly generate polyurea and clog pipes and packings. In the initial stage of the reaction, isocyanate molecules in the waste gas are efficiently captured by zeolite powder. At the same time, trace amounts of moisture trigger a preliminary hydrolysis reaction on the surface of hydrophobic zeolite, which can effectively avoid clogging caused by direct wet spraying and improve the treatment efficiency of waste gas.

[0013] In this invention, an adsorbent injector 15 is installed at the top of the dry adsorption spray tower 1, and an exhaust gas inlet pipe 11 is installed at the bottom. This ensures that the polluted gas and the zeolite powder sprayed by the adsorbent injector 15 move in opposite directions, thereby guaranteeing the gas-solid contact time and the efficiency of gas-solid mixing. Fresh adsorbent first contacts the low-concentration exhaust gas, and saturated adsorbent contacts the high-concentration zone. Furthermore, the adsorbent flows from top to bottom, which can wash the tower wall, reduce polyurea adhesion, improve adsorbent utilization, and reduce zeolite powder consumption costs.

[0014] In this invention, a spiral diffuser plate 14 is installed at the bottom of the dry adsorption spray tower 1 to force the airflow to increase its tangential velocity and rotate. The rotating flow field enters the swirl mixing chamber 13 to achieve efficient mixing with zeolite powder, thereby strengthening gas-solid contact, ensuring the efficient capture and hydrolysis reaction of polluted waste gas by the dry adsorbent, and improving the treatment efficiency and separation effect of polluted gas.

[0015] In this invention, residual pollutants such as free isocyanates, amine intermediates, and free radicals in the dry adsorption spray tower 1 are introduced into the plasma generator 3. Under the action of high-voltage pulses, molecular bonds are broken in a directional manner. Isocyanates are bombarded into free radicals by high-energy electrons, and amines are oxidized by hydroxyl free radicals. This process can target pollutants that are difficult to degrade. In response to the easy polymerization characteristics of polyurethane waste gas, the plasma can decompose the precursors in a short time, blocking the risk of secondary polymerization after entering the wet tower.

[0016] In this invention, a series of steps are employed, including a dry adsorption spray tower 1, a plasma generator 3, and a wet adsorption spray tower 4, to progressively weaken pollutants. The fragmented molecules after plasma treatment are efficiently hydrolyzed and mineralized by a spiral diffuser plate 14, and then discharged after meeting emission standards. The efficient matching of the dry adsorption spray tower 1, plasma generator 3, and wet adsorption spray tower 4 avoids the problems of incomplete adsorption and clogging that can occur with single treatments, thus ensuring efficient treatment of polyurethane waste gas while reducing energy consumption. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the dry adsorption spray tower of the present invention; Figure 2 This is a schematic diagram of the interception chamber of the present invention; Figure 3 This is an exploded structural diagram of the dry adsorption spray tower of the present invention; Figure 4 This is a schematic cross-sectional view of the dry adsorption spray tower of the present invention. Figure 5 This is a schematic diagram of the structure of the adsorbent feeding tube of the present invention; Figure 6 This is an exploded structural diagram of the interception chamber of the present invention; Figure 7 This is a schematic diagram of the structure of the plasma generator of the present invention; Figure 8 This is a schematic diagram of the structure of the wet adsorption spray tower of the present invention.

[0018] In the diagram, the correspondence between component names and attached drawing numbers is as follows: 1. Dry adsorption spray tower; 11. Exhaust gas inlet pipe; 12. Exhaust gas guide pipe; 13. Swirl mixing chamber; 14. Spiral diffuser plate; 15. Adsorbent injector; 16. Adsorbent feeding pipe; 17. Dry tower support; 2. Interception chamber; 21. Recovery chamber; 22. Interception filter; 3. Plasma generator; 31. Control panel; 32. Temperature control equipment; 33. Connecting pipe; 4. Wet adsorption spray tower; 41. Inlet receiving pipe; 42. Gas transmission pipe; 43. Circulating water tank. Detailed Implementation

[0019] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0020] Please see Figure 1 - Figure 8 This invention provides a pollutant gas treatment device for the production of polyurethane waterproof coatings, including a dry adsorption spray tower 1. The dry adsorption spray tower 1 is equipped with a treatment mechanism to facilitate multi-stage gas treatment. Pollutant gases are generated during the production of polyurethane coatings. During the resin synthesis stage, during coating formulation and viscosity adjustment, or due to inadequate sealing of production equipment, exhaust from the reactor, and heating during the curing process, residual monomers and decomposition products are released, leading to the generation of waste gas. The composition of these pollutant gases is complex, typically consisting of isocyanates and VOCs as the main components, supplemented by ammonia, amines, and particulate matter. Therefore, it is necessary to treat the waste gas generated at the end of the polyurethane coating production process. The waste gas is introduced into the dry adsorption spray tower 1 through the waste gas inlet pipe 11, where it is initially captured and separated by mixing with the adsorbent. Then, it enters the plasma generator 3 through the waste gas guide pipe 12 for component decomposition, and finally enters the wet adsorption spray tower 4 for spray treatment. The treatment mechanism includes a spiral diffuser plate 14, an adsorbent injector 15, an interception chamber 2, a plasma generator 3, and a wet adsorption spray tower 4. The spiral diffuser plate 14 and the adsorbent injector 15 are both located on the inner wall of the dry adsorption spray tower 1. The interception chamber 2 is located at the side end of the dry adsorption spray tower 1, and the plasma generator 3 is located at the side end of the interception chamber 2. A temperature control device 32 is fixedly installed between the interception chamber 2 and the plasma generator 3. The wet adsorption spray tower 4 is located at the side end of the plasma generator 3. A waste gas inlet pipe 11 is fixedly installed at the lower end of the dry adsorption spray tower 1, and a waste gas guide pipe 12 is fixedly installed at the upper end of the dry adsorption spray tower 1. A swirl mixing chamber 13 is provided on the inner wall of the dry adsorption spray tower 1, located in the middle section of the inner wall of the dry adsorption spray tower 1. A spiral diffuser plate 14 is fixedly installed on the inner wall of the dry adsorption spray tower 1, located at the upper end of the waste gas inlet pipe 11. An adsorbent is fixedly installed through the upper end of the dry adsorption spray tower 1. The feed pipe 16 and the adsorbent injector 15 are fixedly installed at the lower end of the adsorbent feed pipe 16. A dry tower support 17 is fixedly installed at the circumferential end of the dry adsorption spray tower 1. When performing preliminary treatment on the exhaust gas of polyurethane coating, the gas can be introduced into the dry adsorption spray tower 1 through the exhaust gas inlet pipe 11. A spiral diffuser plate 14 is installed on the inner side wall of the dry adsorption spray tower 1, that is, at the inlet end of the exhaust gas inlet pipe 11. When the exhaust gas enters, the forced airflow increases its shear rate as it passes through the spiral diffuser plate 14. The column rotates at a speed, and the adsorbent particles move toward the tower wall through centrifugal force. An adsorbent injector 15 is set at the top. Dry adsorbent, such as zeolite powder, can be added into the adsorbent injector 15 through the adsorbent feeding pipe 16. The polluted gas at the bottom passes through the turbulent field formed by the spiral diffuser 14. The isocyanate molecules in the waste gas are efficiently captured by the zeolite powder. At the same time, trace amounts of moisture trigger a preliminary hydrolysis reaction on the surface of the hydrophobic zeolite. This process can remove some isocyanates and intercept some VOCs. The interception chamber 2 is fixedly installed at the side end of the exhaust gas duct 12. The inner wall of the interception chamber 2 is provided with an interception filter 22. The lower end of the interception chamber 2 is fixedly installed with a recovery chamber 21. Gas can be introduced into the interception chamber 2 from the exhaust gas duct 12. The interception filter 22 in the interception chamber 2 will intercept the saturated zeolite powder and collect it in the recovery chamber 21. The exhaust gas carries the residual pollutants into the next stage. The side end of the plasma generator 3 is equipped with a control panel 31 and a connecting pipe 33. The gas that has completed the initial dry adsorption in the dry adsorption spray tower 1 will enter the plasma generator 3. The values ​​of the plasma generator 3 can be set through the control panel 31 and the temperature can be detected through the connecting pipe 33. The residual pollutants in the gas discharged from the dry adsorption spray tower 1 are decomposed at the molecular level by the high-energy particles bombarded by the plasma generator 3. After the waste gas enters the dielectric barrier discharge reaction chamber in the plasma generator 3, the nanosecond-level high-voltage pulse ionizes the gas, generating a large number of high-energy electrons and active free radicals. These active substances precisely bombard free isocyanates, amine intermediates and VOCs molecules, causing them to decompose into small molecular fragments and decompose polyurea precursors, further helping to avoid blockage of the downstream wet tower. The gas temperature can be monitored through the connecting pipe 33 to prevent local gas overheating. The gas after the plasma reaction will finally enter the spiral diffuser plate 14. An inlet pipe 41 is fixedly installed at the circumferential end of the wet adsorption spray tower 4. A gas supply pipe 42 is fixedly installed between the plasma generator 3 and the inlet pipe 41. A circulating water tank 43 is provided at the circumferential end of the wet adsorption spray tower 4. The port at the upper end of the wet adsorption spray tower 4 is connected to a gas-liquid separation device. After the gas finally enters the wet adsorption spray tower 4, the waste gas treated by the first two stages enters the tower body and comes into countercurrent contact with the nano CeO2 catalytic alkaline solution sprayed by the ultrasonic atomizing nozzle at the top of the tower. The fragmented pollutants generated by the plasma are rapidly adsorbed and undergo catalytic hydrolysis reaction. Amines are converted into NH3 and alcohols, and residual VOCs are oxidized into CO2 and H2O. The end of the wet adsorption spray tower 4 is connected to the gas-liquid separator. After treatment by the gas-liquid separator, the isocyanate concentration is reduced, meeting the emission standards for waste gas treatment.

[0021] Working principle: The first step involves the generation of polluting gases during the polyurethane coating production process. During resin synthesis, coating formulation, viscosity adjustment, or inadequate sealing of production equipment, reactor exhaust, and heating during the curing process, residual monomers and decomposition products are released, leading to waste gas generation. This waste gas is complex, primarily composed of isocyanates and VOCs, supplemented by ammonia, amines, and particulate matter—a typical mixed waste gas. Therefore, it is necessary to treat the waste gas generated at the end of the polyurethane coating production process. The waste gas is introduced into a dry adsorption spray tower 1 through the waste gas inlet pipe 11, where it undergoes preliminary capture and separation by mixing with the adsorbent. It then enters the plasma generator 3 through the waste gas guide pipe 12 for component decomposition, and finally enters the wet adsorption spray tower 4 for spray treatment.

[0022] In the second step, during the preliminary treatment of the exhaust gas from the polyurethane coating, the gas can be introduced into the dry adsorption spray tower 1 through the exhaust gas inlet pipe 11. A spiral diffuser plate 14 is installed on the inner wall of the dry adsorption spray tower 1, at the inlet end of the exhaust gas inlet pipe 11. When the incoming exhaust gas passes through the spiral diffuser plate 14, the forced airflow increases its tangential velocity, causing it to rotate. This centrifugal force then causes the adsorbent particles to move towards the tower wall. An adsorbent injector 15 is installed at the top, and dry adsorbent can be added to the adsorbent injector 15 through the adsorbent feeding pipe 16. Additives, such as zeolite powder, are used to force pollutants from the bottom of the gas to pass through the turbulent flow field formed by the spiral diffuser plate 14. Isocyanate molecules in the exhaust gas are efficiently captured by the zeolite powder. At the same time, trace amounts of moisture trigger a preliminary hydrolysis reaction on the surface of the hydrophobic zeolite. This process can remove some isocyanates and intercept some VOCs. The gas can be introduced into the interception chamber 2 from the exhaust gas guide pipe 12. The interception chamber 2 is equipped with an interception filter 22, which will intercept the saturated zeolite powder and collect it in the recovery chamber 21. The exhaust gas carries the residual pollutants into the next stage. This device incorporates a dry adsorption spray tower 1, installed before the wet adsorption spray tower 4. It utilizes modified zeolite powder with low moisture content to pre-adsorb and initially react isocyanate molecules in polyurethane waste gas. This avoids the problem in traditional single wet processes where isocyanate reacts instantly with water to form polyurea, clogging pipes and packing. In the initial stage of the reaction, isocyanate molecules in the waste gas are efficiently captured by the zeolite powder. Simultaneously, trace amounts of moisture trigger a preliminary hydrolysis reaction on the hydrophobic zeolite surface, effectively preventing clogging caused by direct wet spraying and improving waste gas treatment efficiency. This device has an adsorbent injector 15 at the top of the dry adsorption spray tower 1 and an exhaust gas inlet pipe 11 at the bottom, so that the polluted gas and the zeolite powder sprayed by the adsorbent injector 15 are in relative motion directions, thereby ensuring the gas-solid contact time and the gas-solid mixing efficiency. Fresh adsorbent first comes into contact with low-concentration exhaust gas, and saturated adsorbent comes into contact with high-concentration zone. In addition, the adsorbent flows from top to bottom, which can wash the tower wall, reduce polyurea adhesion, improve adsorbent utilization rate, and reduce zeolite powder consumption cost. This device uses a spiral diffuser plate 14 installed at the bottom of the dry adsorption spray tower 1 to force the airflow to increase its tangential velocity and rotate. The rotating flow field enters the swirl mixing chamber 13 and can achieve efficient mixing with zeolite powder, thereby strengthening gas-solid contact, ensuring the efficient capture and hydrolysis reaction of polluted waste gas by the dry adsorbent, and improving the treatment efficiency and separation effect of polluted gas. The third step involves the gas undergoing preliminary dry adsorption in the dry adsorption spray tower 1 entering the plasma generator 3. The values ​​of the plasma generator 3 can be set via the control panel 31, and the temperature can be monitored via the connecting pipe 33. Residual pollutants in the gas discharged from the dry adsorption spray tower 1 are subjected to molecular-level decomposition by high-energy particle bombardment in the plasma generator 3. After the waste gas enters the dielectric barrier discharge reaction chamber in the plasma generator 3, the nanosecond-level high-voltage pulse ionizes the gas, generating a large number of high-energy electrons and active free radicals. These active substances precisely bombard free isocyanates, amine intermediates, and VOCs molecules, causing them to decompose into small molecule fragments and decompose polyurea precursors, further helping to prevent blockage of the downstream wet tower. The gas temperature can be monitored via the connecting pipe 33 to prevent local gas overheating. The gas that has undergone the plasma reaction will finally enter the spiral diffuser plate 14. This device incorporates a plasma generator 3. Residual pollutants from the dry adsorption spray tower 1, such as free isocyanates, amine intermediates, and free radicals, enter the plasma generator 3. Under the action of high-voltage pulses, molecular bonds undergo directional breakage. Isocyanates are bombarded by high-energy electrons into free radicals, and amines are oxidized by hydroxyl free radicals. This process is effective against recalcitrant pollutants and addresses the unique polymerization characteristics of polyurethane waste gas. The plasma can decompose precursors in a short time, preventing the risk of secondary polymerization after entering the wet tower. In the fourth step, after the gas finally enters the wet adsorption spray tower 4, the waste gas treated in the first two stages enters the tower body and comes into countercurrent contact with the nano CeO2 catalytic alkaline solution sprayed by the ultrasonic atomizing nozzle at the top of the tower. The fragmented pollutants generated by the plasma are rapidly adsorbed and undergo catalytic hydrolysis reaction. Amines are converted into NH3 and alcohols, and residual VOCs are oxidized into CO2 and H2O. The end of the wet adsorption spray tower 4 is connected to the gas-liquid separator. After being treated by the gas-liquid separator, the isocyanate concentration is reduced, meeting the emission standards for waste gas treatment. This device employs a combination of a dry adsorption spray tower 1, a plasma generator 3, and a wet adsorption spray tower 4 to create a progressively weakening treatment process for pollutants. The spiral diffuser 14 efficiently hydrolyzes and mineralizes the fragmented molecules after plasma treatment, ensuring compliance with emission standards before discharge. The efficient matching of the dry adsorption spray tower 1, plasma generator 3, and wet adsorption spray tower 4 avoids incomplete adsorption and clogging issues that can occur with single-processor systems, thus reducing energy consumption while ensuring efficient treatment of polyurethane waste gas.

[0023] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A polluted gas treatment device for the production of polyurethane waterproof coatings, comprising a dry adsorption spray tower (1), characterized in that: The dry adsorption spray tower (1) is equipped with a treatment mechanism that facilitates multi-stage treatment of gas; The processing mechanism includes a spiral diffuser plate (14), an adsorbent injector (15), an interception chamber (2), a plasma generator (3), and a wet adsorption spray tower (4). The spiral diffuser plate (14) and the adsorbent injector (15) are located on the inner wall of the dry adsorption spray tower (1). The interception chamber (2) is located at the side end of the dry adsorption spray tower (1). The plasma generator (3) is located at the side end of the interception chamber (2). A temperature control device (32) is fixedly installed between the interception chamber (2) and the plasma generator (3). The wet adsorption spray tower (4) is located at the side end of the plasma generator (3).

2. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 1, characterized in that, The lower end of the dry adsorption spray tower (1) is fixedly installed with a waste gas inlet pipe (11), and the upper end of the dry adsorption spray tower (1) is fixedly installed with a waste gas guide pipe (12).

3. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 2, characterized in that, The inner wall of the dry adsorption spray tower (1) is provided with a swirling mixing chamber (13), which is located in the middle section of the inner wall of the dry adsorption spray tower (1).

4. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 3, characterized in that, The spiral diffuser plate (14) is fixedly installed on the inner wall of the dry adsorption spray tower (1), and the spiral diffuser plate (14) is located at the upper end of the exhaust gas inlet pipe (11).

5. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 4, characterized in that, The upper end of the dry adsorption spray tower (1) is fixedly installed with an adsorbent feeding pipe (16), the adsorbent injector (15) is fixedly installed at the lower end of the adsorbent feeding pipe (16), and the circumferential end of the dry adsorption spray tower (1) is fixedly installed with a dry tower support (17).

6. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 5, characterized in that, The interception chamber (2) is fixedly installed at the side end of the exhaust gas duct (12). The inner wall of the interception chamber (2) is provided with an interception filter (22). The lower end of the interception chamber (2) is fixedly installed with a recovery chamber (21).

7. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 6, characterized in that, The plasma generator (3) is provided with a control panel (31) at its side end, and a connecting pipe (33) is also provided at its side end.

8. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 7, characterized in that, The wet adsorption spray tower (4) is fixedly installed with an air inlet pipe (41) at its circumferential end, and an air supply pipe (42) is fixedly installed between the plasma generator (3) and the air inlet pipe (41).

9. The polluted gas treatment device for polyurethane waterproof coating production as described in claim 8, characterized in that, The wet adsorption spray tower (4) is provided with a circulating water tank (43) at its circumferential end, and the port at the upper end of the wet adsorption spray tower (4) is connected to a gas-liquid separation device.

10. A method for treating polluted gases used in the production of polyurethane waterproof coatings, characterized in that, The steps are as follows: S1: Gas is introduced into the dry adsorption spray tower (1) through the exhaust gas inlet pipe (11). When the exhaust gas passes through the spiral diffuser plate (14), the forced airflow increases its tangential velocity and rotates. The adsorbent injector (15) sprays zeolite powder. The polluted gas at the bottom passes through the turbulent field formed by the spiral diffuser plate (14). The isocyanate molecules in the exhaust gas are efficiently captured by the zeolite powder. At the same time, a small amount of water triggers a preliminary hydrolysis reaction on the surface of the hydrophobic zeolite. S2: Gas can be introduced into the interception chamber (2) from the exhaust gas duct (12). An interception filter (22) is installed in the interception chamber (2) to intercept the saturated zeolite powder and collect it in the recovery chamber (21). The exhaust gas carries the residual pollutants into the next stage. S3: The gas that has completed the initial dry adsorption in the dry adsorption spray tower (1) will enter the plasma generator (3). The high-energy particles of the plasma generator (3) will bombard the gas to achieve molecular-level cracking. In view of the easy polymerization characteristics of polyurethane waste gas, the plasma can decompose the precursor in a short time and block the risk of secondary polymerization after entering the wet tower. S4: After the gas finally enters the wet adsorption spray tower (4), the waste gas treated by the first two stages enters the tower body. The fragmented pollutants generated by the plasma are rapidly adsorbed and undergo catalytic hydrolysis. The end of the wet adsorption spray tower (4) is connected to the gas-liquid separator. After being treated by the gas-liquid separator, the isocyanate concentration decreases and meets the emission standards for waste gas treatment.

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