Plastic uptake waste gas treatment device and waste gas treatment method
By designing a vacuum forming waste gas treatment device with cylindrical spray heads and a hole cleaning mechanism, the problem of spray head clogging was solved, the stability of the spraying effect and the continuity of production were achieved, and the operation and maintenance costs were reduced.
Patent Information
- Application Number
- CN202511962731.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-24
- Publication Date
- 2026-04-21
AI Technical Summary
During the treatment of vacuum forming exhaust gas, the spray heads are prone to clogging, which affects the stable operation of the alkali washing tower, leading to production continuity problems and increasing operation and maintenance costs.
Design a vacuum forming waste gas treatment device, which adopts a cylindrical spray head and a hole cleaning mechanism. The spray hole is cleaned periodically by a drive mechanism, and the spraying effect is ensured by reverse spraying neutralization reaction.
It effectively prevents spray head clogging, ensures the continuity and efficiency of vacuum forming waste gas treatment, and reduces operation and maintenance costs.
Smart Images
Figure CN121891907A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of waste gas treatment technology, and in particular to a device and method for treating waste gas from thermoforming. Background Technology
[0002] Vacuum forming is widely used in the production of plastic packaging, automotive interiors, and other products. Its core process involves heating plastic sheets to soften them and then shaping them. This process generates a mixed waste gas containing volatile organic compounds, acidic gases, and small amounts of oil mist and dust. To achieve compliant emissions, the industry commonly employs a combination of alkaline scrubbing pretreatment and end-of-pipe treatment. The alkaline scrubbing tower, as the core pretreatment equipment, primarily functions to neutralize acidic components in the waste gas through alkaline spraying and to intercept some oil mist and dust, providing stable air intake conditions for subsequent end-of-pipe treatment. The spray head, as a key component of the alkaline scrubbing tower, directly determines the contact area and reaction efficiency between the alkaline solution and the waste gas, making it crucial for ensuring effective pretreatment. In practical applications, spray heads are prone to clogging after prolonged operation, severely impacting the stable operation of the alkaline scrubbing tower. When the acidic components in the blister packaging exhaust gas come into contact with the alkaline solution, a neutralization reaction occurs. The resulting salts easily deposit and crystallize on the inner walls of the spray nozzles. Simultaneously, plasticizer mist and fine dust carried by the exhaust gas adhere to the surface of the spray nozzles, intertwining with the salt crystals and gradually reducing the flow area of the nozzles, ultimately leading to nozzle blockage. Blockage not only causes uneven alkaline spraying and reduces the neutralization efficiency of the acidic gases, but also disrupts the airflow distribution within the alkaline scrubbing tower, increasing equipment operating resistance and forcing the production line to shut down for disassembly, cleaning, or replacement of the spray nozzles. This affects production continuity and increases equipment maintenance costs, becoming a key bottleneck restricting the long-term stable operation of blister packaging exhaust gas treatment systems. Summary of the Invention
[0003] Based on the technical problems existing in the background art, the present invention proposes a vacuum forming waste gas treatment device and waste gas treatment method.
[0004] The present invention proposes a vacuum forming exhaust gas treatment device, including an exhaust gas treatment tower. An installation plate and a working plate are installed inside the exhaust gas treatment tower. A water storage cavity is formed between the installation plate and the working plate. An installation hole is opened through the working plate. A cylindrical spray head is slidably installed in the installation hole. An annular groove communicating with the water storage cavity is opened on the cylindrical spray head. A spray hole communicating with the annular groove is opened on the outer periphery of the cylindrical spray head. The cylindrical spray head is equipped with a hole cleaning mechanism, which is used to clean the dirt inside the spray hole. A drive mechanism is mounted on the mounting plate, which is used to drive the cylindrical spray head to extend and retract within the mounting hole.
[0005] Preferably, the hole cleaning mechanism includes a hole cleaning rod and an ejection assembly; the cylindrical spray head has a receiving hole that slides with the hole cleaning rod, and one end of the cylindrical spray head can be inserted into the spray hole and block the spray hole; The ejector assembly is used to drive the end of the cleaning rod into the injection hole.
[0006] Preferably, the ejection assembly includes a gradient drive rod and a retraction spring; the gradient drive rod is fixedly mounted on the mounting plate, the cylindrical spray head has an ejection groove that slides with the gradient drive rod, and the end of the cleaning rod slides with the side of the gradient drive rod. The cleaning rod has a boss on its outer circumference, and the cylindrical spray head has a recessed groove that slides with the boss. The recessed spring is located in the recessed groove, and the two ends of the recessed spring abut against the inner wall of the end of the boss and the recessed groove, respectively.
[0007] Preferably, the driving mechanism includes an electric push rod and a mounting bracket; the number of cylindrical spray heads is multiple, and each of the multiple cylindrical spray heads is connected to a mounting bracket, the mounting bracket is fixedly mounted on the output shaft of the electric push rod, and the electric push rod is mounted on a mounting plate.
[0008] Preferably, the working plate is provided with a guiding mechanism; when the cylindrical spray head slides in the mounting hole, the guiding mechanism can guide the cylindrical spray head to rotate.
[0009] Preferably, the guiding mechanism includes a sliding shaft; the sliding shaft is fixedly installed on the inner wall of the mounting hole, and the outer periphery of the cylindrical spray head is provided with a spiral groove that slides with the sliding shaft.
[0010] Preferably, a plurality of through pipes are installed through the mounting plate, and the end of the through pipe away from the mounting plate passes through the working plate.
[0011] Preferably, the waste gas treatment tower is connected to an air inlet pipe, the top of the waste gas treatment tower is connected to an exhaust pipe, and the waste gas treatment tower is also equipped with a liquid inlet pipe connected to a water storage chamber.
[0012] A method for treating vacuum forming exhaust gas, comprising the following steps: S1. Pre-treatment and collection of exhaust gas; S2, Precise preparation of spray alkaline solution; S3, reverse spray neutralization reaction.
[0013] Preferably, the vacuum forming exhaust gas is first mixed with the alkaline solution sprayed from the spray holes on the outer periphery of the cylindrical spray head, and then passed through the through pipe.
[0014] The present invention provides a vacuum forming exhaust gas treatment device and method with the following beneficial effects: through the exhaust gas treatment tower, mounting plate, working plate, cylindrical spray head, cleaning mechanism and driving mechanism, the spray holes on the cylindrical spray head can be cleaned regularly, and the dirt on the outer periphery of the cylindrical spray head can be cleaned at the same time, avoiding the accumulation of dirt and causing the spray holes to be blocked, thereby ensuring the treatment effect of vacuum forming exhaust gas spray. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the overall structure of a vacuum forming exhaust gas treatment device proposed in this invention; Figure 2 This is a cross-sectional view of a vacuum forming exhaust gas treatment device proposed in this invention; Figure 3 This is a top view of the through pipe on the mounting plate in a vacuum forming exhaust gas treatment device proposed in this invention; Figure 4 This invention provides a device for treating vacuum forming exhaust gas. Figure 2 Enlarged view of point A in the middle; Figure 5 This is a schematic diagram showing the position of the cleaning rod relative to the cylindrical spray head during the cleaning process in a vacuum forming exhaust gas treatment device proposed in this invention; Figure 6 This is a schematic diagram showing the positions of the cleaning rod and the cylindrical spray head during spraying operations in a vacuum forming exhaust gas treatment device proposed in this invention. Figure 7 This is a schematic diagram of the gradient drive rod in a vacuum forming waste gas treatment device proposed in this invention.
[0016] In the diagram: 1. Waste gas treatment tower; 2. Mounting plate; 3. Working plate; 4. Water storage chamber; 5. Cylindrical spray head; 6. Annular groove; 7. Orifice cleaning rod; 8. Gradient drive rod; 9. Retraction spring; 10. Electric push rod; 11. Mounting bracket; 12. Sliding shaft; 13. Spiral chute; 14. Air inlet pipe; 15. Exhaust pipe; 16. Liquid inlet pipe; 17. Through pipe. Detailed Implementation
[0017] Reference Figures 1-7This invention proposes a vacuum forming exhaust gas treatment device, including an exhaust gas treatment tower 1. An installation plate 2 and a working plate 3 are installed inside the exhaust gas treatment tower 1. A water storage cavity 4 is formed between the installation plate 2 and the working plate 3. An installation hole is formed through the working plate 3, and a cylindrical spray head 5 is slidably installed in the installation hole. An annular groove 6 communicating with the water storage cavity 4 is formed on the cylindrical spray head 5, and spray holes communicating with the annular groove 6 are formed on the outer periphery of the cylindrical spray head 5. A cleaning mechanism is installed on the cylindrical spray head 5 to clean the dirt inside the spray holes. A driving mechanism is installed on the installation plate 2 to drive the cylindrical spray head 5 to extend and retract within the installation hole. In actual use… In the process, the alkaline solution enters the water storage chamber 4, and then enters the spray hole through the annular groove 6 and is sprayed out. However, after a long period of use, the inner wall of the spray hole and the outer periphery of the cylindrical spray head 5 will have deposits, crystals, oil mist, dust and other substances adhering to it, which will gradually cause the opening of the spray hole to become smaller, thus affecting the effect of spraying to treat the plastic forming waste gas. The dirt in the spray hole is cleaned out by the hole cleaning mechanism, and then the cylindrical spray head 5 is driven to retract into the mounting hole of the working plate 3. The working plate 3 scrapes the dirt adhering to the outer periphery of the cylindrical spray head 5 to achieve a comprehensive cleaning effect, reduce the clogging of the spray hole due to long-term use, and ensure the effect of spraying to treat the plastic forming waste gas.
[0018] like Figure 4 , Figure 5 and Figure 6 As shown, the hole cleaning mechanism includes a hole cleaning rod 7 and an ejector assembly; a cylindrical spray head 5 has a receiving hole that slides with the hole cleaning rod 7, and one end of the cylindrical spray head 5 can be inserted into the spray hole and block the spray hole. The ejector assembly is used to drive the end of the hole cleaning rod 7 into the spray hole. During normal use, the end of the hole cleaning rod 7 is located in the annular groove 6 (see...). Figure 6 The spray nozzle is in the open state to ensure that the alkaline solution can be sprayed out and mixed with the vacuum forming exhaust gas; during the cleaning process, the cleaning rod 7 is pushed into the spray nozzle by the ejector assembly, and the end of the cleaning rod 7 is inserted into the spray nozzle to push out the dirt on the inner wall of the spray nozzle (see...). Figure 5 The end of the cleaning rod 7 coincides with the outer periphery of the cylindrical spray head 5, ensuring that the dirt on its outer periphery is cleaned when the cylindrical spray head 5 is retracted.
[0019] like Figure 4 , Figure 5 and Figure 6As shown, the ejection assembly includes a gradient drive rod 8 and a retraction spring 9. The gradient drive rod 8 is fixedly mounted on the mounting plate 2. The cylindrical spray head 5 has an ejection groove that slides with the gradient drive rod 8. The end of the cleaning rod 7 slides with the side of the gradient drive rod 8. In practice, the diameter of the cleaning rod 7 is relatively small, and a special inclined slider is required to slide with the gradient drive rod 8. This slider is not shown in the figure. A boss is circumferentially formed on the outer periphery of the cleaning rod 7. A retraction groove that slides with the boss is formed inside the cylindrical spray head 5. The retraction spring 9 is located in the retraction groove, and its two ends abut against the inner walls of the boss and the end of the retraction groove, respectively. In actual operation, when cleaning the spray hole is required, the cylindrical spray head 5 is driven to retract into the mounting hole. When the cylindrical spray head 5 retracts into the mounting hole, since the position of the shoulder drive rod 8 remains unchanged, the other end of the cleaning rod 7 slides along the side of the gradient drive rod 8 under the rebound action of the retraction spring 9. As the width of the gradient drive rod 8 gradually increases, the cleaning rod 7 is driven to move laterally and insert into the spray hole, thus completing the cleaning of the spray hole. When spraying is required after cleaning, the cleaning rod 7 slides along the side of the gradient drive rod 8 under the rebound action of the retraction spring 9, and the spray hole is opened.
[0020] like Figure 2 and Figure 4 As shown, the drive mechanism includes an electric push rod 10 and a mounting frame 11; there are multiple cylindrical spray heads 5, each connected to a mounting frame 11. The cylindrical spray heads 5 are rotatably mounted on the mounting frame 11, and the mounting frame 11 is fixedly mounted on the output shaft of the electric push rod 10. The electric push rod 10 is mounted on the mounting plate 2. In actual use, multiple electric push rods 10 and multiple mounting frames 11 can be used, so that the cylindrical spray heads 5 are staggered and arranged in different areas. When performing hole cleaning operations, the spraying operation can still be ensured. The electric push rod 10 drives the mounting frame 11 to move up and down, which in turn drives the multiple cylindrical spray heads 5 to move up and down synchronously, realizing the hole cleaning operation of a large number of cylindrical spray heads 5. The structure is simple and the operation is convenient.
[0021] like Figure 4 , Figure 5 and Figure 6 As shown, a guiding mechanism is provided on the working plate 3; when the cylindrical spray head 5 slides in the mounting hole, the guiding mechanism can guide the cylindrical spray head 5 to rotate. In actual use, when cleaning the cylindrical spray head 5, the cylindrical spray head 5 will also rotate while retracting, which can wash away the dirt on the bottom surface of the working plate 3.
[0022] like Figure 4 , Figure 5 and Figure 6As shown, the guiding mechanism includes a sliding shaft 12; the sliding shaft 12 is fixedly installed on the inner wall of the mounting hole, and the outer periphery of the cylindrical spray head 5 is provided with a spiral groove 13 that slides with the sliding shaft 12. In actual use, when the cylindrical spray head 5 rises and retracts, since the position of the sliding shaft 12 in the mounting hole remains unchanged, the cylindrical spray head 5 moves up or down, and the sliding shaft 12 slides in the spiral groove 13, causing the cylindrical spray head 5 to rotate, which can wash away the dirt on the bottom surface of the working plate 3 and play a certain cleaning role.
[0023] like Figure 2 , Figure 3 and Figure 4 As shown, multiple through pipes 17 are installed through the mounting plate 2. The end of the through pipe 17 away from the mounting plate 2 passes through the working plate 3. The vacuum forming exhaust gas enters the upper space through the through pipe 17. In addition, the number of spray holes on the outer periphery of the cylindrical spray head 5 is the same as the number of adjacent through pipes 17. For example, the number of adjacent through pipes 17 around the cylindrical spray head 5 is 5, and the number of spray holes is also 5. The 5 spray holes are respectively aligned with the position directly below the 5 through pipes 17, which facilitates contact and mixing with the vacuum forming exhaust gas and improves the treatment effect.
[0024] like Figure 1 and Figure 2 As shown, the exhaust gas treatment tower 1 is connected to an air inlet pipe 14. The vacuum forming exhaust gas enters the exhaust gas treatment tower 1 through the air inlet pipe 14, moves upward, and then undergoes spray treatment. The top of the exhaust gas treatment tower 1 is connected to an exhaust pipe 15. The exhaust gas after spray treatment is discharged through the exhaust pipe 15 for subsequent treatment processes. The exhaust gas treatment tower 1 is also equipped with an inlet pipe 16 connected to the water storage chamber 4. The sprayed alkaline solution enters the water storage chamber 4 through the inlet pipe 16.
[0025] The steps for treating the exhaust gas from thermoforming are as follows: S1. Pre-treatment and collection of exhaust gas: Exhaust gas is first collected by a local gas collection hood (close to the heating and forming area) at the vacuum forming machine station. When the exhaust gas is transported through the guide duct, large particles of dust and plasticizer oil mist are intercepted by a simple filter screen inside the duct to prevent large impurities from directly entering the spray system and scratching or clogging the spray head. The duct design should reduce bends to ensure smooth airflow and avoid local eddies that cause impurities to accumulate. S2. Precise preparation of spray alkaline solution: Select alkaline solution according to the acidic components of the blister packaging exhaust gas: Use sodium hydroxide solution for blister packaging exhaust gas containing PVC (containing HCl), with the concentration controlled at 5%-8%; Use sodium carbonate solution for chlorine-free blister packaging exhaust gas, with the concentration at 3%-5%. The alkaline solution must be stirred evenly during preparation to avoid undissolved solid particles from entering the spray pipeline. After preparation, filter the solution through a filter screen and then inject it into the alkaline solution storage tank. S3. Reverse spraying neutralization reaction: The exhaust gas enters the lower part of the exhaust gas treatment tower 1 through the inlet pipe 14 and flows upward along the tower body; the alkaline solution is transported to the water storage chamber 4 at the top of the tower body by the pressurized pump, and sprayed downward in a mist form through the cylindrical spray head 5 to form gas-liquid reverse contact. During the spraying process, the spraying pressure is controlled at 0.1-0.3MPa to ensure that the droplet particle size is uniform (50-100m) and increase the contact area with the exhaust gas. S4. Gas-liquid separation and exhaust gas discharge: After neutralization, the exhaust gas, carrying a small amount of alkaline droplets, enters the gas-liquid separation zone at the top of the alkaline scrubbing tower. The droplets are intercepted by baffles or demisters to prevent alkaline liquid from being carried to subsequent treatment units. The separated exhaust gas is discharged through the top outlet of the tower and enters end-of-pipe treatment equipment such as photo-oxidation and activated carbon. The intercepted alkaline droplets are returned to the collection tank at the bottom of the tower for recycling. The above is existing technology and is not shown in the figure.
[0026] In S3, the vacuum forming exhaust gas is first mixed with the alkaline solution sprayed from the spray holes on the outer periphery of the cylindrical spray head 5, and then passes through the through pipe 17.
[0027] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A device for treating vacuum forming exhaust gas, characterized in that, The system includes an exhaust gas treatment tower (1), which is equipped with an installation plate (2) and a working plate (3). A water storage cavity (4) is formed between the installation plate (2) and the working plate (3). An installation hole is provided through the working plate (3). A cylindrical spray head (5) is slidably installed in the installation hole. An annular groove (6) communicating with the water storage cavity (4) is provided on the cylindrical spray head (5). A spray hole communicating with the annular groove (6) is provided on the outer periphery of the cylindrical spray head (5). The cylindrical spray head (5) is equipped with a cleaning mechanism, which is used to clean the dirt inside the spray hole; A drive mechanism is installed on the mounting plate (2), which is used to drive the cylindrical spray head (5) to extend and retract within the mounting hole.
2. The vacuum forming exhaust gas treatment device according to claim 1, characterized in that, The hole cleaning mechanism includes a hole cleaning rod (7) and an ejection assembly; the cylindrical spray head (5) has a receiving hole that slides with the hole cleaning rod (7), and one end of the cylindrical spray head (5) can be inserted into the spray hole and block the spray hole; The ejection assembly is used to drive the end of the cleaning rod (7) into the injection hole.
3. The vacuum forming exhaust gas treatment device according to claim 2, characterized in that, The ejection assembly includes a gradient drive rod (8) and a retraction spring (9); the gradient drive rod (8) is fixedly installed on the mounting plate (2), the cylindrical spray head (5) has an ejection groove that slides with the gradient drive rod (8), and the end of the cleaning rod (7) slides with the side of the gradient drive rod (8). The cleaning rod (7) has a boss on its outer circumference, and the cylindrical spray head (5) has a recessed groove that slides with the boss. The recessed spring (9) is located in the recessed groove, and the two ends of the recessed spring (9) abut against the inner wall of the end of the boss and the recessed groove, respectively.
4. The vacuum forming exhaust gas treatment device according to claim 3, characterized in that, The driving mechanism includes an electric push rod (10) and a mounting bracket (11); there are multiple cylindrical spray heads (5), and each of the multiple cylindrical spray heads (5) is connected to a mounting bracket (11). The mounting bracket (11) is fixedly installed on the output shaft of the electric push rod (10), and the electric push rod (10) is installed on the mounting plate (2).
5. The thermoforming waste gas treatment device according to claim 1, characterized in that, The working plate (3) is provided with a guiding mechanism; when the cylindrical spray head (5) slides in the mounting hole, the guiding mechanism can guide the cylindrical spray head (5) to rotate.
6. The vacuum forming exhaust gas treatment device according to claim 5, characterized in that, The guiding mechanism includes a sliding shaft (12); the sliding shaft (12) is fixedly installed on the inner wall of the mounting hole, and the outer periphery of the cylindrical spray head (5) is provided with a spiral groove (13) that slides with the sliding shaft (12).
7. The device for treating vacuum forming exhaust gas according to claim 1, characterized in that, Multiple through pipes (17) are installed through the mounting plate (2), and the end of the through pipe (17) away from the mounting plate (2) passes through the working plate (3).
8. The device for treating vacuum forming exhaust gas according to claim 1, characterized in that, The exhaust gas treatment tower (1) is connected to an air inlet pipe (14), the top of the exhaust gas treatment tower (1) is connected to an exhaust pipe (15), and the exhaust gas treatment tower (1) is also equipped with a liquid inlet pipe (16) connected to the water storage chamber (4).
9. A method for treating vacuum forming exhaust gas, using the vacuum forming exhaust gas treatment device according to any one of claims 1-8, characterized in that, The steps are as follows: S1. Pre-treatment and collection of exhaust gas; S2, Precise preparation of spray alkaline solution; S3, reverse spray neutralization reaction.
10. A method for treating vacuum forming exhaust gas according to claim 9, characterized in that, In S3, the vacuum forming exhaust gas is first mixed with the alkaline solution sprayed from the spray holes on the outer periphery of the cylindrical spray head (5), and then passes through the through pipe (17).