VOCs waste gas treatment device and use method thereof

Abstract

The invention discloses a VOCs waste gas treatment device and a use method thereof, and relates to the technical field of waste gas treatment.The VOCs waste gas treatment device comprises a spraying and cleaning unit, a waste gas treatment unit, a waste gas treatment unit, a waste gas treatment unit and a waste gas treatment unit, the spraying and cleaning unit is arranged in a spraying barrel, and a gas inlet pipe is arranged at the bottom of the spraying barrel; the adsorption and release unit is communicated with the spraying barrel through a discharge pipe, the adsorption and release unit comprises adsorption box shells, and an activated carbon block and an electric valve are arranged in each adsorption box shell; the catalytic oxidation unit comprises a heating chamber shell, a fan and a catalysis box, the fan and the catalysis box are arranged above and inside the heating chamber shell respectively, filter screens are arranged on the upper side and the lower side of the catalysis box, a metal catalyst is arranged in the catalysis box, and the fan is connected with the adsorption and release unit through a waste gas flow guide pipe; the bottom of the heating chamber shell is connected with the adsorption release unit through a hot air return pipe; the exhaust funnel is connected with the air outlet end of the adsorption and release unit, and the bottom of the heating chamber shell is also connected with the exhaust funnel; the device can improve the VOCs treatment efficiency and reduce the use frequency of the activated carbon blocks.

Description

Technical Field

[0001] This invention belongs to the field of waste gas treatment technology, and more specifically, relates to a VOCs waste gas treatment device and its usage method. Background Technology

[0002] Volatile organic compounds (VOCs) are a class of organic compounds that are easily volatilized at room temperature. These compounds have boiling points between 50 and 260 degrees Celsius at room temperature and pose potential hazards to the environment and human health.

[0003] Existing VOCs waste gas treatment devices reduce VOCs concentration and eliminate the harmfulness of VOCs-containing waste gas by cleaning esters with cleaning fluid, adsorbing VOCs with activated carbon blocks, regenerating activated carbon blocks, and oxidizing VOCs. However, the regeneration of activated carbon blocks requires a high-temperature environment. Therefore, in existing technologies, activated carbon block regeneration and VOCs oxidation occur simultaneously to share the same heat. Prolonged exposure to high temperatures leads to decreased adsorption capacity of activated carbon blocks. During VOCs oxidation, the metal catalyst cannot fully oxidize VOCs, limiting the regeneration rate of activated carbon blocks to the oxidation rate of VOCs. Furthermore, high-frequency adsorption and regeneration of activated carbon blocks significantly reduces their lifespan. Long-term cleaning of VOCs waste gas with cleaning fluid also causes the cleaning fluid temperature to rise, leading to the volatilization of some dissolved VOCs, such as acetone and dimethyl ether, further increasing the burden on activated carbon blocks for VOCs adsorption. Therefore, there is an urgent need for a VOCs waste gas treatment device that can improve VOCs treatment efficiency and reduce the frequency of activated carbon block usage. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a VOCs waste gas treatment device and its usage method. This waste gas treatment device can overcome the limitations imposed by the slow oxidation rate of VOCs on the regeneration rate of activated carbon blocks, and the disadvantage that the volatilization of VOCs in the cleaning solution will increase the burden on the activated carbon blocks. This device can improve the VOCs treatment efficiency and reduce the frequency of use of activated carbon blocks.

[0005] To achieve the above objectives, the present invention provides a VOCs waste gas treatment device, comprising:

[0006] A spray cleaning unit is installed inside a spray cylinder. The bottom of the spray cylinder contains cleaning fluid, and an air inlet pipe is installed through the bottom of the spray cylinder.

[0007] The adsorption and release unit is connected to the top of the spray cylinder through the first exhaust pipe. The adsorption and release unit includes multiple adsorption box shells arranged in parallel. Each adsorption box shell is equipped with an activated carbon block and an electric valve.

[0008] A catalytic oxidation unit includes a heating chamber shell, a fan, and a catalytic box. The fan and the catalytic box are respectively located above and inside the heating chamber shell. Filter screens are provided at the top and bottom of the catalytic box. A metal catalyst is provided inside the catalytic box. The air inlet of the fan is connected to the air outlet of the adsorption and release unit through an exhaust gas guide pipe. The bottom of the heating chamber shell is connected to the air inlet of the adsorption and release unit through a hot air return pipe.

[0009] The exhaust stack is connected to the outlet of the adsorption and release unit via a second exhaust pipe, and the bottom of the heating chamber shell is also connected to the exhaust stack via a third exhaust pipe.

[0010] Preferably, the spray cleaning unit includes:

[0011] A one-way valve is provided at the end of the air inlet pipe located inside the spray cylinder;

[0012] A sealing shell is disposed at the bottom of the spray cylinder. The air inlet pipe is fixedly connected to the sealing shell. An impeller shaft is rotatably disposed on the sealing shell. The impeller shaft is disposed along the axis of the spray cylinder. Multiple blade combinations are disposed along the length direction of the impeller shaft. Each blade combination includes multiple blades. The blades in each blade combination are disposed circumferentially along the impeller shaft.

[0013] Preferably, the spray cleaning unit further includes:

[0014] A liquid pump is located outside the spray cylinder. The inlet of the liquid pump is connected to the inside of the spray cylinder. The height of the inlet of the liquid pump is set below the liquid surface of the cleaning liquid.

[0015] A cross tube is located at the top inside the spray cylinder. Multiple atomizing nozzles are provided on the lower surface of the cross tube. The cross tube is connected to the outlet of the liquid pump.

[0016] Preferably, a sealed door is provided on one side of the adsorption box shell, and an upper ventilator and a lower ventilator are respectively provided above and below the activated carbon block inside the adsorption box shell.

[0017] Preferably, the adsorption-release unit further includes:

[0018] Two support frames are respectively arranged on both sides of all the adsorption box shells, and the first exhaust gas pipe is arranged through the support frames;

[0019] Each of the adsorption box housings is provided with an electric valve at the top and bottom. The electric valve at the top and the exhaust gas guide pipe are connected to the space above the upper vent plate of the adsorption box housing. The electric valve at the bottom and the hot air return pipe are connected to the space below the lower vent plate of the adsorption box housing.

[0020] Preferably, the catalytic oxidation unit comprises:

[0021] An upper partition and a lower partition are respectively disposed inside the outer shell of the heating chamber, and a plurality of electric heating columns are disposed between the upper partition and the lower partition;

[0022] A conical cylinder is disposed at the bottom of the lower partition plate, and the lower part of the conical cylinder is in communication with the catalyst box;

[0023] A conical nozzle is disposed on one side of the upper partition and the lower partition that are close to each other, and multiple conical nozzles are disposed on the upper partition and the lower partition respectively.

[0024] Preferably, the catalytic oxidation unit further includes a trapezoidal wind baffle ring, the outer periphery of which is connected to the inner wall of the heating chamber shell, and two trapezoidal wind baffle rings are arranged between the upper partition and the lower partition, with the inclined surfaces of the two trapezoidal wind baffle rings respectively arranged on opposite sides.

[0025] Preferably, the exhaust stack is provided with a liquid support frame and a liquid separator frame, which are located above the connection between the second exhaust pipe and the third exhaust pipe. The liquid support frame includes an annular plate portion and a tubular portion. The bottom outer peripheral surface of the tubular portion is connected to the inner peripheral surface of the annular plate, and the outer peripheral surface of the annular plate portion is connected to the inner wall of the exhaust stack. The liquid separator frame includes a round cover portion and multiple connecting portions. The round cover portion is fastened to the top of the liquid support frame, and the outer peripheral sidewall of the round cover portion is located on the outer periphery of the tubular portion. The outer periphery of the round cover portion is connected to the inner wall of the exhaust stack through the multiple connecting portions. There is a gap between the bottom of the outer peripheral sidewall of the round cover portion and the annular plate portion. An alkaline absorbent liquid is disposed above the annular plate portion, and the liquid level of the alkaline absorbent liquid is higher than the bottom of the outer peripheral sidewall of the round cover portion.

[0026] The present invention also provides a method of using a VOCs waste gas treatment device, wherein the method of using the above-mentioned VOCs waste gas treatment device includes:

[0027] Place the activated carbon block into the adsorption box shell, open the electric valve, and connect the external VOCs waste gas collection device to the inlet pipe.

[0028] When the liquid pump on the spray cylinder is started, the exhaust gas inside the spray cylinder will move into the first exhaust gas discharge pipe through pressure difference diffusion.

[0029] The electric valve should be closed only when the activated carbon block needs to be regenerated.

[0030] Preferably, the regeneration treatment method for activated carbon blocks is as follows:

[0031] The fan and the electric heating column in the heating chamber shell are started. The exhaust gas enters the heating chamber shell from the exhaust gas guide pipe. After the exhaust gas is decomposed by the catalytic oxidation unit, part of the exhaust gas is sent back to the adsorption box shell through the hot air return pipe to regenerate the activated carbon blocks.

[0032] This invention provides a VOCs waste gas treatment device and its usage method, the advantages of which are:

[0033] 1. This waste gas treatment device uses waste gas to blow onto a powdered metal catalyst inside a catalytic box. The powdered metal catalyst is blown up by the waste gas and fills the catalytic box. The flying powdered metal catalyst uses the heat of the waste gas to oxidize VOCs in the waste gas into carbon dioxide and water. Since the metal catalyst is in a suspended state in the catalytic box and there is always high-temperature waste gas flowing on the surface of the metal catalyst, the water produced by VOCs decomposition will be quickly evaporated, thus preventing the powdered metal catalyst from becoming damp and sticking together. Under the blowing of the waste gas, the powdered metal catalyst catalyzes the waste gas in a suspended state in the catalytic box. The large contact surface between the catalyst and the waste gas greatly accelerates the catalytic treatment process of VOCs and improves the efficiency of VOCs decomposition.

[0034] 2. The spray cleaning unit of this waste gas treatment device is equipped with blades. When the blades rotate, they generate a downward straight airflow. When the waste gas airflow comes into contact with the straight airflow located at the center of the spray cylinder, the waste gas airflow will be driven by the straight airflow and flow vertically downward at the center of the spray cylinder. Then, it will approach the inner wall of the spray cylinder above the cleaning liquid and flow vertically upward along the inner wall of the spray cylinder and return to the initial position, generating a vertical annular airflow. The waste gas airflow will also generate a horizontal rotating airflow along the rotation of the blades. The rotating airflow makes the waste gas stay in the spray cylinder for a longer time, so that the atomized cleaning liquid can fully absorb the water-soluble VOCs and particulate matter in the waste gas, thereby improving the cleaning efficiency of the cleaning liquid in cleaning the waste gas.

[0035] 3. When the waste gas treatment device cleans the waste gas in the spray cylinder with cleaning liquid, the cleaning liquid will gradually absorb the heat of the waste gas and thus the temperature will rise. Since the surface area of ​​the cleaning liquid increases significantly after atomization, and the cleaning liquid moves faster under the influence of airflow and is more volatile, the cleaning liquid will reduce the internal temperature of the spray cylinder in the form of evaporation, thereby reducing the volatilization of water-soluble VOCs. Furthermore, the atomization method prevents the re-evaporation of water-soluble VOCs from mixing into the already cleaned waste gas, thus improving the efficiency of the cleaning liquid in cleaning the waste gas.

[0036] 4. The waste gas treatment device has an accelerating cone installed between the spray cylinder and the first waste gas discharge pipe. In this way, the waste gas enters from the large diameter of the accelerating cone and flows out from the small diameter of the accelerating cone. The cross-sectional area of ​​the waste gas flow is restricted by the accelerating cone, thus reducing the size of the flow area and accelerating the flow speed of the waste gas. The waste gas located at the edge of the flow is confined by the outer wall of the flow-limiting cone, the inner wall of the first waste gas discharge pipe, and the outer wall of the accelerating cone during the flow process, forming a circulation. The waste gas located at the center of the flow is not obstructed by the flow-limiting cone, so the flow velocity is higher and the pressure is lower. This attracts the surrounding waste gas to move towards the center of the flow, thereby reducing the adhesion of room temperature solid VOCs in the waste gas to the pipe wall and preventing the first waste gas discharge pipe from being blocked by room temperature solid VOCs after long-term use, which would reduce the VOCs treatment efficiency.

[0037] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0038] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0039] Figure 1 A schematic diagram of a VOCs waste gas treatment device according to an embodiment of the present invention is shown.

[0040] Figure 2 It shows Figure 1 Rear view diagram.

[0041] Figure 3 A first-view half-section schematic diagram of the heating chamber shell according to an embodiment of the present invention is shown.

[0042] Figure 4 A second-view half-section schematic diagram of the heating chamber shell according to an embodiment of the present invention is shown.

[0043] Figure 5 A half-sectional schematic diagram of a catalyst box according to an embodiment of the present invention is shown.

[0044] Figure 6 A partial cross-sectional view of a spray cylinder according to an embodiment of the present invention is shown.

[0045] Figure 7 A schematic diagram of the impeller shaft according to an embodiment of the present invention is shown.

[0046] Figure 8 A schematic diagram of the connection of an adsorption-release unit according to an embodiment of the present invention is shown.

[0047] Figure 9 A schematic diagram showing the arrangement of activated carbon blocks in the adsorption box housing according to an embodiment of the present invention is shown.

[0048] Figure 10 A half-sectional schematic diagram of the adsorption box housing according to an embodiment of the present invention is shown.

[0049] Figure 11 A partial cross-sectional view of a liquid tray and a liquid separator according to an embodiment of the present invention is shown.

[0050] Explanation of reference numerals in the attached figures:

[0051] 1. Spray cylinder; 101. Spray cleaning unit; 102. Air inlet pipe; 1021. One-way valve; 103. Sealing shell; 104. Impeller shaft; 105. Blade; 106. Liquid pump; 107. Cross tube; 108. Atomizing nozzle; 2. First exhaust gas discharge pipe; 201. Accelerating cone; 202. Flow limiting cone; 3. Adsorption and release unit; 301. Support frame; 302. Adsorption box shell; 3021. Electric valve; 303. Sealing door; 304. Upper vent plate; 30 5. Activated carbon block; 306. Lower permeable plate; 4. Second exhaust pipe; 5. Exhaust gas guide pipe; 6. Hot air return pipe; 7. Catalytic oxidation unit; 701. Heating chamber shell; 702. Fan; 703. Upper partition; 704. Electric heating column; 705. Conical nozzle; 706. Trapezoidal wind baffle ring; 707. Conical cylinder; 708. Catalytic box; 709. Filter screen; 710. Lower partition; 8. Third exhaust pipe; 9. Exhaust stack; 901. Liquid support rack; 902. Liquid separator rack. Detailed Implementation

[0052] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0053] This invention provides a VOCs waste gas treatment device, such as... Figures 1-5As shown, the system includes a spray cylinder 1, inside which a spray cleaning unit 101 is installed. The spray cleaning unit 101 is used to absorb particulate matter in the exhaust gas. The bottom of the spray cylinder 1 contains cleaning liquid. It also includes a first exhaust gas discharge pipe 2, which is connected to the top of the spray cylinder 1. An adsorption and release unit 3 is installed on the first exhaust gas discharge pipe 2. An exhaust gas guide pipe 5 and a hot air return pipe 6 are connected to the adsorption and release unit 3. A catalytic oxidation unit 7 is installed on the exhaust gas guide pipe 5 and the hot air return pipe 6. The catalytic oxidation unit 7 includes a heating chamber shell 701, and one end of the hot air return pipe 6 is connected to the heating chamber shell 701. A fan 702 is fixedly installed on the top of the outer wall of the heating chamber shell 701. The outlet of the fan 702 is connected to the heating chamber shell 701, and the inlet of the fan 702 is fixedly connected to the exhaust gas guide pipe 5. An upper partition 703 and a lower partition 710 are fixedly connected vertically inside the heating chamber shell 701. A conical cylinder 707 is fixedly connected to the bottom of the lower partition 710. A catalyst box 708 is fixedly connected to the bottom of the conical cylinder 707. A filter screen 709 is fixedly connected to both the top and bottom of the catalyst box 708. A powdered metal catalyst is placed inside the catalyst box 708. The pore size of the filter screen 709 is smaller than the diameter of the metal catalyst to prevent the metal catalyst from being blown out by the exhaust gas.

[0054] like Figures 3-5 As shown, the catalytic oxidation unit 7 also includes an electric heating column 704. Several electric heating columns 704 are connected between the two partitions 703, and several conical nozzles 705 are installed in a through rectangular distribution on both partitions 703. The conical ends of the top conical nozzles 705 and the bottom conical nozzles 705 are both directed vertically toward the center of the electric heating column 704.

[0055] like Figures 3-5 As shown, the catalytic oxidation unit 7 also includes a trapezoidal baffle ring 706. The trapezoidal baffle ring 706 is fixed inside the heating chamber shell 701. The trapezoidal baffle ring 706 is located between the upper and lower partitions. The trapezoidal baffle ring 706 is used to guide the exhaust gas sprayed from the conical nozzle 705, so that the exhaust gas is better heated.

[0056] like Figure 1 and Figures 6-7 As shown, the spray cleaning unit 101 includes an air inlet pipe 102. The air inlet pipe 102 is fixedly connected through the spray cylinder 1. The air inlet pipe 102 is submerged in cleaning liquid. A one-way valve 1021 is installed at one end of the air inlet pipe 102. A sealing shell 103 is fixedly connected to the air inlet pipe 102. The bottom of the sealing shell 103 is fixedly connected to the spray cylinder 1. An impeller shaft 104 is rotatably connected inside the sealing shell 103. Several blades 105 are circumferentially distributed and vertically fixedly connected to the impeller shaft 104. When the blades 105 rotate, they can generate a downward spiral airflow.

[0057] like Figure 6As shown, the spray cleaning unit 101 also includes a liquid pump 106. The liquid pump 106 is installed on the outer wall of the spray cylinder 1. The liquid pump 106 is fixedly connected to a cross tube 107 through a liquid delivery pipe. The cross tube 107 is fixedly connected to the spray cylinder 1 through a through-hole connection. Several atomizing nozzles 108 are installed at the bottom of the cross tube 107. The atomizing nozzles 108 can spray out atomized particles with a diameter of 20 micrometers. The atomized particles with a diameter of 20 micrometers can be suspended in the spray cylinder 1 for a relatively long time. The spray cleaning unit 101 also includes an accelerating cone 201 and a flow-limiting cone 202. The accelerating cone 201 and the flow-limiting cone 202 are fixedly connected in the first exhaust gas discharge pipe 2. The accelerating cone 201 and the flow-limiting cone 202 are close to each other and their conical ends are close to each other.

[0058] like Figures 1-2 and Figures 8-9 As shown, the adsorption and release unit 3 includes an adsorption box housing 302. Several adsorption box housings 302 are linearly distributed and fixedly connected to the first exhaust gas pipe 2. A sealing door 303 is installed on one side of the adsorption box housing 302. An upper ventilator plate 304 and a lower ventilator plate 306 are distributed and fixedly connected inside the adsorption box housing 302. Activated carbon 305 is placed above the lower ventilator plate 306, and the activated carbon block 305 completely covers the ventilator holes of the lower ventilator plate 306.

[0059] like Figures 1-2 and Figure 8 As shown, the adsorption and release unit 3 also includes a support frame 301. The support frame 301 is fixedly connected to one side of each adsorption box shell 302 that is far apart from each other. The top of several adsorption box shells 302 are connected to a second exhaust pipe 4, which is used to discharge exhaust gas from the first exhaust pipe 2.

[0060] like Figures 9-10 As shown, the adsorption and release unit 3 also includes an electric valve 3021. The top and bottom of several adsorption box shells 302 are each equipped with an electric valve 3021. The top of several adsorption box shells 302 are connected to the exhaust gas guide pipe 5, and the bottom of several adsorption box shells 302 are connected to the hot air return pipe 6. The hot air return pipe 6 has the function of restricting the unidirectional flow of internal airflow, so that the airflow can only flow from the heating chamber shell 701 to the adsorption box shell 302.

[0061] like Figure 1 and Figure 11As shown, it also includes a third exhaust pipe 8. The bottom of the heating chamber shell 701 is connected to the third exhaust pipe 8. The third exhaust pipe 8 and the second exhaust pipe 4 are connected to an exhaust stack 9 at one end. The third exhaust pipe 8 has the function of restricting the internal airflow to flow in one direction, so that the airflow can only flow from the catalytic oxidation unit 7 to the exhaust stack 9. A liquid support rack 901 and a liquid separator rack 902 are fixed inside the exhaust stack 9. The liquid support rack 901 and the liquid separator rack 902 are located above the second exhaust pipe 4. An alkaline absorbent is placed above the liquid support rack 901.

[0062] Initially, all electric valves 3021 are open. The operator connects the external VOCs waste gas collection device to the inlet pipe 102 and opens the sealing door 303. Activated carbon blocks 305 are placed on the lower permeable plate 306, covering the permeable holes to prevent waste gas leakage. This ensures all waste gas is adsorbed and filtered by the activated carbon blocks 305. The operator then closes the sealing door 303 and starts the liquid pump 106. The VOCs waste gas collection device introduces VOCs-containing, heat-laden waste gas into the inlet pipe 102, allowing it to pass through the one-way valve 1021 into the spray cylinder 1. Inside the spray cylinder 1, the waste gas comes into contact with the cleaning liquid, thus removing VOCs. In addition to removing water-soluble VOCs from the exhaust gas, the exhaust gas entering the spray cylinder 1 simultaneously blows the impeller shaft 104, causing it to rotate. This rotation of the impeller shaft 104 drives the blades 105 to rotate synchronously, generating a downward vertical airflow. The velocity of the center portion of the blades 105 is lower than that of their edges, thus creating a shearing force on the air and forming a rotating airflow. The vertical and rotating airflows overlap to form a spiral airflow. The exhaust gas airflow comes into contact with this spiral airflow at the center of the spray cylinder 1. Because the exhaust gas airflow flows upwards through free diffusion and does not possess sufficient wind force, it is carried by the spiral airflow and flows vertically downwards at the center of the spray cylinder 1. After reaching the lower part of the interior of the spray cylinder 1... The exhaust gas is obstructed by the surface of the cleaning fluid and thus approaches the inner wall of the spray cylinder 1. The inner wall of the spray cylinder 1 provides the most significant resistance to the diffusion of the exhaust gas flow. As the exhaust gas flows downward, the pressure at the bottom of the spray cylinder 1 gradually increases. Therefore, the exhaust gas flow will flow vertically upward along the inner wall of the spray cylinder 1 and reach the top of the spray cylinder 1. After the exhaust gas flow reaches the top of the spray cylinder 1, due to the higher velocity and lower pressure of the spiral airflow generated by the blades 105, the exhaust gas flow at the top of the spray cylinder 1 is attracted by the spiral airflow at the center of the spray cylinder 1 and returns to its initial position before flowing vertically downward, thus generating a vertical annular airflow. The rotating airflow increases the flow path of the exhaust gas flow, allowing the exhaust gas to remain in the spray cylinder 1 for a longer time. The pump 106 draws cleaning fluid into the spray cylinder 1 and delivers it to the cross tube 107 via the infusion pipe. The cleaning fluid is then atomized and sprayed out through the atomizing nozzle 108. After atomization, the surface area of ​​the cleaning fluid increases significantly. Influenced by the annular airflow, the atomized cleaning fluid fills the entire spray cylinder 1, allowing it to fully absorb water-soluble VOCs and particulate matter from the exhaust gas. This improves the absorption effect of the cleaning fluid on the exhaust gas and increases its cleaning efficiency. As the cleaning fluid cleans the exhaust gas, it gradually absorbs heat from the exhaust gas, causing its temperature to rise. Because the surface area of ​​the cleaning fluid increases significantly after atomization, and because the cleaning fluid moves quickly under the influence of the airflow, it is more prone to evaporation. Therefore, the cleaning fluid will reduce the internal temperature of the spray cylinder 1 through evaporation.This reduces the volatilization of water-soluble VOCs and, through atomization, prevents water-soluble VOCs that re-evaporate within spray cylinder 1 from mixing into the already cleaned exhaust gas, thereby improving the efficiency of the cleaning solution in cleaning exhaust gas.

[0063] After being cleaned, the exhaust gas inside the spray cylinder 1 moves towards the first exhaust gas discharge pipe 2 through pressure difference diffusion as the pressure inside the spray cylinder 1 increases. When the exhaust gas reaches the acceleration cone 201, it enters from the larger diameter and exits from the smaller diameter. The cross-sectional area of ​​the exhaust gas flow is restricted by the acceleration cone 201, thus decreasing. Based on Bernoulli's principle, the reduced cross-sectional area of ​​the exhaust gas flow increases its velocity. When the exhaust gas reaches the smaller diameter of the acceleration cone 201, it is no longer restricted and diffuses outwards. The airflow generated by the diffusion of the exhaust gas under inertia is cone-shaped. The exhaust gas at the center of this airflow maintains its original flow direction and enters the flow-limiting cone 202 vertically upwards. It diffuses under the restriction of the inner wall of the flow-limiting cone 202, and its velocity gradually decreases. The exhaust gas at the edge of this airflow... During the diffusion process, the flow is slowed down and limited by the outer wall of the flow-limiting cone 202. The gas flows along the outer wall of the flow-limiting cone 202. Under the limiting effect of the inner wall of the first exhaust gas discharge pipe 2, the exhaust gas at the edge of the gas flow flows back to the small diameter of the acceleration cone 201 along the inner wall of the first exhaust gas discharge pipe 2. Under the obstruction of the outer wall of the acceleration cone 201, it flows back to its original position along the outer wall of the acceleration cone 201, thus forming a circulation. The exhaust gas at the edge of the gas flow circulates in the circulation. Since the exhaust gas located at the center of the gas flow is not obstructed by the flow-limiting cone 202, the flow velocity is high and the pressure is low. This attracts the surrounding exhaust gas to move towards the center of the gas flow, thereby reducing the adhesion of room temperature solid VOCs such as dimethyl disulfide to the inner wall of the first exhaust gas discharge pipe 2. This avoids the situation where the first exhaust gas discharge pipe 2 is blocked by room temperature solid VOCs after long-term use, which would lead to a decrease in the VOCs treatment efficiency.

[0064] When the exhaust gas enters the first exhaust gas discharge pipe 2, it flows along the pipe and passes through the electric valve 3021 at the bottom of the adsorption box housing 302. Since the hot air return pipe 6 restricts unidirectional airflow, the airflow can only flow from the heating chamber outer shell 701 to the adsorption box housing 302. Therefore, the exhaust gas diffuses upwards and contacts the activated carbon block 305. The porous structure of the activated carbon block 305 adsorbs odors and VOCs from the exhaust gas, allowing it to be discharged normally. After passing through and being adsorbed by the activated carbon 305, the exhaust gas is blocked by the fan 702 after entering the exhaust gas guide pipe 5, as the fan 702 is not yet running. This causes the exhaust gas to flow upwards through the electric valve 3021 located at the top of the adsorption box housing 302. The exhaust gas enters the exhaust stack 9 through the second exhaust pipe 4. The exhaust gas diffuses along the exhaust stack 9 and enters the liquid support 901, where it comes into contact with the alkaline absorbent liquid on the liquid support 901. As the amount of exhaust gas entering the exhaust stack 9 increases, the pressure inside the exhaust stack 9 rises due to the communicating vessel structure formed by the liquid support 901 and the liquid separator 902. This causes the alkaline absorbent liquid between the inner wall of the liquid separator 902 and the top of the liquid support 901 to move between the liquid separator 902 and the exhaust stack 9. The level of the alkaline absorbent liquid between the inner wall of the liquid separator 902 and the top of the liquid support 901 decreases until the exhaust gas can bypass the restriction between the liquid separator 902 and the alkaline absorbent liquid from the bottom of the liquid separator 902. The exhaust gas is then released outward in the form of bubbles in the alkaline absorbent liquid, thus discharging the exhaust gas to the outside world and finally exiting the device from the exhaust stack 9.

[0065] When activated carbon block 305 absorbs a large amount of VOCs, a VOCs film will cover the porous surface of activated carbon block 305, reducing its adsorption capacity. At this point, activated carbon block 305 needs to be regenerated to restore its adsorption capacity. The operator closes the electric valves 3021 above and below activated carbon block 305 to prevent exhaust gas from entering the corresponding adsorption chamber shell 302. The operator then starts the fan 702 and electric heating column 704, causing the fan 702 to draw exhaust gas into the adsorption chamber shell 302 through the exhaust gas guide pipe 5. Guided by the fan 702, the exhaust gas enters the top of the heating chamber shell 701 through the exhaust gas guide pipe 5. As the exhaust gas is continuously drawn into the heating chamber... As the exhaust gas inside the outer casing 701 and heating chamber continuously increases, it enters the space between two partitions through the top conical nozzle 705. Based on Bernoulli's principle, the conical structure of the nozzle 705 causes the flow cross-sectional area of ​​the exhaust gas to gradually decrease as it enters the space between the two partitions, thus gradually increasing the flow velocity of the exhaust gas. The gas then blows onto the trapezoidal baffle ring 706 and is guided by the baffle ring 706 towards the electric heating column 704, thereby allowing the electric heating column 704 to fully heat the exhaust gas. As the exhaust gas at the electric heating column 704 continues to increase, it enters the conical nozzle 705 through pressure difference diffusion and, based on Bernoulli's principle, is ejected along the inner wall of the nozzle 705, where the flowable cross-sectional area gradually increases. It is worth noting that because the exhaust gas exits from between the two partitions... A large cavity suddenly enters the conical nozzle 705, causing turbulence in the exhaust gas flowing at its conical nozzle 705 due to the rapid change in cross-sectional area. This turbulence slows the exhaust gas as it exits between the two baffles, ensuring it is fully heated at the electric heating column 704. The exhaust gas then enters the conical cylinder 707 through the bottom conical nozzle 705 and accelerates along its internal conical surface before passing through the filter screen 709 and entering the catalytic converter 708. Simultaneously, the exhaust gas blows onto the powdered metal catalyst within the catalytic converter 708, causing it to be lifted and fill the catalytic converter 708. The lifted powdered metal catalyst utilizes the heat of the exhaust gas to oxidize the VOCs in the exhaust gas. The VOCs are converted into carbon dioxide and water. Because the metal catalyst is in a suspended state in the catalytic box 708 and there is always high-temperature exhaust gas flowing over its surface, the water produced by VOCs decomposition is quickly evaporated, thus preventing the powdered metal catalyst from becoming damp and sticking together. Under the blowing of the exhaust gas, the powdered metal catalyst catalyzes the exhaust gas in a suspended state within the catalytic box 708. The large contact surface between the catalyst and the exhaust gas greatly accelerates the catalytic treatment process of VOCs and improves the efficiency of VOCs decomposition. Subsequently, the decomposed exhaust gas continues to flow downwards, passing through the filter screen 709 located at the bottom and reaching the bottom of the heating chamber shell 701. Part of the decomposed exhaust gas enters the exhaust stack 9 through the third exhaust gas discharge pipe 8 at the bottom of the heating chamber shell 701.The waste gas diffuses along the exhaust stack 9 into the liquid absorber 901, where it comes into contact with the alkaline absorbent liquid. It's worth noting that during VOCs decomposition, chlorides and sulfur oxides are produced due to their elemental composition. These chlorides and sulfur oxides are absorbed by the alkaline absorbent liquid upon contact, thus preventing environmental pollution. As the amount of waste gas entering the exhaust stack 9 increases, the pressure causes the alkaline absorbent liquid between the inner wall of the liquid absorber 902 and the top of the liquid absorber 901 to move between the liquid absorber 902 and the exhaust stack 9. The level of the alkaline absorbent liquid between the inner wall of the liquid absorber 902 and the top of the liquid absorber 901 decreases until the waste gas can bypass the liquid absorber 901 from the bottom. The restriction of the alkaline absorbent liquid causes the waste gas to be released outward in the form of bubbles, thus discharging the waste gas to the outside. Another portion of the decomposed waste gas enters the adsorption box shell 302 through the hot air return pipe 6 at the bottom of the heating chamber shell 701. The high temperature of the adsorbed VOCs by the activated carbon block 305 releases the VOCs, regenerating the activated carbon block 305. The released VOCs then enter the heating chamber shell 701 through the waste gas guide pipe 5, guided by the fan 702. This VOCs decomposition process is repeated until the adsorption capacity of the activated carbon block 305 is fully restored. Afterward, the operator shuts off the fan 702 and the electric heating column 704, and opens the closed electric valve 3021, allowing the activated carbon block 305 to continue treating waste gas.

[0066] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A VOCs waste gas treatment device, characterized in that, include: A spray cleaning unit (101) is installed inside a spray cylinder (1). The bottom of the spray cylinder (1) contains cleaning liquid, and an air inlet pipe (102) is installed through the bottom of the spray cylinder (1). The adsorption release unit (3) is connected to the top of the spray cylinder (1) through the first exhaust pipe (2). The adsorption release unit (3) includes multiple adsorption box shells (302) arranged in parallel. Each adsorption box shell (302) is provided with an activated carbon block (305) and an electric valve (3021). The catalytic oxidation unit (7) includes a heating chamber shell (701), a fan (702), and a catalyst box (708). The fan (702) and the catalyst box (708) are respectively located above and inside the heating chamber shell (701). The top and bottom of the catalyst box (708) are provided with filters (709). The inside of the catalyst box (708) is provided with a metal catalyst. The air inlet of the fan is connected to the air outlet of the adsorption and release unit (3) through a waste gas guide pipe (5). The bottom of the heating chamber shell (701) is connected to the air inlet of the adsorption and release unit (3) through a hot air return pipe (6). The exhaust stack (9) is connected to the outlet of the adsorption and release unit (3) through the second exhaust pipe (4), and the bottom of the heating chamber shell (701) is also connected to the exhaust stack through the third exhaust pipe (8).

2. The VOCs waste gas treatment device according to claim 1, characterized in that, The spray cleaning unit includes: A one-way valve (1021) is provided at the end of the air inlet pipe (102) located inside the spray cylinder (1); A sealing shell (103) is disposed at the bottom of the spray cylinder (1). The air inlet pipe (102) is fixedly connected to the sealing shell (103). An impeller shaft (104) is rotatably disposed on the sealing shell (103). The impeller shaft (104) is disposed along the axis of the spray cylinder (1). The impeller shaft (104) is provided with multiple blade combinations along its length direction. Each blade combination includes multiple blades (105). The blades (105) in each blade combination are disposed circumferentially along the impeller shaft (104).

3. The VOCs waste gas treatment device according to claim 2, characterized in that, The spray cleaning unit also includes: A liquid pump (106) is located outside the spray cylinder (1). The inlet of the liquid pump (106) is connected to the inside of the spray cylinder (1). The height of the inlet of the liquid pump (106) is set below the liquid surface of the cleaning liquid. A cross tube (107) is located at the top inside the spray cylinder (1). Multiple atomizing nozzles (108) are provided on the lower surface of the cross tube (107). The cross tube (107) is connected to the outlet of the liquid pump (106).

4. The VOCs waste gas treatment device according to claim 1, characterized in that, A sealing door (303) is provided on one side of the adsorption box housing (302), and an upper ventilator (304) and a lower ventilator (306) are respectively provided inside the adsorption box housing (302) above and below the activated carbon block (305).

5. The VOCs waste gas treatment device according to claim 4, characterized in that, The adsorption and release unit (3) further includes: Two support frames (301) are respectively disposed on both sides of all the adsorption box shells (302), and the first exhaust gas discharge pipe (2) is disposed through the support frame (301); Each of the adsorption box housings (302) is provided with an electric valve (3021) at its top and bottom. The electric valve (3021) at the top and the exhaust gas guide pipe (5) are connected to the space above the upper vent plate (304) of the adsorption box housing (302). The electric valve (3021) at the bottom and the hot air return pipe (6) are connected to the space below the lower vent plate (306) of the adsorption box housing (302).

6. The VOCs waste gas treatment device according to claim 1, characterized in that, The catalytic oxidation unit (7) includes: An upper partition (703) and a lower partition (710) are respectively disposed inside the outer shell (701) of the heating chamber, and a plurality of electric heating columns (704) are disposed between the upper partition (703) and the lower partition (710); A conical cylinder (707) is disposed at the bottom of the lower partition plate (710), and the lower part of the conical cylinder (707) is in communication with the catalyst box (708); A conical nozzle (705) is disposed on one side of the upper partition (703) and the lower partition (710) that are close to each other. Multiple conical nozzles (705) are disposed on the upper partition (703) and the lower partition (710).

7. The VOCs waste gas treatment device according to claim 6, characterized in that, The catalytic oxidation unit (7) also includes a trapezoidal wind deflector ring (706), the outer periphery of which is connected to the inner wall of the heating chamber shell (701). Two trapezoidal wind deflector rings (706) are provided between the upper partition (703) and the lower partition (710), and the inclined surfaces of the two trapezoidal wind deflector rings (706) are respectively provided on opposite sides.

8. The VOCs waste gas treatment device according to claim 1, characterized in that, The exhaust stack (9) is equipped with a liquid support frame (901) and a liquid separator frame (902). The liquid support frame (901) and the liquid separator frame (902) are located above the connection between the second exhaust pipe (4) and the third exhaust pipe (8). The liquid support frame (901) includes an annular plate portion and a tubular portion. The outer peripheral surface of the bottom of the tubular portion is connected to the inner peripheral surface of the annular plate, and the outer peripheral surface of the annular plate portion is connected to the inner wall of the exhaust stack (9). The liquid separator frame (902) is located above the connection between the second exhaust pipe (4) and the third exhaust pipe (8). The frame (902) includes a round cover and multiple connecting parts. The round cover is fastened above the liquid holder (901). The outer peripheral sidewall of the round cover is located on the outer periphery of the tubular part. The outer periphery of the round cover is connected to the inner wall of the exhaust pipe (9) through the multiple connecting parts. There is a gap between the bottom of the outer peripheral sidewall of the round cover and the annular plate. An alkaline absorbent is disposed above the annular plate. The liquid level of the alkaline absorbent is higher than the bottom of the outer peripheral sidewall of the round cover.

9. A method of using a VOCs waste gas treatment device, comprising utilizing the VOCs waste gas treatment device according to any one of claims 1-8, characterized in that, The usage method includes: Place the activated carbon block (305) into the adsorption box housing (302), open the electric valve (3021), and connect the external VOCs waste gas collection device to the air inlet pipe (102). When the liquid pump (106) on the spray cylinder (1) is started, the exhaust gas in the spray cylinder (1) will move into the first exhaust gas discharge pipe (2) by pressure difference diffusion. The electric valve (3021) is closed only when the activated carbon block (305) needs to be regenerated.

10. The method of using the VOCs waste gas treatment device according to claim 9, characterized in that, The regeneration process for activated carbon blocks (305) is as follows: Start the fan (702) and the electric heating column (704) in the heating chamber shell (701). The exhaust gas enters the heating chamber shell (701) from the exhaust gas guide pipe (5). After the exhaust gas is decomposed by the catalytic oxidation unit (7), a part of the exhaust gas is sent back to the adsorption box shell (302) through the hot air return pipe (6) to regenerate the activated carbon block (305).

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