High-efficiency zero-short-circuit organic waste gas catalytic combustion device

Abstract

This utility model belongs to the field of environmental protection equipment, specifically relating to a high-efficiency zero-short-circuit catalytic combustion device for organic waste gas. It includes a shell of a catalytic combustion chamber, with an air intake mechanism connected to the top and an exhaust pipe connected to the bottom. Inside the shell, from top to bottom, are sequentially arranged an air intake grille mechanism for uniformly transporting waste gas, a non-precious metal catalytic mechanism, a first precious metal catalytic mechanism, and a second precious metal catalytic mechanism. The air intake grille mechanism is connected to the air intake mechanism. This method utilizes the device of this utility model, which solves the problems of catalyst bed short-circuiting in traditional catalytic combustion devices. It achieves a tiered distribution of overall thermal energy, uniform temperature field, and uniform airflow field, improving catalyst utilization, reducing the risk of catalyst poisoning, and ultimately achieving the goal of improving VOCs purification efficiency and ensuring long-term stable operation.

Description

Technical Field

[0001] This utility model belongs to the field of environmental protection equipment, specifically relating to a high-efficiency zero-short-circuit catalytic combustion device for organic waste gas. Background Technology

[0002] The "Comprehensive Treatment Plan for Volatile Organic Compounds in Key Industries" clearly requires that the waste gas treatment efficiency of industries such as petrochemicals and coating be ≥90%.

[0003] There are various existing technologies for treating volatile organic compounds (VOCs), such as condensation, absorption, direct combustion, adsorption, and catalytic combustion. Among these, catalytic combustion has become the mainstream choice due to its balance between energy consumption and purification efficiency. However, existing catalytic combustion devices still have the following technical shortcomings in the VOC treatment process:

[0004] (1) Traditional catalytic combustion devices suffer from uneven airflow distribution between multi-layer catalyst beds, local overheating leading to catalyst sintering, and insufficient catalyst utilization in edge areas, resulting in short circuits in the catalyst bed and a decrease in VOCs conversion rate (generally <90%).

[0005] (2) Directly loading precious metal catalysts into the catalytic combustion device can cause catalyst poisoning due to certain components in the exhaust gas;

[0006] (3) Currently, the catalytic combustion chamber is set with a single-stage bed, and the catalyst is usually thick. The VOCs concentration at the exhaust gas inlet is high, and the exhaust gas reacts quickly with the catalyst near the top. When it enters the bottom catalyst, the exhaust gas concentration is too low, resulting in insufficient reaction driving force, low catalyst utilization and low VOCs conversion rate.

[0007] In view of the above, this utility model is hereby proposed. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and propose a high-efficiency zero-short-circuit catalytic combustion device for organic waste gas. This device achieves graded distribution of thermal energy, uniform distribution of temperature field and airflow field, improves catalyst utilization, reduces the risk of catalyst poisoning, and ultimately achieves the goal of improving VOCs purification rate and ensuring long-term stable operation.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] This utility model provides a high-efficiency zero-short-circuit catalytic combustion device for organic waste gas, characterized in that it includes a shell of a catalytic combustion chamber, an air intake mechanism connected to the top of the shell, and an exhaust pipe connected to the bottom. Inside the shell, from top to bottom, are arranged a series of components for uniformly transporting waste gas: an air intake grille mechanism, a non-precious metal catalytic mechanism, a first precious metal catalytic mechanism, and a second precious metal catalytic mechanism. The air intake grille mechanism is connected to a branch pipe of the air intake mechanism. The air intake mechanism includes a main pipe connected to the outer wall of the shell, and multiple branch pipes connected to the side of the main pipe. The non-precious metal catalytic mechanism, from top to bottom, includes a non-metallic catalyst layer, a first fixed bed support mesh, and a first swirl plate. Both the first fixed bed support mesh and the first swirl plate are connected to the inner wall of the shell.

[0011] Furthermore, the air intake grille mechanism includes an air delivery component horizontally disposed inside the housing. The air delivery component is composed of multiple pipes connected to form a grille structure. The air intake grille mechanism also includes multiple spiral nozzles uniformly installed on each pipe. The branch pipe passes through the housing and communicates with the multiple pipes for uniformly delivering exhaust gas into the housing.

[0012] Furthermore, the number of branch pipes is four, and the gas transmission assembly consists of four pipes connected together to form a grid structure, with each branch pipe connected to the intersection of the corresponding grid structure below it.

[0013] Furthermore, each of the branch pipes is equipped with a regulating valve, and any one of the regulating valves is linked with a corresponding thermocouple installed in the lower part of the housing through a control system. The thermocouple is located below the second noble metal catalytic mechanism.

[0014] Furthermore, the first swirl plate adopts an axial helical blade structure.

[0015] Furthermore, the non-metallic catalyst layer includes at least one catalyst module covered with a first fixed bed support network, the catalyst module being made of honeycomb-shaped non-precious metal catalyst.

[0016] Furthermore, the first noble metal catalytic mechanism and the second noble metal catalytic mechanism have the same structure;

[0017] The first noble metal catalytic mechanism includes a first noble metal catalyst layer, a second fixed bed support network, and a second swirl plate arranged sequentially from top to bottom. Both the second fixed bed support network and the second swirl plate are connected to the inner wall of the shell.

[0018] Furthermore, a manhole is provided on the outer wall of the shell, and the manhole is located above the non-precious metal catalytic mechanism, the first precious metal catalytic mechanism and the second precious metal catalytic mechanism.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) The present invention provides a high-efficiency zero-short-circuit organic waste gas catalytic combustion device. By setting an air intake grille mechanism in the shell, the waste gas is injected into the catalytic combustion chamber in multiple areas. In addition, by setting a regulating valve on each branch pipe of the air intake grille mechanism, the effect of uniform air intake is achieved, which solves the problem of short circuit in the catalyst bed caused by uneven waste gas distribution.

[0021] 2) The present invention provides a high-efficiency zero-short-circuit organic waste gas catalytic combustion device, which adopts a 1+2 multi-stage mode by setting a non-precious metal catalytic mechanism, a first precious metal catalytic mechanism and a second precious metal catalytic mechanism. The front end is set with a first stage of non-precious metal catalyst and the last two stages are set with precious metal catalyst. The staged setting can realize the redistribution of airflow on the one hand, and disperse the combustion heat on the other hand, avoiding the catalyst layer overheating under high concentration of organic waste gas.

[0022] In detail, by setting up a honeycomb-shaped non-precious metal catalyst, which preferentially adsorbs substances such as sulfides (H2S), halogens (Cl⁻), and siloxanes, the problem of catalyst poisoning is solved;

[0023] The precious metal catalyst layer is arranged in two stages with a temperature equalization zone in the middle (i.e., in the interval area between the two precious metal catalyst layers, the exhaust gas can be fully mixed in the interval area through the guidance of the swirl plate, thereby achieving the effect of temperature equalization). By distributing the reaction heat in multiple stages, the temperature of each bed is controlled, avoiding the temperature rise of a single bed and the large amount of heat release that could lead to local overheating and catalyst sintering. At the same time, it avoids the problems of insufficient reaction driving force, low catalyst utilization and low VOCs conversion rate caused by a thick single-stage catalyst bed. In addition, it can reduce the airflow resistance of the equipment, reduce airflow scouring loss, and prevent catalyst carrier breakage, achieving a triple breakthrough of "high efficiency, low energy consumption and long life".

[0024] 3) This utility model provides a high-efficiency zero-short-circuit catalytic combustion device for organic waste gas. Each catalyst bed is equipped with a swirl plate. To generate a tangential velocity component in the airflow, radial diffusion is achieved through centrifugal force, resulting in redistribution of the waste gas. This solves the problem of velocity differences across the bed cross-section and insufficient catalyst utilization in the edge region caused by traditional straight-inflow airflow. The swirl plate adopts an axial spiral blade type, resulting in lower pressure drop and easier processing. Attached Figure Description

[0025] The accompanying drawings are incorporated in and form part of this specification, and together with the description, serve to explain the principles of this invention.

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of the organic waste gas catalytic combustion device of this utility model;

[0028] Figure 2 This is a top view of the organic waste gas catalytic combustion device of this utility model;

[0029] Figure 3 This is a partial structural diagram of the air intake grille mechanism in the organic waste gas catalytic combustion device of this utility model;

[0030] Figure 4 This is a schematic diagram of the swirl plate structure in the organic waste gas catalytic combustion device of this utility model.

[0031] In the diagram: 1 is the catalytic combustion chamber; 2 is the air intake mechanism; 3 is the exhaust pipe; 4 is the thermocouple; 5 is the manhole; 6 is the pressure transmitter; 11 is the housing; 12 is the air intake grille mechanism; 13 is the non-precious metal catalytic mechanism; 14 is the first precious metal catalytic mechanism; 15 is the second precious metal catalytic mechanism; 21 is the main pipe; 22 is the branch pipe; 23 is the regulating valve; 121 is the gas delivery assembly; 122 is the spiral nozzle; 131 is the non-metallic catalyst layer; 132 is the first fixed bed support network; 133 is the first swirl plate; 141 is the first precious metal catalyst layer; 142 is the second fixed bed support network; 143 is the second swirl plate; 1211 is the pipe. Detailed Implementation

[0032] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this invention. Rather, they are merely examples of apparatuses consistent with some aspects of this invention as detailed in the appended claims.

[0033] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Example

[0034] Please see Figures 1-4This utility model provides a high-efficiency zero-short-circuit organic waste gas catalytic combustion device, including a shell 11 of a catalytic combustion chamber 1. The top of the shell 11 is connected to an air intake mechanism 2, and the bottom is connected to an exhaust pipe 3. The interior of the shell 11 is provided with an air intake grille mechanism 12 for uniformly transporting waste gas, a non-precious metal catalytic mechanism 13, a first precious metal catalytic mechanism 14, and a second precious metal catalytic mechanism 15 arranged sequentially from top to bottom. The air intake grille mechanism 12 is connected to the air intake mechanism 2.

[0035] The air intake grille mechanism 12 includes an air delivery component 121 horizontally connected inside the housing 11. The air delivery component 121 is composed of multiple pipes 1211 connected to form a grille structure. The air intake grille mechanism 12 also includes multiple spiral nozzles 122 uniformly installed on each pipe. The branch pipe 22 of the air intake mechanism 2 passes through the housing 11 and communicates with the multiple pipes 1211 to uniformly deliver exhaust gas into the housing 11.

[0036] like Figure 2 As shown, the air intake mechanism 2 includes a main pipe 21, which is connected to the outer wall of the housing 11. There are multiple branch pipes 22, which are all connected to the side of the main pipe 21 and communicate with it.

[0037] like Figure 3 As shown, there are 4 branch pipes 22. The gas transmission assembly 121 is composed of 4 pipes connected to form a grid structure. Each branch pipe 22 is connected to the intersection of the grid structure below it. This position is optimal. Each pipe can be connected to both horizontal and vertical pipes at the same time. Alternatively, it can be connected to a single pipe. This is not limited here.

[0038] Specifically, in this embodiment, the main pipe 21 is welded to the upper part of the catalytic combustion chamber 1, but only serves as a support channel and is not connected to the interior of the catalytic combustion chamber 1. The waste gas to be treated enters through the main pipe 21 and is diverted through four branch pipes 22. The branch pipes 22 pass through the top of the shell 11 and connect with the intersection of the grid-shaped pipes. The waste gas to be treated enters the grid-shaped pipes through the branch pipes 22 and is finally sprayed into the interior of the shell 11 from the spiral nozzle 42 for catalytic combustion treatment.

[0039] like Figure 1 and 2 As shown, each of the branch pipes 22 is equipped with a regulating valve 23. Any of the regulating valves 23 is linked with a corresponding thermocouple 4 installed in the lower part of the housing 11 through a control system. The thermocouple 4 is located below the second noble metal catalytic mechanism 15.

[0040] It should be noted that the control system is a PLC or DCS control system, which is existing technology and will not be elaborated here.

[0041] Specifically, in this embodiment, when a thermocouple 4 below the housing 11 detects that the temperature is too high, the PLC control system obtains the information and sends a control signal to the regulating valve 23 corresponding to the thermocouple 4 to control the opening of the regulating valve 23 (which can be a pneumatic regulating valve), reduce the flow of exhaust gas, and prevent the temperature in the area where the thermocouple 4 is located from being too high.

[0042] Furthermore, the non-precious metal catalytic mechanism 13 is provided with a non-metallic catalyst layer 131, a first fixed bed support network 132 and a first swirl plate 133 in sequence from top to bottom. The first fixed bed support network 132 and the first swirl plate 133 are both welded to the inner wall of the shell 11.

[0043] Specifically, in this embodiment, the non-metallic catalyst layer 131 includes at least one catalyst module that covers the first fixed bed support net 132. The catalyst module is made of honeycomb non-precious metal catalyst with dimensions of 100mm×100mm×50mm. Each honeycomb non-precious metal catalyst is connected to the other by a high-temperature sealing rope and a high-temperature sealing adhesive to ensure the sealing between adjacent catalysts.

[0044] like Figure 4 As shown, the first swirl plate 133 adopts an axial spiral blade structure to disperse combustion heat and avoid overheating of the catalyst layer under high concentration of organic waste gas.

[0045] Furthermore, the first noble metal catalytic mechanism 14 and the second noble metal catalytic mechanism 15 have the same structure and the same connection method with the housing 11;

[0046] The first noble metal catalytic mechanism 14 includes a first noble metal catalyst layer 141, a second fixed bed support net 142, and a second swirl plate 143 arranged sequentially from top to bottom. The second fixed bed support net 142 and the second swirl plate 143 are both welded to the inner wall of the shell 11.

[0047] like Figure 1 As shown, a manhole 5 is provided on the outer wall of the housing 11, and the manhole 5 is located above the non-precious metal catalytic mechanism 13, the first precious metal catalytic mechanism 14 and the second precious metal catalytic mechanism 15.

[0048] Specifically, in this embodiment, the manhole 5 is connected to the catalytic combustion chamber 1. The manhole 5 can be opened and closed for maintenance and replacement of the catalyst, allowing the catalyst module to enter and exit.

[0049] Furthermore, a thermocouple 4 and a pressure transmitter 6 are installed on the outer wall of the housing 11. The thermocouple 4 and the pressure transmitter 6 are located between the non-precious metal catalytic mechanism 13 and the first precious metal catalytic mechanism 14, and between the first precious metal catalytic mechanism 14 and the second precious metal catalytic mechanism 15.

[0050] Furthermore, both the first noble metal catalyst layer 141 and the second noble metal catalyst layer of the second noble metal catalytic mechanism 15 include at least one catalyst module, which covers the entire second fixed bed support network 142 and is specifically composed of multiple sub-catalyst modules connected together. The number of catalyst module layers is determined by the actual operating conditions.

[0051] Specifically, in this embodiment, the catalyst is installed in a modular manner. The sub-catalyst modules contained in the catalyst module are arranged in a staggered manner, and high-temperature sealing ropes and high-temperature sealant are used to bond them at the staggered joints to ensure the sealing between the sub-catalyst modules.

[0052] Furthermore, the top of the housing 11 is provided with a rupture port, and the bottom is provided with a support structure for fixing or connecting with other equipment.

[0053] The process for treating waste gas using this device is as follows:

[0054] Step 1: The waste gas to be treated is sent into multiple branch pipes 22 through the main pipe 21 of the air intake mechanism 2, and then the gas is evenly sent into the housing 11 through the spiral nozzle 122 through the air intake grille mechanism 12 connected to the multiple branch pipes 22.

[0055] Step 2: After the waste gas to be treated undergoes catalytic combustion reaction through the non-precious metal catalytic unit 13, the first precious metal catalytic unit 14, and the second precious metal catalytic unit 15, it is discharged through the exhaust pipe 3.

[0056] During steps 1 and 2, the thermocouple 4 monitors the temperature of its area in real time and uploads the temperature to the PLC control system. When the thermocouple 4 detects a temperature exceeding 400°C, the PLC control system controls the opening of the regulating valve 23 above the thermocouple 4 to reduce the amount of organic waste gas entering.

[0057] The above description is merely a specific embodiment of this utility model, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this utility model.

[0058] It should be understood that this utility model is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of this utility model is limited only by the appended claims.

Claims

1. A high efficiency zero short circuit organic waste gas catalytic combustion device, characterized in that, The housing (11) includes a catalytic combustion chamber (1). An intake mechanism (2) is connected to the top of the housing (11), and an exhaust pipe (3) is connected to the bottom. Inside the housing (11), from top to bottom, are arranged an intake grille mechanism (12) for uniformly distributing exhaust gas, a non-precious metal catalytic mechanism (13), a first precious metal catalytic mechanism (14), and a second precious metal catalytic mechanism (15). The intake grille mechanism (12) is connected to a branch pipe (22) of the intake mechanism (2). The air intake mechanism (2) includes a main pipe (21), which is connected to the outer wall of the housing (11). There are multiple branch pipes (22), which are all connected to the side of the main pipe (21). The non-precious metal catalyst mechanism (13) is provided with a non-metallic catalyst layer (131), a first fixed bed support network (132) and a first swirl plate (133) from top to bottom. The first fixed bed support network (132) and the first swirl plate (133) are both connected to the inner wall of the housing (11).

2. The high efficiency zero short circuit organic waste gas catalytic combustion device according to claim 1, characterized in that, The air intake grille mechanism (12) includes an air delivery assembly (121) horizontally arranged inside the housing (11). The air delivery assembly (121) is composed of multiple pipes (1211) connected to form a grille structure. The air intake grille mechanism (12) also includes multiple spiral nozzles (122) evenly installed on each pipe. The branch pipe (22) passes through the housing (11) and communicates with the multiple pipes (1211) for uniformly delivering exhaust gas into the housing (11).

3. The high-efficiency zero-short-circuit catalytic combustion device for organic waste gas according to claim 1, characterized in that, The number of branch pipes (22) is 4. The gas transmission assembly (121) is composed of 4 pipes connected to form a grid structure. Each branch pipe (22) is connected to the intersection of the grid structure below it.

4. The high efficiency zero short circuit organic waste gas catalytic combustion device according to claim 1, characterized in that, Each of the branch pipes (22) is equipped with a regulating valve (23), and any one of the regulating valves (23) is linked with a corresponding thermocouple (4) installed in the lower part of the housing (11) through a control system. The thermocouple (4) is located below the second noble metal catalytic mechanism (15).

5. The high efficiency zero short circuit organic waste gas catalytic combustion device according to claim 1, characterized in that, The first swirl plate (133) adopts an axial helical blade structure.

6. The high-efficiency zero-short-circuit catalytic combustion device for organic waste gas according to claim 1, characterized in that, The non-metallic catalyst layer (131) includes at least one catalyst module covered by the first fixed bed support network (132), the catalyst module being made of honeycomb non-precious metal catalyst.

7. The high efficiency zero short circuit organic waste gas catalytic combustion device according to claim 1, characterized in that, The first noble metal catalytic mechanism (14) and the second noble metal catalytic mechanism (15) have the same structure; The first noble metal catalytic mechanism (14) includes a first noble metal catalyst layer (141), a second fixed bed support network (142), and a second swirl plate (143) arranged sequentially from top to bottom. The second fixed bed support network (142) and the second swirl plate (143) are both connected to the inner wall of the shell (11).

8. The high efficiency zero short circuit organic waste gas catalytic combustion device according to claim 1, characterized in that, The outer wall of the housing (11) is provided with manholes (5), and the manholes (5) are all located above the non-precious metal catalytic mechanism (13), the first precious metal catalytic mechanism (14) and the second precious metal catalytic mechanism (15).

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