Preparation system of flat plate denitration catalyst
Patent Information
- Application Number
- CN202522287591.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-29
- Publication Date
- 2026-09-22
- Estimated Expiration
- 2035-10-29
AI Technical Summary
然而，现有催化剂制备系统在实现活性组分均匀负载、控制煅烧工艺参数等方面存在一定不足，例如浸渍液分散不均、煅烧温度场波动等，导致难以精确调控催化剂表面活性中心的结构与分布，从而影响催化剂在保证高脱硝效率的同时有效抑制SO2氧化的能力
1、本实用新型的平板式脱硝催化剂的制备系统，包括料罐、对压辊、第一烘干单元、浸渍液罐、第二烘干单元、不锈钢钢网和牵引辊部件，其中，料罐用于装填储存催化剂膏料，催化剂膏料输送到不锈钢钢网上后，不锈钢钢网及不锈钢钢网上的催化剂膏料在牵引辊部件的支撑和张紧作用下，输送至对压辊处，由对压辊将催化剂膏料压制在不锈钢钢网上，压制后的含催化剂膏料的不锈钢钢网进一步进入第一烘干单元，由第一烘干单元将催化剂膏料进行预烘干，预烘干后的含催化剂膏料的不锈钢钢网进一步进入浸渍液罐，使得催化剂得到活性组分的充分浸渍，浸渍后的催化剂进一步采用第二烘干单元进行彻底烘干，制得平板式脱硝催化剂。该系统通过“先成型载体，后负载活性组分”的设计，实现了活性组分在催化剂表层的选择性、梯度化分布，进而使得催化还原NOx的活性中心主要集中在表面，而内部载体缺少将SO2氧化为SO3的活性位点。也即通过物理方式缩小了SO2氧化反应的有效区域，从而在保证高脱硝效率的同时，显著抑制了SO2的非选择性氧化，从源头上减少了硫酸氢铵的生成量，延长了催化剂的使用寿命；
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Figure CN224777765U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of denitrification catalyst production and preparation technology, and in particular to a preparation system for a plate-type denitrification catalyst. Background Technology
[0002] With increasingly stringent environmental protection requirements, controlling nitrogen oxide emissions from coal-fired power plants, steel mills, cement plants, and other industrial kilns has become increasingly important. Selective catalytic reduction (SCR) technology is currently a widely used and highly efficient denitrification technology, with its core component being the denitrification catalyst. Under sulfur-containing flue gas conditions, traditional vanadium-based catalysts, while catalytically reducing nitrogen oxides, also oxidize some SO2 to SO3, which then reacts with escaped ammonia to form ammonium bisulfate. This substance is highly viscous and easily crystallizes, readily causing blockage of catalyst pores and clogging and corrosion of downstream air preheaters, affecting the safe operation of the system.
[0003] To reduce SO2 oxidation rates, the industry is actively developing new denitrification catalysts. Among them, plate-type catalysts have gained attention due to their advantages such as resistance to ash blockage and wear. However, existing catalyst preparation systems have certain shortcomings in achieving uniform loading of active components and controlling calcination process parameters. For example, uneven dispersion of the impregnation solution and fluctuations in the calcination temperature field make it difficult to accurately control the structure and distribution of active centers on the catalyst surface, thus affecting the catalyst's ability to effectively suppress SO2 oxidation while ensuring high denitrification efficiency.
[0004] Therefore, there is an urgent need in the existing technology for a dedicated system that can stably prepare plate-type denitrification catalysts with low SO2 oxidation rate. By optimizing and integrating the key preparation device, the performance of the catalyst product can be stably controlled, thereby fundamentally reducing the SO2 oxidation rate, extending the catalyst's service life, and ensuring the long-term stable operation of the denitrification system.
[0005] In view of this, this utility model is proposed. Utility Model Content
[0006] The purpose of this invention is to provide a preparation system for a flat-plate denitrification catalyst, which reduces the amount of ammonium bisulfate generated at the source and extends the service life of the catalyst.
[0007] This invention provides a flat-plate denitrification catalyst preparation system, comprising a material tank, a pressure roller, a first drying unit, an impregnation liquid tank, a second drying unit, a stainless steel mesh, and a traction roller assembly. The pressure roller is located downstream of the discharge port of the material tank; The first drying unit is located downstream of the pressure rollers; The impregnation tank is located downstream of the first drying unit; The second drying unit is located downstream of the impregnation tank; The stainless steel mesh is sequentially threaded through the pressure rollers, the first drying unit, the impregnation tank, and the second drying unit, and is supported and tensioned by the traction roller assembly, so that the stainless steel mesh forms a continuous conveying path.
[0008] In a preferred embodiment of this technical solution, a quantitative conveying valve is provided at the outlet end of the material tank, and the pressure roller is located downstream of the quantitative conveying valve.
[0009] In a preferred embodiment of this technical solution, the pressure roller includes a driving roller and a driven roller, and the stainless steel mesh is disposed between the driving roller and the driven roller.
[0010] As a preferred embodiment of this technical solution, the first drying unit and / or the second drying unit are tunnel-type or box-type structures.
[0011] As a preferred embodiment of this technical solution, in the first drying unit and the second drying unit, heating elements are provided above and / or below the stainless steel mesh.
[0012] In a preferred embodiment of this technical solution, the traction roller assembly includes a first traction roller, a second traction roller, a third traction roller, and a fourth traction roller. The first traction roller is located in front of the inlet of the impregnation tank and is used to guide the stainless steel mesh downward into the impregnation tank. The second and third traction rollers are arranged side by side below the liquid level inside the impregnation tank to support the stainless steel mesh so that it passes horizontally through the impregnation liquid. The fourth traction roller is located after the outlet of the impregnation tank and is used to guide the stainless steel mesh upward away from the impregnation tank.
[0013] As a preferred embodiment of this technical solution, the stainless steel mesh is a flexible metal woven mesh.
[0014] As a preferred embodiment of this technical solution, the first drying unit is provided with at least three independent temperature control zones along the traveling direction of the stainless steel mesh.
[0015] As a preferred embodiment of this technical solution, it further includes a winding device, which is located downstream of the second drying unit.
[0016] As a preferred embodiment of this technical solution, it further includes a central controller, and the heating elements in the first drying unit and the second drying unit, the motors of the quantitative conveying valve and the traction roller component are all connected to the central controller via signal lines.
[0017] The preparation system for the flat-plate denitration catalyst of this invention has at least the following beneficial effects: 1. The preparation system for the flat-plate denitrification catalyst of this utility model includes a material tank, a counter-pressure roller, a first drying unit, an impregnation liquid tank, a second drying unit, a stainless steel mesh, and a traction roller assembly. The material tank is used to fill and store catalyst paste. After the catalyst paste is conveyed to the stainless steel mesh, the stainless steel mesh and the catalyst paste on it are conveyed to the counter-pressure roller under the support and tension of the traction roller assembly. The counter-pressure roller presses the catalyst paste onto the stainless steel mesh. The pressed stainless steel mesh containing catalyst paste further enters the first drying unit, where the catalyst paste is pre-dried. The pre-dried stainless steel mesh containing catalyst paste further enters the impregnation liquid tank, allowing the catalyst to be fully impregnated with the active components. The impregnated catalyst is then thoroughly dried in the second drying unit to obtain the flat-plate denitrification catalyst. This system, through the design of "first forming the carrier, then loading the active components," achieves selective and gradient distribution of active components on the catalyst surface, thereby enhancing the catalytic reduction of NO. x The active centers are mainly concentrated on the surface, while the internal support lacks active sites for oxidizing SO2 to SO3. This physically reduces the effective area for SO2 oxidation, thus significantly inhibiting non-selective SO2 oxidation while maintaining high denitrification efficiency, reducing the amount of ammonium bisulfate generated at the source, and extending the catalyst's lifespan. 2. This utility model integrates units such as conveying, continuous pressing, precise drying, and controllable impregnation, forming an automated and continuous production line. It overcomes the shortcomings of existing preparation systems in terms of the uniformity of active component loading and the control of key process parameters, ensuring a high degree of consistency and stability in the performance of catalyst products in each batch and each region. The process is simple, easy to operate, and suitable for large-scale industrial production. Attached Figure Description
[0018] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the preparation system for the plate-type denitrification catalyst of this utility model; Figure 2 This is a schematic diagram of the control method of the central controller in the preparation system of the plate-type denitrification catalyst of this utility model.
[0020] Figure label: 1: Material tank; 2: Quantitative conveying valve; 3: Catalyst paste; 4: Pressure roller; 5: First drying unit; 6: First traction roller; 7: Second traction roller; 8: Third traction roller; 9: Fourth traction roller; 10: Impregnation liquid tank; 11: Second drying unit; 12: Flat plate denitrification catalyst; 13: Central controller; 14: Heating element of the first drying unit; 15: Heating element of the second drying unit; 16: Servo motor; 17: Stainless steel mesh. Detailed Implementation
[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0022] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0023] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0024] Example like Figure 1 As shown, this embodiment provides a flat-plate denitrification catalyst preparation system, including a material tank 1, a counter-pressure roller 4, a first drying unit 5, an impregnation liquid tank 10, a second drying unit 11, a stainless steel mesh 17, and a traction roller assembly. The counter-pressure roller 4 is located downstream of the discharge port of the material tank 1; the first drying unit 5 is located downstream of the counter-pressure roller 4; the impregnation liquid tank 10 is located downstream of the first drying unit 5; the second drying unit 11 is located downstream of the impregnation liquid tank 10; the stainless steel mesh 17 is sequentially passed through the counter-pressure roller 4, the first drying unit 5, the impregnation liquid tank 10, and the second drying unit 11, and is supported and tensioned by the traction roller assembly, so that the stainless steel mesh 17 forms a continuous conveying path.
[0025] In this embodiment, the material tank 1 is used to fill and store the catalyst paste 3. The stainless steel mesh 17 is located below the material tank 1. After the catalyst paste 3 is conveyed onto the stainless steel mesh 17, the stainless steel mesh 17 and the catalyst paste 3 on the stainless steel mesh 17 are conveyed to the pressure roller 4 under the support and tension of the traction roller component. The pressure roller 4 presses the catalyst paste 3 onto the stainless steel mesh 17. The pressed stainless steel mesh 17 containing the catalyst paste 3 further enters the first drying unit 5, where the catalyst paste 3 is pre-dried. The pre-dried stainless steel mesh 17 containing the catalyst paste 3 further enters the impregnation tank 10, so that the catalyst is fully impregnated with the active components. The impregnated catalyst is further thoroughly dried by the second drying unit 11 to obtain the flat plate denitrification catalyst 12.
[0026] This system, through a design of "first forming the support, then loading the active component," achieves selective and gradient distribution of the active component on the catalyst surface, thereby enhancing the catalytic reduction of NO. x The active centers are mainly concentrated on the surface, while the internal carrier lacks active sites for oxidizing SO2 to SO3. This physically reduces the effective area for SO2 oxidation, thus significantly inhibiting non-selective SO2 oxidation while maintaining high denitrification efficiency. This reduces the amount of ammonium bisulfate generated at the source. This reduction in ammonium bisulfate generation directly avoids adhesion, crystallization, and blockage of ammonium bisulfate in the catalyst channels and downstream air preheater, effectively mitigating the resulting increase in system resistance and equipment corrosion, ensuring the long-term, efficient, and stable operation of the denitrification system and the entire industrial production plant. Furthermore, the relatively reduced amount of ammonium bisulfate deposition lessens physical coverage and chemical damage to the catalyst's active sites, significantly extending catalyst lifespan and reducing replacement frequency and operating costs.
[0027] Furthermore, in this embodiment, a stainless steel mesh 17 is used as the core carrier and conveyor belt, and the pressure roller 4 is used to press the catalyst, resulting in a robust three-dimensional structure with the stainless steel mesh 17 as the skeleton. This structure endows the catalyst with excellent mechanical strength and has anti-clogging and wear-resistant properties, making it particularly suitable for flue gas environments with high dust concentrations.
[0028] Based on the above technical solution, and more preferably, a quantitative conveying valve 2 is provided at the outlet end of the material tank 1, and the pressure roller 4 is located downstream of the quantitative conveying valve 2. The catalyst paste 3 in the material tank 1 is conveyed to the downstream stainless steel mesh 17 through the quantitative conveying valve 2. The stainless steel mesh 17 is pulled forward to the pressure roller 4 under the traction of the traction roller component, and the pressure roller 4 presses the catalyst paste 3 onto the stainless steel mesh 17.
[0029] Specifically, the catalyst paste 3 is composed of TiO2, inorganic binder, organic binder, lubricant, glass fiber and water, with a water content of 30wt%~40wt%; wherein, the inorganic binder is one of attapulgite, sepiolite, clay and vermiculite; the organic binder is one of polyethylene oxide and polyethylene glycol; and the lubricant is one of guar gum powder and methylcellulose.
[0030] Based on the above technical solution, the pressure roller 4 specifically includes a driving roller and a driven roller, with a stainless steel mesh 17 disposed between the driving roller and the driven roller, passing directly through the gap between the driving roller and the driven roller. When the paste falls onto the stainless steel mesh 17, it immediately enters the biting area of the pressure roller 4 to crush the catalyst paste 3 covering the stainless steel mesh 17 from both the top and bottom sides, making it dense, flat, and firmly attached to the membrane pores of the stainless steel mesh 17.
[0031] In this embodiment, the first drying unit 5 and / or the second drying unit 11 are tunnel-type or box-type structures, with a stainless steel mesh 17 running through them. Inside the first drying unit 5 and / or the second drying unit 11, heating elements (such as infrared heating tubes) are arranged above and / or below the stainless steel mesh 17. The stainless steel mesh 17 carries the pressed catalyst and is uniformly heated during its slow passage through the first drying unit 5, achieving an initial reduction in moisture content; for example, the moisture content of the catalyst paste 3 on the dried stainless steel mesh 17 is 5wt%~10wt%. During its slow passage through the second drying unit 11, it is uniformly heated, achieving complete removal of physical water and some crystal water.
[0032] In this embodiment, more preferably, the traction roller assembly includes a first traction roller 6, a second traction roller 7, a third traction roller 8, and a fourth traction roller 9. The first traction roller 6 is located before the inlet of the impregnation tank 10 and is used to guide the stainless steel mesh 17 downward into the impregnation tank 10. The second traction roller 7 and the third traction roller 8 are arranged side by side below the liquid surface inside the impregnation tank 10 and are used to support the stainless steel mesh 17 so that it passes horizontally through the impregnation liquid, thereby ensuring that the catalyst carrier on the stainless steel mesh 17 has enough time to fully contact the impregnation liquid and complete the loading of the active component. The fourth traction roller 9 is located after the outlet of the impregnation tank 10 and is used to guide the stainless steel mesh 17 upward away from the impregnation tank 10.
[0033] Specifically, the impregnation tank 10 contains a mixture of ammonium metavanadate, ammonium heptamolybdate, and / or ammonium paratungstate. In addition, depending on the formulation, it may also contain additives such as rare earth elements and transition metal elements.
[0034] In this embodiment, the stainless steel mesh 17 is a flexible metal woven mesh, and its specific aperture size and shape can be selected according to actual needs.
[0035] Based on the above technical solution, and further preferably, along the traveling direction of the stainless steel mesh 17, the interior of the first drying unit 5 is provided with at least three independent temperature control zones, specifically including an inlet low-temperature zone, an intermediate medium-temperature zone, and an outlet high-temperature zone. The set temperature of the inlet low-temperature zone is lower than that of the intermediate medium-temperature zone, and the set temperature of the intermediate medium-temperature zone is lower than that of the outlet high-temperature zone. By setting temperature zones with gradient heating, the moisture in the catalyst paste 3 can be removed smoothly, avoiding cracks or pores caused by rapid surface crusting leading to the escape of internal water vapor. This significantly improves the mechanical strength and yield of the catalyst blank, solving the problems of "calcination temperature field fluctuations" and "difficulty in precise control" in the prior art.
[0036] Based on the above technical solution, and more preferably, it also includes a winding device, which is located downstream of the second drying unit 11. The winding device is used to wind the stainless steel mesh 17 carrying the shaped flat catalyst, and then perform subsequent pleating and cutting, and calcining in the calcining furnace to obtain the flat low SO2 oxidation rate denitrification catalyst.
[0037] like Figure 2 As shown, in another specific embodiment of this utility model, the system is further equipped with a central controller 13. The heating elements, quantitative conveying valves 2, and motors of the traction roller components in the first drying unit 5 and the second drying unit 11 are all connected to the central controller 13 via signal lines. The central controller 13 (such as a PLC) coordinates the operation of the system according to preset process parameters. Its control logic includes: controlling the conveying amount of catalyst paste 3 by adjusting the opening of the quantitative conveying valve 2; controlling the power of the heating elements 14 of the first drying unit and the heating elements 15 of the second drying unit by collecting feedback signals from temperature sensors to maintain the set temperature of each temperature zone; and setting and stabilizing the conveying speed of the stainless steel mesh 17 by controlling the rotation speed of the servo motor 16 driving the traction roller component. Through the coordinated control of the central controller 13, the uniformity of the active component loading, the accurate and stable drying temperature curve, and the constant production speed can be ensured, thereby ensuring that the final catalyst product has high denitrification efficiency and low SO2 oxidation rate from the overall process perspective. In this embodiment, the setting of the central controller 13 and its control method for other components can refer to the prior art, and will not be described in detail here.
[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A preparation system for a flat-plate denitration catalyst, characterized in that, Includes a material tank, pressure rollers, a first drying unit, an impregnation liquid tank, a second drying unit, a stainless steel mesh, and traction roller components. The pressure roller is located downstream of the discharge port of the material tank; The first drying unit is located downstream of the pressure rollers; The impregnation tank is located downstream of the first drying unit; The second drying unit is located downstream of the impregnation tank; The stainless steel mesh is sequentially threaded through the pressure rollers, the first drying unit, the impregnation tank, and the second drying unit, and is supported and tensioned by the traction roller assembly, so that the stainless steel mesh forms a continuous conveying path.
2. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, The outlet end of the material tank is equipped with a quantitative conveying valve, and the pressure roller is located downstream of the quantitative conveying valve.
3. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, The pressure rollers include a driving roller and a driven roller, and the stainless steel mesh is disposed between the driving roller and the driven roller.
4. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, The first drying unit and / or the second drying unit are tunnel-type or box-type structures.
5. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, In the first drying unit and the second drying unit, heating elements are provided above and / or below the stainless steel mesh.
6. The preparation system for the flat-plate denitration catalyst according to claim 1, characterized in that, The traction roller assembly includes a first traction roller, a second traction roller, a third traction roller, and a fourth traction roller. The first traction roller is located in front of the inlet of the impregnation tank and is used to guide the stainless steel mesh downward into the impregnation tank. The second and third traction rollers are arranged side by side below the liquid level inside the impregnation tank to support the stainless steel mesh so that it passes horizontally through the impregnation liquid. The fourth traction roller is located after the outlet of the impregnation tank and is used to guide the stainless steel mesh upward away from the impregnation tank.
7. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, The stainless steel mesh is a flexible woven metal mesh.
8. The preparation system for the flat-plate denitrification catalyst according to claim 1, characterized in that, Along the direction of travel of the stainless steel mesh, the interior of the first drying unit is provided with at least three independent temperature control zones.
9. The preparation system for the plate-type denitrification catalyst according to claim 1, characterized in that, It also includes a winding device located downstream of the second drying unit.
10. The preparation system for the flat-plate denitrification catalyst according to claim 2, characterized in that, It also includes a central controller, and the heating elements in the first and second drying units, the quantitative conveying valve, and the motor of the traction roller component are all connected to the central controller via signal lines.