Anti-clogging CO catalytic oxidation module and preparation process

Abstract

The invention discloses an anti-clogging CO catalytic oxidation module and a preparation technology, and relates to the technical field of sintering machine CO catalytic oxidation energy conservation and emission reduction technologies, the anti-clogging CO catalytic oxidation module comprises a catalyst module which is arranged in a combined mode, and the catalyst module comprises catalyst sheet layers and supporting columns; the catalyst modules are combined in one of double layers and multiple layers through catalyst sheet layers and supporting columns, and flue gas dredging and flow equalizing layers are formed between the adjacent catalyst sheet layers and between the adjacent catalyst modules; according to the present invention, the catalyst sheet layers and the support columns are arranged and combined with a plurality of layers and a plurality of layers so as to construct the brand new flue gas dredging and flow equalizing layer so as to re-uniformly distribute the flue gas between the adjacent catalyst sheet layers and between the adjacent bed layers, such that the dust is not easily attached to the catalyst surface, and the dust on the catalyst surface can be eliminated and can be reduced; the stable efficiency of the catalyst is kept, the service life of the catalyst is prolonged, and the CO catalytic oxidation efficiency can be improved through the uniformity of airflow.

Description

Technical Field

[0001] The invention relates to the technical field of energy saving and emission reduction of CO catalytic oxidation of sintering machines, and in particular to an anti-clogging CO catalytic oxidation module and a preparation process thereof. Background Art

[0002] The steel industry is one of the main sources of atmospheric pollutants CO. The sintering process has high carbon emissions. A large amount of CO is discharged into the atmosphere with flue gas, seriously affecting air quality and causing energy loss. It is extremely urgent to carry out sintering machine flue gas CO treatment and emission reduction.

[0003] Since 2019, although the research and development of CO catalytic oxidation catalyst modules has been effective, it is affected by various factors and the problem of dust clogging is prominent. The traditional catalyst module has a single and inflexible layout, and the channels are easily blocked by dust and are easily poisoned. Blockage will cause the catalyst to fail, reduce catalytic efficiency, obstruct flue gas circulation, and even cause failure shutdown and fan damage.

[0004] In view of this, this application is hereby filed. Summary of the invention

[0005] The object of the present invention is to provide an anti-clogging CO catalytic oxidation module and a preparation process to solve the problems mentioned in the above background technology that the traditional catalyst module has a single and inflexible layout, flue gas dust easily blocks the channels, the catalyst is easily poisoned, the catalyst is cracked and damaged inside, the catalytic efficiency is low, and the service life is short.

[0006] To solve the above technical problems, the present invention provides an anti-clogging CO catalytic oxidation module and a preparation process, comprising a combined catalyst module, wherein the catalyst module comprises a catalyst sheet and a support column, the catalyst sheet is a honeycomb structure, the support column is a hollow columnar structure, the catalyst module is an integrated calcined structure, the catalyst module is combined in a double layer or a multi-layer manner through the catalyst sheet and the support column, and a flue gas diversion and equalizing flow layer is formed between adjacent catalyst sheets and adjacent catalyst modules; the catalyst sheet is a traditional catalyst formed by equidistant segments according to a cross section, the catalyst sheet and the support column are extruded after mixing catalyst raw materials, the catalyst is a nano-titanium dioxide active component, and the carrier is an alumina carrier.

[0007] Furthermore, the preparation method of the titanium dioxide active component is as follows: tetrabutyl titanate is used as a precursor and dissolved in ethanol, stirred and water and hydrochloric acid are added dropwise to form a sol, stirred into a gel, aged at room temperature, supercritically dried to obtain a dry gel, and calcined to obtain a nano titanium dioxide active component; the preparation method of the alumina carrier is as follows: the silicon dioxide carrier is stirred in a toluene solution of 3-aminopropyltriethoxysilane, filtered for washing with toluene, and then dried to obtain an amino functional group modified carrier, the alumina carrier is stirred in a nitric acid solution at room temperature, washed with water to neutrality, and then dried to obtain an acid-treated carrier that is conducive to the adsorption of the active component.

[0008] Furthermore, the catalyst sheet layer and the support column are made into a catalyst module by mixing catalyst raw materials and an adhesive.

[0009] Furthermore, the opening rate of the catalyst layer is between 65% and 85%.

[0010] A preparation process for an anti-clogging CO catalytic oxidation module, characterized in that it comprises the following steps: step 1: mixing catalyst raw materials and extruding them to obtain catalyst sheets and support columns; step 2: drying the catalyst sheets and support columns and calcining them as a whole to obtain a catalyst module, and combining the catalyst sheets in a double-layer or multi-layer manner to obtain a catalyst unit module; step 3: drying the catalyst unit module and feeding it into a catalyst calcining kiln to obtain a finished product.

[0011] Furthermore, in the step 1, the catalyst layer and the support column are independently extruded and formed.

[0012] Furthermore, in the step 2, the catalyst sheet layer and the support column are made into a catalyst module using a catalyst mixed raw material and an adhesive.

[0013] Furthermore, in step three, the finished product is an anti-clogging CO catalytic oxidation module.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. Through the combination of catalyst sheets and support columns with multiple layer heights and multiple / multi-level layer arrangements, a new flue gas diversion and uniform flow layer is constructed to redistribute the flue gas evenly between adjacent catalyst sheets and adjacent bed layers, so that dust is not easy to adhere to the catalyst surface, and the accumulation of dust on the catalyst surface is eliminated and reduced. Even if there is a temporary blockage in a certain channel, it will not cause the reaction loss of the catalyst surface in the lower channel, and will not occupy the active points on the surface of the next catalyst layer, so as to maintain the stable efficiency of the catalyst and extend the service life of the catalyst. The uniformity of the airflow helps to improve the CO catalytic oxidation efficiency; 2. The flue gas diversion and equalizing layer reduces the flue gas velocity, which is beneficial to the diffusion of the flue gas and reorganization into the next level of catalyst sheet or bed. This modular structure can minimize the flow area of ​​local hole blockage. When a certain channel is blocked, the flue gas diversion and equalizing layer will redistribute the flue gas to the adjacent or other channels of the hole to avoid the blockage of the entire channel caused by the blockage of a single long channel. Compared with the traditional integral catalyst, the catalyst sheet is more convenient and flexible in layout and module assembly; 3. Avoid the clogging of the catalyst caused by the attachment of flue gas dust, avoid the long-term clogging of traditional catalysts by dust erosion and poisoning of the catalyst, the blocked channels cannot be circulated by flue gas, the local temperature rises suddenly, and avoids the uneven heat storage that is not released, resulting in local cracking and damage of the catalyst, which greatly improves the service life of the catalyst; 4. The active component of nano-titanium dioxide has high catalytic activity and chemical stability. Its unique nano-size effect can provide more active sites, enhance the adsorption and activation ability of CO molecules, and thus effectively promote the catalytic oxidation reaction of CO. Alumina is used as a carrier. Alumina has a large specific surface area and good thermal stability. It can evenly disperse the active components of nano-titanium dioxide to prevent them from agglomerating, further improve the utilization rate and catalytic efficiency of the active components, and provide a stable physical support structure for the reaction, ensuring that the catalyst maintains good performance during long-term use, reducing the problem of catalytic performance degradation caused by changes in the carrier structure, etc., which is conducive to improving the catalytic performance and service life of the entire catalyst module, so that it can play a more excellent role in the anti-blocking CO catalytic oxidation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of an anti-clogging CO catalytic oxidation module in operation; Figure 2 Schematic diagram of the structure of an anti-clogging CO catalytic oxidation module Figure 1 ; Figure 3 Schematic diagram of the structure of an anti-clogging CO catalytic oxidation module Figure 2 ; Figure 4 Schematic diagram of the structure of an anti-clogging CO catalytic oxidation module Figure 3 ; Figure 5 A schematic diagram of the structure of a support column of an anti-clogging CO catalytic oxidation module; Figure 6 A schematic diagram of a method for laying and assembling an anti-clogging CO catalytic oxidation module; Figure 7 This is a system diagram for the arrangement of an anti-clogging CO catalytic oxidation module in a CO catalytic oxidation bed.

[0016] In the figure: 1. Catalyst sheet; 2. Support column; 3. Catalyst module; 4. Flue gas diversion and equalizing layer. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-Figure 7 The present invention provides a technical solution: an anti-clogging CO catalytic oxidation module, comprising a catalyst module 3 arranged in combination, the catalyst module 3 comprising a catalyst sheet 1 and a support column 2, the catalyst sheet 1 is a honeycomb structure, the support column 2 is a hollow columnar structure, the catalyst module 3 is an integrated calcined structure, the catalyst module 3 is combined by the catalyst sheet 1 and the support column 2 in a double layer or a multilayer, and a flue gas diversion uniform flow layer 4 is formed between adjacent catalyst sheets 1 and adjacent catalyst modules 3; the catalyst sheet 1 is a traditional catalyst formed by equidistant sections according to a cross section, the catalyst sheet 1 and the support column 2 are extruded after mixing catalyst raw materials, the catalyst is a nano titanium dioxide active component, and the carrier is an alumina carrier; the titanium dioxide active component is prepared as follows: tetrabutyl titanate is used as a precursor and dissolved in ethanol, stirred and water and hydrochloric acid are added dropwise to form a sol, stirred into a gel, aged at room temperature, supercritically dried to obtain a dry gel, and calcined to obtain a nano titanium dioxide active component; the alumina carrier is prepared as follows: the silicon dioxide carrier is 3- The toluene solution of aminopropyltriethoxysilane is stirred, filtered, washed with toluene and then dried to obtain an amino functional group modified carrier; the alumina carrier is stirred at room temperature in a nitric acid solution, washed with water until neutral and then dried to obtain an acid-treated carrier that is conducive to the adsorption of active components; the catalyst layer 1 and the support column 2 are made into a catalyst module 3 by using a catalyst mixed raw material and an adhesive; the opening rate of the catalyst layer 1 is between 65% and 85%, which fully guarantees the contact area between the flue gas and the catalyst.

[0019] The primary function of the flue gas diversion and equalizing layer 4 is to grade the flue gas flow and buffer the flow rate, so that the flue gas flow is more uniform, which is equivalent to each of the catalyst layers 1 being a first-level grid airflow uniform distribution plate. The more grades there are within the allowed range, the more uniform the airflow is; when the flue gas flow diffuses unimpeded in the diversion and equalizing layer, the flue gas flow rate slowly decreases, increasing the residence time of the flue gas catalytic oxidation, making its reaction more complete, reducing CO emissions while generating higher thermal efficiency; secondly, the flue gas catalytic oxidation process is an exothermic chemical reaction, and due to the above-mentioned flue gas homogenization, the temperature rise and diffusion of the flue gas flow are more stable, avoiding damage to the catalyst due to local uneven heating and increasing the service life of the catalyst; thirdly, the uniformity of the airflow decomposes the local accumulation of dust, and the dust in the flue gas is evenly integrated into the flue gas flow, and the flow of dust reduces its adhesion and hanging on the catalyst surface, so the role it plays can be regarded as a self-cleaning function.

[0020] Nano-titanium dioxide active components have high catalytic activity and chemical stability. Its unique nano-size effect can provide more active sites, enhance the adsorption and activation ability of CO molecules, and thus effectively promote the catalytic oxidation reaction of CO. Alumina is used as a carrier. Alumina has a large specific surface area and good thermal stability. It can evenly disperse the nano-titanium dioxide active components to prevent them from agglomerating, further improve the utilization rate and catalytic efficiency of the active components, and provide a stable physical support structure for the reaction, ensuring that the catalyst maintains good performance during long-term use, reducing the problem of catalytic performance degradation caused by changes in the carrier structure, etc., which is conducive to improving the catalytic performance and service life of the entire catalyst module, so that it can play a more excellent role in the anti-blocking CO catalytic oxidation process.

[0021] A preparation process of an anti-clogging CO catalytic oxidation module comprises the following steps: Step 1: Mix the catalyst raw materials and extrude them to obtain a catalyst sheet 1 and a support column 2, wherein the catalyst sheet 1 and the support column 2 are independently extruded; Step 2: drying the catalyst sheet 1 and the support column 2 and then calcining them as a whole to obtain a catalyst module 3; the catalyst sheet 1 and the support column 2 are made into a catalyst module 3 using a catalyst mixed raw material and a binder; the catalyst sheet 1 is combined into a double layer or a multi-layer to obtain a catalyst unit module; Step 3: After drying the catalyst unit module, send it into a catalyst calcining kiln to obtain a finished product, which is an anti-clogging CO catalytic oxidation module.

[0022] It should be noted here that the catalyst layer 1 is a flue gas reaction bed layer, which catalytically oxidizes CO. CO reacts with oxygen to convert into carbon dioxide (CO2). This reaction not only eliminates CO pollution in the flue gas, but also releases a large amount of heat energy. From the perspective of energy conservation, emission reduction and economic benefits, the application of the CO catalytic oxidation module helps enterprises achieve green production and sustainable development by reducing energy consumption and pollutant emissions. At the same time, the heat energy released during the catalytic oxidation reaction can be recycled. Through the heat recovery system, this heat energy can be used to increase the flue gas temperature to meet the temperature requirements for the denitrification reaction, thereby reducing the energy consumption of heating equipment such as hot blast furnaces. Specifically, the catalytic reaction can increase the flue gas temperature by 15-35°C, which is of great significance for reducing blast furnace gas consumption and saving energy. Due to the recovery of heat energy and the improvement of denitrification efficiency, enterprises can also obtain certain economic benefits.

[0023] Working principle: The anti-clogging CO catalytic oxidation module is composed of a plurality of catalyst modules 3, which are arranged in a specific manner so that a flue gas diversion and uniform flow layer 4 is formed between adjacent catalyst sheets 1 and between adjacent catalyst modules 3. The design of the flue gas diversion and uniform flow layer 4 ensures that the flue gas can be evenly and stably distributed to each catalyst module 3, aiming to optimize the flow of flue gas in the module, reduce the risk of clogging, avoid uneven catalytic efficiency or clogging caused by excessively high or low local flue gas concentration, and improve catalytic efficiency.

[0024] Each catalyst module 3 is composed of a catalyst sheet 1 and a support column 2. The catalyst sheet 1 is designed as a honeycomb structure, which provides a large surface area and is conducive to the full contact between the flue gas and the catalyst. The support column 2 is a hollow columnar structure, which not only provides the necessary structural support, but also helps to reduce material usage and reduce costs. The catalyst module 3 adopts an integrated calcined structure to ensure a firm bond between the catalyst sheet 1 and the support column 2.

[0025] The catalyst layer 1 and the support column 2 are both made by extrusion molding after mixing the catalyst raw materials. The catalyst is a nano-titanium dioxide active component, and the carrier is an alumina carrier. The opening rate of the catalyst layer 1 is set to 75%, which is within the recommended range of 65%-85%, ensuring sufficient contact area between the flue gas and the catalyst, while also facilitating the smooth flow of the flue gas, enhancing the adsorption and activation ability of CO molecules, and being able to evenly disperse the nano-titanium dioxide active component to prevent it from agglomerating, further improving the utilization rate and catalytic efficiency of the active component, and reducing the problems of decreased catalytic performance due to changes in the carrier structure, which is beneficial to improving the catalytic performance and service life of the entire catalyst module 3.

[0026] When the flue gas contacts the catalyst layer 1, CO is oxidized into carbon dioxide (CO2) under the action of the catalyst. The active components of the catalyst can reduce the activation energy of CO oxidation, thereby accelerating the reaction process. Due to the high porosity of the catalyst layer 1 and the good flue gas diversion design, sufficient contact and efficient conversion of CO and the catalyst are ensured.

[0027] The catalyst module 3 can be combined in double layers or multiple layers to form a larger catalytic oxidation unit module. This modular design not only facilitates installation and maintenance, but also provides good scalability, and the size and number of the catalytic oxidation modules can be adjusted according to actual needs.

[0028] Preparation process of anti-clogging CO catalytic oxidation module: Step 1: Raw material mixing and molding: The catalyst raw materials (including active components, support materials and possible additives) are mixed uniformly in a predetermined proportion.

[0029] The mixed catalyst raw materials are extruded into honeycomb-shaped catalyst sheets 1 and hollow column-shaped support columns 2 using an extrusion molding device. The two components are molded independently to ensure that their respective shapes and sizes meet the design requirements.

[0030] Step 2: Drying and integrated calcination: The formed catalyst sheet layer 1 and support column 2 are placed in a drying device for thorough drying to remove moisture and volatile substances.

[0031] After drying, the catalyst sheet 1 and the support column 2 are combined with an adhesive (such as an organic resin or an inorganic adhesive) to form a catalyst module 3. Then, the entire catalyst module 3 is sent to a catalyst calcining kiln for integrated calcination. The calcination process is intended to cause a chemical reaction between the catalyst raw materials, form a stable catalytic structure, and enhance the bonding force between the catalyst sheet 1 and the support column 2.

[0032] As required, a plurality of catalyst modules 3 may be combined in double layers or multiple layers to form a catalyst unit module.

[0033] Step 3: Final calcination and finished product preparation: The assembled catalyst unit module is dried again to remove moisture that may have been introduced during the assembly process.

[0034] After drying, the catalyst unit module is sent to the catalyst calcination kiln for final calcination treatment. This step is to further consolidate the catalyst structure and improve its catalytic performance and anti-clogging ability.

[0035] After calcination, the finished product is taken out, which is the anti-clogging CO catalytic oxidation module. This module has an optimized flue gas diversion and flow-balancing layer 4 design, which can effectively reduce the risk of blockage and improve the catalytic efficiency. Reference Figure 1 When the pores of one of the catalyst sheets 1 enter the dust block and become clogged, the flue gas will be redistributed to the adjacent or other pores of the pores through the flue gas diversion and equalizing layer 4, avoiding the blockage of the entire channel caused by the blockage of a single long pore. Compared with the traditional integral catalyst, the catalyst sheet 1 is more convenient and flexible in layout and assembly, and has changed the overall structure of the traditional catalyst. It is composed of a catalyst sheet 1 and a support column 2 with a variety of layer heights and a variety of / multi-level layer arrangements, which makes it difficult for flue gas dust to adhere to the catalyst surface and hang on the surface of the catalyst pores, maintaining the catalyst's stable efficiency and extending the catalyst's service life. The flue gas diversion and equalizing layer 4 redistributes the flue gas evenly in the adjacent bed layers, and the uniformity of the airflow helps to improve the CO catalytic oxidation efficiency.

[0036] Reference Figure 5 The support column 2 is a hollow column, which can be a rectangular hollow column or a circular hollow column as shown in the figure. The hollow in the middle is just staggered with the honeycomb holes of the catalyst layer 1, which is convenient for the smooth flow of flue gas. The support column 2 is used to support and connect the upper and lower catalyst layers 1, and the material used is the same as that of the catalyst layer 1.

[0037] Reference Figure 6 , the laying and assembly method of the anti-clogging CO catalytic oxidation module: according to the design requirements, the catalyst module 3 can be arranged in multiple layers, with the bottom layer as the first layer, called the base layer, and multiple layers can be arranged upward. The first layer (base layer) is laid diagonally from a corner of the assembly box, and the second layer is laid in the opposite direction of the first layer. Each of the above layers is laid in the opposite direction of the next layer until it reaches the top layer. This method is based on the relative hole requirements of the catalyst finished layer, and the laying effect is flat and orderly, and there is no need to adjust the gap after laying.

[0038] Reference Figure 7 The arrangement of the anti-clogging CO catalytic oxidation module in the CO catalytic oxidation bed usually has a reserved spare layer in the flue gas denitrification link. The flue gas flow direction of the CO catalytic oxidation bed is the same as that of the previous flue gas denitrification. The flue gas in the catalytic oxidation bed catalytically oxidizes CO, and CO reacts with oxygen to be converted into carbon dioxide (CO2), thereby achieving the goal of removing CO from the flue gas. In this process, the heat energy generated by the oxidation reaction is recovered to heat the flue gas.

Claims

1. An anti-clogging CO catalytic oxidation module, characterized in that: The invention comprises a catalyst module (3) which is arranged in combination, wherein the catalyst module (3) comprises a catalyst sheet (1) and a support column (2), the catalyst sheet (1) being a honeycomb structure, the support column (2) being a hollow columnar structure, the catalyst module (3) being an integrated calcined structure, the catalyst module (3) being combined in a double layer or a multilayer manner through the catalyst sheet (1) and the support column (2), and a flue gas diversion uniform flow layer (4) being formed between adjacent catalyst sheets (1) and adjacent catalyst modules (3); the catalyst sheet (1) is a conventional catalyst formed by equidistantly segmenting according to a cross section, the catalyst sheet (1) and the support column (2) being formed by extrusion after mixing catalyst raw materials, the catalyst being a nano titanium dioxide active component, and the carrier being an alumina carrier.

2. The anti-clogging CO catalytic oxidation module according to claim 1, characterized in that: The preparation method of the titanium dioxide active component is as follows: tetrabutyl titanate is used as a precursor and dissolved in ethanol, stirred and water and hydrochloric acid are added dropwise to form a sol, stirred into a gel, aged at room temperature, supercritically dried to obtain a dry gel, and calcined to obtain a nano titanium dioxide active component; the preparation method of the alumina carrier is as follows: the silicon dioxide carrier is stirred in a toluene solution of 3-aminopropyltriethoxysilane, filtered for washing with toluene, and then dried to obtain an amino functional group modified carrier, the alumina carrier is stirred in a nitric acid solution at room temperature, washed with water until neutral, and then dried to obtain an acid-treated carrier that is conducive to the adsorption of the active component.

3. The anti-clogging CO catalytic oxidation module according to claim 1, characterized in that: The catalyst sheet layer (1) and the support column (2) are manufactured into a catalyst module (3) by using a catalyst mixed raw material and an adhesive.

4. The anti-clogging CO catalytic oxidation module according to claim 1, characterized in that: The open porosity of the catalyst layer (1) is between 65% and 85%.

5. A preparation process for an anti-clogging CO catalytic oxidation module, characterized in that: The following steps are involved: Step 1: Mixing the catalyst raw materials and extruding them into a shape to obtain a catalyst sheet (1) and a support column (2); Step 2: drying the catalyst sheet (1) and the support column (2), and then calcining them in an integrated manner to obtain a catalyst module (3); combining the catalyst sheet (1) in a double-layer or multi-layer manner to obtain a catalyst unit module; Step 3: Dry the catalyst unit module and send it into the catalyst calcining kiln to obtain the finished product.

6. The process for preparing a blockage-resistant CO catalytic oxidation module according to claim 5, characterized in that: In the step 1, the catalyst layer (1) and the support column (2) are independently extruded and formed.

7. The process for preparing a blockage-resistant CO catalytic oxidation module according to claim 5, characterized in that: In the second step, the catalyst sheet layer (1) and the support column (2) are made into a catalyst module (3) using a catalyst mixed raw material and an adhesive.

8. The process for preparing a blockage-resistant CO catalytic oxidation module according to claim 5, characterized in that: In step three, the finished product is an anti-clogging CO catalytic oxidation module.

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