Copper-based denitration catalyst preparation system

Abstract

The utility model relates to the technical field of denitration catalysts, in particular to a copper-based denitration catalyst preparation system. Comprising a precipitation reaction kettle, a feed port of the precipitation reaction kettle is respectively connected with a first raw material tank, a second raw material tank and a third raw material tank through pipelines, a discharge port of the precipitation reaction kettle is connected with a feed port of a multi-effect evaporator through a pipeline, and a discharge port of the multi-effect evaporator is connected with a mixer through a pipeline. According to the system provided by the utility model, the copper-based denitration catalyst is prepared in a deposition manner, so that active components, auxiliaries and a carrier can be uniformly mixed, and the activity and the stability of the catalyst are guaranteed; the system is simple in design, easy and convenient to operate, low in energy consumption and suitable for industrial large-scale production, the system can be connected with a downstream catalyst forming device, and industrial production of the copper-based denitration catalyst is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of denitration catalysts, in particular to a copper-based denitration catalyst preparation system. Background Art

[0002] Denitrification catalysts are widely used in denitrification projects in coal-fired power plants. Industrial denitrification catalysts are mainly vanadium-titanium based catalysts with an active temperature window of 320-420°C and a design life of 24,000 hours. Since 2015, the ultra-low emission transformation of coal-fired power plants has been smoothly promoted. At present, the dust, SO2 and nitrogen oxides (NO x ) emissions have reached the international advanced level. In order to further strengthen air pollution prevention and control, ultra-low emissions in non-electric industries such as steel, cement, and glass have been put on the agenda.

[0003] The flue gas temperature in the non-electricity industry is usually low (<300°C). If vanadium-titanium-based catalysts are used directly, excellent denitration effects cannot be achieved. For this reason, the development of new low-temperature denitration catalysts has become a research hotspot in the field of air pollution prevention and control. Among them, copper-based denitration catalysts have received high attention for their high and low-temperature denitration activity and low cost. In order to realize the industrial production of copper-based denitration catalysts, the catalyst preparation system must be developed simultaneously. Utility Model Content

[0004] The utility model aims to provide a copper-based denitration catalyst preparation system, which can evenly mix various raw materials, ensure the activity and stability of the copper-based denitration catalyst, and realize the industrial production of the copper-based denitration catalyst.

[0005] The utility model provides a copper-based denitration catalyst preparation system, comprising a precipitation reactor, wherein a feed port of the precipitation reactor is respectively connected to a first raw material tank, a second raw material tank and a third raw material tank through pipelines, a discharge port of the precipitation reactor is connected to a feed port of a multiple-effect evaporator through a pipeline, and a discharge port of the multiple-effect evaporator is connected to a mixer through a pipeline.

[0006] Furthermore, the steam outlet of the multiple-effect evaporator is connected to the first raw material tank through a pipeline.

[0007] Furthermore, a first pump is provided on the pipeline connecting the first raw material tank and the precipitation reactor.

[0008] Furthermore, a second pump is provided on the pipeline connecting the second raw material tank and the precipitation reactor.

[0009] Furthermore, a third pump is provided on the pipeline connecting the third raw material tank and the precipitation reactor.

[0010] Furthermore, a stirring device is provided in the first raw material tank.

[0011] Furthermore, the material in the first raw material tank is a mixture of molecular sieve and deionized water; the molecular sieve is one of SSZ-13, SAPO-34, and ZSM-5.

[0012] Furthermore, the material in the second raw material tank is a mixed solution of copper nitrate and an auxiliary agent; the auxiliary agent is one of cerium nitrate, manganese nitrate, yttrium nitrate and neodymium nitrate.

[0013] Furthermore, the material in the third raw material tank is an ammonia solution.

[0014] Furthermore, a binder and an extrusion aid are provided in the mixer; the binder is kaolin, and the extrusion aid is sesbania powder.

[0015] In summary, compared with the prior art, the utility model has the following advantages:

[0016] The technical solution of the utility model adopts a deposition precipitation method to complete the preparation of the copper-based denitration catalyst by setting a raw material tank, a precipitation reactor, a multi-effect evaporator and a mixer, so as to achieve uniform mixing of active components, additives and carriers, ensure the activity and stability of the catalyst, and the prepared copper-based denitration catalyst has a high denitration efficiency; the design is simple, the operation is easy, and it is suitable for industrial scale-up production. The system can be connected with a downstream catalyst forming device to realize the industrial production of the copper-based denitration catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the structure of the preparation system in the embodiment of the utility model.

[0019] Explanation of the reference numerals: 1 - first raw material tank; 2 - second raw material tank; 3 - third raw material tank; 4 - precipitation reactor; 5 - multi-effect evaporator; 6 - mixer; 7 - first pump; 8 - second pump; 9 - third pump. DETAILED DESCRIPTION

[0020] The technical solution of the utility model will be described clearly and completely in conjunction with the embodiments below. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0023] Example

[0024] A copper-based denitration catalyst preparation system, such as Figure 1 As shown, a precipitation reactor 4 is included, the feed port of the precipitation reactor 4 is connected to the first raw material tank 1, the second raw material tank 2, and the third raw material tank 3 through pipelines, the discharge port of the precipitation reactor 4 is connected to the feed port of the multiple-effect evaporator 5 through a pipeline, and the discharge port of the multiple-effect evaporator 5 is connected to the mixer 6 through a pipeline; the steam outlet of the multiple-effect evaporator 5 is connected to the first raw material tank 1 through a pipeline. A first pump 7 is provided on the pipeline connecting the first raw material tank 1 and the precipitation reactor 4; a second pump 8 is provided on the pipeline connecting the second raw material tank 2 and the precipitation reactor 4; a third pump 9 is provided on the pipeline connecting the third raw material tank 3 and the precipitation reactor 4; the materials are transported to the precipitation reactor 4 by the first pump 7, the second pump 8 and the third pump 9.

[0025] The first raw material tank 1 is provided with a stirring device, wherein the material is a mixture of molecular sieve and deionized water, and the solid-liquid ratio of the mixture is 1:20; the molecular sieve can be selected from SSZ-13, SAPO-34, and ZSM-5. The material in the second raw material tank 2 is a mixed solution of copper nitrate and an auxiliary agent, wherein the auxiliary agent is one of cerium nitrate, manganese nitrate, yttrium nitrate, and neodymium nitrate, wherein the molar ratio of the copper element in the mixed solution to the metal element in the auxiliary agent is 1:1-5:1. The material in the third raw material tank 3 is an ammonia solution.

[0026] At the same time, a binder and an extrusion aid can be added to the mixer 6. The binder can be kaolin, which is a substance required for subsequent catalyst molding and the added amount is 5-10% of the molecular sieve mass; the extrusion aid can be sesbania powder, which can play a lubricating role and the added amount of sesbania powder is 1-5% of the molecular sieve mass.

[0027] The method for preparing Cu-Mn / ZSM-5 catalyst using the above system is as follows:

[0028] S1. Add deionized water and ZSM-5 molecular sieve to the first raw material tank 1, start stirring at a speed of 600 rpm; add a mixed solution of copper nitrate and manganese nitrate to the second raw material tank 2, wherein the Cu / Mn molar ratio is 3:1; add 2 mol / L ammonia solution to the third raw material tank 3;

[0029] S2. The precipitation reactor 4 is heated to 75°C, the first pump 7, the second pump 8 and the third pump 9 are started, and the materials in the first raw material tank 1, the second raw material tank 2 and the third raw material tank 3 are injected into the precipitation reactor 4; the stirring of the precipitation reactor 4 is started at a speed of 1500 rpm, and the flow rate of the materials in the second raw material tank 2 and the third raw material tank 3 entering the precipitation reactor 4 is controlled by controlling the second pump 8 and the third pump 9 to ensure that the pH value of the mixed solution in the precipitation reactor 4 is 8±0.2;

[0030] S3. After 20 minutes of feeding, the first pump 7, the second pump 8 and the third pump 9 are turned off, and the material in the precipitation reactor 4 is stirred for 2 hours. After stirring, the product is transported to the multiple-effect evaporator 5, and the evaporated water is refluxed from the multiple-effect evaporator 5 to the first raw material tank 1, so as to realize the recycling of water and save water; the temperature of the multiple-effect evaporator 5 is controlled to 90-100°C to ensure that the moisture content of the solid material after evaporation is controlled at 25wt%;

[0031] S4. The solid material evaporated in the multi-effect evaporator 5 was transported to the mixer 6 for mixing, and kaolin and sesbania powder were added to the mixer 6. After mixing for 2h, Cu-Mn / ZSM-5 catalyst paste was obtained;

[0032] S5. The Cu-Mn / ZSM-5 catalyst paste in the mixer 6 is unloaded and transported to the downstream catalyst forming system.

[0033] Comparative Example

[0034] A method for preparing a Cu-Mn / ZSM-5 catalyst is prepared by an ion exchange method in the prior art, and the process is as follows:

[0035] (1) adding ZSM-5 molecular sieve to a mixed solution of copper nitrate and manganese nitrate, wherein the molar ratio of Cu / Mn is 3:1, stirring in a water bath at 80° C. for 4 h, then filtering and drying;

[0036] (2) The dried powder is added into a mixer, and kaolin, sesbania powder and deionized water are added at the same time. After mixing for 2 hours, a Cu-Mn / ZSM-5 catalyst paste is obtained.

[0037] In the embodiments and comparative examples, the mass fraction of CuO in the catalyst paste is 6%, and the mass fraction of MnO2 is 4%.

[0038] The catalyst paste prepared in the embodiment and the comparative example was dried, calcined at 400°C for 3h, and then tested for denitration performance. The test results are shown in Table 1. The test conditions are: NO concentration 500ppm, NH3 / NO=1, SO2 concentration 400ppm, H2O concentration 5vol%, N2 as balance gas, GHSV=200000h -1 .

[0039] Table 1 Denitrification performance of different catalysts

[0040]

[0041] It can be clearly seen from Table 1 that the Cu-Mn / ZSM-5 catalyst prepared by the system provided by the utility model has a denitration efficiency at 300° C., 400° C. and 500° C. that is significantly higher than that of the catalyst prepared in the comparative example.

[0042] The copper-based denitration catalyst preparation system provided by the utility model adopts a deposition precipitation method to complete the preparation of the copper-based denitration catalyst, which can achieve uniform mixing of active components, additives and carriers, ensure the activity and stability of the catalyst, and the prepared catalyst has a high denitration efficiency. The design is simple, the operation is easy, the amount of wastewater is small, and it is suitable for industrial scale-up production. The system can be connected to the downstream catalyst forming device to realize the industrial production of copper-based denitration catalysts.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A copper-based denitration catalyst preparation system, characterized in that: The invention comprises a precipitation reaction kettle (4), wherein the feed port of the precipitation reaction kettle (4) is respectively connected to a first raw material tank (1), a second raw material tank (2), and a third raw material tank (3) through pipelines, the discharge port of the precipitation reaction kettle (4) is connected to the feed port of a multiple-effect evaporator (5) through a pipeline, and the discharge port of the multiple-effect evaporator (5) is connected to a mixer (6) through a pipeline.

2. The preparation system according to claim 1, characterized in that: The steam outlet of the multiple-effect evaporator (5) is connected to the first raw material tank (1) through a pipeline.

3. The preparation system according to claim 1, characterized in that: A first pump (7) is provided on the pipeline connecting the first raw material tank (1) and the precipitation reaction kettle (4).

4. The preparation system according to claim 3, characterized in that: A second pump (8) is provided on the pipeline connecting the second raw material tank (2) and the precipitation reaction kettle (4).

5. The preparation system according to claim 4, characterized in that: A third pump (9) is provided on the pipeline connecting the third raw material tank (3) and the precipitation reaction kettle (4).

6. The preparation system according to claim 1, characterized in that: The first raw material tank (1) is provided with a stirring device.

7. The preparation system according to claim 1, characterized in that: The material in the first raw material tank (1) is a mixture of molecular sieve and deionized water; the molecular sieve is one of SSZ-13, SAPO-34 and ZSM-5.

8. The preparation system according to claim 7, characterized in that: The material in the second raw material tank (2) is a mixed solution of copper nitrate and an auxiliary agent; the auxiliary agent is one of cerium nitrate, manganese nitrate, yttrium nitrate and neodymium nitrate.

9. The preparation system according to claim 8, characterized in that: The material in the third raw material tank (3) is an ammonia solution.

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