WO2019154093A1 - Scr honeycomb denitration catalyst and preparation method therefor - Google Patents

Abstract

An SCR honeycomb denitration catalyst and a preparation method therefor. The catalyst is prepared from a raw material comprising the following components: titanium dioxide, carboxymethyl cellulose, polyethylene oxide, fiber, deionized water, ammonium metavanadate, ammonium metatungstate, aqueous ammonia, lactic acid, cerium nitrate hexahydrate, and praseodymium nitrate hexahydrate, wherein the relation between the diameter R of the fiber and the average particle size d50 of the titanium dioxide is R=3-8d50; the relation between the fiber length L at the diameter R and the particle size d of the titanium dioxide is L=5000-6000d, the value range of d is d10-d90; the ratio of the adding mass m1 of the fiber to the adding mass m2 of the titanium dioxide is m1:m2＝0.06-0.15:1. The preparation method for the catalyst comprises mixing, molding, drying, and calcination. The crack generation rate in a drying process of the SCR honeycomb denitration catalyst prepared by fiber optimization selection is significantly reduced, and the mechanical strength of the finished product is remarkably improved.

Description

SCR honeycomb type denitration catalyst and preparation method thereof Technical field

The invention relates to an SCR honeycomb type denitration catalyst and a preparation method thereof, and belongs to the technical field of SCR catalysts.

Background technique

The denitrification transformation of thermal power plants in China has been completed, and the SCR honeycomb denitration catalyst currently used has undergone the first cycle. From the point of view of use, a large amount of catalyst is broken due to poor mechanical properties, which is detrimental to the regeneration of the catalyst.

In the preparation process of SCR honeycomb catalyst, certain fibers are added, including Rp-chop, wood pulp, glass fiber, etc., which play the role of pore-forming, increasing the toughness of the body and the mechanical strength of the finished product. The effect of the fiber is affected by the particle size of the substrate. great influence.

At present, for the improvement of the mechanical strength of the denitration catalyst, the optimization methods adopted are all focused on the types and amounts of raw materials. For example, Chinese patent CN201510043079.0 discloses an RP-CHOP denitration catalyst fiber. By preparing a novel SCR denitration catalyst, the catalyst prepared by calcination is invariant, does not generate cracks, and increases the service life of the catalyst.

At present, there is no effective design method that utilizes the existing fiber to optimize the mechanical strength and other properties of the denitration catalyst. In the preparation process of denitration catalyst, the fiber is still dominated by non-specific scale, while the particle size of the main substrate titanium dioxide (content greater than 85%) is within a range of distribution, as shown in Figure 1, it is difficult to make the existing denitration catalyst Performance is optimal.

Therefore, there is a need to find a simpler and more economical way to increase the mechanical strength of SCR honeycomb catalysts and maximize the efficiency of materials such as fibers.

Summary of the invention

In view of the above drawbacks in the prior art, the object of the present invention is to provide an SCR honeycomb type denitration catalyst and a preparation method thereof, and to establish a relationship between fiber diameter, length and addition amount and titanium dioxide particle size, thereby improving SCR honeycomb type denitration catalyst. Mechanical strength.

The invention is implemented by the following technical solutions:

An SCR honeycomb type denitration catalyst made of a raw material comprising the following components:

100 to 150 parts of titanium dioxide, 8 to 20 parts of carboxymethyl cellulose, 5 to 10 parts of polyethylene oxide, 6 to 22.5 parts of fiber, 50 to 80 parts of deionized water, 5 to 15 parts of ammonium metavanadate, and tungsten 10 to 20 parts of ammonium acid, 30 to 55 parts of ammonia water, 10 to 20 parts of lactic acid, 1 to 5 parts of cerium nitrate hexahydrate, and 0.1 to 1.5 parts of cerium nitrate hexahydrate;

Wherein, the relationship between the diameter R of the fiber and the average particle size d ₅₀ of the titanium dioxide is R=3 to 8d ₅₀ ; the relationship between the fiber length L at the diameter R and the particle size d of the titanium dioxide is L=5000 to 6000d, and the value of d is in the range of d ₁₀ ~ d _90; additional mass ratio of the additional mass m ₁ and m fiber is titanium dioxide _{2 m 1: m 2 = 0.06 ~} 0.15: 1.

Further, the particle size d of the titanium dioxide is normally distributed, and correspondingly, the fiber length L at the diameter R is normally distributed.

Further, the fiber type is Rp-chop, wood pulp, glass fiber, wherein Rp-chop and wood pulp can be mixed or added separately, and the glass fiber is a must-add fiber.

The invention also provides a preparation method of the SCR honeycomb type denitration catalyst as described above, comprising the following steps:

(1) Mixing: Including the following small steps:

a) dry mixing: 100 to 150 parts of titanium dioxide, 8 to 20 parts of carboxymethyl cellulose and 5 to 10 parts of polyethylene oxide are mixed into a mixer, adding 6 to 22.5 parts of fiber, and mixing;

b) Wet mixing: continue to add 50-80 parts of deionized water, 5-15 parts of ammonium metavanadate, 10-20 parts of ammonium metatungstate, 30-55 parts of ammonia water, 10-20 parts of lactic acid, 1-5 parts of nitric acid铈 hexahydrate and 0.1 to 1.5 parts of cerium nitrate hexahydrate, stirred;

c) dehumidification: the dehumidification equipment draws out the water vapor in the mixer;

(2) Molding: In turn, the following small steps are included:

d) filtering the material obtained in the small step c) with a filter plate to leave a material having a particle diameter smaller than the mesh of the filter plate, and preparing the filtered material into a desired shape;

e) placing the material of the above shape into an extruder and extruding;

(3) Drying: Including the following small steps:

f) One drying: it takes 8 to 11 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 30 ° C to 70 ° C, the blowing frequency increases from 15 Hz to 60 Hz, and the air humidity drops from 80% to 10%;

g) secondary drying: it takes 14 hours, during which the drying conditions are satisfied: the ambient temperature rises from 35 ° C to 60 ° C;

(4) Calcination: Including the following small steps:

h) heating stage: it takes 14 to 18 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from room temperature to 650 ° C;

i) Cooling phase: It takes 7-9 hours. During this period, the cooling conditions are satisfied: the ambient temperature drops from 650 °C to room temperature.

Further, in the small step c), the finally obtained material has a water content of 25% to 30%.

Further, in the small step d), the filter plate used is an SCR porous catalyst wet embryo extrusion filter plate: comprising equidistantly arranged metal strips, further comprising reinforcing ribs, the reinforcing ribs are perpendicular to the metal strips, the reinforcing ribs and the metal The strips are secured together to form a filter plate body.

Further, in the small step d), the spacing between adjacent metal strips of the filter plate is 0.4-0.6 mm.

Further, in the small step f), the following stages are included:

The first stage: it takes 3-4 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 30 °C to 40 °C, the air supply frequency rises from 15 Hz to 30 Hz, and the air humidity drops from 80% to 70%;

The second stage: it takes 3-4 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 40 °C to 60 °C, the air supply frequency increases from 30 Hz to 40 Hz, and the air humidity drops from 70% to 40%;

The third stage: it takes 2-3 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 60 ° C to 70 ° C, the supply frequency increases from 40 Hz to 60 Hz, and the air humidity drops from 40% to 10%.

Further, in the small step g), the finally obtained material has a water content of 5% to 10%.

Further, in the small step h), the following stages are included:

The first temperature rising phase: takes 7-9 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from room temperature to 400 ° C;

The second temperature rising phase: takes 7-9 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from 400 ° C to 650 ° C.

The beneficial effects of the invention are: according to the following principle, the fixed length of the fiber can only produce a better effect on the titanium dioxide particles of the corresponding particle size, and the effect of the titanium dioxide powder of other particle sizes is significantly weakened, which will result in the toughness of the catalyst body is not strong, It is easy to generate cracks during the drying process, so the mechanical strength of the finished product after calcination is also affected to some extent.

(1) The present invention establishes a relationship between fiber diameter, length and addition amount and titanium dioxide particle size.

(2) By analyzing the particle size distribution of denitrification titanium dioxide, selecting the fiber within the parameter range according to the above relationship to prepare the SCR honeycomb denitration catalyst, and the crack generation rate during the drying process of the SCR honeycomb denitration catalyst prepared by fiber optimization selection Significantly reduced, the mechanical strength of the finished product is significantly improved.

(3) According to the relationship between the established fiber diameter, length and addition amount and the titanium dioxide particle size, the invention accurately controls the specific parameters and operation methods in each process by mixing, forming, drying and calcining processes, and obtains high Performance of SCR Honeycomb Denitration Catalyst.

DRAWINGS

Figure 1 is a graph showing the particle size distribution of denitrated titanium dioxide.

Detailed ways

In order to make the objects and technical solutions of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings. The experimental methods described in the following examples are all conventional methods unless otherwise specified; the specific techniques or conditions are not indicated in the examples, according to the techniques or conditions described in the literature in the field or according to the product specifications; The reagents and materials are commercially available unless otherwise stated.

Titanium dioxide is a special titanium dioxide for denitration catalyst, and the particle size d of titanium dioxide is normally distributed.

In order to avoid repetition, the raw materials and preparation condition parameters involved in the present embodiment are collectively described as follows, and will not be described in detail in the specific embodiments:

Titanium dioxide 1000-1500kg, carboxymethyl cellulose 80～200kg, polyoxyethylene 50～100kg, fiber 60～225kg, deionized water 500～800kg, ammonium metavanadate 50～150kg, ammonium metatungstate 100～200kg, 300 to 550 kg of ammonia water, 100 to 200 kg of lactic acid, 10 to 50 kg of cerium nitrate hexahydrate, and 1 to 15 kg of cerium nitrate hexahydrate;

The specific steps of the preparation method are as follows:

Titanium dioxide, carboxymethyl cellulose and polyethylene oxide were added to the mixer to mix well, and the fibers were added and stirred for 5 minutes at a rotation speed of 200 r/min. Add deionized water, ammonium metavanadate, ammonium metatungstate, ammonia, lactic acid, cerium nitrate hexahydrate, cerium nitrate hexahydrate, stir for 25 min; open the dehumidification equipment, dehumidify for 35 min, and finally obtain the moisture content of the material. 25 to 30%.

The material is filtered by SCR porous catalyst wet embryo extrusion filter plate, leaving the material with particle size smaller than the filter plate mesh, and the filtered material is subjected to mud treatment; the processed material is placed in an extruder and extruded; The formed material is placed in a dry kiln car with a wet end automation device, and the dry kiln car is transferred to a dry room by a forklift, and the first stage of drying is taken for 3-4 days, during which the ambient temperature From 30 ° C to 40 ° C, the air supply frequency rises from 15 Hz to 30 Hz, the air humidity drops from 80% to 70%; enters the second phase of a dry 3-4 days, during which the ambient temperature is from 40 ° C When it rises to 60 °C, the air supply frequency rises from 30 Hz to 40 Hz, and the air humidity drops from 70% to 40%. It enters the third stage of drying, which takes 2-3 days, during which the ambient temperature rises from 60 °C to 70. °C, the air supply frequency rises from 40Hz to 60Hz, and the air humidity drops from 40% to 10%. After the end of one drying, the dry kiln car is transferred to the wet end automation equipment by the forklift. The equipment will put the material code on the dry kiln car to the secondary drying kiln car. After the code is completed, the secondary drying kiln car will be transported by the forklift. During the second drying, a secondary drying took 14 hours, during which the ambient temperature rose from 35 ° C to 60 ° C. The dried material is placed in a catalyst calciner and enters a first temperature rising stage of 7-9 hours, during which the ambient temperature rises from room temperature to 400 ° C; then, enters a second temperature rising stage of 7-9 hours, where During this period, the ambient temperature rose from 400 ° C to 650 ° C; after that, it entered a 7-9 hour cooling phase during which the ambient temperature dropped from 650 ° C to room temperature.

Example 1

In this embodiment, 1000 kg of titanium dioxide is used, and the selected fiber is 80 kg of Rp-chop and glass fiber, wherein the particle size of titanium white powder is d ₁₀ = 0.56 μm, d ₅₀ =1.27 μm, d ₉₀ = 3.64 μm, fiber The diameter R = 7 μm, and the distribution of the fiber length L is 8 kg of 3 mm fiber, 64 kg of 7 mm fiber, and 8 kg of fiber of 20 mm.

Wherein, R=5.51d ₅₀ ; L=5357d ₁₀ , 5511d ₅₀ , 5494d ₉₀ , the weight ratio of the three different length fibers is 1:8:1, and the added mass ratio of the fiber to the titanium dioxide is 0.08:1.

Example 2

In this embodiment, the selected fiber is a total of 90 kg of wood pulp and glass fiber, wherein the particle size of the titanium dioxide is

d ₁₀ =0.67 μm, d ₅₀ =1.12 μm, d ₉₀ =2.37 μm, fiber diameter R=7 μm, and fiber length L distribution: 3.5 mm fiber 22.5 kg, 6.5 mm fiber 45 kg, 12 mm fiber 22.5 kg.

Wherein, R=6.25d ₅₀ , L=5223d ₁₀ , 5803d ₅₀ , 5063d ₉₀ , the weight ratio of the three different length fibers is 1:2:1, and the added mass ratio of fiber to titanium white powder is: 0.09:1, the rest Both are the same as in the first embodiment.

Example 3

In this embodiment, the fiber to be added is selected to be 150 kg of Rp-chop, wood pulp and glass fiber, wherein the particle size of the titanium white powder is d ₁₀ =0.64 μm, d ₅₀ =1.08 μm, d ₉₀ =2.21 μm, diameter of the fiber. R = 7 μm, and the distribution of the fiber length L was: 20 kg of fiber of 3.5 mm, 40 kg of fiber of 6 mm, and 20 kg of fiber of 12 mm.

Wherein, R=6.48d ₅₀ , L=5468d ₁₀ , 5555d ₅₀ , 5429d ₉₀ , the weight ratio of the three different length fibers is 1:2:1, and the added mass ratio of fiber to titanium white powder is: 0.15:1, the rest Both are the same as in the first embodiment.

Example 4

In this embodiment, the fiber to be added is selected to be 80 kg of Rp-chop and glass fiber, wherein the particle size of the titanium white powder is d ₁₀ = 0.56 μm, d ₅₀ =1.27 μm, d ₉₀ = 3.64 μm, and the diameter of the fiber is R=7 μm. The distribution of the fiber length L is 20 kg of 3 mm fiber, 40 kg of 7 mm fiber, and 20 kg of 20 mm fiber.

Wherein, R=5.51d ₅₀ ; L=5357d ₁₀ , 5511d ₅₀ , 5495d ₉₀ , the weight ratio of the three different length fibers is 1:2:1, and the added mass ratio of fiber to titanium white powder is: 0.08:1, the rest Both are the same as in the first embodiment.

Comparative example 1

In the present comparative example, the fiber selected for addition is 80 kg of Rp-chop and glass fiber, wherein the particle size of titanium white powder is d ₁₀ = 0.56 μm, d ₅₀ =1.27 μm, d ₉₀ = 3.64 μm, and the diameter of the fiber is R=7 μm. The fiber length L is 7 mm.

Wherein, R = 5.51d ₅₀ , L = 12500d ₁₀ , 5511d ₅₀ , 1923d ₉₀ , and the added mass ratio of the fiber to the titanium dioxide is 0.08:1, and the rest are the same as in the first embodiment.

Comparative example 2

In the present comparative example, the fiber selected for addition is 80 kg of Rp-chop and glass fiber, wherein the particle size of the titanium white powder is d ₁₀ =0.67 μm, d ₅₀ =1.12 μm, d ₉₀ = 2.37 μm, and the diameter of the fiber R=12 μm. The fiber length L is 7 mm.

Wherein, R = 10.71d ₅₀ , L = 10447d ₁₀ , 6250d ₅₀ , 2953d ₉₀ , and the added mass ratio of the fiber to the titanium dioxide is 0.08:1, and the rest are the same as in the first embodiment.

Comparative example 3

In the present embodiment, the fiber to be added is selected to be 100 kg of Rp-chop and glass fiber, wherein the particle size of the titanium white powder is d ₁₀ = 0.64 μm, d ₅₀ = 1.08 μm, d ₉₀ = 2.21 μm, and the diameter of the fiber is R = 7 μm. The fiber length L is 7 mm.

Wherein, R = 6.48d ₅₀ , L = 10937d ₁₀ , 6481d ₅₀ , 3167d ₉₀ , and the added mass ratio of the fiber to the titanium dioxide is 0.08:1, and the rest are the same as in the first embodiment.

Comparative example 4

In this embodiment, the fiber to be added is selected to be 80 kg of Rp-chop and glass fiber, wherein the particle size of the titanium white powder is d ₁₀ = 0.56 μm, d ₅₀ =1.27 μm, d ₉₀ = 3.64 μm, and the diameter of the fiber is R=7 μm. The fiber length L length is less than 20 mm, and the length is not precisely controlled.

Wherein, R = 5.51d ₅₀ ; the ratio of the added mass of the fiber to the titanium dioxide is 0.08:1, and the rest are the same as in the fourth embodiment.

Comparative example 5

In the present comparative example, the fiber selected for addition is 80 kg of Rp-chop, wood pulp and glass fiber, wherein the particle size of titanium white powder is d ₁₀ =0.68 μm, d ₅₀ =1.15 μm, d ₉₀ = 2.32 μm, diameter of the fiber. R = 7 μm, and the distribution of the fiber length L is: 40 kg of 1 mm fiber, 20 kg of 10 mm fiber, and 20 kg of 20 mm fiber.

Wherein, R=6.09d ₅₀ , L=1470d ₁₀ , 8695d ₅₀ , 8620d ₉₀ , the weight ratio of the fibers of three different lengths is 2:1:1, the ratio of the added mass of fiber to titanium dioxide is: 0.08:1, the rest Both are the same as in the fourth embodiment.

Comparative example 6

In the present comparative example, the fiber selected for addition is 80 kg of Rp-chop, wood pulp and glass fiber, wherein the particle size of titanium white powder is d ₁₀ = 0.58 μm, d ₅₀ =1.15 μm, d ₉₀ = 2.32 μm, diameter of the fiber. R = 1-10 μm (conventional glass fiber, without precise control of the diameter), the distribution of the fiber length L is: 20 mm fiber 20 kg, 6 mm fiber 40 kg, 12 mm fiber 20 kg.

Wherein, R=0.87-8.7d ₅₀ , L=5172d ₁₀ , 5217d ₅₀ , 5172d ₉₀ , the weight ratio of the fibers of three different lengths is 1:2:1, and the mass ratio of fiber to titanium white powder is: 0.08:1 The rest are the same as in the fourth embodiment.

Second, performance testing

The test results of each group of catalyst performance are shown in Table 1.

Table 1 Performance test results of SCR denitration catalysts with different fiber compositions

Serial number name Pass rate Radial compressive strength (MPa) Axial compressive strength (MPa) 1 Comparative example 1 92% 0.87 3.75 2 Comparative example 2 90% 0.83 3.31 3 Comparative example 3 88% 0.51 2.41 4 Comparative example 4 80% 0.42 2.07 5 Comparative example 5 84% 0.49 2.33 6 Comparative example 6 93% 0.92 4.04 7 Example 1 95% 1.02 4.79 8 Example 2 97% 1.18 5.51 9 Example 3 97% 1.26 5.56

10 Example 4 97% 1.24 5.45

Examples 1 to 4 are prepared by adding a fiber according to the distribution of the particle size of titanium dioxide (the relationship between the diameter R of the fiber and the average particle size d ₅₀ of the titanium dioxide is R = 3 to 8 d ₅₀ ; the fiber length L at the diameter R the relationship between the titanium dioxide particle size d is L = 5000 ~ 6000d, the range of d is d ₁₀ ~ d _90; m mass of fibers added at a ratio of the additional mass m _{2. 1} and the titanium dioxide is m _1: m ₂ = 0.06~0.15:1), both the pass rate and the compressive strength have been significantly improved. Among them, in Example 1, since the fiber weight ratio was 1:8:1, the intermediate length of the fiber ratio was too high, resulting in a relatively low compressive strength.

In Comparative Example 1, since the length of the fiber was taken in a single amount, the distribution of the particle size of the titanium dioxide was not satisfied, resulting in a lower yield and compressive strength.

In Comparative Example 2, since the fibers have a diameter 10.71d _50, does not satisfy R = 3 ~ 8d _50; length of the fiber to take a single amount, does not meet the particle size distribution of the titanium dioxide, resulting in lower yields and compressive strength.

In Comparative Example 3, since the length of the fiber was taken in a single amount, the distribution of the particle size of the titanium dioxide was not satisfied, resulting in a lower yield and compressive strength.

In Comparative Example 4, since the length of the fiber was not controlled, the distribution of the particle size of the titanium dioxide was not satisfied, resulting in a lower yield and compressive strength.

In Comparative Example 5, since the fiber length did not satisfy L = 5000 to 6000 d, and the addition ratio of the fiber weight was not appropriate, the yield and the compressive strength were low.

In Comparative Example 6, since the diameter of the fiber was not controlled, the yield and the compressive strength were low.

Only when the fiber reaches a certain distribution density can it function as a skeleton and enhance the strength of the product. Under the same weight, the calculation formula of the number of fibers is:

Let the number of fibers be S, the diameter is R, the length is L, the weight is M, and the density is ρ.

S=M/ρ/(πR ² L/4)

It can be seen that the number of fibers is inversely proportional to the square of the diameter. Therefore, the diameter of the fiber should not be too large, otherwise the number of fibers will be too small to enhance the compressive strength of the product. The invention establishes the relationship between the fiber diameter, the length and the added amount and the particle size of the titanium dioxide. The relationship between the diameter R of the fiber and the average particle size d ₅₀ of the titanium dioxide is R=3～8d ₅₀ ; the fiber length L and the titanium dioxide under the diameter R relationship between particle size d is L = 5000 ~ 6000d, the range of d is d ₁₀ ~ d _90; m mass of fibers added at a ratio of the additional mass m _{2. 1} and the titanium dioxide is _{m 1: m 2 = 0.06 ~} 0.15 :1.

From the above comparison, it can be clearly found that the catalyst for adding fiber according to the particle size distribution of titanium dioxide has a significant improvement in both the pass rate and the compressive strength. The particle size change of the denitrated titanium dioxide is small, so the fiber diameter requirement can be fixed. Different fiber combinations according to the particle size distribution of titanium dioxide can more fully interact with the titanium dioxide particles. On the one hand, the prevention of crack growth improves the product yield rate, and on the other hand, the mechanical strength of the honeycomb catalyst is obviously improved. It has promoted the service life of the catalyst, increased the regeneration rate of the catalyst, and reduced the denitration cost of the power plant.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the embodiments of the present invention. The present invention is not limited to the above-described examples, and equivalent changes and improvements made by those skilled in the art within the scope of the invention are intended to fall within the scope of the invention.

Claims (10)

An SCR honeycomb type denitration catalyst characterized by being made from a raw material comprising the following components: 100 to 150 parts of titanium dioxide, 8 to 20 parts of carboxymethyl cellulose, 5 to 10 parts of polyethylene oxide, 6 to 22.5 parts of fiber, 50 to 80 parts of deionized water, 5 to 15 parts of ammonium metavanadate, and tungsten 10 to 20 parts of ammonium acid, 30 to 55 parts of ammonia water, 10 to 20 parts of lactic acid, 1 to 5 parts of cerium nitrate hexahydrate, and 0.1 to 1.5 parts of cerium nitrate hexahydrate; Wherein, the relationship between the diameter R of the fiber and the average particle size d ₅₀ of the titanium dioxide is R=3 to 8d ₅₀ ; the relationship between the fiber length L at the diameter R and the particle size d of the titanium dioxide is L=5000 to 6000d, and the value of d is in the range of d ₁₀ ~ d _90; additional mass ratio of the additional mass m ₁ and m fiber is titanium dioxide _{2 m 1: m 2 = 0.06 ~} 0.15: 1. The SCR honeycomb type denitration catalyst according to claim 1, wherein the particle size d of the titanium dioxide is normally distributed, and correspondingly, the fiber length L at the diameter R is normally distributed. The SCR honeycomb type denitration catalyst according to claim 1 or 2, wherein the fiber type is Rp-chop, wood pulp, glass fiber, wherein Rp-chop and wood pulp can be mixed or separately added, glass fiber. It must be added to the fiber. A method for preparing an SCR honeycomb type denitration catalyst according to any one of claims 1 to 3, comprising the steps of: (1) Mixing: Including the following small steps: a) dry mixing: 100 to 150 parts of titanium dioxide, 8 to 20 parts of carboxymethyl cellulose and 5 to 10 parts of polyethylene oxide are mixed into a mixer, adding 6 to 22.5 parts of fiber, and mixing; b) Wet mixing: continue to add 50-80 parts of deionized water, 5-15 parts of ammonium metavanadate, 10-20 parts of ammonium metatungstate, 30-55 parts of ammonia water, 10-20 parts of lactic acid, 1-5 parts of nitric acid铈 hexahydrate and 0.1 to 1.5 parts of cerium nitrate hexahydrate, stirred; c) dehumidification: the dehumidification equipment draws out the water vapor in the mixer; (2) Molding: In turn, the following small steps are included: d) filtering the material obtained in the small step c) with a filter plate to leave a material having a particle diameter smaller than the mesh of the filter plate, and preparing the filtered material into a desired shape; e) placing the material of the above shape into an extruder and extruding; (3) Drying: Including the following small steps: f) One drying: it takes 8 to 11 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 30 ° C to 70 ° C, the blowing frequency increases from 15 Hz to 60 Hz, and the air humidity drops from 80% to 10%; g) secondary drying: it takes 14 hours, during which the drying conditions are satisfied: the ambient temperature rises from 35 ° C to 60 ° C; (4) Calcination: Including the following small steps: h) heating stage: it takes 14 to 18 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from room temperature to 650 ° C; i) Cooling phase: It takes 7-9 hours. During this period, the cooling conditions are satisfied: the ambient temperature drops from 650 °C to room temperature. The preparation method according to claim 4, wherein in the small step c), the finally obtained material has a water content of 25% to 30%. The preparation method according to claim 4, wherein in the small step d), the filter plate used is an SCR porous catalyst wet embryo extrusion filter plate: comprising metal strips arranged equidistantly, and further comprising reinforcing ribs. The rib is perpendicular to the metal strip, and the rib is fixed with the metal strip to form a filter plate body. The preparation method according to claim 6, wherein in the small step d), the distance between adjacent metal strips of the filter plate is 0.4 to 0.6 mm. The preparation method according to claim 4, wherein the small step f) comprises the following stages: The first stage: it takes 3-4 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 30 °C to 40 °C, the air supply frequency rises from 15 Hz to 30 Hz, and the air humidity drops from 80% to 70%; The second stage: it takes 3-4 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 40 °C to 60 °C, the air supply frequency increases from 30 Hz to 40 Hz, and the air humidity drops from 70% to 40%; The third stage: it takes 2-3 days. During this period, the drying conditions are satisfied: the ambient temperature rises from 60 ° C to 70 ° C, the supply frequency increases from 40 Hz to 60 Hz, and the air humidity drops from 40% to 10%. The preparation method according to claim 4, wherein in the small step g), the finally obtained material has a water content of 5% to 10%. The preparation method according to claim 4, wherein the small step h) comprises the following stages: The first temperature rising phase: takes 7-9 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from room temperature to 400 ° C; The second temperature rising phase: takes 7-9 hours, during which the temperature rising condition is satisfied: the ambient temperature rises from 400 ° C to 650 ° C.

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