A shaped refractory resistant to impact corrosion

Abstract

The application relates to the technical field of refractory materials, and discloses a shaped refractory material with impact corrosion resistance, which comprises the following components by weight: 25-30 parts of kaolin, 10-15 parts of silica sand, 8-12 parts of alumina, 9-14 parts of chromium oxide, 8-10 parts of glass powder, 12-14 parts of graphite, 50-60 parts of water, 6-8 parts of corundum, 4-5 parts of fused mullite, 8-9 parts of silica powder and 10-15 parts of inorganic compound. The silica powder has good chemical corrosion resistance, thereby slowing down the corrosion speed of the refractory brick when the refractory brick is in contact with acid and alkaline medium at high temperature, improving the corrosion resistance, and filling the pores in the refractory material, thereby improving the sintering performance of the brick body, improving the density and strength; the silica sand and the alumina can make the refractory material have excellent high-temperature resistance, acid and alkali corrosion resistance and other performances; the graphite can be used to reduce the friction between the raw materials, improve the density and strength of the refractory material.

Description

Technical Field

[0001] This invention relates to the field of refractory materials technology, specifically a shaped refractory material resistant to impact corrosion. Background Technology

[0002] Refractory materials are generally divided into two types: unshaped refractory materials and shaped refractory materials. Shaped refractory materials generally refer to refractory bricks, which have standard and regular shapes. They can also be temporarily processed during construction as needed. They can also be used as high-temperature building materials and structures for building kilns and various thermal equipment, and can withstand various physical and chemical changes and mechanical actions at high temperatures.

[0003] Chinese patent (publication number CN113233920B) discloses a chlorine-resistant refractory material. The refractory material modified using this patented technology exhibits excellent chlorine corrosion resistance and can be applied to rotary kilns for hazardous waste incineration, solving the problems of insufficient chlorine corrosion resistance and short service life of existing refractory materials for hazardous waste incineration rotary kilns. The modification method of this invention has low requirements for the properties of the refractory material and the molding method, making it widely applicable. Furthermore, the modification method is simple, easy to implement, safe, has a short production cycle, is energy-saving and environmentally friendly, and is easy to promote.

[0004] However, this patent still has shortcomings. Although it solves the problem of chlorine corrosion resistance in refractory materials, its impact resistance is poor during use. This makes the refractory material prone to cracking and becoming unusable under strong external impacts. Therefore, those skilled in the art have provided a shaped refractory material resistant to impact corrosion to solve the problems mentioned in the background art. Summary of the Invention

[0005] The purpose of this invention is to provide a shaped refractory material resistant to impact corrosion, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A shaped refractory material resistant to impact corrosion, the shaped refractory material comprising the following raw materials in parts by weight: 25-30 parts kaolin, 10-15 parts silica sand, 8-12 parts alumina, 9-14 parts chromium oxide, 8-10 parts glass powder, 12-14 parts graphite, 50-60 parts water, 6-8 parts corundum, 4-5 parts fused mullite, 8-9 parts silica powder, and 10-15 parts inorganic compound, wherein the inorganic compound is chromium trioxide.

[0008] As a further embodiment of the present invention: the shaped refractory material comprises the following raw materials in parts by weight: 25 parts kaolin, 10 parts silica sand, 8 parts alumina, 9 parts chromium oxide, 8 parts glass powder, 12 parts graphite, 50 parts water, 6 parts corundum, 4 parts fused mullite, 8 parts silica powder, and 10 parts inorganic compound, wherein the inorganic compound is chromium trioxide.

[0009] As a further embodiment of the present invention: the shaped refractory material comprises the following raw materials in parts by weight: 28 parts kaolin, 12 parts silica sand, 10 parts alumina, 11 parts chromium oxide, 9 parts glass powder, 13 parts graphite, 55 parts water, 7 parts corundum, 4 parts fused mullite, 8 parts silica powder, and 12 parts inorganic compound, wherein the inorganic compound is chromium trioxide.

[0010] As a further embodiment of the present invention: the shaped refractory material comprises the following raw materials in parts by weight: 30 parts kaolin, 15 parts silica sand, 10 parts alumina, 14 parts chromium oxide, 10 parts glass powder, 14 parts graphite, 60 parts water, 8 parts corundum, 5 parts fused mullite, 9 parts silica powder, and 15 parts inorganic compound, wherein the inorganic compound is chromium trioxide.

[0011] As a further embodiment of the present invention: the average particle diameter of the electrofused mullite is 0.1-2 mm, and the average particle diameter of the kaolin is 0.2-0.5 mm.

[0012] As a further aspect of the present invention: the method for preparing the refractory material includes the following steps:

[0013] S1. Material preparation: First, prepare the raw materials for refractory materials. These raw materials are screened, ground and mixed to achieve the required physical state.

[0014] S2. Preparation of brick blanks: Add water to the mixed refractory material and stir to obtain a slurry-like mixture. Then pour the mixture into a mold, compact it, and remove it to dry.

[0015] S3. Firing: The brick blanks are placed in a kiln for high-temperature firing for more than 10 hours.

[0016] S4. Trimming: After firing, the bricks are trimmed and cut to obtain refractory brick materials of the required size and shape.

[0017] As a further aspect of the present invention: the stirring in step S2 is carried out in two stages, as detailed below.

[0018] First stage: Use a stirring motor with a speed of 300-350 r / min and a stirring time of 20-30 min;

[0019] First stage: Use a stirring motor with a speed of 200-250 r / min and a stirring time of 15-20 min.

[0020] As a further aspect of the present invention: the mixture in S2 undergoes two stages during pressure testing, as detailed below.

[0021] First stage: The hydraulic testing machine extrudes the mixture in the mold at 700KN for 1-1.5 minutes;

[0022] The second stage: Increase the pressure of the hydraulic testing machine from 700KN to 900KN, and the extrusion time is 1.5-2 minutes.

[0023] As a further aspect of the present invention: the firing process in S3 is divided into three stages:

[0024] First stage: The temperature inside the kiln is raised from room temperature to 650-800℃, and the holding time is 5-8 hours;

[0025] The second stage: the temperature inside the kiln is raised from 800℃ to 1400-1600℃, and the holding time is 6-10 hours;

[0026] The third stage: the temperature inside the kiln drops from 1600℃ to 300-500℃, and the holding time is 3-4 hours.

[0027] The impact-corrosion resistant refractory material designed in this invention has the following advantages compared with the prior art:

[0028] The impact-corrosion resistant shaped refractory material designed in this invention incorporates silica powder, which combines with high-alumina materials to form a composite material with good refractory properties. This improves the refractory material's refractory temperature, thermal conductivity, and thermal shock resistance. Furthermore, silica powder exhibits good resistance to chemical corrosion, slowing down the corrosion rate of refractory bricks when in contact with acidic or alkaline media at high temperatures, thus enhancing its corrosion resistance. Simultaneously, silica powder fills the pores within the refractory material, improving the sintering performance of the bricks and increasing density and strength. The addition of silica sand and alumina gives the refractory material excellent high-temperature resistance and acid / alkali corrosion resistance. Graphite reduces friction between raw materials, increasing the density and strength of the refractory material. The addition of glass powder, corundum, and fused mullite improves the strength of the refractory material, resulting in good impact resistance and thus extending its service life. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] This invention provides a technical solution for a shaped refractory material resistant to impact corrosion: the shaped refractory material comprises the following raw materials in parts by weight: 25-30 parts kaolin, 10-15 parts silica sand, 8-12 parts alumina, 9-14 parts chromium oxide, 8-10 parts glass powder, 12-14 parts graphite, 50-60 parts water, 6-8 parts corundum, 4-5 parts fused mullite, 8-9 parts silica powder, and 10-15 parts inorganic compound, wherein the inorganic compound is chromium trioxide.

[0031] Example 1

[0032] The shaped refractory material comprises the following raw materials in parts by weight: 25 parts kaolin, 10 parts silica sand, 8 parts alumina, 9 parts chromium oxide, 8 parts glass powder, 12 parts graphite, 50 parts water, 6 parts corundum, 4 parts fused mullite, 8 parts silica powder, and 10 parts inorganic compound, the inorganic compound being chromium trioxide.

[0033] Among them, the average particle diameter of electrofused mullite is 0.1-2 mm, and the average particle diameter of kaolin is 0.2-0.5 mm.

[0034] Example 2

[0035] The shaped refractory material comprises the following raw materials in parts by weight: 28 parts kaolin, 12 parts silica sand, 10 parts alumina, 11 parts chromium oxide, 9 parts glass powder, 13 parts graphite, 55 parts water, 7 parts corundum, 4 parts fused mullite, 8 parts silica powder, and 12 parts inorganic compound, the inorganic compound being chromium trioxide.

[0036] Among them, the average particle diameter of electrofused mullite is 0.1-2 mm, and the average particle diameter of kaolin is 0.2-0.5 mm.

[0037] Example 3

[0038] The shaped refractory material comprises the following raw materials in parts by weight: 30 parts kaolin, 15 parts silica sand, 10 parts alumina, 14 parts chromium oxide, 10 parts glass powder, 14 parts graphite, 60 parts water, 8 parts corundum, 5 parts fused mullite, 9 parts silica powder, and 15 parts inorganic compound, the inorganic compound being chromium trioxide.

[0039] Among them, the average particle diameter of electrofused mullite is 0.1-2 mm, and the average particle diameter of kaolin is 0.2-0.5 mm.

[0040] The preparation method of refractory materials includes the following steps:

[0041] S1. Material preparation: First, prepare the raw materials for refractory materials. These raw materials are screened, ground and mixed to achieve the required physical state.

[0042] S2. Preparation of brick blanks: Add water to the mixed refractory material and stir to obtain a slurry-like mixture. Then pour the mixture into a mold, compact it, and remove it to dry.

[0043] The stirring process in S2 employs two stages, as detailed below.

[0044] First stage: Use a stirring motor with a speed of 300-350 r / min and a stirring time of 20-30 min;

[0045] First stage: Use a stirring motor with a speed of 200-250 r / min and a stirring time of 15-20 min.

[0046] The mixture in S2 undergoes two stages during pressure testing, as detailed below.

[0047] First stage: The hydraulic testing machine extrudes the mixture in the mold at 700KN for 1-1.5 minutes;

[0048] The second stage: Increase the pressure of the hydraulic testing machine from 700KN to 900KN, and the extrusion time is 1.5-2 minutes.

[0049] S3. Firing: The brick blanks are placed in a kiln for high-temperature firing for at least 10 hours; S3 firing is divided into three stages:

[0050] First stage: The temperature inside the kiln is raised from room temperature to 650-800℃, and the holding time is 5-8 hours;

[0051] The second stage: the temperature inside the kiln is raised from 800℃ to 1400-1600℃, and the holding time is 6-10 hours;

[0052] The third stage: the temperature inside the kiln drops from 1600℃ to 300-500℃, and the holding time is 3-4 hours.

[0053] S4. Trimming: After firing, the bricks are trimmed and cut to obtain refractory brick materials of the required size and shape.

[0054] Experimental testing: Performance tests were conducted on the refractory bricks of this embodiment. The test items included bulk density, room temperature compressive strength, thermal shock stability, refractoriness temperature, and apparent porosity. The test indicators are shown in the table below:

[0055]

[0056] As can be seen from the above indicators, the refractory material prepared by this invention has a smaller apparent porosity, more stable thermal shock resistance, superior refractory performance, and good impact resistance, thereby improving the service life of the refractory material.

[0057] Experimental Test 2: Corrosion Resistance Test of Refractory Materials

[0058] Test conditions: ① Select two or more corrosion solutions, designated as corrosion solution No. 1 and corrosion solution No. 2, and compare the refractory materials prepared in Examples 1-3 of this invention with existing refractory materials on the market for testing, respectively designated as experimental group 1, experimental group 2, experimental group 3 and comparative experimental group 1;

[0059] ② Experimental groups 1, 2, and 3, as well as control group 1, were placed inside the corrosive solution at the same height. The corrosion status of experimental groups 1, 2, and 3, as well as control group 1, was recorded periodically. The specific results are shown in the table below:

[0060]

[0061] As can be seen from the table above, the refractory material designed in this invention has stronger corrosion resistance and a longer service life compared to existing refractory materials.

[0062] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0063] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A shaped refractory resistant to impact corrosion, characterized in that, The shaped refractory material comprises the following components by weight: 25-30 parts of kaolin, 10-15 parts of silica sand, 8-12 parts of alumina, 9-14 parts of chromium oxide, 8-10 parts of glass powder, 12-14 parts of graphite, 50-60 parts of water, 6-8 parts of corundum, 4-5 parts of fused mullite, 8-9 parts of silica powder, and 10-15 parts of inorganic compound, which is dichromic trioxide; The preparation method of the refractory material comprises the following steps: S1, material preparation: first, prepare the raw materials of the refractory material, and screen, grind and mix the raw materials to achieve the required physical state; S2, preparation of green bricks: mix the mixed refractory material with water to obtain a slurry-like mixture, then pour the mixture into a mold and compact it to form a green brick, and then take it out and dry it; S3, firing: put the green brick into a kiln for high-temperature firing, and the firing time is more than 10 hours; S4, trimming: after firing, trim and cut the brick to obtain refractory bricks of the required size and shape; The firing in S3 is divided into three stages: First stage: the temperature in the kiln is heated from room temperature to 650-800℃, and the holding time is 5-8 hours; Second stage: the temperature in the kiln is heated from 800℃ to 1400-1600℃, and the holding time is 6-10 hours; Third stage: the temperature in the kiln is reduced from 1600 to 300-500℃, and the holding time is 3-4 hours.

2. A shaped refractory resistant to impact corrosion according to claim 1, characterized in that, The shaped refractory material comprises the following components by weight: 25-30 parts of kaolin, 10-15 parts of silica sand, 8-12 parts of alumina, 9-14 parts of chromium oxide, 8-10 parts of glass powder, 12-14 parts of graphite, 50-60 parts of water, 6-8 parts of corundum, 4-5 parts of fused mullite, 8-9 parts of silica powder, and 10-15 parts of inorganic compound, which is dichromic trioxide.

3. A shaped refractory material resistant to impact corrosion according to claim 1, characterized in that, The shaped refractory material comprises the following components by weight: 25-30 parts of kaolin, 10-15 parts of silica sand, 8-12 parts of alumina, 9-14 parts of chromium oxide, 8-10 parts of glass powder, 12-14 parts of graphite, 50-60 parts of water, 6-8 parts of corundum, 4-5 parts of fused mullite, 8-9 parts of silica powder, and 10-15 parts of inorganic compound, which is dichromic trioxide.

4. A shaped refractory material resistant to impact corrosion according to claim 1, characterized in that, The shaped refractory material comprises the following components by weight: 25-30 parts of kaolin, 10-15 parts of silica sand, 8-12 parts of alumina, 9-14 parts of chromium oxide, 8-10 parts of glass powder, 12-14 parts of graphite, 50-60 parts of water, 6-8 parts of corundum, 4-5 parts of fused mullite, 8-9 parts of silica powder, and 10-15 parts of inorganic compound, which is dichromic trioxide.

5. A shaped refractory material resistant to erosion corrosion according to claim 1, characterized in that, The average particle diameter of the fused mullite is 0.1-2mm, and the average particle diameter of the kaolin is 0.2-0.5mm.

6. A shaped refractory material resistant to erosion corrosion according to claim 1, characterized in that, The stirring in S2 adopts two stages, specifically as follows, First stage: use a stirring motor with a speed of 300-350r / min, and the stirring time is 20-30 minutes; Second stage: use a stirring motor with a speed of 200-250r / min, and the stirring time is 15-20 minutes.

7. A shaped refractory material resistant to erosion corrosion according to claim 1, characterized in that, The mixture in S2 adopts two stages when compacting, specifically as follows, First stage: the hydraulic press machine extrudes the mixture in the mold at 700KN, and the extrusion time is 1-1.5min; Second stage: increase the pressure of the hydraulic press machine, so that the pressure increases from 700KN to 900KN, and the extrusion time is 1.5-2min.

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