Process for manufacturing high strength shaped refractory bricks

Abstract

The application discloses a manufacturing process of high-strength shaped refractory bricks and relates to the technical field of the refractory bricks. The manufacturing process comprises the following steps: S1, material selection; S2, crushing and mixing; S3, block molding; S4, drying; and S5, baking. The refractory bricks of the design can increase the density and hardness by adding carbon black, fill the gaps of the refractory bricks, improve the wear resistance and corrosion resistance, and have good heat conduction performance, thereby improving the heat conduction efficiency. Meanwhile, the carbon black can stably exist at high temperatures, thereby improving the high-temperature resistance of the refractory material. By increasing the pressure during the pressure forming of the mixed material, the compressive strength of the refractory bricks can be improved. By prolonging the heat preservation time, that is, the heat preservation time in the electric resistance furnace is at least 14 h, the compressive strength and quality of the refractory bricks can be improved under long-time heat preservation.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of firebricks, in particular to a manufacturing process of high-strength shaped firebricks. BACKGROUND

[0002] With the continuous expansion and development of the industrial scale, the application of firebricks is more and more extensive, and the demand is also more and more large. The firebricks are mainly made of fireclay or other refractory raw materials, can withstand high temperature of 1580-1770 DEG C, and can be divided into fired bricks, unfired bricks, electrically fused bricks, refractory heat-insulating bricks and the like according to the preparation process method. The firebricks can be used as high-temperature building materials and structural materials of building kilns and various thermal equipment and can withstand various physical changes and mechanical actions at high temperature.

[0003] A high-strength environment-friendly firebrick and a preparation method thereof are disclosed in a Chinese patent (publication number CN113149668A). The patent has a reasonable formula, uses coke, bauxite, clay, silicon sulfide and elemental silicon as aggregates, uses active alpha-Al2O3 micro powder as an additive, increases the binding force of various components through a binder, and promotes the microporosity of the firebrick through a pore former.

[0004] However, the patent still has some deficiencies. Although the patent uses active alpha-Al2O3 micro powder as an additive to realize the microporosity of the firebrick, the compressive strength is poor in the use process, so that the firebrick is easily affected by the temperature rise and is prone to cracking. In addition, although the patent can realize the microporosity of the firebrick, the thermal conductivity is poor at high temperature, so that the firebrick is prone to cracking and affects the use. Therefore, the technical personnel in the field provide a manufacturing process of high-strength shaped firebricks to solve the problems in the background art. SUMMARY

[0005] The application aims to provide a manufacturing process of high-strength shaped firebricks to solve the problems in the background art.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0007] A manufacturing process of high-strength shaped firebricks, the preparation process of which comprises the following steps:

[0008] S1, material selection: the selected raw materials are composed of 50-60 parts of mineral raw materials, 15-25 parts of carbon black, 20-30 parts of high-alumina bauxite, 15-20 parts of expanded perlite, 5-18 parts of a catalyst, 16-22 parts of refractory fiber, 20-30 parts of a binder and 40-50 parts of deionized water.

[0009] S2, crushing and mixing: the mineral raw material, carbon black, bauxite in S1 are added to the crushing box for crushing and sieving, a 400 mesh screen is used during sieving, after sieving, the mixture is put into the mixing mill for the first mixing treatment, the expanded perlite, catalyst, refractory fiber and binder are added and mixed, and a certain amount of water is added for the second mixing to obtain the mixture;

[0010] S3, block molding: the mixture in S2 is added to the mold and put into the hydraulic testing machine for pressure forming to obtain the blank;

[0011] S4, drying: the blank in S3 is put into the oven for drying treatment;

[0012] S5, calcination: the dried blank is put into the resistance furnace for calcination to obtain high-strength refractory bricks.

[0013] As a further scheme of the application: the mineral raw material in S1 is composed of 30-40 parts of corundum ultrafine powder, 20-30 parts of coke, 20-25 parts of bauxite, 8-12 parts of andalusite, and 5-10 parts of clay.

[0014] As a further scheme of the application: the refractory fiber in S1 is one or more of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber and high-silicon oxygen refractory fiber.

[0015] As a further scheme of the application: the catalyst in S1 is composed of 1-3 parts of boric acid, 1-1.2 parts of manganese oxide, 1.3-1.5 parts of zinc oxide, and 3-5 parts of phenolic resin.

[0016] As a further scheme of the application: the first mixing time in S2 is 20-35 min, the rotating speed is 300-400 r / min, the second mixing time is 30-40 min, and the rotating speed is 250-300 r / min.

[0017] As a further scheme of the application: the pressure forming of the hydraulic testing machine in S3 is divided into two stages, as follows:

[0018] First stage: the hydraulic testing machine initially extrudes the mixture in the mold at 600 KN, and the extrusion time is 1-2 min;

[0019] Second stage: increase the pressure of the hydraulic testing machine, so that the pressure increases from 600 KN to 800 KN, and the extrusion time is 1.5-2 min.

[0020] As a further scheme of the application: the drying in S4 is divided into three stages, as follows:

[0021] First stage: the temperature of the drying oven is heated to 50-70 DEG C, and the drying time is 5-6h to realize the first drying of the blank;

[0022] Second stage: the temperature in the drying oven is heated to 80-100 DEG C for the second drying, and the drying time is 6-8h to realize the second drying of the blank;

[0023] Third stage: the temperature in the drying oven is decreased to 30-40 DEG C, and the drying time is 8-10h to realize the third drying of the blank.

[0024] As a further scheme of the present application, the temperature increasing process in the resistance furnace in S5 is as follows:

[0025] First stage: the temperature in the resistance furnace is heated from normal temperature to 650-900 DEG C, and the holding time is 6-10h;

[0026] Second stage: the temperature in the resistance furnace is heated from 900 DEG C to 1200-1400 DEG C, and the holding time is 8-10h.

[0027] As a further scheme of the present application, after the firing is completed, the temperature in the resistance furnace is decreased to 150-200 DEG C and held for 3-4h.

[0028] The present application provides a manufacturing process of high-strength shaped refractory brick.

[0029] The high-strength shaped refractory brick designed in the present application can increase the density and hardness by adding carbon black, so as to fill the voids of the refractory brick, thereby improving the wear resistance and corrosion resistance, and the carbon black also has good heat conduction performance, thereby improving the heat conduction efficiency, and the carbon black can exist stably at high temperature, thereby improving the high-temperature resistance of the refractory material, the pressure during the pressure forming of the mixture is increased, so as to improve the compressive strength of the refractory brick, and the holding time is prolonged, that is, the holding time in the resistance furnace is at least 14h, so that the long holding time is beneficial to improving the compressive strength and quality of the refractory brick. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0031] The application provides a manufacturing process of high-strength shaped refractory bricks.

[0032] S1, material selection: the selected raw materials are composed of 50-60 parts of mineral raw materials, 15-25 parts of carbon black, 20-30 parts of bauxite, 15-20 parts of expanded perlite, 5-18 parts of catalyst, 16-22 parts of refractory fiber, 20-30 parts of binder and 40-50 parts of deionized water;

[0033] The mineral raw materials in S1 are composed of 30-40 parts of corundum ultrafine powder, 20-30 parts of coke, 20-25 parts of bauxite, 8-12 parts of andalusite and 5-10 parts of clay; the refractory fiber in S1 is one or more of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber and high-silicon oxygen refractory fiber; and the catalyst in S1 is composed of 1-3 parts of boric acid, 1-1.2 parts of manganese oxide, 1.3-1.5 parts of zinc oxide and 3-5 parts of phenolic resin.

[0034] S2, crushing and mixing: the mineral raw materials, carbon black and bauxite in S1 are added to a crushing box for crushing and sieving, a 400-mesh screen is used during sieving, and after sieving, the mixture is put into a mixing mill for first-time mixing, and after mixing, the expanded perlite, catalyst, refractory fiber and binder are added for mixing, and a certain amount of water is added for second-time mixing to obtain a mixture; the first-time mixing time in S2 is 20-35 min, and the rotating speed is 300-400 r / min, and the second-time mixing time is 30-40 min, and the rotating speed is 250-300 r / min.

[0035] S3, mold pressing: the mixture in S2 is added to a mold, and is put into a hydraulic testing machine for pressure forming to obtain a blank;

[0036] In S3, the pressure forming of the hydraulic testing machine is divided into two stages, and the specific process is as follows:

[0037] First stage: the mixture in the mold is extruded by the hydraulic testing machine for the first time at 600KN, and the extrusion time is 1-2 min;

[0038] Second stage: the pressure of the hydraulic testing machine is increased, and the pressure is increased from 600KN to 800KN, and the extrusion time is 1.5-2 min.

[0039] S4, drying: the blank in S3 is put into an oven for drying treatment;

[0040] In S4, the drying is divided into three stages, and the specific process is as follows:

[0041] First stage: the temperature of the drying oven is heated to 50-70 DEG C, and the drying time is 5-6h to realize the first drying of the blank;

[0042] Second stage: the temperature in the drying oven is heated to 80-100 DEG C for the second drying, and the drying time is 6-8h to realize the second drying of the blank;

[0043] Third stage: the temperature in the drying oven is reduced to 30-40 DEG C, and the drying time is 8-10h to realize the third drying of the blank.

[0044] S5, baking: the dried blank is placed into an electric resistance furnace for baking, so that the high-strength refractory brick is obtained;

[0045] The temperature rising process in the electric resistance furnace in S5 is as follows:

[0046] First stage: the temperature in the electric resistance furnace is heated from room temperature to 650-900 DEG C, and the holding time is 6-10h;

[0047] Second stage: the temperature in the electric resistance furnace is heated from 900 DEG C to 1200-1400 DEG C, and the holding time is 8-10h.

[0048] After S5 is completed, the temperature in the electric resistance furnace is reduced to 150-200 DEG C, and the holding time is 3-4h.

[0049] Example one

[0050] In the further technical scheme of the present application, the raw materials for the refractory brick are composed of, by weight fraction: mineral raw material 50 parts, carbon black 15 parts, high alumina bauxite 20 parts, expanded perlite 15 parts, catalyst 5 parts, refractory fiber 16 parts, binder 20 parts, and deionized water 40 parts;

[0051] The mineral raw material is composed of, by weight fraction: corundum ultrafine powder 30 parts, coke 20 parts, bauxite 20 parts, pyrophyllite 8 parts, and clay 5 parts;

[0052] Further, the refractory fiber is one or several of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber, and high-silica refractory fiber;

[0053] The catalyst is composed of, by weight fraction: boric acid 1 part, manganese oxide 1 part, zinc oxide 1.3 parts, and phenolic resin 3 parts.

[0054] Example two

[0055] The raw material of the refractory brick is composed of 55 parts of mineral raw material, 20 parts of carbon black, 25 parts of bauxite, 17 parts of expanded perlite, 12 parts of catalyst, 19 parts of refractory fiber, 25 parts of binder, and 45 parts of deionized water by weight.

[0056] The mineral raw material is composed of 35 parts of corundum ultrafine powder, 25 parts of coke, 22 parts of bauxite, 10 parts of red column, and 7 parts of clay by weight.

[0057] Further, the refractory fiber is one or more of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber, and high-silicon oxygen refractory fiber.

[0058] The catalyst is composed of 2 parts of boric acid, 1.1 parts of manganese oxide, 1.4 parts of zinc oxide, and 4 parts of phenolic resin by weight.

[0059] Example Three

[0060] The raw material of the refractory brick is composed of 60 parts of mineral raw material, 25 parts of carbon black, 30 parts of bauxite, 20 parts of expanded perlite, 18 parts of catalyst, 22 parts of refractory fiber, 30 parts of binder, and 50 parts of deionized water by weight.

[0061] The mineral raw material is composed of 40 parts of corundum ultrafine powder, 30 parts of coke, 25 parts of bauxite, 12 parts of red column, and 10 parts of clay by weight.

[0062] Further, the refractory fiber is one or more of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber, and high-silicon oxygen refractory fiber.

[0063] The catalyst is composed of 3 parts of boric acid, 1.2 parts of manganese oxide, 1.5 parts of zinc oxide, and 5 parts of phenolic resin by weight.

[0064] Experimental Test One: The performance of the refractory brick of the present embodiment is tested, and the test items include bulk density, normal temperature compressive strength, thermal conductivity, and refractory temperature, and the test indexes are shown in the following table:

[0065]

[0066] According to the above indexes, it can be seen that the high-strength shaped refractory brick prepared by the present application has good refractory performance.

[0067] Experimental Test Two: Abrasion test is conducted on the high-strength shaped refractory brick.

[0068] Test Conditions:

[0069] ①Select the firebrick prepared in the embodiments 1-3 of the present application and the clay brick on the market as a comparison for testing, respectively as experimental group one, experimental group two, experimental group three and comparison experimental group one;

[0070] ①Place the firebricks of experimental group one, experimental group two, experimental group three and comparison experimental group one in the state of heating at high temperature 1400 DEG C for 30 days, and record the powdering condition of the firebricks of experimental group one, experimental group two, experimental group three and comparison experimental group one every 10 days, the specific results are shown in the following table:

[0071]

[0072] From the above table, it can be seen that the firebrick designed in the present application compared with the existing clay brick, it will not appear powdering at high temperature, so its wear resistance is higher, and its service life is longer in the long-term use process.

[0073] It should be noted that in this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0074] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, alternatives, and variations can be made in the embodiments without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process for the manufacture of high strength shaped refractory bricks, characterized in that, The preparation process comprises the following steps: S1, selecting materials: the selected raw materials are composed of 50-60 parts of mineral raw materials, 15-25 parts of carbon black, 20-30 parts of high alumina bauxite, 15-20 parts of expanded perlite, 5-18 parts of catalyst, 16-22 parts of refractory fiber, 20-30 parts of binder, and 40-50 parts of deionized water; S2, crushing and mixing: the mineral raw materials, carbon black and high alumina bauxite in S1 are added to the crushing box for crushing and sieving, a 400-mesh screen is used during sieving, and after sieving, the mixture is put into the mixing mill for the first mixing treatment, and the expanded perlite, catalyst, refractory fiber and binder are added for mixing, and a certain amount of water is added for the second mixing to obtain the mixed material; S3, block molding: the mixed material in S2 is added to the mold and put into the hydraulic testing machine for pressure forming to obtain the blank; S4, drying: the blank in S3 is put into the oven for drying treatment; S5, calcination: the dried blank is put into the resistance furnace for calcination to obtain high-strength refractory bricks; The mineral raw materials in S1 are composed of 30-40 parts of corundum ultrafine powder, 20-30 parts of coke, 20-25 parts of bauxite, 8-12 parts of andalusite, and 5-10 parts of clay; The catalyst in S1 is composed of 1-3 parts of boric acid, 1-1.2 parts of manganese oxide, 1.3-1.5 parts of zinc oxide, and 3-5 parts of phenolic resin.

2. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, The refractory fiber in S1 is one or more of zirconia refractory fiber, mullite refractory fiber, aluminum silicate refractory fiber and high-silicon oxygen refractory fiber.

3. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, The first mixing time in S2 is 20-35 min, the rotating speed is 300-400 r / min, the second mixing time is 30-40 min, and the rotating speed is 250-300 r / min.

4. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, The pressure forming of the hydraulic testing machine in S3 is divided into two stages, as follows: First stage: the hydraulic testing machine initially extrudes the mixed material in the mold at 600 KN, and the extrusion time is 1-2 min; Second stage: increase the pressure of the hydraulic testing machine, so that the pressure increases from 600 KN to 800 KN, and the extrusion time is 1.5-2 min.

5. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, The drying in S4 is divided into three stages, as follows: First stage: heat the temperature of the drying box to 50-70℃, and dry the blank for 5-6 h to achieve the first drying; Second stage: heat the temperature in the drying box to 80-100℃ for the second drying, and dry the blank for 6-8 h to achieve the second drying treatment; Third stage: reduce the temperature in the drying box to 30-40℃, and dry the blank for 8-10 h to achieve the third drying treatment.

6. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, The temperature rising process in the resistance furnace in S5 is as follows: First stage: the temperature in the resistance furnace is heated from room temperature to 650-900℃, and the holding time is 6-10 h; Second stage: the temperature in the resistance furnace is heated from 900℃ to 1200-1400℃, and the holding time is 8-10 h.

7. The process for manufacturing high strength shaped refractory bricks as claimed in claim 1 wherein, S5: After the firing is completed, the temperature inside the resistance furnace is reduced to 150-200℃ and kept for 3-4h.

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