High-strength ceramic tile based on pulverized coal cinder and red mud and preparation method of high-strength ceramic tile

Abstract

The invention provides a high-strength ceramic tile based on powdered coal cinder and red mud and a preparation method of the high-strength ceramic tile, and a ceramic green body of the high-strength ceramic tile is prepared from the following raw materials in percentage by mass: 40-70% of red mud, 10-30% of powdered coal cinder, 8-15% of sodium stone powder, 8-15% of potassium sand, 0-12% of clay and 0-6% of magnesium soil. According to the embodiment of the invention, a large amount of red mud and powdery coal slag can be reasonably utilized, resources are saved for ceramic production, the firing temperature can be reduced, meanwhile, the content of crystal phases in the ceramic is greatly increased and is richer, and the strength, toughness and wear resistance of the ceramic tile are improved.

Description

Technical Field

[0001] The present invention relates to the field of ceramic technology, in particular to a high-strength ceramic brick based on fly ash and red mud and a preparation method thereof. Background Art

[0002] With the rapid development of industrial production, the types and quantities of industrial solid waste are increasing, which not only pollutes the environment but also causes serious waste of resources. At the same time, the problem of waste disposal also brings invisible pressure to enterprises.

[0003] Red mud is a solid waste generated during the production of alumina from bauxite, resulting in significant amounts of waste. Its high alkalinity, fine particle size, and complex composition make its comprehensive utilization challenging. Furthermore, industry, power plants, civilian boilers, and other coal-fired equipment generate large quantities of coal slag. The accumulation of abandoned slag occupies land, and long-term storage can burden the ecological environment. Directly treating this industrial waste is costly.

[0004] Therefore, the existing technology has defects and needs to be improved and developed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a high-strength ceramic brick based on pulverized coal slag and red mud and a preparation method thereof in response to the above-mentioned defects of the prior art, aiming to solve the problem that red mud and slag are not reasonably utilized in the prior art.

[0006] The technical solutions adopted by the present invention to solve the technical problems are as follows:

[0007] In a first aspect, an embodiment of the present application provides a high-strength ceramic brick based on fly ash and red mud, wherein the raw materials used in the ceramic body of the high-strength ceramic brick include, by mass percentage:

[0008] Red mud 40-70%, pulverized coal slag 10-30%, sodium stone powder 8-15%, potassium sand 8-15%, clay 0-12%, magnesia soil 0-6%.

[0009] According to the above-mentioned technical means, the embodiments of the present application save resources for ceramic production by rationally utilizing a large amount of red mud and pulverized coal slag, and can reduce the firing temperature. At the same time, the crystal phase content in the ceramics is greatly increased and richer, thereby improving the strength, toughness and wear resistance of the ceramic tiles.

[0010] In one embodiment of the present application, the chemical components of the ceramic body of the high-strength ceramic tile, calculated by mass percentage, include:

[0011] SiO2 32.1~40.6%, Al2O3 19.5~26.5%, CaO 2.30~4.25%, MgO0.40~2.93%, K2O 0.78~1.13%, Na2O 3.32~4.69%, Fe2O3 20.57~27.94%, TiO2 2.02~3.48%, loss on ignition 5.92~8.76%.

[0012] According to the above technical means, the ceramic body of the embodiment of the present application has a very high iron oxide content, so that the firing temperature of the ceramic body is relatively low.

[0013] In one embodiment of the present application, the modulus of rupture of the ceramic body of the high-strength ceramic tile is 4 to 6 MPa.

[0014] According to the above-mentioned technical means, red mud is added to the raw material formula of the ceramic green body in the embodiment of the present application. Since the red mud particles are fine and have a large specific surface area, the van der Waals force and capillary force between the particles are strong after drying, so that the rupture modulus of the ceramic green body reaches 4 to 6 MPa, thereby improving the strength of the ceramic green body.

[0015] In one embodiment of the present application, the chemical components of the red mud, calculated by mass percentage, include:

[0016] SiO2 16~25%, Al2O3 19~25%, CaO 4~7%, MgO 0~1.5%, K2O0.5~1.5%, Na2O4~7%, Fe2O3 30~36%, TiO2 3~5%, loss on ignition 8~10%.

[0017] According to the above-mentioned technical means, Fe2O3 and alkali metal oxides (Na2O, K2O) in the red mud of the embodiment of the present application form a low eutectic liquid phase at high temperature, which significantly reduces the firing temperature and reduces energy consumption; CaO reacts with SiO2 / Al2O3 to form calcium feldspar, further promoting densification; Al2O3 and Fe2O3 generate crystals during sintering, which can improve the hardness and flexural strength of the green body, thereby improving the strength of the ceramic green body and reducing the firing temperature.

[0018] In one embodiment of the present application, the chemical components of the fly ash, calculated by mass percentage, include:

[0019] Loss on ignition 0.25%~1.16%, Al2O3 25%~35%, SiO2 45.35~58.88%, Fe2O34.65~5.97%, CaO 4.05~6.71%, MgO 0.25~1.55%, K2O 0.1~1.55%, Na2O0.15~1.01%.

[0020] According to the above technical means, the embodiment of the present application reduces the firing temperature of ceramic production by adding pulverized coal slag, thereby achieving low-temperature fast firing and reducing the cost of ceramic production.

[0021] In one embodiment of the present application, the clay includes ball clay, kaolin and / or bentonite.

[0022] According to the above technical means, the embodiments of the present application do not limit the specific raw materials of clay, and low-priced clay can be selected according to local conditions. Moreover, when a single clay source is in short supply, it can be quickly replaced with other clays to ensure production continuity, thereby improving the production efficiency and production cost of ceramic tiles.

[0023] A second embodiment of the present application provides a method for preparing the high-strength ceramic brick based on fly ash and red mud as described above, which comprises:

[0024] Mixing 40-70% of red mud, 10-30% of pulverized coal slag, 8-15% of sodium stone powder, 8-15% of potassium sand, 0-12% of clay, and 0-6% of magnesia soil by mass to obtain a mixed raw material;

[0025] The mixed raw materials are ball-milled, powdered, aged, pressed into shape, and dried to obtain a ceramic body;

[0026] The ceramic body is glazed, decorated with printing, and coated with brick base slurry, and then fired in a kiln to produce high-strength ceramic tiles.

[0027] According to the above technical means, the embodiment of the present application uses a large amount of red mud and pulverized coal slag to produce high-strength ceramic tiles with diverse decorative effects, improves the utilization rate of industrial tailings, improves resource utilization efficiency while reducing the firing temperature, and achieves cost reduction and efficiency improvement.

[0028] In one embodiment of the present application, the mixed raw materials are ball-milled, powdered, aged, pressed and dried to obtain a ceramic body, comprising:

[0029] After adding water and water reducing agent to the mixed raw materials, the mixed raw materials are fed into a ball mill and milled into a slurry with a 325 mesh sieve residue of 0.6-1.5%;

[0030] The slurry is spray-dried to obtain a powder, wherein the moisture content of the powder is 6.5-7.5%;

[0031] Pressing and molding the powder after aging to obtain a molded body;

[0032] The formed green body is sent to a drying kiln for drying to obtain a ceramic green body with a moisture content of less than 0.5%. The temperature of the ceramic green body when it leaves the drying kiln is 120-150°C.

[0033] According to the above technical means, by controlling the ball milling fineness, controlling the moisture content of the powder, and drying in a drying kiln, a ceramic green body with moisture content less than 0.5% is obtained, thereby obtaining a ceramic green body with high strength and few defects.

[0034] In one embodiment of the present application, the water reducing agent is water glass, sodium humate, sodium tripolyphosphate or sodium hexametaphosphate.

[0035] According to the above technical means, the embodiments of the present application can adopt different water reducers to improve applicability, optimize particle arrangement through the water reducer, improve the flexural strength after drying, and reduce uneven sintering caused by agglomeration.

[0036] In one embodiment of the present application, firing in a kiln includes:

[0037] It is fired in an oxidizing atmosphere in a roller kiln with a firing temperature of 1120-1145°C and a firing cycle of 38-42 minutes.

[0038] According to the above technical means, the embodiment of the present application reduces the firing temperature, shortens the firing cycle, realizes low-temperature and fast firing of ceramic tiles, and saves the cost of ceramic production.

[0039] The present invention achieves the following beneficial effects:

[0040] First, the embodiments of the present application can reasonably utilize a large amount of red mud and pulverized coal slag, saving resources for ceramic production and reducing the firing temperature. At the same time, the crystalline phase content in the ceramic is greatly increased and richer, thereby improving the strength, toughness and wear resistance of the ceramic tiles.

[0041] Second, the embodiments of the present application greatly improve the utilization rate of industrial tailings, effectively reduce the harm caused by long-term accumulation of industrial tailings to land and groundwater, and also save huge costs for the production of building ceramics. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a preferred embodiment of a method for preparing high-strength ceramic bricks based on pulverized coal slag and red mud in the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clear and distinct, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] With the rapid development of the ceramic industry, ceramic mineral resources are being consumed and wasted in significant quantities. This has resulted in the depletion of many high-quality ceramic raw materials, and their high prices have also limited their application. Therefore, the reuse of industrial solid waste has received considerable attention. The vigorous development and utilization of low-quality raw materials and industrial waste not only helps preserve high-quality ceramic raw materials, but also reduces production costs, improves the economic benefits of enterprises, and contributes to the sustainable development of the ceramic industry.

[0045] Compared to other industrial waste residues, the utilization rate and level of fly ash are relatively low. This is because coal ash is primarily used in concrete, foamed ceramics, and roadbeds. When used in ceramics, the carbides in the ash easily generate gas during high-temperature firing, and the high iron content affects the color of the ceramic body. This significantly limits the scope and quantity of fly ash applications, contributing to the low utilization rate.

[0046] The embodiment of the present application adjusts the formula to prepare a building ceramic product with a high dosage of industrial tailings and high strength, while having little impact on the existing production process and can be used on a large scale in the building ceramic industry.

[0047] The embodiments of the present application can solve the following problems:

[0048] First, it solves the problem of adding high-iron red mud into ceramic formulas, with the addition amount being 40-70%, completely overturning the existing ceramic production technology;

[0049] Second, it solves the problem of adding pulverized coal slag into ceramic formulas, with the addition amount being 10-30%, which greatly improves the utilization rate of pulverized coal slag in the ceramic industry;

[0050] Third, by adding high amounts of different industrial tailings to the ceramic body, the physical phase of the ceramic body is made richer, thereby achieving the effect of improving strength;

[0051] Fourth, the high content of industrial tailings makes the firing temperature of ceramic products significantly lower than that of conventional silicon-aluminum formula, which has a wider adaptability, facilitates production, saves costs and reduces energy consumption;

[0052] Fifth, it solves the problem of bricks used in conventional ancient buildings. No additional colorants are needed, and the product has high strength. Tiles of different thicknesses can be prepared by extrusion molding according to needs. The strength is significantly higher than that of ordinary ceramic tiles, and there is a sound of metal and stone when knocked;

[0053] Sixth, it solves the problem of long-term accumulation of industrial waste residues, especially the problem of heavy metals in industrial waste residues easily mixing into groundwater sources, occupying and polluting land and water sources;

[0054] Seventh, it solves the problem of resource utilization of industrial waste residues, transforming industrial waste residues from waste into resource materials.

[0055] The present invention provides a high-strength ceramic brick based on fly ash and red mud. The raw materials used in the ceramic body of the high-strength ceramic brick include, by mass percentage:

[0056] Red mud 40-70%, pulverized coal slag 10-30%, sodium stone powder 8-15%, potassium sand 8-15%, clay 0-12%, magnesia soil 0-6%.

[0057] Specifically, red mud contains high levels of iron oxide, calcium oxide, sodium oxide, and titanium oxide. Therefore, red mud has a relatively low firing temperature, making it suitable for low-temperature firing. Fly coal slag, a byproduct of coal pulverization, has a high aluminum oxide content and also contains a certain amount of iron oxide. Combined with the high iron content of red mud, this gives the ceramic green body of this application a high iron oxide content, allowing it to be fired at a lower temperature than green bodies with conventional silicon-aluminum formulations.

[0058] The main mineral of sodium stone powder is albite, and its key components include: Na2O, Al2O3, and SiO2, which are used to provide sodium ions to promote the formation of the glass phase and enhance the glaze gloss. The main mineral of Ming potash sand is potassium feldspar, and its key components include: K2O, Al2O3, and SiO2, which are used to provide potassium ions, promote the formation of mullite, and enhance strength. Before drying, the binding force of clay enables the green body to maintain its shape and prevent cracking or deformation. In addition, clay melts at high temperature to form a liquid phase, filling the gaps between particles and promoting sintering and densification of the green body. The binding force between clay particles gives the green body its initial strength after drying; the mullite crystals formed at high temperature enhance the mechanical strength after firing. Magnesia clay can reduce the thermal expansion coefficient, promote sintering, and reduce the firing temperature.

[0059] The embodiments of the present application can reasonably utilize a large amount of red mud and pulverized coal slag, save resources for ceramic production, and can reduce the firing temperature. At the same time, the crystalline phase content in the ceramic is greatly increased and richer, thereby improving the strength, toughness and wear resistance of the ceramic tiles.

[0060] In the embodiment of the present application, the chemical components of the ceramic body of the high-strength ceramic tile, calculated by mass percentage, include:

[0061] SiO2 32.1~40.6%, Al2O3 19.5~26.5%, CaO 2.30~4.25%, MgO0.40~2.93%, K2O 0.78~1.13%, Na2O 3.32~4.69%, Fe2O3 20.57~27.94%, TiO2 2.02~3.48%, loss on ignition 5.92~8.76%.

[0062] Specifically, SiO2 forms a glassy matrix, reacting with Fe2O3 and Al2O3 to form mullite, improving thermal stability and structural density. Al2O3 increases the mullite phase, inhibiting excessive vitrification and reducing high-temperature deformation. CaO and MgO form a low-temperature eutectic with Fe2O3, accelerating sintering and reducing porosity. K2O and Na2O act as fluxes, reducing melt viscosity, promoting uniform liquid phase distribution, and improving surface smoothness. TiO2 forms a solid solution with Fe2O3, enhancing color stability and reducing color variation after firing.

[0063] The ceramic body of the embodiment of the present application has a very high iron oxide content, which results in a relatively low firing temperature for the ceramic body.

[0064] In one embodiment of the present application, the high-strength ceramic tile has a ceramic body with a modulus of rupture of 4-6 MPa. Specifically, although red mud is a residual slag after extraction, its fine particles provide good strength for the body. A single body can have a modulus of rupture of 4-6 MPa, sufficient to provide basic support for the ceramic body.

[0065] Red mud is added to the raw material formula of the ceramic green body in the embodiment of the present application. Since the red mud particles are fine and have a large specific surface area, the van der Waals force and capillary force between the particles are strong after drying, so that the modulus of rupture of the ceramic green body reaches 4 to 6 MPa, while the modulus of rupture of ordinary ceramic green bodies usually does not exceed 2 MPa. Therefore, the present application greatly improves the strength of the ceramic green body.

[0066] In the embodiment of the present application, the chemical components of the red mud, calculated by mass percentage, include:

[0067] SiO2 16~25%, Al2O3 19~25%, CaO 4~7%, MgO 0~1.5%, K2O0.5~1.5%, Na2O4~7%, Fe2O3 30~36%, TiO2 3~5%, loss on ignition 8~10%.

[0068] Specifically, Fe2O3 and alkali metal oxides (Na2O, K2O) in the red mud of the embodiment of the present application form a low eutectic liquid phase at high temperature, which significantly reduces the firing temperature and reduces energy consumption; CaO reacts with SiO2 / Al2O3 to form anorthite, further promoting densification; Al2O3 and Fe2O3 generate crystals during sintering, which can improve the hardness and flexural strength of the green body, thereby improving the strength of the ceramic green body and reducing the firing temperature.

[0069] The embodiment of the present application improves the strength of the ceramic body and reduces the firing temperature by adding red mud.

[0070] In the embodiment of the present application, the chemical components of the fly ash, calculated by mass percentage, include:

[0071] Loss on ignition 0.25%~1.16%, Al2O3 25%~35%, SiO2 45.35~58.88%, Fe2O34.65~5.97%, CaO 4.05~6.71%, MgO 0.25~1.55%, K2O 0.1~1.55%, Na2O0.15~1.01%.

[0072] Specifically, fly slag is rich in Al2O3, CaO, and Fe2O3, with Al2O3 content reaching approximately 30%. Ball clay and kaolin can achieve this content, but the procurement cost is high. Raw materials with high Al2O3 content are in short supply on the market, are mostly synthetic, and are relatively expensive. For ceramic raw materials, Al2O3 forms the ceramic product skeleton with SiO2 at high temperatures and is also a key component in the formation of mullite reinforcement. CaO, with a content of approximately 5%, is an excellent mineralizer in ceramic raw materials, reducing the firing temperature during ceramic production and playing a key role in achieving low-temperature, fast firing.

[0073] The embodiment of the present application reduces the firing temperature of ceramic production by adding pulverized coal slag, thereby achieving low-temperature fast firing and reducing the cost of ceramic production.

[0074] In one embodiment of the present application, the clay includes ball clay, kaolin and / or bentonite.

[0075] Specifically, ball clay has extremely fine particles and strong plasticity, which can improve green body strength and promote sintering. Kaolin, with its high chemical stability, high whiteness, and low shrinkage, provides Al2O3 and forms mullite at high temperatures, enhancing the body's refractoriness and mechanical strength. Its low shrinkage can also reduce cracking during firing. Bentonite, primarily montmorillonite, is highly absorbent, and even a small addition can significantly improve green body plasticity.

[0076] The embodiments of the present application do not limit the specific raw materials of clay. Low-cost clay can be selected according to local conditions. Moreover, when a single clay source is in short supply, it can be quickly replaced with other clays to ensure production continuity, thereby improving the production efficiency and production cost of ceramic tiles.

[0077] In one embodiment, the chemical composition of the sodium stone powder, calculated by mass percentage, includes: SiO2 73-78%, Al2O3 13-16%, Fe2O3 0-0.6%, CaO 0-1%, MgO 0-1%, K2O 1-2%, Na2O 4-6%, and loss on ignition 1-2%; the chemical composition of the potash sand, calculated by mass percentage, includes: SiO2 66-75%, Al2O3 16-20%, Fe2O3 1.2-2.6%, CaO 0-1%, MgO 0-1%, K2O 4-7%, Na2O 0-1.5%, and loss on ignition 3-5%; the chemical composition of the clay, calculated by mass percentage, includes: SiO2 56-64%, Al2O3 22-28%, Fe2O3 0.5-2%, CaO 0-1%, MgO 0-1%, K2O 1.5-3%, Na2O 0-1.5%, and loss on ignition 7-9%; the chemical composition of the magnesia soil, calculated by mass percentage, includes: SiO2 58-65%, Al2O3 2-6%, Fe2O3 0.5-2%, CaO 0-1%, MgO 21-27%, K2O 0-1%, Na2O 0-1%, and loss on ignition 4-7%.

[0078] like Figure 1 As shown, the present application also provides a method for preparing the high-strength ceramic brick based on fly ash and red mud as described above, comprising:

[0079] Step S100, mixing 40-70% of red mud, 10-30% of pulverized coal slag, 8-15% of sodium stone powder, 8-15% of potassium sand, 0-12% of clay, and 0-6% of magnesia soil, by mass percentage, to obtain a mixed raw material;

[0080] Step S200, ball-milling, powdering, aging, pressing and drying the mixed raw materials to obtain a ceramic body;

[0081] Step S300: Glaze, print and decorate the ceramic body, apply base slurry to the body, and then put it into a kiln for firing to obtain a high-strength ceramic tile.

[0082] Specifically, ball milling the mixed raw materials ensures uniform particle size, while aging eliminates internal stress, reduces the risk of cracking during compaction, and improves product yield. Furthermore, the high-strength ceramic tiles of the present invention can be glazed and printed for diverse decorative effects. Applying a base slurry to the tiles reduces stress on the glaze during firing, preventing later cracking.

[0083] The embodiments of the present application use a large amount of red mud and pulverized coal slag to produce high-strength ceramic tiles with diverse decorative effects, improve the utilization rate of industrial tailings, improve resource utilization efficiency while reducing the firing temperature, and achieve cost reduction and efficiency improvement.

[0084] In the embodiment of the present application, step S200 specifically includes:

[0085] Step S210: After adding water and a water reducing agent to the mixed raw materials, the mixed raw materials are fed into a ball mill and milled into a slurry with a 325 mesh sieve residue of 0.6-1.5%;

[0086] Step S220: spray-drying the slurry to obtain a powder, wherein the moisture content of the powder is 6.5-7.5%;

[0087] Step S230: pressing and molding the powder after aging to obtain a molded body;

[0088] Step S240: sending the formed green body into a drying kiln for drying to obtain a ceramic green body with a moisture content of less than 0.5%. The temperature of the ceramic green body when it leaves the drying kiln is 120-150°C.

[0089] Specifically, in step S210, an appropriate amount of water is added according to the blank formulation, along with 0.2-0.5% water reducer. The blank is then ball-milled into a slurry with a 325-mesh sieve residue of 0.6-1.5%. This embodiment of the present application precisely controls the fineness of the ball milling process to increase the specific surface area and promote solid-phase reactions during sintering, resulting in a higher density and improved strength of the resulting blank. The fine particles also reduce surface roughness and improve gloss after glazing. Furthermore, the addition of a water reducer reduces the moisture content of the slurry, reducing drying energy consumption.

[0090] In step S220, the slurry is spray-dried to produce powder. The moisture content of the powder after spraying is 6.5-7.5%. When the moisture content is controlled at 6.5-7.5%, it is suitable for the automatic press to quickly fill the mold, thereby improving the pressing efficiency. In addition, the hollow spherical particles formed by spray drying can improve the uniformity of the pressed body and reduce delamination defects.

[0091] In step S230, the dough is aged for 48 hours to allow moisture to be balanced. When pressed, a 30 MPa pressure automatic hydraulic press can be used to hydraulically form a 670 mm × 670 mm molded body.

[0092] In step S240, a ceramic body with a moisture content of less than 0.5% is obtained by drying in a drying kiln. When the surface temperature of the body reaches 120-150°C, it indicates that the internal moisture has been fully removed (residual moisture <0.5%), and the body has entered a stable state and can safely enter the next process.

[0093] The embodiment of the present application controls the ball milling fineness, controls the moisture content of the powder, and produces a ceramic body with a moisture content of less than 0.5% through kiln drying, thereby producing a ceramic body with high strength and few defects.

[0094] In one embodiment of the present application, the water reducing agent is water glass, sodium humate, sodium tripolyphosphate or sodium hexametaphosphate.

[0095] Specifically, water glass is hydrolyzed to generate OH- and silicate colloid, which makes the surface of clay particles negatively charged, disperses particles through electrostatic repulsion, reduces mud viscosity, and is inexpensive. The anions of sodium humate are adsorbed on the surface of clay particles, forming steric hindrance to prevent particle agglomeration, and are pollution-free and highly stable. 2+ Mg 2+ The long-chain phosphate groups of sodium hexametaphosphate encapsulate the particles, which, through the electrostatic-steric dual stabilization mechanism, reduces the viscosity of the mud, making it highly dispersible and allowing for long-lasting suspension.

[0096] The embodiments of the present application can use different water reducers to improve applicability, optimize particle arrangement through the water reducer, improve the flexural strength after drying, and reduce uneven sintering caused by agglomeration.

[0097] In the embodiment of the present application, the "firing in the kiln" in step S300 specifically includes: firing in an oxidizing atmosphere in a roller kiln with a firing temperature of 1120-1145°C and a firing cycle of 38-42 minutes.

[0098] The embodiments of the present application reduce the firing temperature, shorten the firing cycle, achieve low-temperature and rapid firing of ceramic tiles, and save the cost of ceramic production.

[0099] Specific embodiments are listed below for illustration.

[0100] Example 1:

[0101] The raw materials of the green body, calculated by mass percentage, include red mud: 70%, potassium sand: 10%, sodium stone powder: 10%, and fly slag: 10%. Its chemical composition, calculated by mass percentage, includes: SiO2 31.91%, Al2O3 20.04%, CaO 3.95%, MgO0.44%, K2O 1.72%, Na2O 4.37%, Fe2O3 26.29%, TiO2 2.61%, and the loss on ignition is 8.67%.

[0102] After ball milling, drying and forming, the fracture modulus of the green body was 3.59 MPa, and the fracture modulus of the tile after firing was 71.69 MPa. The phase composition ratio in the formulation of Example 1 was shown in Table 1.

[0103] Table 1

[0104]

[0105]

[0106] Example 2:

[0107] The raw materials of the green body, calculated by mass percentage, include red mud: 45%; potassium sand: 11%; sodium stone powder: 10%; fly slag: 25%; bentonite: 10%; magnesia soil: 4%; its chemical composition, calculated by mass percentage, includes: SiO2 38.25%, Al2O3 23.76%, CaO 2.86%, MgO 1.92%, K2O 1.01%, Na2O 2.74%, Fe2O3 21.19%, TiO2 1.87%, and the loss on ignition is 6.39%.

[0108] After ball milling, drying and molding, the fracture modulus of the green body was 2.86 MPa, and the fracture modulus of the tile after firing was 76.53 MPa. The phase composition ratio in the formulation of Example 2 was shown in Table 2.

[0109] Table 2

[0110]

[0111] The physical composition of conventional silicon-alumina formula ceramic bricks is shown in Table 3.

[0112] Table 3

[0113]

[0114] It can be seen from the physical composition of the two examples that the main phases of the two are crystals such as hematite, calcium (sodium) feldspar, quartz, mullite, alumina, rutile, etc., and the amorphous phase material is significantly lower than the conventional silicon-aluminum formula, which makes the ceramic bricks after adding red mud and fly slag have very high strength, toughness and wear resistance.

[0115] The present invention achieves the following effects:

[0116] First, the ceramic products prepared in this application overturn the traditional silicon-aluminum ceramic formula. While lowering the firing temperature, the crystalline phase content in the ceramic is greatly increased and richer, making the strength, toughness and wear resistance of the ceramic products significantly better than traditional silicon-aluminum ceramic products.

[0117] Second, the ceramic products prepared by the present invention have developed a new formulation system under the situation that traditional ceramic resources are becoming increasingly scarce, which makes the resource utilization scope of building ceramics wider and also saves huge costs for the production of building ceramics.

[0118] Third, the architectural ceramics prepared by the present invention improve resource utilization efficiency while reducing the firing temperature, thereby achieving cost reduction and efficiency improvement.

[0119] Fourth, the present invention greatly improves the utilization rate of industrial tailings and effectively reduces the harm caused by long-term accumulation of industrial tailings to land and groundwater.

[0120] The present invention provides a high-strength ceramic tile based on fly ash and red mud, and a preparation method thereof. The raw materials used in the ceramic body of the high-strength ceramic tile, by mass percentage, include: 40-70% red mud, 10-30% fly ash, 8-15% sodium stone powder, 8-15% potassium sand, 0-12% clay, and 0-6% magnesia. The embodiments of the present application can rationally utilize large amounts of red mud and fly ash, saving resources for ceramic production and reducing firing temperatures. At the same time, the crystalline phase content in the ceramic is significantly increased and enriched, thereby improving the strength, toughness, and wear resistance of the ceramic tile.

[0121] It should be understood that the application of the present invention is not limited to the above examples. For those skilled in the art, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A high-strength ceramic brick based on fly slag and red mud, characterized in that: The raw materials used in the ceramic body of the high-strength ceramic brick include, by mass percentage: Red mud 40-70%, pulverized coal slag 10-30%, sodium stone powder 8-15%, potassium sand 8-15%, clay 0-12%, magnesia soil 0-6%.

2. The high-strength ceramic brick based on fly slag and red mud according to claim 1, characterized in that The chemical components of the ceramic body of the high-strength ceramic brick, calculated by mass percentage, include: SiO2 32.1~40.6%, Al2O3 19.5~26.5%, CaO 2.30~4.25%, MgO0.40~2.93%, K2O0.78~1.13%, Na2O 3.32~4.69%, Fe2O3 20.57~27.94%, TiO2 2.02~3.48%, loss on ignition 5.92~8.76%.

3. The high-strength ceramic brick based on fly slag and red mud according to claim 1, characterized in that The rupture modulus of the ceramic body of the high-strength ceramic brick is 4 to 6 MPa.

4. The high-strength ceramic brick based on fly ash and red mud according to claim 1, characterized in that The chemical components of the red mud, calculated by mass percentage, include: SiO2 16~25%, Al2O3 19~25%, CaO 4~7%, MgO 0~1.5%, K2O0.5~1.5%, Na2O 4~7%, Fe2O3 30~36%, TiO2 3~5%, loss on ignition 8~10%.

5. The high-strength ceramic brick based on fly slag and red mud according to claim 1, characterized in that The chemical components of the fly ash are calculated by mass percentage and include: Loss on ignition 0.25%~1.16%, Al2O3 25%~35%, SiO2 45.35~58.88%, Fe2O34.65~5.97%, CaO 4.05~6.71%, MgO 0.25~1.55%, K2O 0.1~1.55%, Na2O0.15~1.01%.

6. The high-strength ceramic brick based on fly slag and red mud according to claim 1, characterized in that: The clays include ball clay, kaolin and / or bentonite.

7. A method for preparing high-strength ceramic bricks based on fly ash and red mud according to any one of claims 1 to 6, characterized in that: include: Mixing 40-70% of red mud, 10-30% of pulverized coal slag, 8-15% of sodium stone powder, 8-15% of potassium sand, 0-12% of clay, and 0-6% of magnesia soil by mass to obtain a mixed raw material; The mixed raw materials are ball-milled, powdered, aged, pressed into shape, and dried to obtain a ceramic body; The ceramic body is glazed, decorated with printing, and coated with brick base slurry, and then fired in a kiln to produce high-strength ceramic tiles.

8. The method for preparing high-strength ceramic bricks based on fly slag and red mud according to claim 7, characterized in that: The mixed raw materials are ball-milled, powdered, aged, pressed into shape, and dried to obtain a ceramic body, comprising: After adding water and water reducing agent to the mixed raw materials, the mixed raw materials are fed into a ball mill and milled into a slurry with a 325 mesh sieve residue of 0.6-1.5%; The slurry is spray-dried to obtain a powder, wherein the moisture content of the powder is 6.5-7.5%; Pressing and molding the powder after aging to obtain a molded body; The formed green body is sent to a drying kiln for drying to obtain a ceramic green body with a moisture content of less than 0.5%. The temperature of the ceramic green body when it leaves the drying kiln is 120-150°C.

9. The method for preparing high-strength ceramic bricks based on fly slag and red mud according to claim 8, characterized in that: The water reducing agent is water glass, sodium humate, sodium tripolyphosphate or sodium hexametaphosphate.

10. The method for preparing high-strength ceramic bricks based on fly slag and red mud according to claim 7, characterized in that: Kiln firing includes: It is fired in an oxidizing atmosphere in a roller kiln with a firing temperature of 1120-1145°C and a firing cycle of 38-42 minutes.

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