Method for preparing ceramic bricks to suppress high-temperature decomposition of sulfides in lithium slag

Abstract

The present application relates to the preparation method of ceramic tile for inhibiting sulfide high-temperature decomposition in lithium slag, comprising: (1) powder preparation, the raw materials are proportioned and ball milled to prepare slurry, then sent to the spray drying tower to prepare green body powder and stored for later use; (2) pressing forming, the powder is sent to the mold cavity of the press to press to obtain ceramic green body; (3) green body drying, the ceramic green body is sent to the roller kiln for drying; (4) applying cosmetic clay, the dried tile body is sprayed with cosmetic clay; (5) glaze drying, the tile body is dried by infrared rays for glaze layer humidity control, the drying temperature is 100-200 DEG C, and the drying time is 1-2 min; (6) pattern decoration, the pattern is decorated according to the product effect requirement; (7) applying protective glaze, the transparent protective glaze or digital transparent protective glaze is sprayed to decorate; (8) firing, the tile body is sent to the roller kiln for firing, the sintering temperature is 1080-1130 DEG C, the firing time is 45-65 min, and the water absorption is less than 0.5 wt%; the ceramic tile semi-finished product after firing is polished or not polished and ground, and finally the finished product ceramic tile is obtained.

Description

Technical Field

[0001] This invention belongs to the field of ceramic technology, and specifically relates to a method for preparing ceramic bricks that inhibits the high-temperature decomposition of sulfides in lithium slag. Background Technology

[0002] With the continuous expansion of the lithium extraction industry from lepidolite, the environmental problems it brings are becoming increasingly prominent. Taking 0.2% lithium content raw ore from lepidolite mines in Jiangxi Province as an example, the production of 1 ton of lithium carbonate will generate about 200 tons of tailings and about 40 tons of lithium extraction tailings. These tailings contain harmful elements such as fluorine, thallium, and tantalum. The large amount of tailings generated during the lithium extraction process will have a significant impact on the environment, which also seriously restricts the development of the lithium extraction industry.

[0003] To address the severe environmental pollution caused by tailings generated during lithium extraction, ceramic industry technicians attempted to introduce lithium slag into ceramics. However, because lithium slag contains large amounts of gypsum, sulfides, and fluorides, these substances decompose during the high-temperature sintering stage of ceramics, forming harmful substances such as sulfur trioxide, sulfur dioxide, and hydrogen fluoride. These substances easily contribute to acid rain, polluting the environment and significantly negatively impacting the performance of ceramic products. Furthermore, these substances are highly corrosive, and if they overflow during calcination, they can cause serious harm to production workers. Therefore, these sulfur- and fluorine-containing lithium slags are difficult to apply on a large scale in the production of actual ceramic bricks.

[0004] Chinese patent CN116003158A discloses a method for preparing mullite porous ceramics using lithium slag, along with related patents on mullite porous ceramics and their applications. This invention utilizes an in-situ reaction of lithium slag, alumina powder, and metallic aluminum powder to prepare low-shrinkage mullite porous ceramics. The prepared mullite porous ceramics exhibit extremely low shrinkage, reducing subsequent processing costs and achieving high-value recycling of lithium slag. While this method can achieve the preparation of mullite porous ceramics by introducing lithium slag, the application range of mullite porous ceramics is relatively narrow, with limited actual demand. Only a small portion of the lithium slag is consumed. Furthermore, the sintering temperature of mullite porous ceramics is as high as 1400–1650℃. At this high temperature, sulfides and fluorides in the lithium slag decompose into harmful substances such as sulfur trioxide and hydrogen fluoride. Therefore, the widespread application of lithium slag in mullite porous ceramics is limited.

[0005] Chinese patent CN108191230A discloses a method for preparing colored foamed glass ceramic materials using lithium tailings. This method involves mixing main materials, auxiliary materials, flux, pore-forming agents, and colorants, followed by a single high-temperature firing. Lithium tailings are the main material, and crushed glass is the auxiliary material. Fluxes include sodium fluoride, potassium carbonate, sodium silicate, mirabilite, and borax. Pore-forming agents include calcium carbonate and silicon carbide. Colorants include copper oxide, iron oxide, cobalt oxide, chromium oxide, manganese oxide, and zinc oxide. This invention enables resource recycling and reuse, has a simple preparation process, low cost, and produces foamed glass ceramics with low bulk density, uniform pore distribution, adjustable color, high compressive strength, and high added value, showing good industrialization prospects. However, the application range of colored foamed glass ceramic materials is relatively narrow, only solving a small portion of the problems of industrial lithium slag accumulation and secondary pollution. Furthermore, the production temperature is above 1000℃, and the decomposition of harmful substances in the lithium slag also limits its widespread application.

[0006] In summary, although lithium slag is currently used in the production of ceramic products, these are relatively niche products, and the actual amount of lithium slag used is small. Furthermore, the production temperatures of these products are relatively high, and the production process has not solved the problem of decomposing harmful substances such as sulfides and fluorides in lithium slag. Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0007] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for preparing ceramic bricks that inhibits the high-temperature decomposition of sulfides in lithium slag. By introducing substances such as high-iron red mud, quartz glass, high-alumina stone, and limestone into the ceramic body, which can inhibit the high-temperature decomposition of lithium slag, harmful substances such as sulfur trioxide, sulfur dioxide, and hydrogen fluoride are avoided from being generated by lithium slag during the high-temperature calcination process of ceramic bricks, thereby realizing the application of lithium slag in the production of ceramic bricks.

[0008] The technical solution of the present invention is a method for preparing ceramic bricks that inhibits the high-temperature decomposition of sulfides in lithium slag, characterized by the following steps:

[0009] (1) Powder preparation: The raw materials in the formula are mixed in proportion, ball milled into a slurry, and then sent to a spray drying tower to obtain the green body powder, which is then stored and aged for later use.

[0010] (2) Pressing and molding: The obtained powder is fed into the mold cavity of a press for pressing to obtain a ceramic green body;

[0011] (3) Drying the green body: The shaped ceramic green body is sent into a roller kiln for drying.

[0012] (4) Apply slip by applying slip to the dried brick blank using a bell-shaped or straight-line glazing method.

[0013] (5) Glaze drying: The brick blanks with applied slip are dried with infrared light to control the dryness and humidity of the glaze layer. The drying temperature is 100-200℃ and the drying time is 1-2 minutes.

[0014] (6) Decorative patterns: Decorate the product with patterns as needed to achieve the desired effect.

[0015] (7) Apply protective glaze, and then spray / sprinkle transparent protective glaze or digital transparent protective glaze for decoration;

[0016] (8) Firing: The brick blanks that have completed all the decoration steps are sent into the roller kiln for firing. The sintering temperature is controlled at 1080℃~1130℃, the firing time is controlled at 45~65min, and the water absorption rate is controlled at less than 0.5wt%. The semi-finished ceramic bricks after firing are polished or not polished and ground to finally obtain the finished ceramic bricks.

[0017] Preferably, the green body powder in step (1) is composed of the following raw materials by weight percentage: 20-30 wt% lithium slag, 15-25 wt% kaolin, 10-20 wt% high-iron red mud, 10-25 wt% quartz glass, 5-10 wt% high-alumina stone, 2-5 wt% limestone, 0-20 wt% high-sodium stone powder, 0-20 wt% high-potassium stone powder, and 0.6-2 wt% degumming agent.

[0018] Preferably, the green body powder is composed of the following chemical components by weight percentage: Al2O3 12-25wt%, SiO2 60-70wt%, K2O 2-5wt%, Fe2O3 1-4wt%, Na2O 2-5wt%, CaO 2-5wt%, MgO 0.2-0.7wt%, F 0.5-2wt%, SO3 2-5wt%, and loss on ignition 3-6wt%.

[0019] Preferably, the green body powder is composed of the following chemical components by weight percentage: Al2O3 17.12wt%–18.2wt%, SiO2 63.55wt%–64.69wt%, K2O 2.21wt%–2.81wt%, Fe2O3 2.69wt%–3.14wt%, Na2O 2.59wt%–3.11wt%, CaO 2.91wt%–3.57wt%, MgO 0.20wt%, F 0.57wt%–0.85wt%, SO3 0.71wt%–2.17wt%, and loss on ignition 3.77wt%–4.52wt%.

[0020] Preferably, the lithium slag comprises, by weight percentage: 25-30 wt% leucite, 8-15 wt% nepheline, 20-30 wt% lapis lazuli, 3-8 wt% calcium fluoride, 1-5 wt% calcined gypsum, 0.5-3 wt% gypsum, 2-5 wt% albite, 0.5-2 wt% fluorspar, 0-1 wt% mica, 0-1 wt% quartz, and 20-30 wt% amorphous phase.

[0021] The chemical composition of the lithium slag, by weight percentage, includes: Al2O3 20-25 wt%, SiO2 35-40 wt%, K2O 5-10 wt%, Fe2O3 2-4 wt%, Na2O 5-10 wt%, CaO 5-10 wt%, MgO 0.2-1 wt%, F ≤3 wt%, SO3 ≤10 wt%, and loss on ignition 3-5 wt%.

[0022] Preferably, the lithium slag comprises, by weight percentage: 28 wt% leucite, 10 wt% nepheline, 24 wt% lapis lazuli, 5 wt% calcium fluoride, 2 wt% calcined gypsum, 1 wt% gypsum, 3 wt% albite, 1 wt% fluorspar, 0.5 wt% mica, 0.5 wt% quartz, and 25 wt% amorphous phase.

[0023] The chemical composition of the lithium slag includes, by weight percentage: Al2O3 21.72wt%, SiO2 37.57wt%, K2O 7.88wt%, Fe2O3 2.88wt%, Na2O 8.94wt%, CaO 7.24wt%, MgO 0.28wt%, F 2.84wt%, SO3 7.22wt%, and loss on ignition 3.43wt%.

[0024] As a preferred embodiment, the high-iron red clay comprises, by weight percentage: 25-35 wt% quartz, 25-35 wt% kaolinite, 5-10 wt% mica, 1-3 wt% illite-mica, 5-10 wt% hematite, 0.5-1.5 wt% anatase, 1-3 wt% chlorite, 0.5-1.5 wt% potassium orthoclase, and 20-30 wt% amorphous phase.

[0025] The chemical composition of the high-iron red clay, by weight percentage, includes: Al2O3 18–23 wt%, SiO2 60–70 wt%, K2O 1–3 wt%, Fe2O3 5–10 wt%, Na2O 0.1–0.5 wt%, CaO 0.1–0.5 wt%, MgO 0.1–0.5 wt%, TiO2 0.5–1.5 wt%, and loss on ignition 5–10 wt%.

[0026] As a preferred embodiment, the high-iron red clay comprises, by weight percentage: 28 wt% quartz, 30 wt% kaolinite, 6 wt% mica, 1 wt% illite-mica, 8 wt% hematite, 1 wt% anatase, 2 wt% chlorite, 1 wt% potassium orthoclase, and 23 wt% amorphous phase material.

[0027] The chemical composition of the high-iron red clay, by weight percentage, includes: Al2O3 20.46wt%, SiO2 61.54wt%, K2O 1.80wt%, Fe2O3 8.69wt%, Na2O 0.25wt%, CaO 0.21wt%, MgO 0.48wt%, TiO2 0.45wt%, and loss on ignition 6.12wt%.

[0028] Preferably, the chemical composition of the high-alumina stone, by weight percentage, includes: Al2O3 45-50 wt%, SiO2 45-50 wt%, K2O 0.5-1.5 wt%, Fe2O3 0.5-1.5 wt%, Na2O 0.5-1.5 wt%, CaO 0.5-1.5 wt%, MgO 0.5-1.5 wt%, and loss on ignition 1-3 wt%.

[0029] Preferably, the chemical composition of the high-alumina stone, by weight percentage, includes: Al2O3 46.62wt%, SiO2 48.11wt%, K2O 0.66wt%, Fe2O3 0.94wt%, Na2O 0.54wt%, CaO 1.06wt%, MgO 0.51wt%, and loss on ignition 1.56wt%.

[0030] Preferably, the chemical composition of the green body after sintering into ceramic bricks is as follows (by weight percentage): Al2O3 17.86wt%–19.06wt%, SiO2 66.55wt%–67.47wt%, K2O 2.30wt%–2.94wt%, Fe2O3 2.82wt%–3.25wt%, Na2O 2.69wt%–3.26wt%, CaO 3.05wt%–3.71wt%, MgO 0.21wt%, F 0.60wt%–0.88wt%, SO3 1.51wt%–2.26wt%.

[0031] As a preferred embodiment, a step is provided between step (6) and step (7): drying, in which the brick blank with the pattern inkjet printed decoration is dried and shaped by electric infrared drying at a temperature of 200℃ for 150s.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) This invention applies lithium slag to the ceramic body formulation. By introducing high-iron red mud and quartz glass into the ceramic body formulation, the high-temperature decomposition of sulfides in lithium slag is inhibited. This solves the problem that minerals such as calcium fluoride, fluorescein, lapis lazuli, calcined gypsum, and raw gypsum in lithium slag decompose into harmful substances such as hydrogen fluoride and sulfur oxides at high temperatures, with decomposition temperatures exceeding 1100℃, which highly coincides with the sintering temperature of ceramic bricks, making them unsuitable for direct application in ceramic production. This invention thus realizes the recycling of lithium slag.

[0034] (2) This invention introduces a large amount of lithium slag into the ceramic body formula to replace other expensive mud and sand raw materials, which greatly reduces the firing temperature, reduces the manufacturing cost of ceramic bricks, solves the problem of tailings accumulating and occupying land, avoids tailings polluting water, air and soil resources and damaging the ecological environment, and realizes the reduction, harmlessness and resource utilization of lithium slag.

[0035] (3) The efficiency of inhibiting the high-temperature decomposition of sulfides in lithium slag depends on the form and content of the sulfide mineral phases in the fired ceramic bricks. The sulfides in lithium slag exist as lapis lazuli and gypsum mineral phases. These two minerals begin to decompose in large quantities at temperatures above 1100℃, resulting in numerous firing defects in the ceramic bricks and preventing normal production. This invention introduces high-alumina sand, high-iron red clay, and quartz glass into the green body formula to promote the formation of high-temperature stable sulfoaluminate and calcium sulfate mineral phases from lapis lazuli and gypsum during the high-temperature sintering process, thereby achieving the goal of inhibiting the high-temperature decomposition of sulfides in lithium slag.

[0036] (4) This invention, by adding high-iron red clay to the green body formula, not only improves the molding performance of the green body, but also, through the large-scale introduction of iron-containing mineral phases such as hematite and anatase, forms a CaO-Al2O3-Fe2O3-CaSO4 system in the high-temperature sintered ceramic brick. The iron phase within this system can adsorb substances such as gypsum, lapis lazuli, and Al2O3, forming a high-temperature stable calcium sulfoaluminate mineral phase (3CaO·3Al2O3) at a relatively low temperature. 3· The process involves using CaSO4 to inhibit the high-temperature decomposition of sulfides. Furthermore, by introducing a large amount of quartz glass into the green body formula, more liquid glass is formed at lower temperatures, which encapsulates sulfur-containing mineral phases such as calcium sulfate and calcium sulfoaluminate, thereby effectively inhibiting their high-temperature decomposition and broadening the application range of lithium slag in ceramic manufacturing. Attached Figure Description

[0037] Figure 1 This is a flowchart of the ceramic brick preparation process of the present invention;

[0038] Figure 2 This is the diffraction pattern of the lithium slag phase analysis of the present invention;

[0039] Figure 3This is the diffraction pattern of the phase analysis of high-speed iron red mud according to the present invention. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to embodiments and accompanying drawings:

[0041] Example 1

[0042] A process for suppressing the high-temperature decomposition of sulfides in lithium slag, ceramic bricks and their preparation methods, including the following steps:

[0043] (1) Powder preparation: The raw materials in the formula are mixed in proportion, ball milled into a slurry, and sent to a spray drying tower to obtain the green body powder, which is then stored and aged for later use.

[0044] The green body powder comprises the following raw materials by weight percentage: 20wt% lithium slag, 20wt% kaolin, 14wt% high-iron red mud, 10wt% quartz glass, 5wt% high-alumina stone, 3wt% limestone, 13wt% high-sodium stone powder, 14wt% high-potassium stone powder, and 1.0wt% degumming agent.

[0045] The above-mentioned green body formula consists of the following chemical components by weight percentage: Al2O3 18.2wt%, SiO2 63.55wt%, K2O 2.81wt%, Fe2O3 2.69wt%, Na2O 3.11wt%, CaO 2.91wt%, MgO 0.20wt%, F 0.57wt%, SO3 1.44wt%, and loss on ignition 4.52wt%.

[0046] The chemical composition of the lithium slag described in this embodiment, by weight percentage, includes: Al2O3 21.72wt%, SiO2 37.57wt%, K2O 7.88wt%, Fe2O3 2.88wt%, Na2O 8.94wt%, CaO 7.24wt%, MgO 0.28wt%, F 2.84wt%, SO3 7.22wt%, and loss on ignition 3.43wt%.

[0047] The lithium slag described in this embodiment, by weight percentage, comprises the following phases: 28 wt% leucite, 10 wt% nepheline, 24 wt% lapis lazuli, 5 wt% calcium fluoride, 2 wt% calcined gypsum, 1 wt% gypsum, 3 wt% albite, 1 wt% fluorspar, 0.5 wt% mica, 0.5 wt% quartz, and 25 wt% amorphous phase material.

[0048] The chemical composition of the high-iron red clay described in this embodiment, by weight percentage, includes: Al2O3 20.46wt%, SiO2 61.54wt%, K2O 1.80wt%, Fe2O3 8.69wt%, Na2O 0.25wt%, CaO 0.21wt%, MgO 0.48wt%, TiO2 0.45wt%, and loss on ignition 6.12wt%.

[0049] The high-iron red mud described in this embodiment comprises, by weight percentage: 28 wt% quartz, 30 wt% kaolinite, 6 wt% mica, 1 wt% illite-mica, 8 wt% hematite, 1 wt% anatase, 2 wt% chlorite, 1 wt% potassium orthoclase, and 23 wt% amorphous phase material.

[0050] The chemical composition of the high-alumina stone described in this embodiment, by weight percentage, includes: Al2O3 46.62wt%, SiO2 48.11wt%, K2O 0.66wt%, Fe2O3 0.94wt%, Na2O 0.54wt%, CaO 1.06wt%, MgO 0.51wt%, and loss on ignition 1.56wt%.

[0051] (2) Pressing and molding: The obtained powder is fed into the press mold cavity for pressing to obtain ceramic green body;

[0052] (3) Drying the green body: The formed ceramic green body is sent into a roller kiln for drying. The strength of the dried ceramic brick body is 1.8 MPa.

[0053] (4) Apply slip: Use a bell-shaped applicator to apply slip to the dried brick blanks.

[0054] (5) Glaze drying: The brick blanks after spraying the anti-diffusion agent are dried with infrared light for glaze moisture control. The drying temperature is 120℃ and the drying time is 2 minutes.

[0055] (6) Decorative patterns: Decorate the product with patterns as needed to achieve the desired effect.

[0056] (7) Drying: The brick blanks with inkjet printed patterns are dried and shaped by electric infrared drying at a temperature of 200℃ for 150 seconds.

[0057] (8) Apply a protective glaze by spraying a transparent protective glaze;

[0058] (9) Firing: The brick blanks that have completed all the decoration steps are sent into the roller kiln for firing. The sintering temperature is 1085℃ and the firing time is 50min. The semi-finished ceramic bricks after firing are then ground to finally obtain finished ceramic bricks with a water absorption rate of 0.36wt%.

[0059] The green body described in this embodiment, after being sintered into porcelain tiles, has the following chemical composition by weight percentage: Al2O3 19.06wt%, SiO2 66.55wt%, K2O 2.94wt%, Fe2O3 2.82wt%, Na2O 3.26wt%, CaO 3.05wt%, MgO 0.21wt%, F 0.60wt%, and SO3 1.51wt%.

[0060] Example 2

[0061] A process for suppressing the high-temperature decomposition of sulfides in lithium slag, ceramic bricks and their preparation methods, including the following steps:

[0062] (1) Powder preparation: The raw materials in the formula are mixed in proportion, ball milled into a slurry, and sent to a spray drying tower to obtain the green body powder, which is then stored and aged for later use.

[0063] The green body powder comprises the following raw materials by weight percentage: 25wt% lithium slag, 15wt% kaolin, 19wt% high-iron red mud, 15wt% quartz glass, 5wt% high-alumina stone, 3wt% limestone, 8wt% high-sodium stone powder, 9wt% high-potassium stone powder, and 1.0wt% degumming agent.

[0064] The above-mentioned green body formula consists of the following chemical components by weight percentage: Al2O3 17.12wt%, SiO2 64.69wt%, K2O 2.37wt%, Fe2O3 3.12wt%, Na2O 2.65wt%, CaO 3.21wt%, MgO 0.20wt%, F 0.71wt%, SO3 1.81wt%, and loss on ignition: 4.12wt%.

[0065] The chemical composition of the lithium slag described in this embodiment, by weight percentage, includes: Al2O3 21.72wt%, SiO2 37.57wt%, K2O 7.88wt%, Fe2O3 2.88wt%, Na2O 8.94wt%, CaO 7.24wt%, MgO 0.28wt%, F 2.84wt%, SO3 7.22wt%, and loss on ignition 3.43wt%.

[0066] The lithium slag described in this embodiment, by weight percentage, comprises the following phases: 28 wt% leucite, 10 wt% nepheline, 24 wt% lapis lazuli, 5 wt% calcium fluoride, 2 wt% calcined gypsum, 1 wt% gypsum, 3 wt% albite, 1 wt% fluorspar, 0.5 wt% mica, 0.5 wt% quartz, and 25 wt% amorphous phase material.

[0067] The chemical composition of the high-iron red clay described in this embodiment, by weight percentage, includes: Al2O3 20.46wt%, SiO2 61.54wt%, K2O 1.80wt%, Fe2O3 8.69wt%, Na2O 0.25wt%, CaO 0.21wt%, MgO 0.48wt%, TiO2 0.45wt%, and loss on ignition 6.12wt%.

[0068] The high-iron red mud described in this embodiment comprises, by weight percentage: 28 wt% quartz, 30 wt% kaolinite, 6 wt% mica, 1 wt% illite-mica, 8 wt% hematite, 1 wt% anatase, 2 wt% chlorite, 1 wt% potassium orthoclase, and 23 wt% amorphous phase material.

[0069] The chemical composition of the high-alumina stone described in this embodiment, by weight percentage, includes: Al2O3 46.62wt%, SiO2 48.11wt%, K2O 0.66wt%, Fe2O3 0.94wt%, Na2O 0.54wt%, CaO 1.06wt%, MgO 0.51wt%, and loss on ignition 1.56wt%.

[0070] (2) Pressing and molding: The obtained powder is fed into the press mold cavity for pressing to obtain ceramic green body;

[0071] (3) Drying the green body: The formed ceramic green body is sent into a roller kiln for drying. The strength of the dried ceramic brick body is 1.8 MPa.

[0072] (4) Apply slip: Use a bell-shaped applicator to apply slip to the dried brick blanks.

[0073] (5) Glaze drying: The brick blanks after spraying the anti-diffusion agent are dried with infrared light for glaze moisture control. The drying temperature is 120℃ and the drying time is 2 minutes.

[0074] (6) Decorative patterns: Decorate the product with patterns as needed to achieve the desired effect.

[0075] (7) Drying: The brick blanks with inkjet printed patterns are dried and shaped by electric infrared drying at a temperature of 200℃ for 150 seconds.

[0076] (8) Apply a protective glaze by spraying a transparent protective glaze;

[0077] (9) Firing: The brick blanks that have completed all the decoration steps are sent into the roller kiln for firing. The sintering temperature is 1110℃ and the firing time is 58 minutes. The semi-finished ceramic bricks after firing are then ground to finally obtain finished ceramic bricks with a water absorption rate of 0.25wt%.

[0078] The green body described in this embodiment, after being sintered into porcelain tiles, has the following chemical composition by weight percentage: Al2O3 17.86wt%, SiO2 67.47wt%, K2O 2.47wt%, Fe2O3 3.25wt%, Na2O 2.76wt%, CaO 3.35wt%, MgO 0.21wt%, F 0.74wt%, and SO3 1.89wt%.

[0079] Example 3

[0080] A process for suppressing the high-temperature decomposition of sulfides in lithium slag, ceramic bricks and their preparation methods, including the following steps:

[0081] (1) Powder preparation: The raw materials in the formula are mixed in proportion, ball milled into a slurry, and sent to a spray drying tower to obtain the green body powder, which is then stored and aged for later use.

[0082] The green body powder comprises the following raw materials by weight percentage: 30wt% lithium slag, 15wt% kaolin, 19wt% high-iron red mud, 25wt% quartz glass, 7wt% high-alumina stone, 3wt% limestone, and 1.0wt% degumming agent.

[0083] The above-mentioned green body formula consists of the following chemical components by weight percentage: Al2O3 17.25wt%, SiO2 64.25wt%, K2O 2.21wt%, Fe2O3 3.14wt%, Na2O 2.59wt%, CaO 3.57wt%, MgO 0.20wt%, F 0.85wt%, SO3 2.17wt%, and loss on ignition 3.77wt%.

[0084] The chemical composition of the lithium slag described in this embodiment, by weight percentage, includes: Al2O3 21.72wt%, SiO2 37.57wt%, K2O 7.88wt%, Fe2O3 2.88wt%, Na2O 8.94wt%, CaO 7.24wt%, MgO 0.28wt%, F 2.84wt%, SO3 7.22wt%, and loss on ignition 3.43wt%.

[0085] The lithium slag described in this embodiment, by weight percentage, comprises the following phases: 28 wt% leucite, 10 wt% nepheline, 24 wt% lapis lazuli, 5 wt% calcium fluoride, 2 wt% calcined gypsum, 1 wt% gypsum, 3 wt% albite, 1 wt% fluorspar, 0.5 wt% mica, 0.5 wt% quartz, and 25 wt% amorphous phase material.

[0086] The chemical composition of the high-iron red clay described in this embodiment, by weight percentage, includes: Al2O3 20.46wt%, SiO2 61.54wt%, K2O 1.80wt%, Fe2O3 8.69wt%, Na2O 0.25wt%, CaO 0.21wt%, MgO 0.48wt%, TiO2 0.45wt%, and loss on ignition 6.12wt%.

[0087] The high-iron red mud described in this embodiment comprises, by weight percentage: 28 wt% quartz, 30 wt% kaolinite, 6 wt% mica, 1 wt% illite-mica, 8 wt% hematite, 1 wt% anatase, 2 wt% chlorite, 1 wt% potassium orthoclase, and 23 wt% amorphous phase material.

[0088] The chemical composition of the high-alumina stone described in this embodiment, by weight percentage, includes: Al2O3 46.62wt%, SiO2 48.11wt%, K2O 0.66wt%, Fe2O3 0.94wt%, Na2O 0.54wt%, CaO 1.06wt%, MgO 0.51wt%, and loss on ignition 1.56wt%.

[0089] (2) Pressing and molding: The obtained powder is fed into the press mold cavity for pressing to obtain ceramic green body;

[0090] (3) Drying the green body: The formed ceramic green body is sent into a roller kiln for drying. The strength of the dried ceramic brick body is 1.8 MPa.

[0091] (4) Apply slip: Use a bell-shaped applicator to apply slip to the dried brick blanks.

[0092] (5) Glaze drying: The brick blanks after spraying the anti-diffusion agent are dried with infrared light for glaze moisture control. The drying temperature is 120℃ and the drying time is 2 minutes.

[0093] (6) Decorative patterns: Decorate the product with patterns as needed to achieve the desired effect.

[0094] (7) Drying: The brick blanks with inkjet printed patterns are dried and shaped by electric infrared drying at a temperature of 200℃ for 150 seconds.

[0095] (8) Apply a protective glaze by spraying a transparent protective glaze;

[0096] (9) Firing: The brick blanks that have completed all the decoration steps are sent into the roller kiln for firing. The sintering temperature is 1130℃ and the firing time is 65min. The semi-finished ceramic bricks after firing are then ground to finally obtain finished ceramic bricks with a water absorption rate of 0.08wt%.

[0097] The green body described in this embodiment, after being sintered into porcelain tiles, has the following chemical composition by weight percentage: Al2O3 17.92wt%, SiO2 66.77wt%, K2O 2.30wt%, Fe2O3 3.26wt%, Na2O 2.69wt%, CaO 3.71wt%, MgO 0.21wt%, F 0.88wt%, and SO3 2.26wt%.

[0098] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.

Claims

1. A method for producing a ceramic tile for inhibiting high-temperature decomposition of sulfides in a lithium mine residue, characterized by, The method comprises the following steps:

1. Powder preparation: raw materials in the formula are proportioned and ball milled to prepare slurry, which is then sent to a spray drying tower to prepare green body powder and stored for later use; the green body powder comprises the following raw materials in percentage by weight: lithium slag 20-30wt%, kaolin 15-25wt%, high-iron red mud 10-20wt%, quartz glass 10-25wt%, high-aluminum stone 5-10wt%, limestone 2-5wt%, high-sodium stone powder 0-20wt%, high-potassium stone powder 0-20wt%, and de-agglomerating agent 0.6-2wt%; 2. Press forming: the prepared powder is sent into a press mold cavity for press forming to obtain ceramic green body; 3. Green body drying: the formed ceramic green body is sent into a roller kiln for drying; 4. Cosmetic clay application: the dried green body is subjected to cosmetic clay application by bell jar or straight-line glaze spraying; 5. Glaze drying: the green body with applied cosmetic clay is subjected to infrared drying for glaze layer humidity control, with a drying temperature of 100-200℃ and a drying time of 1-2min; 6. Pattern decoration: decoration patterns are applied according to product effect requirements; 7. Protective glaze application: transparent protective glaze or digital transparent protective glaze is applied by spraying or spraying; 8. Sintering: the green body after all decoration steps is sent into a roller kiln for sintering, with a sintering temperature of 1080-1130℃, a sintering time of 45-65min, and a water absorption rate of 0.5wt% or less; the sintered ceramic tile semi-finished product is subjected to polishing or edge grinding without polishing to obtain a finished product ceramic tile.

2. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. The green body powder comprises the following chemical components in percentage by weight: Al2O3 12-25wt%, SiO2 60-70wt%, K2O 2-5wt%, Fe2O3 1-4wt%, Na2O 2-5wt%, CaO 2-5wt%, MgO 0.2-0.7wt%, F 0.5-2wt%, SO3 2-5wt%, and loss on ignition 3-6wt%.

3. The method of claim 1, wherein the ceramic tile is prepared by mixing the lithium slag and the ceramic tile at a temperature of 1,000°C to 1,500°C in a non-oxidizing atmosphere. The green body powder comprises the following chemical components in percentage by weight: Al2O3 17.12-18.2wt%, SiO2 63.55-64.69wt%, K2O 2.21-2.81wt%, Fe2O3 2.69-3.14wt%, Na2O 2.59-3.11wt%, CaO 2.91-3.57wt%, MgO 0.20wt%, F 0.57-0.85wt%, SO3 0.71-2.17wt%, and loss on ignition 3.77-4.52wt%; the green body powder promotes the formation of calcium sulphoaluminate mineral phase and inhibits the high-temperature decomposition of sulfide.

4. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. The lithium tailings include, in percentage by weight, 25-30wt% of leucite, 8-15wt% of nepheline, 20-30wt% of smaragd, 3-8wt% of calcium fluoride, 1-5wt% of plaster of paris, 0.5-3wt% of gypsum, 2-5wt% of albite, 0.5-2wt% of fluorophospholite LiAlPO4F, 0-1wt% of mica, 0-1wt% of quartz, and 20-30wt% of amorphous phase; The lithium tailings include, in percentage by weight, 20-25wt% of Al2O3, 35-40wt% of SiO2, 5-10wt% of K2O, 2-4wt% of Fe2O3, 5-10wt% of Na2O, 5-10wt% of CaO, 0.2-1wt% of MgO, ≤3wt% of F, ≤10wt% of SO3, and 3-5wt% of loss on ignition.

5. The method of claim 4, wherein the ceramic tile is prepared by mixing the lithium slag and the ceramic tile at a temperature of 1,000°C to 1,500°C in a non-oxidizing atmosphere. The lithium tailings include, in percentage by weight, 28wt% of leucite, 10wt% of nepheline, 24wt% of smaragd, 5wt% of calcium fluoride, 2wt% of plaster of paris, 1wt% of gypsum, 3wt% of albite, 1wt% of fluorophospholite LiAlPO4F, 0.5wt% of mica, 0.5wt% of quartz, and 25wt% of amorphous phase; The lithium tailings include, in percentage by weight, 21.72wt% of Al2O3, 37.57wt% of SiO2, 7.88wt% of K2O, 2.88wt% of Fe2O3, 8.94wt% of Na2O, 7.24wt% of CaO, 0.28wt% of MgO, 2.84wt% of F, 7.22wt% of SO3, and 3.43wt% of loss on ignition.

6. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. The high-iron red mud includes, in percentage by weight, 25-35wt% of quartz, 25-35wt% of kaolinite, 5-10wt% of mica, 1-3wt% of illite-mica, 5-10wt% of hematite, 0.5-1.5wt% of anatase, 1-3wt% of clinochlore, 0.5-1.5wt% of potassium orthoclase, and 20-30wt% of amorphous phase; The high-iron red mud includes, in percentage by weight, 18-23wt% of Al2O3, 60-70wt% of SiO2, 1-3wt% of K2O, 5-10wt% of Fe2O3, 0.1-0.5wt% of Na2O, 0.1-0.5wt% of CaO, 0.1-0.5wt% of MgO, 0.5-1.5wt% of TiO2, and 5-10wt% of loss on ignition.

7. The method of claim 6, wherein the ceramic tile is prepared by mixing the lithium slag and the ceramic tile at a temperature of 1,000°C to 1,500°C for 1 to 10 hours. The high-iron red mud includes, in percentage by weight, 28wt% of quartz, 30wt% of kaolinite, 6wt% of mica, 1wt% of illite-mica, 8wt% of hematite, 1wt% of anatase, 2wt% of clinochlore, 1wt% of potassium orthoclase, and 23wt% of amorphous phase; The high-iron red mud has a chemical composition including, in percentage by weight: Al2O3 20.46%, SiO2 61.54%, K2O 1.80%, Fe2O3 8.69%, Na2O 0.25%, CaO 0.21%, MgO 0.48%, TiO2 0.45%, and loss on ignition 6.12%.

8. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. The high-alumina stone has a chemical composition including, in percentage by weight: Al2O3 45-50%, SiO2 45-50%, K2O 0.5-1.5%, Fe2O3 0.5-1.5%, Na2O 0.5-1.5%, CaO 0.5-1.5%, MgO 0.5-1.5%, and loss on ignition 1-3%.

9. The method of claim 8, wherein the ceramic tile is prepared by mixing the lithium slag and the ceramic tile at a temperature of 1,000°C to 1,500°C for 1 to 10 hours. The high-alumina stone has a chemical composition including, in percentage by weight: Al2O3 46.62%, SiO2 48.11%, K2O 0.66%, Fe2O3 0.94%, Na2O 0.54%, CaO 1.06%, MgO 0.51%, and loss on ignition 1.56%.

10. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. After the green body is sintered into a ceramic tile, the chemical composition of the ceramic tile includes, in percentage by weight: Al2O3 17.86-19.06%, SiO2 66.55-67.47%, K2O 2.30-2.94%, Fe2O3 2.82-3.25%, Na2O 2.69-3.26%, CaO 3.05-3.71%, MgO 0.21%, F 0.60-0.88%, SO3 1.51-2.26%, and loss on ignition 0.21%.

11. The method of claim 1, wherein the ceramic tile is prepared by suppressing high-temperature decomposition of sulfides in lithium slag. The step ⑹ and the step ⑺ are provided with a step of drying, in which the green body printed with the pattern by inkjet printing is dried and shaped by electric infrared drying, the drying temperature is 200℃, and the drying time is 150s.

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