Recycled ceramic waste residue, ceramic tile blank and preparation method of ceramic tile blank

Abstract

The invention relates to the technical field of ceramics, in particular to a ceramic recycled waste residue, a ceramic green brick and a preparation method thereof. The preparation method of the ceramic recovery waste residue comprises the following steps: S10, carrying out primary crushing and intermediate crushing on a waste residue raw material, so that the waste residue raw material forms fine particles with the particle size of less than 1mm; s20, the fine particles are subjected to primary magnetic separation iron removal treatment and secondary magnetic separation iron removal treatment, so that the iron content in the fine particles is reduced to be smaller than 0.5%; and S30, the fine particles are sequentially subjected to acid pickling, complexing heavy metal removal and surface modification treatment, and the recycled waste residues are obtained. After the recycled waste residues are subjected to crushing, iron removal, acid pickling, heavy metal removal through complexing and surface modification treatment, the influence on the quality of the green bricks can be effectively reduced, the use amount of the waste residues in the green bricks is increased, and the recycling rate is increased. In addition, by optimizing the formula of the ceramic tile blank, the performance of the ceramic tile blank cannot be reduced due to high-content use of the recycled waste residues.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramics, and particularly relates to a ceramic recycled waste residue, a ceramic tile blank and a preparation method thereof. Background Art

[0002] At present, the waste residues generated in the production process of ceramic factories mainly include gutter sediments, edge grinding waste residues and polishing waste residues. The existing treatment methods for waste residues are mainly to use a small amount as raw materials for the blank body, for the production of low-grade ceramic tile blanks. However, with the upgrading of products, the current low-grade ceramic market is sluggish, the amount of waste residue used in the blank body is small, and a large amount of waste residue cannot be better recycled. At present, the recycling ratio of waste residue in the blank body is generally between 3% and 6%, while the generation rate of waste residue is 8% - 10%, far from reaching the level of completely treating waste residue.

[0003] In addition, the application of waste residue in the production of the blank body also brings various quality problems, such as: the waste residue is likely to cause defects such as prickly heat and pinholes on the surface of the product; the use of waste residue will cause a decrease in the whiteness of the blank body, affecting the appearance of the product and resulting in a reduction in product quality; the use of waste residue will also cause a decrease in the breaking strength of the blank body after firing, affecting the scope of use and service life.

[0004] It can be seen that the existing technology still needs to be improved. Summary of the Invention

[0005] In view of the above deficiencies of the existing technology, the purpose of the present invention is to provide a ceramic recycled waste residue, a ceramic tile blank and a preparation method thereof, aiming to improve the utilization rate of ceramic waste residue in the ceramic tile blank and reduce the negative impact on the quality of the ceramic tile blank caused by the use of ceramic waste residue.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions: The first aspect of the present invention provides a ceramic recycled waste residue, and its preparation method includes the following steps: S10. Perform primary crushing and intermediate crushing on the waste residue raw material to make the waste residue raw material form fine particles with a particle size less than 1 mm; S20. Perform primary magnetic separation for iron removal and secondary magnetic separation for iron removal on the fine particles to reduce the iron content in the fine particles to less than 0.5%; S30. Perform pickling, complexing for heavy metal removal and surface modification on the fine particles in sequence to obtain the recycled waste residue; The S30 includes the following steps: S31. Mix the waste residue fine particles with dilute hydrochloric acid with a concentration of 3% - 8%, and react at 60 - 80 °C for 1 - 2 hours; S32. Add a complexing agent to remove heavy metal ions and separate to obtain a precipitate; S33. Modify the precipitate with a silane coupling agent to obtain recycled waste residue.

[0007] For the ceramic recycled waste residue described above, during pickling, the mass ratio of the fine waste residue particles to dilute hydrochloric acid is 1:(3 - 4).

[0008] For the ceramic recycled waste residue described above, the complexing agent is EDTA or citric acid.

[0009] The second aspect of the present invention provides a ceramic brick blank using recycled waste residue. By mass percentage, its preparation raw materials include the following components: raw ore mud 6 - 10%, black mud 5 - 9%, calcined coal gangue 3 - 6%, potassium sodium feldspar powder 18 - 24%, albite powder 15 - 21%, modified bentonite 4 - 8%, ultra - white sand 2 - 6%, diopside 2 - 4%, the ceramic recycled waste residue described above 10 - 16%, waste brick particles 1 - 3%, quartz sand 3 - 7%, reinforcing agent 3 - 8%, zinc borate 0.5 - 1.5%, brightening agent 1 - 3%.

[0010] For the ceramic brick blank using recycled waste residue described above, the reinforcing agent includes nano - silica and kaolin, and the mass ratio of nano - silica to kaolin is 1:(2 - 4).

[0011] For the ceramic brick blank using recycled waste residue described above, the modified bentonite is quaternary ammonium salt intercalated modified bentonite.

[0012] The third aspect of the present invention provides a preparation method of a ceramic brick blank, which is used to prepare the ceramic brick blank using recycled waste residue described above, and includes the following steps: A01. Prepare each component according to the formula, mix evenly, add water, ball - mill, and spray - dry to obtain a powder. A02. Press the powder into shape and dry it to obtain a green body with a moisture content of 0.2 - 0.4%. A03. Fire the green body to obtain the ceramic brick blank using recycled waste residue.

[0013] For the preparation method of the ceramic brick blank described above, the firing of the green body includes the following steps: Low - temperature stage: Put the green body into a kiln, and raise the ambient temperature of the green body from room temperature to 300°C, with a heating rate of 22 - 28°C / min, and control the humidity in the kiln to be less than 30%RH. Medium - temperature stage: Raise the ambient temperature of the green body to 800°C, with a heating rate of 42 - 48°C / min, and continuously introduce air into the kiln. First high - temperature stage: Raise the ambient temperature of the green body to 1100°C, with a heating rate of 42 - 48°C / min, and then keep it at a constant temperature for 10 min. Second high-temperature stage: Raise the ambient temperature of the green body to 1250 °C at a heating rate of 42 - 48 °C / min, and then keep it at a constant temperature for 5 minutes; Slow cooling stage: Lower the ambient temperature of the green body to 800 °C at a cooling rate of less than 20 °C / min; Fast cooling stage: Turn on the air cooling to make the temperature of the green body drop at a rate of 50 - 80 °C / min.

[0014] In the method for preparing the ceramic tile green body, during the firing of the green body, when the ambient temperature of the green body is 300 - 900 °C, control the air pressure of the combustion-supporting air at 1.5 - 1.6 MPa; when the ambient temperature of the green body is 900 - 1150 °C, control the air pressure of the combustion-supporting air at 0.2 - 0.3 MPa; when the ambient temperature of the green body is 1150 - 1250 °C, control the air pressure of the combustion-supporting air at 0.7 - 0.8 MPa.

[0015] In the method for preparing the ceramic tile green body, in A01, the moisture content of the powder is 6 - 7%.

[0016] Beneficial effects: In the first aspect of the present invention, a ceramic recycled waste residue is provided. The ceramic recycled waste residue is obtained by sequentially subjecting the waste residue to crushing, magnetic separation, pickling, complexing to remove heavy metals, and surface modification treatment, effectively removing some impurities therein, and improving the plasticity through surface modification, which can effectively reduce the adverse effects on the quality of the green body, thereby improving the recycling rate.

[0017] In the second aspect of the present invention, a ceramic tile green body using recycled waste residue is provided. The ceramic tile green body optimizes the formula, increases the usage amount of the ceramic recycled waste residue in the formula, increases the recovery rate of the waste residue, and solves the quality problems such as low breaking strength, prickly heat, pinhole defects, and low whiteness of the product caused by the use of recycled waste residue by adopting components such as reinforcing agents, zinc borate, and brightening agents.

[0018] In the third aspect of the present invention, a method for preparing a ceramic tile green body is provided. The preparation method effectively reduces the generation of product defects by optimizing the temperature change and oxygen content change in the firing process, and makes the breaking strength of the product meet the usage requirements, enabling more ceramic waste residues to be recycled and applied to the production of medium and high-end products. Description of the Drawings

[0019] Figure 1 It is a product picture of Example 1.

[0020] Figure 2 It is a product picture of Comparative Example 1. Detailed Description of the Invention

[0021] The present invention provides a ceramic recycled waste residue, a ceramic brick blank and a preparation method thereof. To make the objectives, technical solutions and effects of the present invention clearer and more definite, the following further describes the present invention in detail with reference to the accompanying drawings and by way of examples. It should be understood that the specific examples described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] In a first aspect of the present invention, a ceramic recycled waste residue is provided, and its preparation method includes the following steps: S10. Perform primary crushing and intermediate crushing on the waste residue raw material so that the waste residue raw material forms fine particles with a particle size less than 1 mm; During primary crushing, a jaw crusher or a counterattack crusher can be used to crush the waste residue raw material into coarse particles with a particle size less than 10 mm and remove large impurities; Then, a cone crusher or a roller press is used for intermediate crushing to further refine the coarse particles with a particle size less than 10 mm to less than 1 mm. During crushing, uncompletely crushed particles can be separated through a vibrating screen (screen aperture 0.5 - 1 mm) for secondary treatment. A finer particle size is beneficial to increasing the surface area of the waste residue raw material, and it will be easier to remove iron and other impurities subsequently.

[0023] S20. Perform primary magnetic separation for iron removal and secondary magnetic separation for iron removal on the fine particles so that the iron content in the fine particles is reduced to less than 0.5%; During primary magnetic separation for iron removal: a permanent magnet drum magnetic separator (magnetic field strength ≥ 0.8 T) can be used to perform dry magnetic separation on the fine particle waste residue to remove large particle ferromagnetic substances; During secondary magnetic separation for iron removal, a high-gradient magnetic separator (magnetic field strength 1.2 - 1.5 T) can be used for wet magnetic separation to separate micron-sized iron oxides (such as Fe2O3, Fe3O4).

[0024] S30. Perform pickling, complexing for heavy metal removal and surface modification on the fine particles in sequence to obtain the recycled waste residue.

[0025] Pickling can dissolve free metal and oxide impurities such as calcium and aluminum in the fine particle waste residue, and avoid the formation of pore defects due to melting and volatilization during sintering of the recycled waste residue.

[0026] Preferably, pickling can be carried out by the following steps: mixing the waste residue with dilute hydrochloric acid with a concentration of 3 - 8% in a reaction kettle, the mass ratio of the waste residue to the dilute hydrochloric acid is 1:(3 - 4), and then stirring and reacting at 60 - 80 °C for 1 - 2 hours to fully dissolve free metal and oxide impurities such as calcium and aluminum.

[0027] Preferably, complexing for heavy metal removal can be carried out by the following steps: adding a complexing agent to the recycled material after pickling to complex heavy metal ions (such as Pb 2+ 、Cd 2+), after forming a stable complex, it is removed by centrifugation to obtain a precipitate; Preferably, the complexing agent is EDTA or citric acid, and the addition amount is 0.5-1.5% of the dry mass of the recycled material after pickling.

[0028] In surface modification: The waste residue can be surface-coated with a silane coupling agent (KH-550 or KH-570) (the addition amount is 0.2-0.5%) to improve its interfacial bonding force with the binder and increase plasticity, thereby obtaining recycled waste residue.

[0029] Through the three-step method of "pickling - complexing - modification", the heavy metal content in the waste residue can be reduced to ≤50 ppm (meeting the GB5085.3-2007 standard), and the active sites of hydroxyl groups (-OH) on the surface of the waste residue are increased, promoting sintering densification, ensuring the densification of the green body in subsequent firing, and increasing the strength of the green body.

[0030] In the second aspect of the present invention, a ceramic tile green body using recycled waste residue is provided. By mass percentage, its preparation raw materials include the following components: raw ore mud 6-10%, black mud 5-9%, calcined coal gangue 3-6%, potassium and sodium feldspar powder 18-24%, albite powder 15-21%, modified bentonite 4-8%, ultra-white sand 2-6%, diopside 2-4%, ceramic recycled waste residue 10-16%, waste brick particles 1-3%, quartz sand 3-7%, reinforcing agent 3-8%, zinc borate 0.5-1.5%, brightening agent 1-3%.

[0031] Specifically, the preparation raw materials of the ceramic tile green body further include a dispersant, and the addition amount of the dispersant is 0.15-0.3% of the sum of the masses of the above components.

[0032] Among the above components, zinc borate acts as a bubble inhibitor and decomposes into B2O3 at 800-1000 °C, covering the surface of the waste residue particles, inhibiting the oxidation and gas release of elements such as Fe and Ca, and can inhibit the escape of sintering gas at high temperature, avoiding the generation of problems such as prickly heat and pinhole defects.

[0033] The brightening powder is used to compensate for the influence of the waste residue color. Specifically, titanium dioxide (particle size of 0.5-1 micron) can be used. The high refractive index characteristic of titanium dioxide can compensate for the dull tone of the waste residue, making the whiteness of the green body ≥85%.

[0034] Under the synergistic effect of zinc borate and the brightening powder, the problems of surface defects and insufficient whiteness of the green body caused by the use of high-content recycled waste residue can be effectively solved.

[0035] The reinforcing agent is used to improve the strength performance of the green body. Preferably, the reinforcing agent includes nano-silica and kaolin, and the mass ratio of nano-silica to kaolin is 1:(2-4). Further, the particle size of the nano-silica is 20-50 nm, which is used to fill the micropores of the green body. The nano-silica enhances the bonding force between particles through the "nano effect" and reduces the sintering shrinkage stress. However, the dosage of nano-silica should not be too much, otherwise it is easy to form agglomeration, and the coordinated action with kaolin can avoid the agglomeration problem. In addition, kaolin can also provide an aluminum source, and react with SiO2 in the waste residue to form mullite phase (3Al2O3·2SiO2) at high temperature, significantly improving the compressive strength of the green body (≥15 MPa).

[0036] Preferably, the modified bentonite is quaternary ammonium salt intercalated modified bentonite. Using sodium bentonite treated by quaternary ammonium salt intercalation, its layer spacing is expanded to 1.5-2.0 nm, improving the adsorption capacity and reducing the dry cracks caused by water evaporation.

[0037] Through the optimization of the formula, the present invention solves the problems of glaze pockmarks and pinhole defects that are easily caused after using the waste residue. The whiteness of the green body after using the waste residue is not affected by the waste residue, and the production of high-quality ceramics can still be achieved, solving the problem of the decline in product quality caused by using the waste residue. All the waste residue in the overall formula can be recycled, achieving pollution-free and waste-free.

[0038] The third aspect of the present invention provides a preparation method of a ceramic tile green body, which is used to prepare the ceramic tile green body using recycled waste residue as described above, and includes the following steps: A01. Prepare each component according to the formula, mix evenly, add water, ball mill, and spray dry to obtain a powder; A02. Press the powder into shape and dry it to obtain a green body with a moisture content of 0.2-0.4%; A03. Fire the green body to obtain the ceramic tile green body using recycled waste residue.

[0039] The preparation method of the above ceramic tile green body is as follows: Mix each component material evenly, then add 38-40 wt% of water, ball mill with a ball mill to obtain a slurry with a moisture content of 35-38%, a flow rate of 30-60 s / 100 mL, and a specific gravity of 1.70-1.75 g / mL; spray dry the slurry to form a powder with a moisture content of 6.0-7.0%; Use a stamping press or a rolling press to press the powder into a green body with the required specifications and thickness. After drying and draining, the moisture content of the green body is between 0.2-0.4%, and the dry green body strength is 1.8-2.5 Mpa.

[0040] The dried green body can be directly fired, or it can further enter the glazing equipment and the pattern printing equipment to produce the bisque body. The brick blank with printed patterns then enters the firing stage.

[0041] Preferably, the firing of the green body includes the following steps: Low-temperature stage: Put the green body into the kiln, and raise the ambient temperature of the green body from room temperature to 300 °C at a heating rate of 22 - 28 °C / min, and control the humidity in the kiln to be less than 30%RH; in the low-temperature stage, by slowly discharging the residual moisture and free water in the green body, cracking caused by steam pressure can be prevented; Medium-temperature stage: Raise the ambient temperature of the green body to 800 °C at a heating rate of 42 - 48 °C / min, and continuously introduce air into the kiln; in the medium-temperature stage, by increasing the heating rate, the oxidative decomposition of the organic binder (such as bentonite) and the residual organic matter in the waste residue can be accelerated, and by introducing air (oxygen concentration ≥ 20%), the full combustion of gases such as CO and VOCs can be promoted, reducing carbon deposition, thereby reducing the surface defects caused by the exhaust of the green body; First high-temperature stage: Raise the ambient temperature of the green body to 1100 °C at a heating rate of 42 - 48 °C / min, and then keep it at a constant temperature for 10 min; in the range of 800 - 1100 °C, SiO2 and Al2O3 in the waste residue will gradually react with kaolin to form the mullite phase (3Al2O3·2SiO2), forming a framework structure; Second high-temperature stage: Raise the ambient temperature of the green body to 1250 °C at a heating rate of 42 - 48 °C / min, and then keep it at a constant temperature for 5 min; within this temperature range, nano-silica melts to form a glass phase, filling the grain boundary pores to achieve liquid-phase sintering densification; The temperature ranges of the first high-temperature stage and the second high-temperature stage ensure the formation of the mullite crystal phase and the glass phase, filling the gaps between the crystals, increasing the strength of the product, and ensuring that the strength of the brick blank after firing is above 40 Mpa; Slow cooling stage: Lower the ambient temperature of the green body to 800 °C at a cooling rate of less than 20 °C / min to avoid microcracks caused by the rapid shrinkage of the glass phase; Fast cooling stage: Turn on the air cooling to make the temperature of the green body drop at a rate of 50 - 80 °C / min to inhibit excessive grain growth.

[0042] The design of the cooling curve can effectively prevent the generation of internal stress in the product and ensure the strength of the product.

[0043] Preferably, during the firing of the green body, the temperature range of 300-900°C is the oxidation stage. When the ambient temperature of the green body is 300-900°C, the air pressure of the combustion-supporting air is controlled at 1.5-1.6 MPa. By increasing the air volume to ensure sufficient oxygen content, the complete decomposition of organic matter can be ensured, and Fe 2+ is oxidized to Fe 3+ , reducing the risk of high-temperature reduction and blackening; The temperature range of 900-1150°C is the weak reduction stage. When the ambient temperature of the green body is 900-1150°C, the air pressure of the combustion-supporting air is controlled at 0.2-0.3 MPa. By reducing the input amount of air, a partial CO mixture (CO content is 5-8%) is generated during fuel combustion, and part of the Fe 3+ is reduced to Fe 2+ , reducing the negative impact of Fe on whiteness, and at the same time avoiding over-reduction resulting in the green body turning gray.

[0044] The temperature range of 900-1150°C is the neutral atmosphere stage. When the ambient temperature of the green body is 1150-1250°C, the air pressure of the combustion-supporting air is controlled at 0.7-0.8 MPa to inhibit the oxidation or reduction of iron ions and stabilize the mineral phase structure.

[0045] Through the "oxidation-reduction-neutral" three-stage atmosphere switching, the valence states of variable valence elements such as Fe and Ti can be regulated, reducing the color center coloration (such as the yellow spots caused by Fe 3+ ), increasing the whiteness of the green body to ≥40% (ISO 2470), and reducing the Fe2O3 coloration effect by 60%.

[0046] The firing of the brick green body of the present invention adopts a stepped heating curve, which is different from the rapid firing curve of current ceramic products. The present invention strictly controls the rates of the low-temperature dehydration stage, the medium-temperature oxidation decomposition stage, the high-temperature firing stage, and the cooling stage. The firing curve set by the present invention mainly enables the green body to exhaust gas more easily during firing through the design of the firing curve, avoiding the formation of surface prickly heat pinhole defects.

[0047] The following specific examples are given to further illustrate the present application.

[0048] Example 1 A ceramic brick green body using recycled waste residue is composed of the following components in parts by weight: 8 parts of raw ore mud, 7 parts of black mud, 4.5 parts of calcined coal gangue, 21 parts of potassium and sodium feldspar powder, 18 parts of albite powder, 6 parts of modified bentonite, 4 parts of ultra-white sand, 3 parts of diopside, 13 parts of ceramic recycled waste residue, 2 parts of waste brick particles, 5 parts of quartz sand, 5.5 parts of reinforcing agent, 1 part of zinc borate, 2 parts of brightening agent, and 0.2 part of dispersant; Among them, the preparation method of the recycled waste residue is as follows: S10. Perform primary crushing and intermediate crushing on the waste residue raw material; During primary crushing, a jaw crusher is used to crush the waste residue raw material into coarse particles with a particle size less than 10 mm, and large impurities are removed; Then, a cone crusher is used for intermediate crushing to further refine the coarse particles with a particle size less than 10 mm to less than 1 mm; S20. Perform primary magnetic separation for iron removal and secondary magnetic separation for iron removal on the fine particles; During primary magnetic separation for iron removal: A permanent magnet drum magnetic separator (magnetic field intensity ≥ 0.8 T) is used to perform dry magnetic separation on the fine particle waste residue to remove large particle ferromagnetic substances; During secondary magnetic separation for iron removal, a high-gradient magnetic separator (magnetic field intensity 1.5 T) is used for wet magnetic separation to separate micron-scale iron oxides (such as Fe2O3, Fe3O4); S30. Perform pickling, complexation for heavy metal removal, and surface modification on the fine particles in sequence; The pickling is carried out in the following steps: The fine particle waste residue is mixed with dilute hydrochloric acid with a concentration of 8% in a reaction kettle, and the mass ratio of the fine particle waste residue to the dilute hydrochloric acid is 1:3. Then, it is stirred and reacted at 70 °C for 1.5 hours to fully dissolve free metal and oxide impurities such as calcium and aluminum; The complexation for heavy metal removal is carried out in the following steps: Chelating agent EDTA is added to the recycled material after pickling, and the addition amount is 1.5% of the dry material mass of the recycled material after pickling to chelate heavy metal ions (such as Pb 2+ 、Cd 2+ ), and after forming a stable complex, it is removed by centrifugation to obtain a precipitate; The surface modification is carried out in the following steps: The precipitate is surface-coated with a silane coupling agent (KH-550) (the addition amount is 0.4%) to obtain the recycled waste residue; In this embodiment, the reinforcing agent is a composite of nano-silica and kaolin with a mass ratio of 1:3; The brightening agent is titanium dioxide; The dispersant is a polycarboxylate-based dispersant; The modified bentonite is sodium-based bentonite treated by quaternary ammonium salt intercalation; The preparation method of the ceramic tile blank includes the following steps: Mix the component materials evenly, then add 38 wt% of water, perform ball milling with a ball mill, and then obtain a powder with a moisture content of 6.5% through spray drying; Press the powder into a shape and dry to drain water. The moisture content of the dried blank is 0.3%; The printed pattern and glaze application are carried out on the dried tile blank, and then firing can be carried out subsequently to obtain a ceramic tile blank using the recycled waste residue; The tile blank enters a roller hearth kiln for firing, and the firing curve is as follows: Low - temperature stage: Place the green body into the kiln, and raise the ambient temperature where the green body is located from room temperature to 300 °C at a heating rate of 25 °C / min, and control the humidity in the kiln to be less than 30%RH; Medium - temperature stage: Raise the ambient temperature where the green body is located to 800 °C at a heating rate of 45 °C / min, and continuously introduce air into the kiln to ensure that the oxygen concentration ≥ 20%; First high - temperature stage: Raise the ambient temperature where the green body is located to 1100 °C at a heating rate of 45 °C / min, and then hold the temperature constant for 10 min; Second high - temperature stage: Raise the ambient temperature where the green body is located to 1250 °C at a heating rate of 45 °C / min, and then hold the temperature constant for 5 min; Slow cooling stage: Lower the ambient temperature where the green body is located to 800 °C at a cooling rate less than 20 °C / min; Fast cooling stage: Turn on the air cooling so that the temperature of the green body drops at a rate of 50 - 80 °C / min; During the above - mentioned firing process, when the ambient temperature where the green body is located is 300 - 900 °C, control the air pressure of the combustion - supporting air at 1.5 MPa; when the ambient temperature where the green body is located is 900 - 1150 °C, control the air pressure of the combustion - supporting air at 0.3 MPa; when the ambient temperature where the green body is located is 1150 - 1250 °C, control the air pressure of the combustion - supporting air at 0.8 MPa.

[0049] Example 2 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the amount of recycled waste residue is 10 parts, and compared with Example 1, the calcined coal gangue is increased by 2 parts and the albite is increased by 1 part.

[0050] Example 3 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the amount of recycled waste residue is 16 parts, and compared with Example 1, the calcined coal gangue is reduced by 2 parts and the albite is reduced by 1 part.

[0051] Example 4 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the amount of modified bentonite is 4 parts, and compared with Example 1, the black mud is increased by 2 parts.

[0052] Example 5 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the amount of modified bentonite is 8 parts, and compared with Example 1, the black mud is reduced by 2 parts.

[0053] Example 6 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the strengthening agent is 3 parts, and compared with Example 1, the black mud is increased by 2.5 parts.

[0054] Example 7 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the strengthening agent is 8 parts, and compared with Example 1, the black mud is reduced by 1.5 parts and the modified bentonite is reduced by 1 part.

[0055] Example 8 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of zinc borate is 0.5 part, and compared with Example 1, the quartz sand is increased by 0.5 part.

[0056] Example 9 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of zinc borate is 1.5 parts, and compared with Example 1, the quartz sand is reduced by 0.5 part.

[0057] Comparative Example 1 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that ordinary waste residue without being crushed, iron-removed, pickled, complexed and surface-modified is used to replace the recycled waste residue.

[0058] Comparative Example 2 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the firing curve is different. This comparative example adopts the conventional firing curve in the prior art, specifically as follows: Preheating zone: 60°C to 450°C, heating rate is 39°C / min; Mid-temperature zone: 450°C to 1110°C, heating rate is 65°C / min; High-temperature zone: 1110°C to 1185°C, heating rate is 25°C / min; High insulation zone: 1185°C, insulation for 5 min; Cooling stage: 1185°C to 150°C, cooling rate is 103.5°C / min.

[0059] Comparative Example 3 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the modified bentonite is 2 parts, and compared with Example 1, the calcined coal gangue is increased by 2 parts and the black mud is increased by 2 parts.

[0060] Comparative Example 4 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the modified bentonite is 10 parts, and compared with Example 1, the calcined coal gangue is reduced by 2 parts and the black mud is reduced by 2 parts.

[0061] Comparative Example 5 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the strengthening agent is 1 part, and compared with Example 1, the raw ore sludge is increased by 2 parts, the potassium-sodium feldspar is increased by 1 part, and the ultra-white sand is increased by 1.5 parts.

[0062] Comparative Example 6 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of the strengthening agent is 10 parts, and compared with Example 1, the raw ore sludge is reduced by 2 parts, the potassium-sodium feldspar is reduced by 1 part, and the ultra-white sand is reduced by 1.5 parts.

[0063] Comparative Example 7 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of zinc borate is 0 part, and compared with Example 1, the quartz sand is increased by 1 part.

[0064] Comparative Example 8 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the dosage of zinc borate is 3 parts, and compared with Example 1, the quartz sand is reduced by 2 parts.

[0065] Comparative Example 9 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the waste residue used only undergoes crushing and iron removal treatment, but does not undergo pickling, complexation, and surface modification treatment.

[0066] Comparative Example 10 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the waste residue used undergoes pickling, complexation, and surface modification treatment, but does not undergo crushing and iron removal treatment. Comparative Example 11 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the waste residue used only undergoes crushing, iron removal treatment, and pickling, but does not undergo complexation and surface modification treatment.

[0067] Comparative Example 12 A ceramic tile blank using recycled waste residue, which is different from Example 1 in that the waste residue used only undergoes crushing, iron removal treatment, complexation, and surface modification treatment, but does not undergo pickling.

[0068] Detect the strength of the green bodies and the finished ceramic tile blanks prepared in the above examples and comparative examples. The test method is as follows: Cut standard specimens, place the specimens horizontally on two support rollers, apply a load in the middle until fracture, and calculate the flexural strength: R = 3FL / 2bh 2 (F is the fracture load, L is the span, b and h are the width and thickness of the specimen).

[0069] Detection method for the whiteness of green body: Measure with a digital display whiteness meter.

[0070] Detection method for blisters and pinholes on glaze surface: Stand 1 m away from the sample product and visually observe the shape and quantity of defects.

[0071] The results of each test are as follows:

[0072] Examples 1-9 are products prepared according to the formula and preparation method of the present invention. It can be seen from the test results that the green body strength can all reach above 1.85 Mpa, the finished product strength can all reach above 43 Mpa, and the whiteness can also reach above 54 GU, meeting the usage requirements of high-quality ceramic tiles. Figure 1 The picture of the product of Example 1 is shown. It can be seen that there are no defects such as raised blisters and pinholes on the glaze surface.

[0073] In Comparative Example 1, the waste residue was not subjected to crushing, magnetic separation, pickling, complexation, and surface modification treatments. The plasticity of the waste residue was low, resulting in low green body strength, easy breakage of the product, and low breaking strength of the fired brick blank, resulting in low flexural strength. Please refer to Figure 2 , because there is a lot of organic matter in the waste residue, it causes a lot of exhaust gas during firing, resulting in more pinholes, blisters and other defects on the glaze surface. Since the iron content in the waste residue in Comparative Example 1 is relatively high, it also affects the whiteness of the brick blank.

[0074] In Comparative Example 2, firing was carried out using a conventional firing curve. Due to the large amount of waste residue used, the inappropriate firing curve resulted in less mullite crystal phase formed, resulting in low strength of the finished product. Poor control of the redox atmosphere resulted in poor whiteness of the green body. At the same time, due to the inappropriate firing rate, the exhaust gas was not smooth, affecting the surface of the product and forming more defects.

[0075] In Comparative Example 3, the amount of modified bentonite used was small. Modified bentonite has the function of optimizing the green body strength. When its amount is small, it will cause low green body strength and low finished product rate.

[0076] In Comparative Example 4, the amount of modified bentonite used was large, and the green body strength was good. However, due to the large amount of bentonite used, the whiteness of the green body decreased. At the same time, due to the excessive use of bentonite, it was difficult to exhaust gas during firing of the green body, affecting the defects on the glaze surface and resulting in more defects.

[0077] In Comparative Example 5, the amount of the strengthening agent used was small, directly affecting the strength of the green body and the finished product.

[0078] In Comparative Example 6, the amount of the strengthening agent used was large, causing agglomeration, directly affecting the flexural strength of the finished product after firing and affecting the service performance.

[0079] In Comparative Example 7, no bubble inhibitor was used, resulting in a large amount of bubbles during firing, which led to a low strength of the finished product. In addition, since the exhaust of the green body could not be inhibited, there were many glaze defects.

[0080] In Comparative Example 8, due to the large amount of bubble inhibitor used, the ZnO formed after the decomposition of the bubble inhibitor itself had the effect of reducing the formulation temperature, which affected the flexural strength and whiteness of the green body. At the same time, there was an overfiring phenomenon, which affected the quality of the glaze and caused many defects.

[0081] In Comparative Example 9, the waste residue recovered was not treated by the three-step method of "pickling, complexing, and surface modification treatment". There were many impurities in the waste residue, resulting in many glaze defects and low strength of the finished product after firing. In addition, since the waste residue was not surface-modified, the strength of the green body was low and the yield was low.

[0082] In Comparative Example 10, the waste residue recovered was not crushed and de-ironed. The particles were large and the surface energy was small, resulting in a low strength of the green body and a low yield. At the same time, without de-ironing, the whiteness after firing was low.

[0083] In Comparative Example 11, the waste residue recovered was not complexed and surface-modified, resulting in a low strength of the green body and affecting the yield of the product.

[0084] In Comparative Example 12, the waste residue recovered was not pickled, which mainly affected the whiteness of the product after firing. In addition, it contained more decomposable substances and elemental metals, resulting in many pockmarks and pinhole defects after firing.

[0085] It can be understood that for those of ordinary skill in the art, equivalent substitutions or changes can be made according to the technical solution and inventive concept of the present invention, and all such changes or substitutions should fall within the protection scope of the claims appended to the present invention.

Claims

1. A ceramic recycling waste residue, characterized in that, The preparation method comprises the following steps: S10. Conduct primary crushing and intermediate crushing on the waste residue raw material to form fine particles with a particle size less than 1 mm for the waste residue raw material; S20. Conduct primary magnetic separation for iron removal and secondary magnetic separation for iron removal on the fine particles to reduce the iron content in the fine particles to less than 0.5%; S30. Conduct pickling, complexing for heavy metal removal, and surface modification on the fine particles in sequence to obtain the recycled waste residue; The S30 comprises the following steps: S31. Mix the waste residue fine particles with dilute hydrochloric acid with a concentration of 3 - 8%, and react at 60 - 80 °C for 1 - 2 hours; S32. Add a complexing agent to remove heavy metal ions, and separate to obtain a precipitate; S33. Modify the precipitate with a silane coupling agent to obtain the recycled waste residue.

2. The ceramic recycling waste residue according to claim 1, characterized in that, During pickling, the mass ratio of the waste residue fine particles to the dilute hydrochloric acid is 1:(3 - 4).

3. The ceramic recycling waste residue according to claim 1, characterized in that, The complexing agent is EDTA or citric acid.

4. A ceramic tile blank using recycled waste residue, characterized in that, By mass percentage, its preparation raw materials comprise the following components: raw ore sludge 6 - 10%, black mud 5 - 9%, calcined coal gangue 3 - 6%, potassium and sodium feldspar powder 18 - 24%, albite powder 15 - 21%, modified bentonite 4 - 8%, ultra-white sand 2 - 6%, diopside 2 - 4%, the ceramic recycled waste residue as described in any one of claims 1 - 3 10 - 16%, waste brick particles 1 - 3%, quartz sand 3 - 7%, reinforcing agent 3 - 8%, zinc borate 0.5 - 1.5%, whitening agent 1 - 3%.

5. The ceramic tile blank using recycled waste residue according to claim 4, characterized in that, The reinforcing agent comprises nano-silica and kaolin, and the mass ratio of the nano-silica to the kaolin is 1:(2 - 4).

6. The ceramic tile blank using recycled waste residue according to claim 4, characterized in that, The modified bentonite is quaternary ammonium salt intercalated modified bentonite.

7. A method for preparing a ceramic tile blank, characterized in that, For preparing the ceramic brick blank using the recycled waste residue as described in any one of claims 4 - 6, it comprises the following steps: A01. Prepare each component according to the formula, mix evenly, add water, ball mill, and spray dry to obtain a powder; A02. Press the powder into a shape and dry to obtain a blank with a moisture content of 0.2 - 0.4%; A03. Fire the blank to obtain the ceramic brick blank using the recycled waste residue.

8. The preparation method of the ceramic tile blank according to claim 7, characterized in that, The firing of the blank comprises the following steps: Low-temperature stage: Put the blank into a kiln furnace, and raise the ambient temperature where the blank is located from room temperature to 300 °C, with a heating rate of 22 - 28 °C / min, and control the humidity in the kiln furnace to be less than 30%RH; Medium-temperature stage: Raise the ambient temperature where the blank is located to 800 °C, with a heating rate of 42 - 48 °C / min, and continuously introduce air into the kiln furnace; First high-temperature stage: Raise the ambient temperature where the blank is located to 1100 °C, with a heating rate of 42 - 48 °C / min, and then keep it at a constant temperature for 10 min; Second high-temperature stage: Raise the ambient temperature where the blank is located to 1250 °C, with a heating rate of 42 - 48 °C / min, and then keep it at a constant temperature for 5 min; Slow cooling stage: Lower the ambient temperature where the blank is located to 800 °C, with a cooling rate less than 20 °C / min; Fast cooling stage: Turn on the air cooling to make the temperature of the blank drop at a rate of 50 - 80 °C / min.

9. The preparation method of the ceramic tile blank according to claim 7, characterized in that, During the firing of the green body, when the ambient temperature of the green body is 300-900 °C, the air pressure of the combustion-supporting air is controlled at 1.5-1.6 MPa; when the ambient temperature of the green body is 900-1150 °C, the air pressure of the combustion-supporting air is controlled at 0.2-0.3 MPa; when the ambient temperature of the green body is 1150-1250 °C, the air pressure of the combustion-supporting air is controlled at 0.7-0.8 MPa.

10. The method for preparing a ceramic tile blank according to claim 7, characterized in that, In A01 as described above, the moisture content of the powder is 6-7%.

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