Method for preparing full-body full-ceramic tile by recycling large-particle waste ceramic and product prepared by method

Abstract

The invention discloses a method for preparing a whole-body full-ceramic tile by recovering large-particle waste porcelain and a product prepared by the method, the large-particle waste porcelain, potassium feldspar, calcite, magnesite powder, 3 mol% yttrium-stabilized zirconia and a pigment for a green body are used as raw materials, and the whole-body full-ceramic tile is prepared by preparation of a calcined material, preparation of a blank material, vibration compaction molding, drying and calcination. The full-body ceramic tile which is compact in structure, high in mechanical strength and rich in decoration effect is obtained. According to the method, high-efficiency and low-cost recycling of the large-particle waste porcelain is realized, the cost of a ceramic tile product is reduced, and a new way is provided for realizing high-added-value recycling of solid waste.

Description

Technical Field

[0001] The invention relates to the technical field of building ceramic materials, and in particular to a method for recycling large-particle waste ceramics to prepare full-body ceramic tiles and the products obtained. Background Art

[0002] The prosperous development of the ceramic industry has made a huge contribution to my country's economic construction. At the same time, defective ceramic products produced during the firing process and discarded products produced by users when replacing ceramic products cannot be directly used, and the technical difficulty and cost of secondary recycling are high, resulting in a large amount of sintered ceramic waste being disposed of by open-air stacking or landfill, which not only occupies land resources, but also causes irreversible pollution to water bodies and soil. How to efficiently and cost-effectively utilize ceramic solid waste resources is one of the technical problems that the environmental protection department and the ceramic industry need to solve urgently.

[0003] As for sintered ceramic tile waste, the common recycling method is to crush the waste ceramic blocks by primary crushing, secondary crushing, and advanced wet ball milling, and finally obtain waste ceramic powder with a particle size of 0.01-0.06 mm, which is then reused. At the same time, ceramic tile waste is a barren material with low sintering activity, so its addition amount in the ceramic formula is only 10-30wt%, resulting in high crushing cost and low recycling efficiency for the existing waste ceramic recycling products.

[0004] The particle size of commonly used ceramic raw materials is above 200 meshes, and the average particle size is less than 0.05mm. This particle size of raw materials is conducive to the forming and sintering of the green body. The technical difficulty of the secondary utilization of large-particle waste porcelain lies in its large size and irregular edges and corners, which makes it difficult to form it into a dense shape when added to the porcelain green body, and it is easy to cause defects such as stratification and cracking in the green body during the secondary sintering, which seriously damages the mechanical strength and performance of the green body. For this reason, the existing technology adopts a method of modifying the surface of large-particle waste porcelain by coating a layer of 0.5-1mm thick slurry. Although it can improve the combination of large-particle waste porcelain and other powder materials of the green body and avoid the defects of stratification and cracking in the ceramic tile, its operation process is relatively cumbersome.

[0005] Full-body tiles are low-water-absorption full-ceramic tiles with consistent color mechanism on the body surface and inside. After secondary processing such as edging, chamfering, and grooving, the exposed brick color can maintain a unified sense of design. Full-body tiles are not glazed on the surface, and the material and color of the front and back sides are consistent. They diffusely reflect when exposed to light, reducing the impact of light pollution on the surrounding environment. Therefore, full-body tiles are widely welcomed in the field of indoor and outdoor wall decoration. If large-particle waste porcelain can be used to prepare full-body tiles with dense structure, high mechanical strength, and rich decorative effects, it will be conducive to the efficient and low-cost recycling of large-particle waste porcelain, and provide a new way to achieve high-value-added reuse of solid waste. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for recycling large-particle waste porcelain to prepare full-body ceramic tiles, using large-particle waste porcelain, potassium feldspar, calcite, magnesite powder, 3mol% yttrium-stabilized zirconia, and body colorant as raw materials to prepare full-body ceramic tiles, so as to reduce the cost of ceramic tile products, improve the comprehensive utilization rate of solid waste and high added value utilization. Another purpose of the present invention is to use the products prepared by the above preparation method.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] The present invention provides a method for recycling large-particle waste porcelain to prepare full-body ceramic tiles, comprising the following steps:

[0009] (1) Preparation of calcined material

[0010] 60-70 parts of potassium feldspar, 10-20 parts of calcite and 10-20 parts of magnesite powder are dry mixed according to weight proportions, and the obtained mixture is calcined at 900-1000° C., and sifted to obtain a calcined material;

[0011] (2) Preparation of blanks

[0012] (2-1) dry-mixing 10 to 20 parts of a calcined material, 1 to 3 parts of 3 mol% yttrium-stabilized zirconia, and 0 to 5 parts of a body colorant according to weight proportions to obtain a body strengthening material;

[0013] (2-2) adding 50-60 parts of large-particle waste porcelain with a particle size of 4-5 mesh and 20-30 parts of fine-particle waste porcelain with a particle size of 40-80 mesh to the green body reinforcement material and continuing dry mixing to obtain a mixed material;

[0014] (2-3) adding a 0.5 wt % hydroxypropyl methylcellulose aqueous solution to the mixture by spraying, wherein the amount is 8 to 12 wt % of the mixture, and stirring and aging to obtain a blank;

[0015] (3) Vibration compaction molding

[0016] The blank is poured into a vibration molding machine, and vibration compaction molding is performed according to the process parameters of vibration frequency 5-15 Hz, exciting force 6000-6500 N, static pressure 1300-1800 N, and compaction time 5-15 s to obtain a green blank with a thickness of 12-15 mm;

[0017] (4) Drying and calcination

[0018] The green body is dried and placed in a kiln, heated to 1200-1240°C at a rate of 20°C / min, kept at the highest temperature for 0.5-1h, and then naturally cooled to room temperature to obtain a full-body ceramic tile prepared by recycling large-particle waste porcelain.

[0019] Furthermore, in the step (2-1) of the present invention, the main crystalline phase of the green body strengthening material is Zr 0.963 Y 0.037 O 1.982 , the amorphous phase content is greater than 85%, the initial melting temperature of the green body reinforcement material is 1160-1180°C, and the shrinkage rate of the sintered body at 1250°C is less than 2%.

[0020] Furthermore, the waste porcelain of the present invention is obtained by crushing the waste of building ceramics and sanitary ceramics with a sintering temperature in the range of 1160-1220°C, and the tap density of the large particles of 4-5 mesh waste porcelain is 1.3-1.4 g / cm 3 The tap density of 40-80 mesh fine waste porcelain is 1.5-1.6 g / cm 3 The tap density of the calcined material is 0.8 to 0.9 g / cm 3 .

[0021] Furthermore, the particle size of the 3 mol% yttrium stabilized zirconia of the present invention is 1-2 μm. The green body colorant is a cobalt blue colorant for ceramic green body decoration, such as praseodymium yellow, cobalt blue, and chrome green.

[0022] In the above scheme, in the step (1) of the present invention, the residue on the calcined material after passing through 200 mesh is less than 0.2%; the time of the dry mixing is 0.5 to 1 hour; the stirring time in the step (2-3) is 0.5 to 1 hour, and the aging time is 3 to 5 days; the porosity of the green body in the step (3) is less than 0.5%.

[0023] The product prepared by the method of recycling large-particle waste porcelain to prepare full-body ceramic tiles of the present invention has a flexural strength of more than 30 MPa and a water absorption rate of less than 0.5%.

[0024] The present invention has the following beneficial effects:

[0025] (1) The present invention uses waste porcelain and a small amount of mineral raw materials to prepare full-body ceramic tiles. The utilization rate of waste porcelain is more than 85%, and more than 60% are large-particle waste porcelain of 4-5 mesh, which reduces the cost of recycling, processing and crushing of waste porcelain. Through vibration compaction molding and rapid sintering process, full-body ceramic tiles can be prepared, and dense and high-strength brick bodies can be obtained without glazing. The addition of body colorants can enrich the decorative effect of full-body tiles. The surface and cross-section textures of the brick bodies are consistent throughout the body, accompanied by large-particle waste porcelain decoration and body colorant decoration. It can be widely used in interior / exterior wall art decoration to achieve high added value utilization of solid waste.

[0026] (2) The present invention first pre-calcines the mixture of potassium feldspar, calcite and magnesite powder, which can improve the activity of the secondary sintering of the powder, greatly reduce the shrinkage of the sintering of the powder, and avoid the internal stratification, cracking and deformation of the whole brick caused by the sintering shrinkage of the powder. The green body reinforcement material has a high degree of vitrification and low volume shrinkage at high temperature, and the dispersed Zr 0.963 Y 0.037 O 1.982 Crystals can improve the strength and toughness of the whole body brick. A small amount of zirconium oxide melts in the amorphous phase to increase the high-temperature viscosity of the body reinforcement material, reduce the deformation of the whole body brick, promote the densification of the whole body brick, and reduce defects such as internal cracking and external deformation caused by inconsistent melting shrinkage.

[0027] (3) The present invention uses large-particle waste porcelain as the skeleton of the whole body brick, and fine-particle waste porcelain and body reinforcement materials as void fillers of the skeleton to promote the sliding behavior of large-particle waste porcelain during the vibration molding process. The minimum addition amount of fine-particle waste porcelain and body reinforcement materials is determined by the tap density of large-particle waste porcelain, fine-particle waste porcelain and body reinforcement materials. Lower vibration frequency and higher pressure are conducive to uniform mixing and compacting of large-particle waste porcelain and powder materials. Medium static pressure can ensure that large-particle waste porcelain will not be fractured and cause defects inside the body. Combined vibration compaction molding improves the density of the whole body brick green body, avoids the defects of large-particle waste porcelain being broken under high pressure and having pores under low pressure, and solves the technical difficulties of large-particle waste porcelain being reused in large quantities in ceramic tiles, resulting in internal stratification and cracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings:

[0029] Figure 1 Process flow chart of the preparation method of the embodiment of the present invention;

[0030] Figure 2 XRD spectrum of the green body reinforcement material after sintering at 1250° C. in the preparation method of the embodiment of the present invention;

[0031] Figure 3 Appearance of the full-body ceramic tile prepared in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] Embodiment 1:

[0033] This embodiment provides a method for recycling large particles of waste porcelain to prepare full-body ceramic tiles, such as Figure 1 As shown, the steps are as follows:

[0034] (1) Preparation of calcined material

[0035] 68 parts of potassium feldspar, 20 parts of calcite and 12 parts of magnesite powder were dry mixed for 0.5 hours according to weight, and the obtained mixture was calcined at 900°C to obtain a calcined material with a residue of 0.05% after passing through 200 mesh;

[0036] (2) Preparation of blanks

[0037] (2-1) 12 parts of calcined material and 2 parts of 3 mol% yttrium stabilized zirconia were dry mixed for 0.5 h to obtain a green body strengthening material; Figure 2 As shown, the main crystal phase of the green body strengthening material is Zr 0.963 Y 0.037 O 1.982 , the amorphous phase content is 89.2%, the initial melting temperature is 1160℃, and the shrinkage rate of the sintered body at 1250℃ is 1.2%;

[0038] (2-2) adding 58 parts of large-particle waste porcelain with a particle size of 4 to 5 meshes and 28 parts of fine-particle waste porcelain with a particle size of 40 to 80 meshes to the green body reinforcement material and continuing dry mixing for 1 hour to obtain a mixed material;

[0039] (2-3) adding a 0.5 wt % hydroxypropyl methylcellulose aqueous solution to the mixture by spraying, wherein the amount is 9 wt % of the mixture, stirring for 1 hour, and aging for 3 days to obtain a blank;

[0040] (3) Vibration compaction molding

[0041] The above blank was poured into a vibration molding machine, and vibration compaction molding was performed according to the process parameters of vibration frequency 5 Hz, exciting force 6200 N, static pressure 1500 N, and compaction time 10 s to obtain a dense green blank with a thickness of 12 mm and a porosity of 0.3%;

[0042] (4) Drying and calcination

[0043] The green body is dried and placed in a kiln, heated to 1200°C at a rate of 20°C / min, kept at the highest temperature for 0.5h, and then naturally cooled to room temperature to obtain a full-body ceramic tile made from recycled large-particle waste porcelain.

[0044] Embodiment 2:

[0045] This embodiment provides a method for recycling large particles of waste porcelain to prepare full-body ceramic tiles, such as Figure 1 As shown, the steps are as follows:

[0046] (1) Preparation of calcined material

[0047] 65 parts of potassium feldspar, 18 parts of calcite and 17 parts of magnesite powder were dry mixed for 0.5 hours according to weight, and the obtained mixture was calcined at 950°C to obtain a calcined material with a residue of 0.05% after passing through a 200 mesh screen;

[0048] (2) Preparation of blanks

[0049] (2-1) 19 parts of calcined material, 1 part of 3 mol% yttrium stabilized zirconia, and 5 parts of green body colorant were dry mixed for 0.5 h to obtain a green body reinforcement material; the main crystal phase of the green body reinforcement material is Zr 0.963 Y 0.037 O 1.982 , the amorphous phase content is 87.8%, the initial melting temperature is 1165℃, and the shrinkage rate of the sintered body at 1250℃ is 1.4%;

[0050] (2-2) adding 50 parts of large-particle waste porcelain with a particle size of 4 to 5 meshes and 25 parts of fine-particle waste porcelain with a particle size of 40 to 80 meshes to the green body reinforcement material and continuing dry mixing for 1 hour to obtain a mixed material;

[0051] (2-3) adding a 0.5 wt % hydroxypropyl methylcellulose aqueous solution to the mixture by spraying, wherein the amount is 12 wt % of the mixture, stirring for 1 hour, and aging for 5 days to obtain a blank;

[0052] (3) Vibration compaction molding

[0053] The above blank was poured into a vibration molding machine, and vibration compaction molding was performed according to the process parameters of vibration frequency 15 Hz, exciting force 6400 N, static pressure 1600 N, and compaction time 10 s to obtain a dense green blank with a thickness of 13 mm and a porosity of 0.45%;

[0054] (4) Drying and calcination

[0055] The green body is dried and placed in a kiln, and the temperature is raised to 1220°C at a rate of 20°C / min. After being kept at the highest temperature for 0.5h, it is naturally cooled to room temperature to obtain a full-body ceramic tile prepared by recycling large-particle waste porcelain.

[0056] Embodiment three:

[0057] This embodiment provides a method for recycling large particles of waste porcelain to prepare full-body ceramic tiles, such as Figure 1 As shown, the steps are as follows:

[0058] (1) Preparation of calcined material

[0059] 62 parts of potassium feldspar, 18 parts of calcite and 20 parts of magnesite powder were dry mixed for 0.5 hours according to weight, and the obtained mixture was calcined at 1000°C to obtain a calcined material with a residue of 0.05% after passing through 200 mesh;

[0060] (2) Preparation of blanks

[0061] (2-1) 15 parts of calcined material, 2 parts of 3 mol% yttrium stabilized zirconia, and 3 parts of green body colorant were dry mixed for 0.5 h to obtain green body strengthening material; Figure 1 As shown, the main crystal phase of the green body strengthening material is Zr 0.963 Y 0.037 O 1.982 , the amorphous phase content is 92.5%, the initial melting temperature is 1175℃, and the shrinkage rate of the sintered body at 1250℃ is 1.8%;

[0062] (2-2) adding 55 parts of large-particle waste porcelain with a particle size of 4 to 5 meshes and 25 parts of fine-particle waste porcelain with a particle size of 40 to 80 meshes to the green body reinforcement material and continuing dry mixing for 1 hour to obtain a mixed material;

[0063] (2-3) adding a 0.5 wt % hydroxypropyl methylcellulose aqueous solution to the mixture by spraying, wherein the amount is 10 wt % of the mixture, stirring for 1 hour, and aging for 4 days to obtain a blank;

[0064] (3) Vibration compaction molding

[0065] The above blank was poured into a vibration molding machine, and vibration compaction molding was performed according to the process parameters of vibration frequency 12 Hz, exciting force 6500 N, static pressure 1700 N, and compaction time 15 s to obtain a dense green blank with a thickness of 14 mm and a porosity of 0.15%;

[0066] (4) Drying and calcination

[0067] The green body is dried and placed in a kiln, and the temperature is raised to 1240°C at a rate of 20°C / min. After being kept at the highest temperature for 0.5h, it is naturally cooled to room temperature to obtain a full-body ceramic tile prepared by recycling large-particle waste porcelain.

[0068] In the embodiment of the present invention, the waste porcelain is obtained by crushing the waste of building ceramics and sanitary ceramics with a sintering temperature in the range of 1160-1220°C, and the tap density of the large particles of 4-5 mesh waste porcelain is 1.3-1.4 g / cm 3 The tap density of 40-80 mesh fine waste porcelain is 1.5-1.6 g / cm 3 The tap density of the calcined material is 0.8-0.9 g / cm 3The particle size of 3 mol% yttrium stabilized zirconia is 1 to 2 μm, and the colorant is cobalt blue material for ceramic body decoration.

[0069] The whole ceramic tile prepared in the embodiment of the present invention is as follows Figure 3 Its performance indicators are shown in Table 1.

[0070] Table 1 Performance indicators of full-body ceramic tiles prepared in the embodiments of the present invention

[0071]

Claims

1. A method for recycling large particles of waste porcelain to prepare full-body ceramic tiles, characterized in that The following steps are involved: (1) Preparation of calcined material 60-70 parts of potassium feldspar, 10-20 parts of calcite and 10-20 parts of magnesite powder are dry mixed according to weight proportions, and the obtained mixture is calcined at 900-1000° C., and sifted to obtain a calcined material; (2) Preparation of blanks (2-1) dry-mixing 10 to 20 parts of a calcined material, 1 to 3 parts of 3 mol% yttrium-stabilized zirconia, and 0 to 5 parts of a body colorant according to weight proportions to obtain a body reinforcement material; (2-2) adding 50-60 parts of large-particle waste porcelain with a particle size of 4-5 mesh and 20-30 parts of fine-particle waste porcelain with a particle size of 40-80 mesh to the green body reinforcement material and continuing dry mixing to obtain a mixed material; (2-3) adding a 0.5 wt % hydroxypropyl methylcellulose aqueous solution to the mixture by spraying, wherein the amount is 8 to 12 wt % of the mixture, and stirring and aging to obtain a blank; (3) Vibration compaction molding The blank is poured into a vibration molding machine, and vibration compaction molding is performed according to the process parameters of vibration frequency 5-15 Hz, exciting force 6000-6500 N, static pressure 1300-1800 N, and compaction time 5-15 s to obtain a green blank with a thickness of 12-15 mm; (4) Drying and calcination The green body is dried and placed in a kiln, heated to 1200-1240°C at a rate of 20°C / min, kept at the highest temperature for 0.5-1h, and then naturally cooled to room temperature to obtain a full-body ceramic tile prepared by recycling large-particle waste porcelain.

2. The method for preparing full-body ceramic tiles by recycling large-particle waste porcelain according to claim 1, characterized in that: The main crystalline phase of the green body strengthening material in step (2-1) is Zr 0.963 Y 0.037 O 1.982 , the amorphous phase content is greater than 85%, the initial melting temperature of the green body reinforcement material is 1160-1180°C, and the shrinkage rate of the sintered body at 1250°C is less than 2%.

3. The method for recycling large-particle waste porcelain to prepare full-body ceramic tiles according to claim 1, characterized in that: The waste porcelain is obtained by crushing the waste of building ceramics and sanitary ceramics with a sintering temperature within the range of 1160-1220°C. The tap density of the large particles of 4-5 mesh waste porcelain is 1.3-1.4 g / cm 3 The tap density of 40-80 mesh fine waste porcelain is 1.5-1.6 g / cm 3 The tap density of the calcined material is 0.8 to 0.9 g / cm 3 .

4. The method for recycling large-particle waste porcelain to prepare full-body ceramic tiles according to claim 1, characterized in that: The particle size of the 3 mol % yttrium stabilized zirconia is 1-2 μm.

5. The method for recycling large-particle waste porcelain to prepare full-body ceramic tiles according to claim 1, characterized in that: The colorants used for the blank are praseodymium yellow, cobalt blue and chrome green.

6. The method for recycling large-particle waste porcelain to prepare full-body ceramic tiles according to claim 1, characterized in that: In the step (1), the calcined material has a sieve residue of less than 0.2% after passing through a 200-mesh screen; the dry mixing time is 0.5 to 1 hour; the stirring time in the step (2-3) is 0.5 to 1 hour, and the aging time is 3 to 5 days; the porosity of the green body in the step (3) is less than 0.5%.

7. A product obtained by using the method for preparing full-body ceramic tiles by recycling large-particle waste porcelain as described in any one of claims 1 to 6.

8. The product according to claim 7, characterized in that: The flexural strength of the full-body ceramic tile prepared by recycling the large-particle waste porcelain is greater than 30MPa and the water absorption rate is less than 0.5%.

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