Method for forming and demoulding waste ceramic by grouting without firing

Abstract

The application provides a method for forming, demolding and baking-free of waste ceramic by grouting, wherein gypsum powder, water, porous filler, sepiolite fiber, water-based epoxy resin and tributyl phosphate are mixed and stirred uniformly in proportion to prepare gypsum slurry for preparing gypsum mold; then, treated ceramic waste, kaolin, water, toughening agent, dispersing agent, binder, cement and solidification agent AB are mixed and stirred uniformly in proportion to prepare mud slurry; finally, the mud slurry is poured into the gypsum mold, the mud slurry is fully contacted with the inner wall of the gypsum mold, and when the mud slurry is adsorbed to the required thickness, the excess mud slurry is poured out from the gypsum mold; the product blank is taken out from the gypsum mold after a certain period of time; and the product blank is finished and dried to obtain the formed product. The gypsum mold prepared by the method has good strength and water absorption performance, the blank formed by grouting in the gypsum mold has good strength, and is easy to demold.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of slip casting, in particular to a method for slip casting with waste ceramic and then demolding and firing-free. BACKGROUND

[0002] Slip casting, also known as casting, is based on the physical properties of porous gypsum mold that can absorb water. The ceramic powder is mixed into a slurry with fluidity, and then injected into a porous mold (mainly gypsum mold). The water is absorbed by the mold (gypsum mold), forming a uniform mud layer with a certain thickness. During the dehydration and drying process, a green body with certain strength is formed. This method is called slip casting.

[0003] The existing single-hole slip casting method uses a specific mold made of gypsum. The mold is filled with kaolin slurry with a water ratio of about 1:1. The gypsum mold absorbs water from the slurry, causing the kaolin in the slurry to naturally and uniformly adhere to the inner wall of the mold through crystallization. The excess slurry is poured out when the crystallized kaolin reaches the desired thickness. The mold is then removed after the mud layer in the mold forms a ceramic green body with certain strength after drying for a certain period of time. The quality of the ceramic green body formed by slip casting depends on the mold and the slurry. Therefore, the present application proposes a method for slip casting with waste ceramic and then demolding and firing-free. SUMMARY

[0004] To overcome the shortcomings of the prior art, the present application provides a method for slip casting with waste ceramic and then demolding and firing-free.

[0005] To achieve the above-mentioned purpose, the present application provides a method for slip casting with waste ceramic and then demolding and firing-free, which comprises the following steps:

[0006] Step 1), preparing a gypsum mold;

[0007] Mix and stir the gypsum powder, water, porous filler, sepiolite fiber, water-based epoxy resin, and tributyl phosphate in proportion to prepare a gypsum slurry. After filtration, the gypsum mold is obtained by pouring and shaping according to the product shape and drying.

[0008] Step 2), preparing a slurry;

[0009] Mix and stir the treated ceramic waste, kaolin, water, toughening agent, dispersant, cement binder, and solidification agent AB in proportion to prepare a slurry.

[0010] Step 3), slip casting;

[0011] After the gypsum mold obtained in step 1) is assembled, it is tied up with an oil core belt or a rubber belt, then the slurry obtained in step 2) is injected into the gypsum mold, the slurry is fully contacted with the inner wall of the gypsum mold, and is adsorbed to the required thickness, then the excess slurry is poured out from the gypsum mold; after standing for a certain time, the product blank is taken out from the gypsum mold; the product blank is finished and dried, and a shaped product is obtained.

[0012] By adopting the technical scheme, the porous filler added in the prepared gypsum mold can improve the strength and water absorption performance of the gypsum mold; the sepiolite fiber added and uniformly mixed with the gypsum powder and the porous filler further increases the strength of the gypsum mold; the water-based epoxy resin added can form an isolation layer on the surface of the porous filler, without affecting the water absorption performance of the gypsum mold, and the formed mud layer is isolated from the gypsum mold after the blank is formed, so that the formed blank is easy to demold; the tributyl phosphate added as a defoaming agent removes the excess bubbles in the gypsum slurry. The toughening agent added in the prepared slurry is uniformly mixed with the ceramic waste, kaolin and cement, so that the strength of the blank after shaping is increased; the dispersing agent added improves the fluidity of the slurry, so that the ceramic waste and the toughening agent are uniformly suspended in the solution, and a uniform mud layer is formed on the gypsum mold, and the blank after shaping is easy to demold; the solidification crystal AB agent and the binder added can firmly combine the toughening agent, the ceramic waste, the kaolin and the cement together, so that the strength of the blank after shaping is increased. Therefore, the prepared gypsum mold has good strength and water absorption performance, and the blank obtained by injecting the prepared slurry into the gypsum mold has good strength and is easy to demold.

[0013] As a further description of the method for forming and demolding after grouting by using waste ceramic, preferably, the gypsum mold comprises the following raw materials in parts by weight: 90-100 parts of gypsum powder, 55-70 parts of water, 5-8 parts of porous filler, 0.5-1 part of sepiolite fiber, 0.3-0.5 part of water-based epoxy resin, and 0.1-0.3 part of tributyl phosphate.

[0014] As a further description of the method for forming and demolding after grouting by using waste ceramic, preferably, the slurry comprises the following raw materials in parts by weight: 80-100 parts of ceramic waste, 30-40 parts of kaolin, 100-130 parts of water, 15-25 parts of toughening agent, 1-3 parts of dispersing agent and 1-3 parts of binder, 10-15 parts of cement, and 15-35 parts of solidification crystal AB agent.

[0015] As a further description of the method for forming and demolding after grouting by using waste ceramic, preferably, the porous filler is selected from one or more of zeolite powder, bentonite, kaolin and diatomite.

[0016] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, the binder comprises sepiolite powder, sodium hexametaphosphate, and one or more selected from sodium carboxymethyl cellulose, amino carboxymethyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone.

[0017] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, the dispersant is sodium tripolyphosphate and / or sodium polyacrylate.

[0018] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, the toughening agent is sepiolite fiber.

[0019] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, in step 2), before preparing the slurry, the ceramic waste is subjected to acid pickling treatment using 10%-20% acetic acid, and after drying, the ceramic waste is sieved through a 150-200 mesh sieve.

[0020] By using the above technical solution, the ceramic waste is pickled with 10% acetic acid, which can remove the oxide film on the surface of the ceramic waste, and the solid powder is obtained by drying and sieving, thereby improving the bonding force between the ceramic waste and other components.

[0021] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, in step 3), before injecting the slurry, the slurry is subjected to water bath heating treatment, and the heating temperature is 35-40°C.

[0022] By using the above technical solution, the viscosity of the slurry is reduced by heating the slurry, which can improve the water permeability of the green body and speed up the forming time. It is known from the prior art that the thickness of the slurry layer formed by the green body is proportional to the square root of the forming time.

[0023] As a further description of the method for forming and demolding the waste ceramic slurry without firing according to the present application, preferably, the porosity of the porous filler is 60-70%. More preferably, the particle size of the porous filler is 100-150 μm.

[0024] By using the above technical solution, in order to make the strength and water absorption of the gypsum mold better, the porosity of the added porous filler is 60-70%, and more preferably, a porosity of 65% is used.

[0025] The gypsum mold prepared by the method of the application is prepared from gypsum powder, water, porous filler, sepiolite fiber, water-based epoxy resin, and tributyl phosphate.

[0026] The slurry prepared by the method of the application is prepared from ceramic waste, water, sepiolite fiber, sodium tripolyphosphate, and sodium polyacrylate. The toughening agent added in the prepared slurry is uniformly mixed with the ceramic waste, kaolin, and cement to increase the strength of the formed body; the dispersant added in the slurry improves the fluidity of the slurry, so that the ceramic waste and the toughening agent are uniformly suspended in the solution and form a uniform mud layer on the gypsum mold, and the formed body is easy to demold; the solidification agent and the binder added in the slurry firmly bind the toughening agent, ceramic waste, kaolin, and cement together to increase the strength of the formed body.

[0027] Therefore, the gypsum mold prepared by the method of the application has good strength and water absorption performance, and the body formed by injecting the prepared slurry into the gypsum mold has good strength and is easy to demold. DETAILED DESCRIPTION

[0028] In order to further understand the structure, features and other purposes of the application, the preferred embodiments are described in detail as follows, and the described embodiments are only used to illustrate the technical solutions of the application, but not to limit the application.

[0029] Preparation of experimental materials:

[0030] The ceramic waste can be collected from various ceramic factories.

[0031] The gypsum powder is purchased from Shandong Xinding Biological Technology Co., Ltd.

[0032] The zeolite powder, bentonite, kaolin, diatomite, and sepiolite fiber are all purchased from Lingshou Huimao Mineral Product Processing Factory.

[0033] The water-based epoxy resin is purchased from Shandong Jingshun Chemical Co., Ltd.

[0034] The tributyl phosphate is purchased from Shanghai Jizhishe Chemical Technology Co., Ltd.

[0035] The sodium tripolyphosphate is purchased from Weifang Pengchuang Chemical Co., Ltd.

[0036] The sodium polyacrylate is purchased from Renqiu Pengyu Chemical Co., Ltd.

[0037] The sepiolite powder was purchased from Hebei Xin Xu Mineral Products Co., Ltd.

[0038] The sodium hexametaphosphate was purchased from Qingzhou Linghang Chemical Co., Ltd.

[0039] The sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose and polyethylene oxide were purchased from Weifang Suoyuan Boyue New Material Co., Ltd.

[0040] The amino carboxymethyl cellulose was purchased from Wen'an Changhong Cellulose Factory.

[0041] The ethyl cellulose was purchased from Shandong Weifang Litai Composite Material Co., Ltd.

[0042] The polyacrylamide was purchased from Henan Saike Environmental Protection Technology Co., Ltd.

[0043] The polyvinylpyrrolidone was purchased from Jinan Tian Tai Chemical Co., Ltd.

[0044] The curing agent AB was purchased from Fujian Huanqiu Yiyuan Environmental Protection Technology Co., Ltd. The curing agent AB can also be prepared according to the concrete curing agent formula and production process disclosed in the patent document with the authorized announcement number CN101955331A.

[0045] Example 1: A method for forming, grouting and demolding a waste ceramic without firing

[0046] Preparation of gypsum mold: 900 g of gypsum powder with an average particle size of 120 mesh, 550 g of water, 50 g of kaolin with a porosity of 60%, 5 g of sepiolite fiber, 3 g of water-based epoxy resin and 1 g of tributyl phosphate were mixed and stirred uniformly to prepare gypsum slurry. After filtration, the gypsum mold was obtained by pouring and shaping according to the product shape and drying.

[0047] Preparation of slurry: first, the ceramic waste was treated with acid washing, the acid washing treatment used 10% acetic acid, and after drying, it was sieved through a 150 mesh sieve. Then, 800 g of treated ceramic waste, 300 g of kaolin, 1000 g of water, 150 g of sepiolite fiber, 10 g of dispersant (including 5 g of sodium tripolyphosphate and 5 g of sodium polyacrylate), 10 g of binder (including 3 g of sepiolite powder, 3 g of sodium hexametaphosphate and 4 g of sodium carboxymethyl cellulose), 100 g of cement and 150 g of curing agent AB were mixed and stirred uniformly to prepare the slurry.

[0048] Slip casting: firstly, the mud is heated in water bath, the heating temperature is 35℃. Then, the gypsum mold is assembled and tied with oil core belt or rubber belt. Then, the mud with temperature of 35℃ is injected into the gypsum mold, so that the mud is fully contacted with the inner wall of the gypsum mold and adsorbed to the required thickness, and the excess mud is poured out from the gypsum mold. Finally, after standing for a certain time, the product blank is taken out from the gypsum mold, and the product blank is finished and dried, thereby obtaining the formed product. It is observed that the gypsum mold is not adhered when separated from the blank, the blank is easy to demold, has high integrity, and increases the yield of the blank.

[0049] It is known from the prior art that the thickness of the mud layer formed by the blank is proportional to the square root of the forming time. Therefore, the thickness of the mud layer formed by the mud in the gypsum mold is reduced or increased according to the need, and the time for standing and drying to take out the blank is also reduced or increased accordingly. In the embodiment, the thickness of the finally formed product blank is 3mm, and the forming time is 15 minutes.

[0050] The gypsum mold prepared by the method has good strength and water absorption performance, and the blank obtained by slip casting the prepared mud in the gypsum mold has good strength and is easy to demold.

[0051] Example 2: A method for slip casting and demolding of waste ceramic after firing

[0052] Preparation of gypsum mold: 950g of gypsum powder with average particle size of 130 mesh, 600g of water, 70g of kaolin with porosity of 65%, 8g of sepiolite fiber, 4g of water-based epoxy resin, and 2g of tributyl phosphate are uniformly mixed and stirred to prepare gypsum slurry; after filtration, the gypsum mold is obtained by pouring and forming according to the shape of the product and drying.

[0053] Preparation of mud: firstly, the ceramic waste is subjected to acid pickling treatment, the acid pickling treatment uses 15% acetic acid, and after drying, it is sieved through a 180 mesh sieve. Then, 900g of treated ceramic waste, 350g of kaolin, 1250g of water, 200g of sepiolite fiber, 20g of dispersant (including 10g of sodium tripolyphosphate and 10g of sodium polyacrylate), 20g of binder (including 6g of sepiolite powder, 6g of sodium hexametaphosphate carboxyl, and 8g of sodium carboxymethyl cellulose), 120g of cement, and 250g of curing agent AB are uniformly mixed and stirred to prepare the mud.

[0054] Slip casting: firstly, the mud is heated in water bath, the heating temperature is 38℃. Then, the gypsum mold is assembled and tied with oil core belt or rubber belt. Then, the mud with a temperature of 38℃ is injected into the gypsum mold, so that the mud is fully contacted with the inner wall of the gypsum mold and adsorbed to the required thickness, and the excess mud is poured out from the gypsum mold. Finally, after standing for a certain time, the product blank is taken out from the gypsum mold, and the product blank is finished and dried to obtain the formed product. It is observed that the gypsum mold is not sticky when separated from the blank, the blank is easy to demold, has high integrity, and increases the yield of the blank.

[0055] It is known from the prior art that the thickness of the blank mud layer is proportional to the square root of the molding time. Therefore, the thickness of the mud layer formed by the mud in the gypsum mold is reduced or increased according to the molding time, and the time for standing and drying to take out the blank is also reduced or increased. In the embodiment, the thickness of the final product blank is 3mm, and the molding time is 15 minutes.

[0056] The gypsum mold prepared by the method has good strength and water absorption performance, and the blank obtained by slip casting the prepared mud in the gypsum mold has good strength and is easy to demold.

[0057] Example 3: A method for slip casting and demolding of waste ceramics without firing

[0058] Preparation of gypsum mold: 1000g of gypsum powder with an average particle size of 140 mesh, 700g of water, 80g of kaolin with a porosity of 70%, 10g of sepiolite fiber, 5g of water-based epoxy resin, and 3g of tributyl phosphate are mixed and stirred uniformly to prepare gypsum slurry; after filtration, the gypsum mold is obtained by pouring and forming according to the shape of the product and drying.

[0059] Preparation of mud: firstly, the ceramic waste is subjected to acid pickling treatment, the acid pickling treatment uses 20% acetic acid, and after drying, it is sieved through a 200 mesh sieve. Then, 1000g of treated ceramic waste, 400g of kaolin, 1300g of water, 250g of sepiolite fiber, 30g of dispersant (including 15g of sodium tripolyphosphate and 15g of sodium polyacrylate), 30g of binder (including 9g of sepiolite powder, 9g of sodium hexametaphosphate carboxyl, and 12g of sodium carboxymethyl cellulose), 150g of cement, and 350g of curing agent AB are mixed and stirred uniformly to prepare the mud.

[0060] Slip casting: first, the slurry is heated in water bath, the heating temperature is 40℃. Then, the gypsum mold is assembled and tied with oil core belt or rubber belt. Then, the slurry with a temperature of 40℃ is injected into the gypsum mold, so that the slurry fully contacts with the inner wall of the gypsum mold and is adsorbed to the required thickness, and the excess slurry is poured out from the gypsum mold. Finally, after standing for a certain time, the product blank is taken out from the gypsum mold, and the product blank is finished and dried, thereby obtaining the formed product. It is observed that the gypsum mold is not adhered when separated from the blank, the blank is easy to demold, has high integrity, and increases the yield of the blank.

[0061] It is known from the prior art that the thickness of the blank mud layer is proportional to the square root of the forming time. Therefore, the thickness of the mud layer formed by the slurry in the gypsum mold is reduced or increased according to the required forming time, and the time for standing and drying to take out the blank is also reduced or increased accordingly. In this embodiment, the thickness of the finally formed product blank is 3mm, and the forming time is 15 minutes.

[0062] The gypsum mold prepared by the method has good strength and water absorption performance, and the blank obtained by slip casting the prepared slurry in the gypsum mold has good strength and is easy to demold.

[0063] Example 4:

[0064] In this embodiment 4, the method of example 2 is referred to, and the difference from example 2 is that the dispersing agent in the step of preparing the slurry is sodium tripolyphosphate 20g. See Table 1.

[0065] Example 5:

[0066] In this embodiment 5, the method of example 2 is referred to, and the difference from example 2 is that the dispersing agent in the step of preparing the slurry is sodium polyacrylate 20g. See Table 1.

[0067] Example 6:

[0068] In this embodiment 6, the method of example 2 is referred to, and the difference from example 2 is that the binder in the step of preparing the slurry is sepiolite powder 20g. See Table 1.

[0069] Example 7:

[0070] In this embodiment 7, the method of example 2 is referred to, and the difference from example 2 is that the binder in the step of preparing the slurry is sodium hexametaphosphate carboxyl 20g. See Table 1.

[0071] Example 8:

[0072] In this embodiment 8, the method of example 2 is referred to, and the difference from example 2 is that the binder in the step of preparing the slurry is sodium carboxymethyl cellulose 20g. See Table 1.

[0073] Example 9:

[0074] Example 9 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was polyethylene oxide 20 g. See Table 1.

[0075] Example 10:

[0076] Example 10 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was polyacrylamide 20 g. See Table 1.

[0077] Example 11:

[0078] Example 11 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was polyvinylpyrrolidone 20 g. See Table 1.

[0079] Example 12:

[0080] Example 12 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was sepiolite powder 10 g and sodium carboxymethylaluminate 10 g. See Table 1.

[0081] Example 13:

[0082] Example 13 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was sepiolite powder 10 g and sodium carboxymethylcellulose 10 g. See Table 1.

[0083] Example 14:

[0084] Example 14 refers to the method of Example 2, with the difference that in the step of preparing the slurry the binder was sodium carboxymethylcellulose 10 g and sodium carboxymethylaluminate 10 g. See Table 1. Comparative Example 1:

[0085] Comparative Example 1 refers to the method of Example 2, with the difference that in the step of preparing the gypsum mold no aqueous epoxy resin was added. See Table 1.

[0086] Comparative Example 2:

[0087] Comparative Example 2 refers to the method of Example 2, with the difference that in the step of preparing the gypsum mold no kaolin was added. See Table 1.

[0088] Comparative Example 3:

[0089] Comparative Example 3 refers to the method of Example 2, with the difference that in the step of preparing the gypsum mold no sepiolite fiber was added. See Table 1.

[0090] Comparative Example 4:

[0091] Comparative Example 4 refers to the method of Example 2, with the exception that no kaolin and sepiolite fibers were added in the step of preparing the gypsum mold. See Table 1.

[0092] Comparative Example 5:

[0093] Comparative Example 5 refers to the method of Example 2, with the exception that no sepiolite fibers were added in the step of preparing the slurry. See Table 1.

[0094] Comparative Example 6:

[0095] Comparative Example 6 refers to the method of Example 2, with the exception that no dispersing agent was added in the step of preparing the slurry. See Table 1.

[0096] Comparative Example 7:

[0097] Comparative Example 7 refers to the method of Example 2, with the exception that no binder was added in the step of preparing the slurry. See Table 1.

[0098] Comparative Example 8:

[0099] Comparative Example 8 refers to the method of Example 2, with the exception that no solidification agent B was added in the step of preparing the slurry. See Table 1.

[0100] Table 1

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107] Example 15: Performance Test Experiment:

[0108] 1. Test the performance of the prepared gypsum mold:

[0109] The dry strength and water absorption of the gypsum mold prepared in Examples 1-3 and Comparative Examples 1-4 were tested. The gypsum sample strength was determined according to GBT 1640-1992, Physical Property Test Method for Gypsum Powder for Ceramic Mold, and the water absorption was determined as follows: the gypsum strip test piece after the bending strength test was weighed (M1), then immersed in water (the water surface was about 1 cm higher than the upper end of the gypsum test piece), placed for 2 h, taken out, the excess water on the surface of the test piece was wiped off with a wet cloth, weighed (M2) and the water absorption was calculated, the calculation formula was as follows: A = (M2-M1) / M1*100%. The test results are shown in Table 2:

[0110] Table 2

[0111] Dry strength (Mpa) Water absorption (%) Example 1 8.17 32.40 Example 2 8.21 32.45 Example 3 8.35 32.48 Comparative Example 1 8.21 32.48 Comparative Example 2 7.55 31.94 Comparative Example 3 7.49 30.11 Comparative Example 4 7.03 29.71

[0112] From the data of the dry strength and water absorption of Examples 1-3 and Comparative Examples 1-4 in Table 2, it can be seen that:

[0113] In Comparative Example 1, no water-based epoxy resin was added in the preparation steps of the gypsum mold, which had no obvious effect on the strength and water absorption of the gypsum mold. However, it was observed that when the gypsum mold prepared in Comparative Example 1 was used for slip casting, the green body occasionally adhered to the gypsum mold when it was separated from the gypsum mold, which was not easy to demold. However, when the gypsum mold prepared in Examples 1-3 was used for slip casting, the green body was easy to demold. Since the water-based epoxy resin can form a barrier layer on the surface of the porous filler, it does not affect the water absorption of the gypsum mold, and the formed mud layer is isolated from the gypsum mold after the green body is formed, therefore, the addition of the water-based epoxy resin can make the formed green body easy to demold.

[0114] In Comparative Example 2, no kaolin was added in the preparation steps of the gypsum mold, and in Comparative Example 3, no sepiolite fiber was added in the preparation steps of the gypsum mold, which had an effect on the strength and water absorption of the gypsum mold. In Comparative Example 4, no kaolin and sepiolite fiber were added in the preparation steps of the gypsum mold, which had the greatest effect on the strength and water absorption of the gypsum mold. Therefore, kaolin can improve the strength and water absorption of the gypsum mold, sepiolite fiber can also improve the strength and water absorption of the gypsum mold, and the synergistic effect of kaolin and sepiolite fiber has a greater effect on the strength and water absorption of the gypsum mold.

[0115] 2, Effect of toughening agent (sepiolite fiber) on the formed green body:

[0116] The bending strength of the green body formed by the slurry prepared in Examples 1-3 and Comparative Example 5 was tested, and the bending strength of the formed green body was measured by a green body strength tester (brand, FCJMYQ, DPK-500 digital display electric green body bending strength tester). The test results are shown in Table 3:

[0117] Table 3

[0118] Flexural strength (Mpa) Example 1 4.3 Example 2 4.7 Example 3 4.9 Comparative Example 5 3.2

[0119] From the data of the flexural strength of Example 1-3 and Comparative Example 5 in Table 3, it can be seen that the flexural strength of the formed body is significantly reduced in Comparative Example 5 in which sepiolite fibers are not added in the step of preparing the slurry. Therefore, sepiolite fibers can be added to the slurry to increase the strength of the formed body.

[0120] 3, Effect of sodium tripolyphosphate and sodium polyacrylate on the performance of the prepared slurry:

[0121] Since both sodium tripolyphosphate and sodium polyacrylate are dispersants, they also have the effect of water-reducing agent. Therefore, the water-reducing rate and flexural strength of the formed body of the slurry prepared in Examples 1-5 and Comparative Example 6 were tested. The water-reducing rate of the ceramic slurry was tested according to GB / T8076-2008 "Concrete Admixtures", which refers to the ratio of the difference in water consumption between the original ceramic raw materials (i.e. without adding water-reducing agent) and the water consumption when the water-reducing agent is added to the same viscosity of the ceramic raw materials after mixing with water of the same mass. The flexural strength of the formed body was measured by a body strength tester (brand, FCJMYQ, DPK-500 digital display electric body flexural strength tester). The test results are shown in Table 4:

[0122] Table 4

[0123] Flexural strength (Mpa) Water reduction (%) Example 1 4.3 36.9 Example 2 4.7 37.5 Example 3 4.9 38.1 Example 4 4.5 37.3 Example 5 4.4 37.0 Comparative Example 6 3.8 27

[0124] From the data of the flexural strength and water-reducing rate of Example 1-5 and Comparative Example 6 in Table 4, it can be seen that:

[0125] In Comparative Example 6, no dispersant (sodium tripolyphosphate and sodium polyacrylate) is added in the step of preparing the slurry, and both the flexural strength and water-reducing rate of the formed body are significantly reduced, with the greatest impact on the water-reducing rate.

[0126] In Examples 1-3, both sodium tripolyphosphate and sodium polyacrylate are added, while in Example 4, only one kind of sodium tripolyphosphate is added, and in Example 5, only one kind of sodium polyacrylate is added. The flexural strength and water-reducing rate of the formed body obtained in Examples 4-5 are significantly less than those of the formed body obtained in Examples 1-3.

[0127] In addition, it is observed that in Comparative Example 6, the formed body occasionally sticks to the gypsum mold or has uneven thickness when the gypsum mold is separated from the formed body, which is not easy to demold.

[0128] Therefore, sodium tripolyphosphate and sodium polyacrylate have the effects of increasing water-reducing and increasing strength, which can make the formed body easy to demold.

[0129] 4. Test the effect of the binder on the properties of the prepared slurry:

[0130] The flexural strength of the green bodies formed from the slurry prepared in Examples 6-14 and Comparative Example 7 was tested. The flexural strength of the formed green bodies was measured using a green strength tester (brand, FCJMYQ, DPK-500 digital display electric green strength tester). The test results are shown in Table 5:

[0131] Table 5

[0132] Flexural strength (Mpa) Example 6 4.2 Example 7 4.3 Example 8 4.5 Example 9 4.2 Example 10 4.5 Example 11 4.4 Example 12 4.3 Example 13 4.5 Example 14 4.6 Comparative Example 7 3.8

[0133] From the flexural strength data of Examples 6-14 and Comparative Example 7 in Table 5, it can be seen that:

[0134] Comparative Example 7, which did not add a binder during the preparation of the slurry, had a significantly reduced flexural strength of the formed green bodies. Therefore, a binder can be added to the slurry to increase the strength of the formed green bodies.

[0135] 5. Test the effect of the solidification crystal AB agent on the properties of the prepared slurry:

[0136] The flexural strength of the green bodies formed from the slurry prepared in Examples 6-14 and Comparative Example 7 was tested. The flexural strength of the formed green bodies was measured using a green strength tester (brand, FCJMYQ, DPK-500 digital display electric green strength tester). The test results are shown in Table 6:

[0137] Table 6

[0138] Flexural strength (Mpa) Example 1 4.3 Example 2 4.7 Example 3 4.9 Comparative Example 8 Flexural strength (Mpa) Example 1 Example 2 Example 3 Comparative Example 8 3.7

[0139] From the flexural strength data of Examples 1-3 and Comparative Example 8 in Table 6, it can be seen that:

[0140] Comparative Example 8, which did not add a solidification crystal AB agent during the preparation of the slurry, had a significantly reduced flexural strength of the formed green bodies. Therefore, a solidification crystal AB agent can be added to the slurry to increase the strength of the formed green bodies.

[0141] It should be noted that the above summary and detailed description of the application are intended to demonstrate the practical application of the technical solutions provided by the present application, and should not be interpreted as limiting the scope of protection of the present application. Those skilled in the art can make various modifications, equivalent replacements or improvements within the spirit and principles of the present application. The scope of protection of the present application is subject to the appended claims.

Claims

1. A method for forming a green body using waste ceramic, characterized in that, The method comprises the following steps: Step 1), preparing a gypsum mold; Gypsum powder, water, porous filler, sepiolite fiber, water-based epoxy resin and tributyl phosphate are mixed and stirred uniformly in proportion to prepare gypsum slurry; after filtration, the gypsum slurry is cast into a gypsum mold according to the shape of the product, and the gypsum mold is obtained after drying; Step 2), preparing a slurry; The treated ceramic waste, kaolin, water, toughening agent, dispersing agent, binder, cement and solidification crystal AB agent are mixed and stirred uniformly in proportion to prepare a slurry; the toughening agent is sepiolite fiber; the dispersing agent is sodium tripolyphosphate and / or sodium polyacrylate; the binder comprises sepiolite powder, sodium hexametaphosphate and one or more selected from carboxymethyl cellulose sodium, aminocarboxymethyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose, polyethylene oxide, polyacrylamide and polyvinylpyrrolidone; Step 3), slurry injection molding; Before the slurry is injected, the slurry is subjected to water bath heating treatment, and the heating temperature is 35-40 DEG C; the gypsum mold obtained in step 1) is assembled and tightly bound with an oil core belt or a rubber belt, then the slurry obtained in step 2) is injected into the gypsum mold, the slurry is fully contacted with the inner wall of the gypsum mold, and when the slurry is adsorbed to the required thickness, the excess slurry is poured out from the gypsum mold; after standing for a certain time, the product blank is taken out from the gypsum mold; the product blank is finished and dried to obtain a molded product.

2. The method of claim 1, wherein, The gypsum mold comprises the following raw materials in parts by weight: gypsum powder 90-100 parts, water 55-70 parts, porous filler 5-8 parts, sepiolite fiber 0.5-1 part, water-based epoxy resin 0.3-0.5 part, and tributyl phosphate 0.1-0.3 part.

3. The method of claim 1, wherein, The slurry comprises the following raw materials in parts by weight: ceramic waste 80-100 parts, kaolin 30-40 parts, water 100-130 parts, toughening agent 15-25 parts, dispersing agent 1-3 parts, binder 1-3 parts, cement 10-15 parts, and solidification crystal AB agent 15-35 parts.

4. The method of claim 1 or 2, wherein, The porous filler is selected from one or more of zeolite powder, bentonite, kaolin and diatomite.

5. The method of claim 1, wherein, In step 2), before the slurry is prepared, the ceramic waste is subjected to pickling treatment, the pickling treatment adopts 10%-20% acetic acid, and after drying, the ceramic waste is sieved through a 150-200 mesh sieve.

6. The method of claim 1, wherein, The porosity of the porous filler is 60-70%.

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