Preparation process of low-energy-consumption earthen jar

Abstract

The present application belongs to the field of pottery jars, and aims to solve the problem of high energy consumption of kilns in high humidity areas, which relies on drying kilns and preheating zones for drying semi-finished products, and provides a low-energy-consumption pottery jar preparation process, which includes drying products using the waste heat of the firing section and cooling section of the kiln; the temperature of the kiln firing section is 1100-1200 DEG C; a heat extraction pipeline is arranged above the kiln firing section and cooling section, and a fan is arranged in the heat extraction pipeline; a cold water pipe is arranged below the kiln cooling section, and the water temperature at the outlet of the cold water pipe is 80-90 DEG C; the heat extraction pipeline and the outlet of the cold water pipe are both connected to the kiln drying section. By increasing the temperature of the drying kiln, the water content of the pottery jar before loading into the kiln can be relaxed, thereby promoting the completion of the drying stage of the formed wet embryo in a high humidity area, reducing the energy consumption of the drying stage, avoiding the defect of product corner dropping solved by the heating stage of the kiln, and increasing the efficiency of the preheating section.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of pottery jars, in particular, to a preparation process of a low-energy-consumption pottery jar. BACKGROUND

[0002] Pottery jars are traditional containers, usually made of clay, through processes such as molding, drying and firing. The preparation of pottery jars usually needs to go through processes such as material selection, embryo preparation, finishing and decoration, drying and firing. Generally, the drying of wet embryos basically relies on kiln waste heat and ambient temperature to achieve the purpose of drying semi-finished products. However, in areas with high humidity, such as Sichuan and Chongqing, the drying of semi-finished products is difficult to meet the requirements for kiln loading, and therefore, the drying kiln and the preheating zone of the kiln are needed to achieve the purpose of drying semi-finished products, resulting in a delay in the firing time of the kiln, especially the extension of the firing time at low temperature, and a high energy consumption. SUMMARY

[0003] The purpose of the present application is to provide a preparation process of a low-energy-consumption pottery jar, solving the problem of high energy consumption of the kiln due to the need for drying kiln and preheating zone for drying semi-finished products in areas with high humidity.

[0004] The embodiments of the present application are implemented by the following technical solutions:

[0005] A preparation process of a low-energy-consumption pottery jar, comprising drying products by using the waste heat of the firing section and the cooling section of the kiln; the temperature of the firing section of the kiln is 1100-1200℃; an air extraction pipeline is arranged above the firing section and the cooling section of the kiln, and a fan is arranged in the air extraction pipeline; a cold water pipeline is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipeline is 80-90℃; the outlet of the air extraction pipeline and the outlet of the cold water pipeline are both connected to the drying kiln of the kiln.

[0006] In the prior art, after the wet embryo is molded, it needs to be preliminarily dried before being loaded into the kiln. Generally, the moisture content of the wet embryo is reduced from 20% to below 5% during the preliminary drying stage, especially the moisture content of the thick bottom of the pottery jar is reduced to below 5%, so that the pottery jar can be dried by the drying kiln and then loaded into the kiln without defects such as corner dropping. If the production conditions of the factory cannot meet the above requirements, the temperature rising stage of the kiln needs to be extended to achieve the above purpose. Therefore, the applicant thinks how to improve the lower limit of the moisture content of 5% to make the process more suitable for the environment with high humidity. The present application first increases the drying temperature of the drying kiln of the kiln, which not only can completely dry the high-moisture area of the bottom corner of the pottery jar to the extent of 1%, but also can widen the moisture content of the pottery jar before loading into the kiln to the extent of 7-8% according to experiments, and the drying by the drying kiln can also achieve the purpose of reducing the moisture content of the pottery jar to below 1% before loading into the kiln. In this way, the preheating zone of the kiln from 100℃ to 400℃ can be heated at a normal speed without too much delay. The preheating section is followed by the firing section and the cooling section.

[0007] In order to avoid the temperature of the drying kiln being too high, the present application comprehensively considers the heat dissipation of the kiln body, the flue gas in the kiln and the recycling of the waste heat in the cooling section, and uses the aforementioned waste heat for drying the shaped wet embryo, so as to reduce the humidity of the wet embryo before entering the drying kiln.

[0008] Preferably, the power of the fan is 35kw-40kw, and the inner diameter of the heat extraction pipeline is 400mm-600mm.

[0009] By controlling the power and the pipe diameter, the amount and speed of the drying air can be regulated. Proper amount and speed of the drying air can effectively carry away the moisture on the surface of the wet embryo, accelerate the evaporation speed, and thus improve the overall drying efficiency. If the speed is too low, the humidity in the air is not easy to be carried away, which leads to a slow drying process. If the speed is too high, the surface may dry too fast, forming a hard shell that hinders the diffusion of internal moisture. Reasonable amount and speed of the drying air help to ensure uniform dehydration of the product during the drying process, avoid quality problems such as cracking and deformation, and are crucial for maintaining the integrity and aesthetics of the product.

[0010] Preferably, after the hot air in the heat extraction pipelines in the firing section and the cooling section of the kiln is converged, it is connected to the drying kiln of the kiln. The ratio of the hot air flow in the heat extraction pipeline in the firing section to the hot air flow in the heat extraction pipeline in the cooling section is 1: (2-4).

[0011] The present application recycles multiple types of waste heat, and different waste heat enters the drying area at different positions, some at the upper part and some at the lower part, so that the heat contacted by different parts of the product may differ. If the difference is too large, it is easy to cause defects in the appearance of the product. Therefore, the present application regulates the air volume of the heat extraction pipelines in different sections, so that when the temperature after convergence and the hot water from the outlet of the cold water pipeline are matched, the form stability of the product can be ensured.

[0012] Preferably, the drying temperature of the kiln is 110℃-150℃; and the water content of the bottom corner of the pottery jar after it is taken out of the kiln is not higher than 1%.

[0013] Preferably, the water content of the pottery jar before being put into the kiln is 7wt%-8wt%.

[0014] Due to the increase of the temperature of the drying kiln, the water content of the bottom corner of the pottery jar can be not higher than 1%, and thus the water content of the pottery jar before being put into the kiln can be relaxed to 7%-8%. The energy consumption required in the drying stage is reduced.

[0015] For most pottery enterprises, most of them use knife pressure forming rolling method at present, limited by equipment cost, changing into mechanical rolling, the cost is very high, most of the enterprises are difficult to bear, and it does not have the universality of industrial implementation. The applicant changes the existing knife pressure equipment into mechanical rolling method, the cost investment is relatively low, so the wet blank can use hard mud, the water content can be reduced from the source, the wet blank density is improved, the drying process is shortened, and the knife pressure process can use hard wood material, the back of the knife is strengthened with carbon steel, the iron ring rotates with the model during the rolling process, the knife is fixed, and the gap between the knife and the model is filled with mud and extruded to the top of the cylinder port to complete the rolling process; the mechanical rolling is to change the knife into a circular nylon roller which can rotate, since the iron ring with the model also rotates, the rolling time will be shortened, and the strength of the mud blank will be improved, and harder mud can also be used, but the knife pressure cannot roll the harder mud.

[0016] Preferably, the raw material used in the pottery contains 8wt%-12wt% of tile granules and 5wt%-6wt% of iron; the particle size of the tile granules ranges from 16 mesh to 120 mesh, and the tile granules with a particle size of 16 mesh-80 mesh account for 70wt%-85wt% of the total amount of tile granules.

[0017] The problem of black core and insufficient oxidation in the high temperature stage of the firing zone during the rapid firing of pottery is solved. Pottery cannot be rapidly fired, which is the second reason for the large gas consumption.

[0018] The pottery clay currently used by the applicant has the characteristics of good plasticity and high drying strength, contains 5%-6% of iron content, and is purple after firing, contains other impurities during high temperature stage. Such high iron content and high temperature volatile impurities also cause easy oxidation deficiency, insufficient oxidation will lead to more ferrous oxide, black color, high temperature mixed impurities, insufficient oxidation of mixed iron, local thickness of the part, and other problems such as large package. This requires the kiln to prolong the oxidation stage time of the preheating zone high temperature stage, which has to be extended passively, resulting in increased gas consumption.

[0019] The applicant introduces tile granules with high temperature and air permeability in the raw material preparation process, which not only recycles waste pottery, reduces solid waste discharge, but also reduces the problem of gas consumption caused by insufficient oxidation.

[0020] Preferably, the air permeability of the tile granules is 15 mm / s-35 mm / s.

[0021] Low air permeability cannot effectively solve the problem of insufficient oxidation, but high air permeability will also lead to the reduction of the strength of the pottery, the deterioration of water resistance and thermal stability, and the influence on the shape stability of the pottery during the preparation process.

[0022] Preferably, the tile granules include 15-20 parts of 16-mesh granules, 30-50 parts of 40-mesh granules, 30-40 parts of 60-mesh granules, 10-15 parts of 100-mesh granules, and 10-15 parts of 120-mesh granules.

[0023] Different particle sizes can better fill together, reduce voids, and thus improve the density and uniformity of the clay. This helps to maintain shape stability during the forming process, reducing the risk of cracking or deformation. Large particles can provide structural support, increasing the overall strength of the material; while small particles can fill the gaps between large particles, forming a more compact structure, the combination of the two can significantly improve the mechanical strength and durability of the finished product. During the firing process, the interaction between large and small particles can help to relieve thermal stress caused by temperature changes. Fine particles help to evenly distribute heat, while coarse particles can resist expansion or contraction caused by local high temperatures, together improving the thermal stability of the product.

[0024] Preferably, the temperature reduction operation of the kiln cooling section of the pottery jar includes: first reducing the temperature to 600-700 DEG C at a rate of 300-400 DEG C / h, then reducing the temperature to 450-500 DEG C at a rate of 30-40 DEG C / h, and finally reducing the temperature to 200-300 DEG C by using cold and hot air; the temperature difference between the cold and hot air and the pottery jar is 100-120 DEG C.

[0025] For large pottery jars, the volume is large, the cylinder thickness is thick, the mouth is small, and the belly is large, resulting in poor heat dissipation effect in the kiln cooling section. In order to reduce the wind silk, the cold air cannot be directly blown onto the product, only the cooling time can be prolonged, the cylinder body is slowly cooled to reduce the temperature, resulting in long cooling time and low production efficiency. The embodiment improves the cooling efficiency and reduces the energy consumption under the premise of ensuring the structural strength and complete form of the product after firing. The first stage of cooling adopts rapid cooling, which does not cause the generation of wind silk even if the cooling speed of the cold air is extremely fast. The cooling time is shortened, and the rapid cooling also improves the toughness of the porcelain body and the rapid cooling and heating performance of the pottery jar. The second stage of cooling is a slow cooling stage, and the cooling speed is slow to avoid causing rapid cooling hair cracks. The fracture surface is shiny and easy to identify. In the foregoing cooling process, the rapid cooling and heating performance of the product is improved, so that the temperature difference limit value controlled by the three-stage cooling is increased. However, when the product is cooled to the temperature consistent with or close to the temperature of the cold and hot air, it can be placed in a normal temperature environment for cooling.

[0026] Preferably, the heat extraction pipeline of the cooling section is arranged in the first stage of cooling.

[0027] The first stage of cooling refers to the area where the product is cooled from the highest temperature to 600-700 DEG C.

[0028] The present application has at least the following beneficial effects:

[0029] The present application can relax the water content of the product before loading into the kiln by increasing the temperature of the drying kiln, and further can promote the completion of the drying stage of the formed wet embryo in a high humidity area, and reduce the energy consumption of the drying stage, avoid solving the defect of product corner drop through the kiln heating stage, the preheating section can be normally heated at a high speed, and the efficiency is improved; recycling and utilizing various waste heat and using the waste heat for drying the formed wet embryo can solve the problem that the water content of the product before loading into the kiln is difficult to reduce to the required value, and the utilization of waste heat can also reduce the energy consumption of the product drying. DETAILED DESCRIPTION

[0030] In order to make the purpose, method scheme and advantages of the embodiments of the present application more clear, the method scheme in the embodiments of the present application is described clearly and completely, obviously, the described embodiments are part of the embodiments of the present application, not all the embodiments.

[0031] Embodiment 1: A low-energy-consumption pottery jar preparation process, comprising drying the product by using the waste heat of the kiln firing section and the cooling section; the temperature of the kiln firing section is 1100℃; an air extraction pipeline is arranged above the kiln firing section and the cooling section, two air extraction pipelines are added to each tunnel kiln, and a fan is arranged in the air extraction pipeline; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 80℃; the air extraction pipeline and the outlet of the cold water pipe are both communicated with the kiln drying kiln; the power of the fan is 35kw, and the inner diameter of the air extraction pipeline is 400mm; the hot air in the air extraction pipeline in the kiln firing section and the cooling section is converged and then communicated to the kiln drying kiln; the hot air flow rate of the air extraction pipeline in the kiln firing section to the hot air flow rate of the air extraction pipeline in the cooling section is 1:2. The drying temperature of the kiln drying kiln is 110℃; after the pottery jar is taken out from the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%. The water content of the pottery jar before loading into the kiln is 7wt%. The cooling operation of the pottery jar in the cooling section of the kiln comprises: first cooling at a rate of 300℃ / h to 600℃, then cooling at a rate of 30℃ / h to 450℃, and finally cooling by cold and hot air to 200℃; the temperature difference between the cold and hot air and the pottery jar is 100℃. The air extraction pipeline of the cooling section is arranged in a cooling section.

[0032] Embodiment 2: A preparation process of low-energy-consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1200℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in each heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 90℃; the outlet of each heat extraction pipe and the outlet of the cold water pipe are both connected to the drying kiln of the kiln; the power of the fan is 40kw, and the inner diameter of the heat extraction pipe is 600mm; the hot air in the heat extraction pipes in the firing section and the cooling section of the kiln is converged and then connected to the drying kiln of the kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:4; the drying temperature of the drying kiln of the kiln is 150℃; after the pottery jar is taken out of the drying kiln of the kiln, the water content of the bottom corner of the pottery jar is not higher than 1%; the water content of the pottery jar before being put into the kiln is 8wt%; the cooling operation of the pottery jar in the cooling section of the kiln comprises the following steps: firstly, cooling at a rate of 400℃ / h to 700℃, then cooling at a rate of 40℃ / h to 500℃, and finally cooling by using cold and hot air to 300℃; the temperature difference between the cold and hot air and the pottery jar is 120℃; the heat extraction pipe of the cooling section is arranged in a cooling zone.

[0033] Embodiment 3: A preparation process of low-energy-consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in each heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the outlet of each heat extraction pipe and the outlet of the cold water pipe are both connected to the drying kiln of the kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipes in the firing section and the cooling section of the kiln is converged and then connected to the drying kiln of the kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8; the drying temperature of the drying kiln of the kiln is 120℃; after the pottery jar is taken out of the drying kiln of the kiln, the water content of the bottom corner of the pottery jar is not higher than 1%; the water content of the pottery jar before being put into the kiln is 7.6wt%; the cooling operation of the pottery jar in the cooling section of the kiln comprises the following steps: firstly, cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃; the heat extraction pipe of the cooling section is arranged in a cooling zone.

[0034] Embodiment 4: A preparation process of low-energy-consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in each heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the heat extraction pipes and the outlet of the cold water pipe are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipes in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8. The drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%. The water content of the pottery jar before being put into the kiln is 7.6wt%. The cooling operation of the pottery jar in the cooling section of the kiln comprises the following steps: first, cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃. The heat extraction pipe of the cooling section is arranged in a cooling zone.

[0035] The raw material used for the pottery jar contains 8wt% of tile granules and 5wt% of iron; the particle size range of the tile granules is 16-120 mesh. The air permeability of the tile granules is 15 mm / s. In terms of weight parts, the tile granules include 15 parts of 16-mesh granules, 30 parts of 40-mesh granules, 30 parts of 60-mesh granules, 10 parts of 100-mesh granules, and 10 parts of 120-mesh granules.

[0036] Embodiment 5: A preparation process of low-energy-consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in each heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the heat extraction pipes and the outlet of the cold water pipe are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipes in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8. The drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%. The water content of the pottery jar before being put into the kiln is 7.6wt%. The cooling operation of the pottery jar in the cooling section of the kiln comprises the following steps: first, cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃. The heat extraction pipe of the cooling section is arranged in a cooling zone.

[0037] The raw material used for the pottery jar contains 12wt% of tile granules and 6wt% of iron; the particle size range of the tile granules is 16-120 mesh. The air permeability of the tile granules is 35mm / s. In terms of weight parts, the tile granules include 20 parts of 16-mesh granules, 50 parts of 40-mesh granules, 40 parts of 60-mesh granules, 10 parts of 100-mesh granules, and 10 parts of 120-mesh granules.

[0038] Embodiment 6: A preparation process of low-energy-consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in each heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the heat extraction pipes and the outlet of the cold water pipe are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipes in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8. The drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%. The water content of the pottery jar before being put into the kiln is 7.6wt%. The cooling operation of the pottery jar in the cooling section of the kiln comprises the following steps: first, cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃. The heat extraction pipe of the cooling section is arranged in a cooling zone.

[0039] The raw material used for the pottery jar contains 10wt% of tile granules and 5.5wt% of iron; the particle size range of the tile granules is 16-120 mesh. The air permeability of the tile granules is 26mm / s. In terms of weight parts, the tile granules include 18 parts of 16-mesh granules, 40 parts of 40-mesh granules, 35 parts of 60-mesh granules, 12 parts of 100-mesh granules, and 12 parts of 120-mesh granules.

[0040] Comparative Example 1: A preparation process of a low-energy consumption pottery jar, comprising drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; a heat extraction pipeline is arranged above the firing section and the cooling section of the kiln, two heat extraction pipelines are added to each tunnel kiln, and a fan is arranged in the heat extraction pipeline; a 25-meter-long cold water pipeline with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipeline is 85℃; the heat extraction pipeline and the outlet of the cold water pipeline are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipeline is 500mm; the hot air in the heat extraction pipeline in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipeline in the firing section to the hot air flow rate of the heat extraction pipeline in the cooling section is 1:5. The drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%. The water content of the pottery jar before being loaded into the kiln is 7.6wt%. The cooling operation of the pottery jar in the cooling section of the kiln comprises: first cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling to 250℃ by using cold and hot air; the temperature difference between the cold and hot air and the pottery jar is 110℃. The heat extraction pipeline of the cooling section is arranged in a cooling zone.

[0041] The raw material used for the pottery jar contains 10wt% of tile granules and 5.5wt% of iron; the particle size range of the tile granules is 16-120 mesh. The air permeability of the tile granules is 26mm / s. In terms of weight parts, the tile granules include 18 parts of 16-mesh granules, 40 parts of 40-mesh granules, 35 parts of 60-mesh granules, 12 parts of 100-mesh granules, and 12 parts of 120-mesh granules.

[0042] Comparative Example 2: A preparation process of a low-energy consumption pottery jar, including drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in the heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the outlet of the heat extraction pipe and the outlet of the cold water pipe are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipe in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8; the drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%; the water content of the pottery jar before being loaded into the kiln is 7.6wt%; the cooling operation of the pottery jar in the cooling section of the kiln includes: first cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃; the heat extraction pipe of the cooling section is arranged in a cooling zone.

[0043] The raw material used for the pottery jar contains 5.5wt% of iron.

[0044] Comparative Example 3: A preparation process of a low-energy consumption pottery jar, including drying the product by using the waste heat of the firing section and the cooling section of a kiln; the temperature of the firing section of the kiln is 1180℃; heat extraction pipes are arranged above the firing section and the cooling section of the kiln, two heat extraction pipes are added to each tunnel kiln, and a fan is arranged in the heat extraction pipe; a 25-meter-long cold water pipe with an inner diameter of 89mm is arranged below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 85℃; the outlet of the heat extraction pipe and the outlet of the cold water pipe are both connected to the kiln drying kiln; the power of the fan is 37kw, and the inner diameter of the heat extraction pipe is 500mm; the hot air in the heat extraction pipe in the firing section and the cooling section of the kiln is converged and then connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:2.8; the drying temperature of the kiln drying kiln is 120℃; after the pottery jar is taken out of the kiln drying kiln, the water content of the bottom corner of the pottery jar is not higher than 1%; the water content of the pottery jar before being loaded into the kiln is 7.6wt%; the cooling operation of the pottery jar in the cooling section of the kiln includes: first cooling at a rate of 350℃ / h to 650℃, then cooling at a rate of 35℃ / h to 480℃, and finally cooling by using cold and hot air to 250℃; the temperature difference between the cold and hot air and the pottery jar is 110℃; the heat extraction pipe of the cooling section is arranged in a cooling zone.

[0045] The raw material for the pottery jar contains 10wt% of tile granules and 5.5wt% of iron; the particle size of the tile granules ranges from 16 mesh to 120 mesh. The air permeability of the tile granules is 40mm / s. In terms of weight parts, the tile granules include 18 parts of 16 mesh granules, 40 parts of 40 mesh granules, 35 parts of 60 mesh granules, 12 parts of 100 mesh granules, and 12 parts of 120 mesh granules.

[0046] Experiment

[0047] The pottery clay is Rongxian pottery clay, and its chemical composition includes 76.2% of silicon dioxide, 19.13% of aluminum trioxide, 5.5% of iron trioxide accounting for the iron content of the pottery clay, 2.25% of potassium oxide, 0.114% of sodium oxide, and 0.81 of magnesium oxide.

[0048] Test One: The pottery jars are prepared according to the preparation processes provided in Examples 1-6 and Comparative Examples 1-3. Examples 1-3 directly use Rongxian pottery clay, and the jar height is 2.5m. Then, the apparent quality of the pottery jars is detected. Among them, the pottery jars prepared according to the preparation processes provided in Examples 1-3 have no cracks, no bubbles, and no deformation. Comparative Examples 1-3 all have certain appearance defects. The yield rates are shown in Table One.

[0049] Table One

[0050] Example 1 Example 2 Example 3 Example 4 Example 5 Yield 94.7% 95.2% 96.4% 95.9% 98.4% Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Yield 99.3% 87.9% 71.6% 91.7%

[0051] From the test results of Examples 4-6, it can be seen that the yield rate of the pottery jars prepared according to the preparation processes provided in Examples 4-6 is high.

[0052] From the comparison between Comparative Examples 1-3 and Example 6, it can be seen that the ratio of the hot air flow of the heat extraction pipeline in the kiln firing section to the hot air flow of the heat extraction pipeline in the cooling section, the composition of the pottery clay, and the air permeability of the tile granules all affect the appearance quality of the product.

[0053] Test Two: The pottery jars are prepared according to the preparation processes provided in Examples 1-6 and Comparative Examples 1-3. Then, the performance of the pottery jars is detected. Each group is tested 5 times, and the average value is taken. The test results are shown in Table Two.

[0054] Table Two

[0055] Example 1 Example 2 Example 3 Example 4 Example 5 Flexural strength (MPa) 164.4 172.8 189.0 197.7 204.6 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Flexural strength (MPa) 215.8 190.5 181.6 194.8

[0056] From the test results of Examples 4-6, it can be seen that the pottery jars prepared according to the preparation processes provided in Examples 4-6 have good strength performance.

[0057] From the comparison of the comparative examples 1-3 and example 6, it can be seen that the ratio of the hot air flow of the heat extraction pipeline in the kiln firing section to the hot air flow of the heat extraction pipeline in the cooling section, the clay composition and the air permeability of the tile granules all significantly affect the mechanical properties of the product.

[0058] The preferred embodiments of the present application have been described above with the preferred embodiments, but the present application is not limited to the above examples and can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A manufacturing process for a low-energy ceramic jar, characterized in that, The process includes using waste heat from the firing and cooling sections of a kiln to dry the product; the temperature of the firing section of the kiln is 1100℃-1200℃; a heat extraction pipe is installed above the firing and cooling sections of the kiln, and a fan is installed on the heat extraction pipe; a cold water pipe is installed below the cooling section of the kiln, and the water temperature at the outlet of the cold water pipe is 80℃-90℃; the outlets of both the heat extraction pipe and the cold water pipe are connected to the kiln drying kiln. The power of the fan is 35kw-40kw, and the inner diameter of the heat extraction pipe is 400mm-600mm; The hot air in the heat extraction pipes of the kiln firing section and the cooling section converges and is connected to the kiln drying kiln; the ratio of the hot air flow rate of the heat extraction pipe in the kiln firing section to the hot air flow rate of the heat extraction pipe in the cooling section is 1:(2-4). The moisture content of the pottery jars before loading into the kiln was 7wt%-8wt%; The raw materials used in the ceramic jars contain 8wt%-12wt% tile granules and 5wt%-6wt% iron; the particle size of the tile granules ranges from 16 mesh to 120 mesh, of which 16 mesh-80 mesh tile granules account for 70wt%-85wt% of the total tile granules. The air permeability of the tile granules is 15 mm / s - 35 mm / s; The cooling operation of the ceramic jar in the kiln cooling section includes: first cooling it at 300℃ / h-400℃ / h to 600℃-700℃, then cooling it at 30℃ / h-40℃ / h to 450℃-500℃, and finally cooling it down to 200℃-300℃ using hot and cold air; the temperature difference between the hot and cold air and the ceramic jar is 100℃-120℃.

2. The preparation process according to claim 1, characterized in that, The drying temperature of the kiln is 110℃-150℃; after the pottery jars are taken out of the kiln, the moisture content at the bottom corner of the jars is no higher than 1%.

3. The preparation process according to claim 1, characterized in that, By weight, the tile granules include 15-20 parts of 16-mesh granules, 30-50 parts of 40-mesh granules, 30-40 parts of 60-mesh granules, 10-15 parts of 100-mesh granules, and 10-15 parts of 120-mesh granules.

4. The preparation process according to claim 1, characterized in that, The heat extraction pipe of the cooling section is located in a cooling zone.