A method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln

Abstract

The present invention provides a method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln. The method comprises the following steps: spraying an infrared radiation material composed of (La 0.36 Ce 0.64 )PO4 and Al(H2PO4)3 on the inner cavity of the shuttle kiln, the kiln door, the kiln car and the surface of the refractory material of the sagger, and obtaining a shuttle kiln with infrared radiation function after high-temperature burning; using natural gas combustion as the heat source for the decomposition reaction of lanthanum cerium carbonate to prepare qualified lanthanum cerium oxide powder. The present invention significantly enhances the infrared radiation emissivity in the shuttle kiln, improves the temperature field intensity and uniformity in the kiln. It is very easy to spray the infrared radiation material for both newly built and existing shuttle kilns. The infrared radiation shuttle kiln can significantly reduce natural gas consumption by burning lanthanum cerium oxide, and has practical application value in industrial production.

Description

Technical Field

[0001] The present invention relates to the field of refractory materials, and in particular to a method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln. Background Art

[0002] Lanthanum cerium oxide has a very wide range of application fields and can be used as polishing powder, catalyst, hydrogen storage material, glass ceramics, PVC additive, rare earth alloy, etc. In 2021, the output of lanthanum cerium oxide in China was 173,200 tons. According to different application fields, the required lanthanum cerium compounds are also different. Lanthanum cerium compounds are mainly sold as products such as lanthanum cerium oxide, lanthanum cerium carbonate, and lanthanum cerium chloride.

[0003] At present, rare earth separation enterprises use burning equipment such as tunnel kilns, shuttle kilns, rotary kilns, and suspension kilns. Among them, tunnel kilns include roller kilns, trolley tunnel kilns, and pusher kilns. The components and particle sizes of cerium oxide products burned in rotary kilns and suspension kilns are uniform. Roller kilns and trolley tunnel kilns are suitable for large-scale and continuous production. At present, these several types of burning kilns have been widely used in enterprises; while shuttle kilns have great flexibility and can meet the intermittent production of small batches and multi-variety special performance products. Shuttle kilns belong to intermittent kilns. The operation cycle from heating, heat preservation to cooling is relatively long. The heat storage loss and heat dissipation loss of the kiln are large, the flue gas temperature is high, and the energy consumption is relatively large. However, in rare earth separation enterprises, it is an essential burning equipment for cultivating and developing new products.

[0004] The energy source of the shuttle kiln is natural gas. Natural gas furnaces have the advantages of environmental protection, high energy efficiency, and high maximum temperature. The method of burning lanthanum cerium oxide in a shuttle kiln is to generate high-temperature hot flue gas by burning natural gas through high-speed burners. The high-speed burners can uniformly heat the lanthanum cerium carbonate in the kiln, ensuring the quality of the burned lanthanum cerium oxide products and improving the heat transfer rate. The burners are installed on both side walls of the kiln. After the hot flue gas enters the shuttle kiln, it flows from the gaps between the two sides of the kiln car and the kiln wall to the top of the kiln, and then flows downward through the gaps between the saggars on the kiln car under the action of the chimney draft. It heats the lanthanum cerium carbonate in the saggars from top to bottom. According to the "dispersed vertical air flow rule", the temperature in the shuttle kiln is relatively uniform. The hot flue gas transfers heat to the lanthanum cerium carbonate in the saggars on the kiln car. Even at high temperature stages, the role of convective heat transfer is very large.

[0005] The heat generated by the shuttle kiln mainly heats lanthanum cerium carbonate through convection and radiation. The higher the temperature, the greater the proportion of radiative heat transfer. Especially when the temperature is above 800 °C, the proportion of radiative heat transfer reaches more than 80%. Therefore, improving the efficiency of radiative heat transfer is crucial for energy conservation in high-temperature firing kilns. In industrial production, especially when the shuttle kiln is filled with lanthanum cerium carbonate, the raw materials near the edge of the shuttle kiln decompose preferentially during the firing process, while the lanthanum cerium carbonate in the middle of the shuttle kiln needs to stay in the heat preservation section for a certain period of time to fully react. This results in larger particles of lanthanum cerium oxide near the edge of the shuttle kiln compared to the middle area, and even overburning occurs, causing inconsistent particle sizes of lanthanum cerium oxide powder at different positions in the same shuttle kiln. Temperature control in the lanthanum cerium oxide firing kiln plays a key role in product quality. The amount of lanthanum cerium carbonate loaded in the shuttle kiln is relatively large, and it takes a long time for heat to transfer to the middle part of the shuttle kiln, resulting in slower decomposition of lanthanum cerium carbonate in the middle part of the shuttle kiln. Only by increasing the firing temperature and prolonging the heat preservation time can the complete decomposition of cerium carbonate in the middle part be achieved, which increases the consumption of natural gas. Summary of the Invention

[0006] In view of this, the present invention aims to provide a method for reducing natural gas consumption in the firing of lanthanum cerium oxide in a shuttle kiln to reduce energy consumption during the firing of lanthanum cerium oxide.

[0007] To achieve the above object, the technical solution of the present invention is realized as follows:

[0008] A method for reducing natural gas consumption in the firing of lanthanum cerium oxide in a shuttle kiln, the method comprising the following steps:

[0009] 1) Spray an infrared radiation material on the inner cavity, kiln door, kiln car and refractory surface of the shuttle kiln, and obtain a shuttle kiln with infrared radiation function after high-temperature firing; wherein, the infrared radiation material is composed of 100 - 200 parts by weight of (La 0.36 Ce 0.64 )PO4 and 180 - 200 parts of an Al(H2PO4)3 solution with a solid content of 48% - 58%.

[0010] 2) Load lanthanum cerium carbonate into an infrared radiation shuttle kiln, evenly place it on a kiln car with infrared radiation on the surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating, heat preservation and cooling, lanthanum cerium oxide powder is obtained.

[0011] Wherein the total rare earth content REO is greater than 99%, and the ignition loss is less than 0.5%.

[0012] Further, the infrared radiation material is prepared by the following method:

[0013] 1) Mix (La0.36 Ce 0.64 )PO4 and a dispersant are added to water and dispersed at high speed. The mass ratio of powder to water is (1 - 2):1. The amount of the dispersant is 1‰ - 5‰ of the total amount of the slurry. The rotation speed is 800 - 1000 r / min. After complete dispersion, the slurry is transferred to a sand mill for sanding until the particle size D (90) ≤10.0 μm;

[0014] 2) Transfer the sanded slurry to a disperser, add an Al(H2PO4)3 solution, and stir to obtain an infrared radiation material.

[0015] Furthermore, the dispersant is one or a mixture of two or more of BYK190, RT - 8040, and RT - 8022.

[0016] Furthermore, in step 1), before spraying the infrared radiation material, first remove refractory mud and dust from the inner cavity of the shuttle kiln, the kiln door, the kiln car, and the surface of the refractory of the sagger. After spraying, dry at room temperature and heat up according to the drying procedure of the shuttle kiln. The maximum temperature reaches 1300°C and is kept warm for 2 h to obtain a shuttle kiln with infrared radiation function.

[0017] Furthermore, in step 2), the maximum temperature is controlled at 950°C - 1050°C. When the temperature in the kiln drops to 500°C, pull out the kiln car. When the temperature of the sagger and lanthanum cerium oxide on the kiln car drops below 100°C, discharge the material.

[0018] Furthermore, the spraying thickness of the coating is 0.2 - 0.4 mm.

[0019] Compared with a conventional shuttle kiln, the infrared radiation shuttle kiln of the present invention shortens the heating - up time by more than 20%, shortens the heat - preservation time by more than 30%, increases the cooling - down time by more than 30%, and reduces the natural - gas consumption per ton of lanthanum cerium oxide by more than 25%.

[0020] The full - wavelength integral emissivity of the infrared radiation material is greater than 0.93. Spraying the infrared radiation material significantly enhances the radiative heat transfer of the shuttle kiln, and also improves the temperature field intensity and uniformity in the kiln. The far - infrared rays emitted by the radiation material directly penetrate into the interior of lanthanum cerium carbonate for heating, enabling the lanthanum cerium carbonate at the edge and in the middle of the sagger to synchronously remove free water and crystal water, and the lanthanum cerium carbonate to synchronously decompose to release carbon dioxide, thus shortening the heating - up time. The radiation material (La 0.36 Ce 0.64 )PO4 has a higher emissivity above 1000°C, which is beneficial to the rapid and complete decomposition of lanthanum cerium carbonate into lanthanum cerium oxide during the heat - preservation process, shortening the heat - preservation time. During the cooling - down process, although the natural - gas combustion heating stops, the temperature in the kiln is very high, and the radiation material still has a high far - infrared emissivity, slowing down the cooling speed and extending the cooling - down time.

[0021] Compared with the prior art, the method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln according to the present invention has the following advantages:

[0022] (1) The present invention significantly enhances the infrared radiation emissivity in the shuttle kiln, improves the temperature field intensity and uniformity in the kiln, and reduces the natural gas consumption per ton of lanthanum cerium oxide by more than 25% compared with a conventional shuttle kiln of the same model.

[0023] (2) The far-infrared rays emitted by the infrared radiation material of the present invention directly penetrate into the interior of lanthanum cerium carbonate for heating, enhance the energy of the decomposition reaction of lanthanum cerium carbonate in the middle part of the sagger, promote the accelerated decomposition of lanthanum cerium carbonate in the middle part, significantly shorten the heating and heat preservation time, and the particle size distribution of the lanthanum cerium oxide powder in the sagger is uniform, solving the problem that the particles of the lanthanum cerium oxide powder near the edge of the sagger are larger and even overburned.

[0024] (3) The infrared radiation material is sprayed on the surface of the refractory material in the shuttle kiln. After high-temperature calcination, it reacts with the substrate to form a dense glaze surface, which has high-temperature stability, blocks the outward diffusion of impurities in the refractory material at high temperature, reduces the pollution of lanthanum cerium oxide, and solves the problem of non-rare earth impurity pollution in the lanthanum cerium oxide burning process; at the same time, the infrared radiation material has the same elements as the burning material and does not affect the purity of the lanthanum cerium oxide product.

[0025] (4) The infrared radiation material of the present invention has high stability in high-temperature, reducing and oxidizing environments, preventing the corrosion of the kiln body by the gas generated by the decomposition of lanthanum cerium carbonate, and extending the service life of the shuttle kiln;

[0026] (5) The high-temperature binder Al(H2PO4)3 in the infrared radiation material of the present invention generates meta-aluminum phosphate after high-temperature calcination, which is a chain-like structure of phosphorus-oxygen tetrahedrons, can effectively bear and transfer loads, has excellent cementing properties, and can firmly bond (La 0.36 Ce 0.64 )PO4 and the refractory material to make the material a whole, and form a layer of glaze on the surface of the refractory material. The highest burning temperature of lanthanum cerium oxide is lower than the firing temperature of the infrared radiation shuttle kiln, and aluminum and phosphorus will not enter the lanthanum cerium oxide, ensuring the purity of the lanthanum cerium oxide product.

[0027] (6) (La 0.36 Ce 0.64 )PO4 in the infrared radiation material of the present invention has a very high infrared radiation emissivity, improves the uniform heating of lanthanum cerium carbonate in the shuttle kiln, and the analysis data of the ignition loss of the lanthanum cerium oxide product in each crucible in the kiln is similar and the particle size distribution is uniform. Detailed implementation manners

[0028] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0029] The present invention will be described in detail below in conjunction with embodiments.

[0030] Example 1

[0031] A method for reducing natural gas consumption in the firing of lanthanum cerium oxide in a shuttle kiln, the method comprising the following steps:

[0032] (1) Infrared radiation shuttle kiln: In a shuttle kiln with an inner cavity volume of 10 M 3 , remove refractory mud and dust from the inner cavity, kiln door, kiln car and surface of the refractory of the sagger of the shuttle kiln, spray an infrared radiation material on the surface of the refractory, with a spraying thickness of 0.3 mm. After drying at room temperature, heat it up according to the drying procedure of the shuttle kiln, and keep the temperature at 1300 °C for 2 h to obtain a shuttle kiln with infrared radiation function, and the full-wavelength integrated emissivity is greater than 0.93 within the working temperature range;

[0033] The preparation method of the infrared radiation material is as follows: Add 200 parts of (La 0.36 Ce 0.64 )PO4 and 0.6 parts of dispersant BYK190 into 100 parts of water and disperse at high speed. The powder-water ratio is 2:1, the amount of the dispersant is 2‰ of the total amount of the slurry, and the dispersion speed is 1000 r / min. Transfer the dispersed slurry to a sand mill for sanding until the particle size D (90) ≤10.0 μm; then transfer the sanded slurry to a disperser, and add 200 parts of an Al(H2PO4)3 solution with a solid content of 50% to obtain an infrared radiation coating;

[0034] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation sagger, evenly place it on the kiln car with infrared radiation on the surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, keeping warm and cooling down, the highest temperature is controlled at 950 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the sagger and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder, with the total rare earth content REO in the powder being greater than 99% and the ignition loss being less than 0.5%;

[0035] (3) Comparative analysis of natural gas consumption: Compared with a conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 22.5%, shortens the heat preservation time by 32.5%, increases the cooling-down time by 33%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 28.38%.

[0036] Example 2

[0037] A method for reducing natural gas consumption in the firing of lanthanum cerium oxide in a shuttle kiln, the method comprising the following steps:

[0038] (1) Infrared radiation shuttle kiln: In a shuttle kiln with an inner cavity volume of 10M 3 of the shuttle kiln, remove refractory mud and dust from the inner cavity of the shuttle kiln, the kiln door, the kiln car, and the surface of the refractory of the sagger. Spray infrared radiation material on the surface of the refractory, with a spraying thickness of 0.3 mm. After drying at room temperature, heat it up according to the drying procedure of the shuttle kiln, and keep the temperature at 1300 °C for 2 h to obtain a shuttle kiln with infrared radiation function, and the full-wavelength integral emissivity is greater than 0.92 within the working temperature range;

[0039] The preparation method of the infrared radiation material is as follows: Add 100 parts of (La 0.36 Ce 0.64 )PO4 and 0.4 parts of dispersant BYK190 into 100 parts of water and disperse at high speed. The powder-water ratio is 1:1, the amount of the dispersant is 2‰ of the total amount of the slurry, the dispersion speed is 1000 r / min, and the dispersed slurry is transferred to a sand mill for sanding until the particle size D (90) ≤10.0 μm; then transfer the sanded slurry to a disperser and add 200 parts of an Al(H2PO4)3 solution with a solid content of 50% to prepare an infrared radiation coating;

[0040] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation sagger, evenly place it on a kiln car with infrared radiation on the surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, keeping warm, and cooling down, the maximum temperature is controlled at 1000 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the sagger and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder, and the total rare earth content REO in the powder is greater than 99%, and the ignition loss is less than 0.5%;

[0041] (3) Comparative analysis of natural gas consumption: Compared with the conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 20%, shortens the heat preservation time by 30%, increases the cooling-down time by 30%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 25.95%.

[0042] Example 3

[0043] A method for reducing natural gas consumption in burning lanthanum cerium oxide in a shuttle kiln, the method comprising the following steps:

[0044] (1) Infrared radiation shuttle kiln: In a shuttle kiln with an inner cavity volume of 10M 3In a shuttle kiln, remove refractory mud and dust from the inner cavity of the shuttle kiln, the kiln door, the kiln car, and the surface of the refractory of the sagger. Spray an infrared radiation material on the surface of the refractory with a spraying thickness of 0.3 mm. After drying at room temperature, heat it up according to the drying procedure of the shuttle kiln, and keep the temperature at 1300 °C for 2 h to obtain a shuttle kiln with infrared radiation function, and the total wavelength integrated emissivity is greater than 0.94 within the working temperature range;

[0045] The preparation method of the infrared radiation material is as follows: Add 150 parts of (La 0.36 Ce 0.64 )PO4 and 1.25 parts of dispersant BYK190 into 100 parts of water and disperse at high speed. The powder-to-water ratio is 3:2, the amount of the dispersant is 5‰ of the total amount of the slurry, the dispersion speed is 1000 r / min, and the dispersed slurry is transferred to a sand mill for sanding until the particle size D (90) ≤10.0 μm; Then transfer the sanded slurry to a disperser and add 180 parts of an Al(H2PO4)3 solution with a solid content of 50% to obtain an infrared radiation coating;

[0046] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation sagger, evenly place it on a kiln car with infrared radiation on the surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, keeping warm, and cooling down, the maximum temperature is controlled at 1050 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the sagger and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder, and the total rare earth content REO in the powder is greater than 99%, and the ignition loss is less than 0.5%;

[0047] (3) Comparative analysis of natural gas consumption: Compared with a conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 25%, shortens the heat preservation time by 35%, increases the cooling-down time by 35%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 30.88%.

[0048] Comparative Example 1

[0049] On the basis of Example 1 above, in step (1), the preparation method of the infrared radiation material is: Add 200 parts of (La 0.36 Ce 0.64 )PO4 and 2 parts of dispersant BYK190 into 800 parts of water and disperse at high speed. The powder-to-water ratio is 1:4, the amount of the dispersant is 2‰ of the total amount of the slurry, the dispersion speed is 1000 r / min, and the dispersed slurry is transferred to a sand mill for sanding until the particle size D (90)≤10.0 μm. Then transfer the ground slurry to a disperser, add 200 parts of Al(H2PO4)3 solution to prepare an infrared radiation coating; obtain a shuttle kiln with infrared radiation function, and the full-wavelength integrated emissivity is greater than 0.86 within the working temperature range;

[0050] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation sagger, evenly place it on a kiln car with infrared radiation on the surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, holding the temperature and cooling down, the maximum temperature is controlled at 950 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the sagger and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder. The total rare earth content REO in the powder is greater than 99%, and the ignition loss is less than 0.5%;

[0051] (3) Comparative analysis of natural gas consumption: Compared with the conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 15.5%, shortens the heat-preservation time by 17.2%, increases the cooling-down time by 16.8%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 16.88%.

[0052] Comparative Example 2

[0053] Based on the above Example 1, in step (1), the preparation method of the infrared radiation material is as follows: Add 200 parts of (La 0.36 Ce 0.64 )PO4 and 0.6 part of dispersant BYK190 to 100 parts of water for high-speed dispersion. The powder-to-water ratio is 2:1, the amount of the dispersant is 2‰ of the total slurry amount, the dispersion speed is 1000 r / min. After complete dispersion, transfer the slurry to a sand mill for grinding until the particle size D (90) ≤10.0 μm. Then transfer the ground slurry to a disperser, add 300 parts of Al(H2PO4)3 solution to prepare an infrared radiation coating; obtain a shuttle kiln with infrared radiation function, and the full-wavelength integrated emissivity is greater than 0.87 within the working temperature range;

[0054] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation crucible, evenly place it on a kiln car with infrared radiation on its surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source. The natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, heat preservation and cooling down, the maximum temperature is controlled at 950 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the crucible and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder. The total rare earth content REO in the powder is greater than 99%, and the ignition loss is less than 0.5%;

[0055] (3) Comparative analysis of natural gas consumption: Compared with the conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 16.5%, shortens the heat preservation time by 18.0%, increases the cooling-down time by 18.0%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 17.6%.

[0056] Comparative Example 3

[0057] On the basis of the above-mentioned Example 1, in step (1), the preparation method of the infrared radiation material is as follows: Add 200 parts of (La 0.36 Ce 0.64 )PO4 and 0.6 part of dispersant BYK190 into 100 parts of water for high-speed dispersion. The powder-to-water ratio is 2:1. The amount of the dispersant is 2‰ of the total amount of the slurry. The dispersion speed is 1000 r / min. Transfer the completely dispersed slurry to a sand mill for sanding until the particle size D (90) ≤10.0 μm. Then transfer the sanded slurry to a disperser and add 200 parts of silica sol with a solid content of 30% to prepare an infrared radiation coating; obtain a shuttle kiln with infrared radiation function, and the full-wavelength integral emissivity is greater than 0.88 within the working temperature range;

[0058] (2) Preparation of lanthanum cerium oxide: Load lanthanum cerium carbonate into an infrared radiation crucible, evenly place it on a kiln car with infrared radiation on its surface, the kiln car enters the infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source. The natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of lanthanum cerium carbonate. Through the processes of heating up, heat preservation and cooling down, the maximum temperature is controlled at 950 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the crucible and lanthanum cerium oxide on the kiln car drops below 100 °C, discharge the material to obtain qualified lanthanum cerium oxide powder. The total rare earth content REO in the powder is greater than 99%, and the ignition loss is less than 0.5%;

[0059] (3) Comparative analysis of natural gas consumption: Compared with the conventional shuttle kiln, the infrared radiation shuttle kiln shortens the heating-up time by 17.0%, shortens the heat preservation time by 18.5%, increases the cooling-down time by 18.5%, and reduces the natural gas consumption per ton of lanthanum cerium oxide by 17.8%.

[0060] Table 1 Comparison of the results of Examples 1-3

[0061]

[0062]

[0063] Table 1 Comparison of the results of Comparative Examples 1-3

[0064]

[0065] It can be found through the above comparison that by adopting the method of the present invention, the natural gas consumption for burning lanthanum cerium oxide in a shuttle kiln can be significantly reduced. The heating-up time is shortened by more than 20%, the heat preservation time is shortened by more than 30%, and the natural gas consumption per ton of lanthanum cerium oxide is reduced by more than 25%. The infrared radiation material formula proposed by the present invention is the optimal formula. Changing the proportion and type of (La 0.36 Ce 0.64 )PO4 or the binder, the heating-up time for burning lanthanum cerium oxide in a shuttle kiln is shortened by < 20%, the heat preservation time is shortened by < 20%, and the natural gas consumption per ton of lanthanum cerium oxide is reduced by more than 20%. This is because, in the material formula proposed by the present invention, the binder Al(H2PO4)3 reacts with (La 0.36 Ce 0.64 )PO4 with a suitable ratio and the substrate at high temperature to generate a dense ceramic-phase and high-emissivity glaze layer, improving the reaction efficiency of lanthanum cerium oxide calcination, shortening the reaction time, and reducing the natural gas consumption.

[0066] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln, characterized in that: The method comprises the following steps: 1) Spray infrared radiation materials on the inner cavity of the shuttle kiln, the kiln door, the kiln car and the surface of the refractory materials of the sagger, and obtain a shuttle kiln with infrared radiation function after high-temperature burning; among them, the infrared radiation materials include 100-200 parts by weight of (La 0.36 Ce 0.64 )PO4 and 180-200 parts of an Al(H2PO4)3 solution with a solid content of 48% to 58%; 2) Load cerium lanthanum carbonate into an infrared radiation sagger, evenly place it on a kiln car with infrared radiation on its surface, the kiln car enters an infrared radiation shuttle kiln, close the kiln door and start heating up. Use natural gas as the energy source, and the natural gas burns through a high-speed burner to generate high-temperature hot flue gas for the decomposition reaction of cerium lanthanum carbonate. Through the processes of heating up, holding the temperature and cooling down, cerium lanthanum oxide powder is obtained; The infrared radiation material is prepared by the following method: 1) Add (La 0.36 Ce 0.64 )PO4 and a dispersant into water and disperse at high speed. The mass ratio of powder to water is (1 - 2):

1. The amount of the dispersant is 1‰ - 5‰ of the total amount of the slurry. The rotation speed is 800 - 1000 r / min. Transfer the completely dispersed slurry to a sand mill for sanding until the particle size D (90) ≤10.0 μm; 2) Transfer the sanded slurry to a disperser, add Al(H2PO4)3 solution, and stir to obtain the infrared radiation material.

2. The method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln according to claim 1, characterized in that: The dispersant is one or a mixture of two or more of BYK190, RT-8040, and RT-8022.

3. The method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln according to claim 1, wherein: In step 1), before spraying the infrared radiation material, first remove refractory mud and dust from the inner cavity of the shuttle kiln, the kiln door, the kiln car and the surface of the sagger refractory material. After spraying, dry at room temperature, heat up according to the drying procedure of the shuttle kiln, and keep the temperature at 1300 °C for 2 h to obtain a shuttle kiln with infrared radiation function.

4. The method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln according to claim 1, characterized in that: In step 2), the maximum temperature is controlled at 950 °C - 1050 °C. When the temperature in the kiln drops to 500 °C, pull out the kiln car. When the temperature of the sagger and cerium lanthanum oxide on the kiln car drops below 100 °C, discharge the material.

5. The method for reducing natural gas consumption by burning lanthanum cerium oxide in a shuttle kiln according to claim 1, characterized in that: The spraying thickness of the coating is 0.2 - 0.4 mm.

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