Three-layer composite brick and preparation method thereof

Abstract

The invention discloses a three-layer composite brick which has good abrasive resistance, high refractoriness, high structure strength and good heat preservation and heat insulation performances, and a preparation method of the three-layer composite brick. The fireproof and heat-insulating integral function of the composite brick is achieved, and the energy-saving effect of a rotary kiln is improved. The three-layer composite brick comprises a heavy work layer, a light heat-insulating layer and a transition layer, wherein the heavy work layer is prepared from a fireproof material as a raw material, the light heat-insulating layer is prepared from a fused hollow ball as a raw material, the transition layer is arranged between the heavy work layer and the light heat-insulating layer, and the transition layer is prepared from spinel or magnesium aluminum chromium or magnesium aluminum titanium or magnesium zirconium spinel as raw materials. As the transition layer is led to the three-layer composite brick disclosed by the invention, reaction between the heavy work layer and the light heat-insulating layer can be avoided, so that the product has a good refractory insulation effect under the condition of not shortening the service life of the materials, so as to play the roles in saving energy consumption, reducing material consumption and reducing the dosage of refractory materials of the rotary kiln, thus the service life of equipment can be effectively prolonged.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to a three-layer composite brick and a preparation method thereof. Background technique [0002] With the continuous emergence of new technologies in cement production, the main equipment of cement production is developing in a large-scale direction. Increasing output, improving quality, saving energy and reducing costs, and reducing costs have become the keys to increasing benefits in production management. Most of the existing refractory bricks and heat insulation bricks are made of a single material, and bricks with various properties need to be used together. If they are used in relatively stationary equipment, such as tunnel kilns and inverted flame kilns, they can meet the requirements. , but on some relative moving equipment, such as rotary kiln, it is difficult to meet the requirements when used together. Some manufacturers and research units have c...

AI Technical Summary

Problems solved by technology

Most of the existing refractory bricks and heat insulation bricks are made of a single material. When using them, bricks with various properties need to be used together. If they are used on relatively fixed equipment, such as tunnel kilns and downdraft kilns, they can meet the requirements. , but on some relatively moving equipment, such as a rotary kiln, it is difficult to meet the requirements when used together

Some manufacturers and research units have conducted research and research on this, and have introduced some composite bricks that combine heavy materials and light materials. However, due to the low structural strength of the light parts, they cannot meet the requirements for use, and the The light part is easy to react due to material problems, which affects product performance and use effect, so it has not been widely promoted, and heavy bricks are still the main ones

[0003] Taking the 10,000t / d rotary kiln of Conch Group as an example, spinel bricks are used in the front transition zone, and magnesia-chrome bricks are used in the firing zone. Due to the large thermal conductivity of spinel bricks in the front transition zone and magnesia-chrome bricks in the firing zone (≥ 2.7W / m·K), so that the temperature of the outer wall of the kiln shell is relatively high (about 380°C, and it can reach 420°C at high temperature), which will increase the heat dissipation of the kiln shell on the one hand, thereby increasing the heat consumption of clinker. It will cause an increase in the unit cost of clinker; on the other hand, it is very easy to cause the cylinder to expand due to heat, resulting in an increase in the temperature of the supporting wheel in the middle of the kiln, especially in the later period of use or in summer, which will bring great hidden dangers to the normal operation of the equipment.

The overheating of the cylinder increases the damage probability of mechanical equipment and accelerates the deformation of the cylinder, and the deformation of the cylinder accelerates the mechanical damage of the inner lining. The result is brick falling and kiln shutdown, which affects the operation rate of the cement rotary kiln

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