Magnesium aluminate spinel-silicon carbide-aluminum composite refractory material

Abstract

The invention belongs to the field of refractory materials, and relates to a magnesium aluminate spinel-silicon carbide-aluminum composite refractory material. The magnesium aluminate spinel-silicon carbide-aluminum composite refractory material comprises aggregate and a matrix, wherein the aggregate comprises fused magnesia-alumina spinel particles and sintered magnesia-alumina spinel particles,and the addition amount of the fused magnesia-alumina spinel particles and the sintered magnesia-alumina spinel particles is 50-70% of the total amount of the raw materials; the matrix is silicon carbide, aluminum oxide and magnesium oxide; metal aluminum powder subjected to coating treatment is further added into the matrix, and the adding proportion is 2-8% of the total mass of the raw materials; and the aggregate, the matrix and a binding agent are uniformly mixed, undergo mechanical pressing molding, are dried, and then are sintered in a carbon-buried atmosphere to obtain the magnesium aluminate spinel-silicon carbide-aluminum composite refractory material. The high-temperature mechanical strength, the thermal shock stability and the coal cinder erosion resistance of the product are improved.

Description

technical field [0001] The invention belongs to the field of refractory materials, and mainly relates to a magnesium aluminum spinel-silicon carbide-aluminum composite refractory material. Background technique [0002] Coal-water slurry gasification technology is the mainstream coal gasification technology widely used at home and abroad in recent years; coal-water slurry gasification furnace is an important device in the field of coal gasification, using coal and water as the main raw materials to use coal-water slurry at high temperature and high pressure Combustion at ambient to produce gaseous H 2 , CO, CO 2 Advanced equipment such as chemical raw materials; while the operating temperature of the coal-water slurry gasifier is high, and the working environment is harsh. Under the high temperature environment and high furnace pressure, the continuous erosion of gas, liquid and solid phase substances leads Severe wear and peeling occurred, which restricted the normal opera...

AI Technical Summary

Problems solved by technology

The magnesium-aluminum spinel-silicon carbide composite refractory material has excellent corrosion resistance, but its high-temperature mechanical properties are poor (the high-temperature flexural strength is about 1-3 MPa under the condition of buried carbon at 1650 ° C). Under the harsh working environment, the material is prone to wear and peeling, and its excellent resistance to coal slag penetration and erosion cannot be reflected

The main reason for its low high-temperature mechanical strength is that in the atmosphere of buried carbon or nitrogen, the fine silicon carbide powder in the material matrix will still be partially oxidized to form SiO 2 , forming a glass phase with a low melting point. During high-temperature use, the glass phase changes from solid to liquid, which destroys the stability of the material matrix structure, resulting in its high-temperature mechanical strength being much lower than that at room temperature.