High-strength high thermal-shock-resistance low-aluminium mullite brick

Abstract

The invention relates to a high-strength high thermal-shock-resistance low-aluminium mullite brick, which comprises the following components in percentage by weight: 15-50% of raw material sintered mullite, 5-15% of electric melted mullite, 10-40% of superfine flint clay, 10-30% of sillimanite, 10-30% of andalusite, 2-10% of activated alumina, 2-15% of zirconite, 2-12% of silica and 3-10% of bond clay. The high-strength high thermal-shock-resistance low-aluminium mullite brick provided by the invention made from the above raw material components has the advantages of high refractoriness under load (larger than or equal to 1500 DEG C) and heated volume stability, high thermal-shock resistance (larger than or equal to 50 times under water cooling at 1100 DEG C), low creep rate (smaller than or equal to 0.15 in 20-50 hours), good compressive strength (larger than or equal to 70Mpa), good volume stability and low impurity content at high temperature and the like; and at the same time, the CO corrosion resistance of the product provided by the invention is unaffected, so that the product provided by the invention can meet the use requirements of the medium and large blast furnace hot blast stove and other high-temperature kilns.

Description

technical field [0001] The invention relates to an unshaped refractory material, in particular to a high-strength, high-thermal-shock low-alumina mullite brick. Background technique [0002] At present, the refractory materials used in the medium and low temperature areas of large and medium-sized blast furnace hot blast stoves are mostly clay large wall bricks and checker bricks. Due to the low strength (not greater than 50Mpa) and low thermal shock stability of clay wall bricks and checker bricks, the thermal shock stability is less than 10 times. , high-temperature creep rate index fluctuations, and high content of impurities such as ferric oxide and potassium oxide, etc., which cause the phenomenon of settlement deformation, wall peeling and collapse of the hot blast stove during the application process, resulting in a generation of furnace life. The design life of more than 25 years cannot be reached; at present, some furnaces are deformed and collapsed after three to s...

AI Technical Summary

Problems solved by technology

[0002] At present, the refractory materials used in the medium and low temperature areas of large and medium-sized blast furnace hot blast stoves are mostly clay large wall bricks and checker bricks. Due to the low strength (not greater than 50Mpa) and low thermal shock stability of clay wall bricks and checker bricks, the thermal shock stability is less than 10 times. , high-temperature creep rate index fluctuations, and high content of impurities such as ferric oxide and potassium oxide, etc., which cause the phenomenon of settlement deformation, wall peeling and collapse of the hot blast stove during the application process, resulting in a generation of furnace life. The design life of more than 25 years cannot be reached; at present, some furnaces are deformed and collapsed after three to six months of operation, and some furnaces are between two to three to five years old, and have to be shut down for emergency repairs. It caused huge economic losses and cast a shadow over safe production.

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