Method for quickly preparing low-heat-conduction mullite heat-insulation brick on basis of foam processes

Abstract

The invention discloses a method for quickly preparing a low-heat-conduction mullite heat-insulation bricks on the basis of foam processes. The method includes adding auxiliary materials including setting accelerators, water reducing agents, structural propping agents and water into raw materials including aluminum oxide fine powder, corundum fine powder, expansive agents, gel powder, clay, mullite powder and binding agents and mixing the auxiliary materials and the raw materials with one another to obtain first mixtures; adding foaming agents into the first mixtures and uniformly mixing the foaming agents and the first mixtures with one another to obtain second mixtures; calcining the second mixtures to obtain the low-heat-conduction mullite heat-insulation bricks. The invention further discloses the low-heat-conduction mullite heat-insulation brick prepared by the aid of the method. The method and the low-heat-conduction mullite heat-insulation brick have the advantages that the method includes simple preparation technologies and is free of environmental hazards, low in production cost and short in production cycle; good heat-insulation effects can be realized by the low-heat-conduction mullite heat-insulation brick prepared by the aid of the method, the low-heat-conduction mullite heat-insulation brick is high in thermal shock resistance, long in service life and wide in service range, and the like.

Description

Technical field [0001] The invention belongs to the technical field of heat-insulating refractory materials, and specifically relates to a method for quickly preparing low-thermal-conductivity mullite heat-insulating bricks based on a foam method. Background technique [0002] The energy saving of industrial furnaces has always been an important problem that needs to be solved urgently by large energy consumers such as metallurgy, machinery, chemical industry, etc. The use of lightweight thermal insulation materials with lower thermal conductivity as furnace lining is one of the effective ways to solve this problem. Lightweight thermal insulation materials mainly achieve lightweight and thermal insulation effects by making holes inside the material, and the shape and distribution of the pores in the material have a great impact on the thermal conductivity of the product. Studies have shown that when the porosity in the material is the same, the smaller the pore size and the highe...

AI Technical Summary

Problems solved by technology

The patented technology has deficiencies: (1) The combustion of polystyrene and sawdust will cause harm to the environment; (2) Polystyrene and sawdust, etc., are used as pore-forming agents, and there is inhomogeneity in the dispersion of raw materials. Both are large in size, and the pores formed are mostly through holes, which are difficult to be used in the preparation of ultra-low thermal conductivity refractory materials

But there are also the following disadvantages: (1) Alumina hollow spheres will consume a lot of electric energy during the preparation process; (2) The pore diameter is large, and the porosity is difficult to further reduce, so its thermal insulation performance is affected

However, there are two problems with this technical solution: (1) Although microwave drying can be used to dry quickly, it is easy to cause cracking of large-sized samples, and at the same time, mass production requires high drying equipment, resulting in a significant increase in production costs; (2) ) The green strength of the product is extremely low, and it is not easy to handle without high temperature drying; (3) The product strength is too high, its thermal shock resistance is poor, and it is not easy to process

However, the current foam method has problems such as long drying cycle, easy cracking and low green strength, which restrict its large-scale application in the production of heat-insulating refractory materials.