Light microporous thermal insulation castable and preparation method thereof

Abstract

The invention relates to a light microporous thermal insulation castable and a preparation method thereof. According to the invention, steady microporous foam is prepared and added into the castable, so that porosity of the castable can be improved and pores in the castable can be in micro-nano scale. 40-70wt% of light microporous particles are used as aggregate, and 10-15wt% of fine powder, 10-20wt% of micro powder and 10-25wt% of binding agent are used as matrix; moreover, microporous foam with steady bubbles, which accounts for 30-70v% of sum of aggregate and matrix, is added. The method provided by the invention guarantees the feature of larger critical particle size of the castable, and further introduces a lot of microporous foam, diameter of bubbles is not more than 0.1mm, the prepared light microporous thermal insulation castable has high porosity, high strength, low heat conductivity and good thermal shock resistant stability, and usage temperature of the castable is up to 1700 DEG C.

Description

technical field [0001] The invention belongs to the technical field of refractory materials. In particular, it relates to a lightweight microporous heat-insulating pouring material and a preparation method thereof. technical background [0002] Lightweight heat-insulating refractory castables refer to refractory castables with low thermal conductivity and low heat capacity, also known as thermal insulation refractory castables. Heat-insulating refractory castables mainly obtain low thermal conductivity by introducing pores. Generally speaking, the higher the porosity of the material, the lower the thermal conductivity, and the smaller the pore size, the lower the thermal conductivity of the material. the better. Insulating refractory materials are widely used in reducing energy consumption of high-temperature equipment and meeting special high-temperature process requirements. The problems of the existing method for preparing lightweight heat-insulating refractory castabl...

AI Technical Summary

Problems solved by technology

The problems of the existing method for preparing lightweight heat-insulating refractory castables are: first, the porosity is not high, and the main source of pores in refractory castables is lightweight aggregate, and the porosity of prepared lightweight castables is generally lower than that of light-weight castables. The porosity of the aggregate, so that the high porosity of the lightweight castable cannot be achieved; the second is that the porosity of the castable is high but the pore size is large. For porous materials, the smaller the pore diameter, the higher the strength of the lightweight material , the thermal conductivity is low, because the number of pores in the material with small pore diameter is large, which helps to reduce heat convection and radiation at high temperature and thus reduces the thermal conductivity of the castable

[0003] "A magnesium-aluminum spinel lightweight refractory castable and its preparation method (201310004655.1)" applied by the applicant introduces a foaming agent into the magnesium-aluminum spinel lightweight refractory castable, and realizes that in the matrix of the castable The introduction of air bubbles greatly increases the porosity of the castable, but since the bubbles are formed during the stirring of the castable, more large pores are formed in the matrix, although the thermal conductivity of the castable is reduced to a certain extent, However, if the micro-nano porosity in the matrix can be realized, the thermal conductivity of the castable will be further reduced and the strength will also be improved.