Heat-insulation magnesium casting material and preparation method thereof

Abstract

The invention relates to a heat-insulation magnesium casting material and a preparation method thereof. The technical scheme is as follows: the preparation method comprises the following steps: evenly mixing 20-50 wt% of magnesite, 33-63 wt% of mesitite, 0.9-7 wt% of silicon dioxide fine powder, 0.1-2 wt% of sodium polyphosphate and 3-8 wt% of water, thereby obtaining the heat-insulation magnesium casting material. The magnesite is more than one of fused magnesite grains, sintered magnesite grains, fused magnesite fine powder and sintered magnesite fine powder. The invention has the advantages of abundant raw material storage and simple preparation technique; and the prepared heat-insulation magnesium casting material basically has no crack or peel phenomenon, has the advantages of low heat conductivity, high strength, strong alkaline dust and slag corrosion resistance, high melting point and strong alkaline solid and gas slag corrosion resistance, and is beneficial to energy saving and consumption reduction. The heat-insulation magnesium casting material provided by the invention is suitable for liners of high-temperature industrial kilns and containers.

Description

technical field [0001] The invention belongs to the technical field of heat-insulating magnesia refractories. In particular, it relates to a heat-insulating magnesium castable and a preparation method thereof. Background technique [0002] Energy saving and consumption reduction is one of the main contents of the current national science and technology development planning outline, and it is also an important issue faced by high temperature industry for a long time. Magnesium castables have a series of advantages such as good wear resistance, strong resistance to alkaline solid and gaseous slag erosion, large heat capacity and high strength, and can be used as lining materials for high-temperature industrial kilns and containers. [0003] The ingredients of existing magnesia castables are usually based on fused or sintered magnesia as the main raw material. The fused or sintered magnesia is either granules, fine powder, or a mixture of granules and fine powder. Water is a...

AI Technical Summary

Problems solved by technology

However, during the molding and maintenance process, the hydration of magnesia fine powder in magnesia castables will cause cracks on the surface of the material and even peeling off during subsequent use, resulting in damage to the material and unsatisfactory use results. This limits the promotion of magnesium castables

At the same time, in the preparation process of magnesia, no matter the method of electric melting or sintering is used, the demand for electricity and fuel is large, and the energy consumption is very high.

On the other hand, the bulk density of the magnesia castable prepared by the traditional method is relatively high, and the thermal conductivity of the material does not decrease much at high temperature, which is not conducive to reducing heat loss.