High purity andalusite brick for high blast temperature and long time type hot blast stove and preparation method thereof

Abstract

The invention discloses a high pure andalusite brick for an air heating furnace with high blast temperature and long service life, and a preparation method thereof. The high pure andalusite brick is prepared by the following steps: andalusite, sillimanite sand, activated alumina powder and kaolin are taken as raw materials, andalusite powder, the activated alumina powder and kaolin powder which have the raw material particle size of between 0.088 and 0 mm are premixed into powder first, then the remaining particle materials, sulphite liquor and the prepared powder are mixed evenly to produce pug, the produced pug is pressed into a green brick, and the green brick is transferred into a high-temperature tunnel kiln for calcination to obtain a product. As a refractory material of a large-scale air heating furnace, the product has low creep rate and good thermal shock stability during use, and can apparently improve the blast temperature and the service life of the air heating furnace, thereby saving a large amount of maintenance cost and energy-saving cost for iron and steel users, and obtaining remarkable social and economical benefits.

Description

1. Technical field: [0001] The invention relates to a refractory material used in a large-scale hot blast stove, in particular to a high-purity andalusite brick used in a large-scale high-blast-temperature, long-life hot-blast stove and a preparation method thereof. 2. Background technology: [0002] With the rapid development of the national economy, the demand for steel materials is increasing. The rapid growth of steel production in recent years is mainly due to the large-scale development of blast furnaces. The development of blast furnaces has also promoted the rapid development of the most important auxiliary thermal equipment of blast furnaces - hot blast stoves. Hot blast stoves are used as a regenerative heat exchange The device plays a very important role in achieving high production, low consumption and reducing the cost of pig iron in the blast furnace. [0003] In recent decades, hot blast stoves have gradually developed towards large-scale, high wind temperatu...

AI Technical Summary

Problems solved by technology

Because the main raw material used is calcined bauxite clinker, the large amount of impurities in it makes the material no longer suitable for the environment of high-temperature hot-blast stoves, and the creep resistance and thermal shock resistance are not up to the use of modern hot-blast stoves. Require

[0005] 2. Silica brick: This material is characterized by good creep resistance, but its thermal shock resistance is very poor, and it is only suitable for the spherical top part of the hot blast stove

Therefore, this material is not an ideal material in order to achieve a long life of more than 30 years in my country's high-wind-temperature hot-blast stoves.

[0006] 3. Mullite brick: This material is theoretically an ideal refractory material for hot blast stoves. However, due to the difference in the synthesis process of mullite raw materials, the quality of mullite bricks is very different.

The main raw material of this material is bauxite, which is made by adding part of andalusite. Due to the existence of a large amount of impurities in bauxite, the mullite transformed by andalusite is further decomposed, which seriously affects the performance of the product.

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