A kind of chromite roasting rotary kiln working layer castable and preparation method thereof

Abstract

The invention relates to a chromite-roasting rotary kiln operation layer pouring material and a preparation method thereof. According to the technical scheme, the preparation method comprises the following steps: taking 35-40wt% of titanium-iron slag particles and 25-30wt% of brown aluminum oxide particles as aggregate materials, and taking 20-25wt% of titanium-iron slag fine powder, 6-11wt% of rho-Al2O3 micropowder and 1-3wt% of yttrium oxide micropowder as matrix materials; preparing materials according to the components and the contents of the aggregate materials and the matrix materials, firstly mixing the matrix materials uniformly, then adding the uniformly mixed matrix materials into the aggregate materials, and uniformly mixing; then adding silica sol accounting for 8-10wt% of the sum of the matrix materials and the aggregate materials, uniformly stirring, vibrating and molding, curing for 6-12 hours under the room-temperature condition, and finally keeping the temperature for 12-24 hours under the condition at the temperature of 90-110 DEG C to prepare the chromite-roasting rotary kiln operation layer pouring material. The preparation method of the chromite-roasting rotary kiln operation layer pouring material has the characteristics of low cost and simple process; the prepared chromite-roasting rotary kiln operation layer pouring material is low in heat conductivity coefficient, high in cold-state compression strength and high in slag erosion resistance.

Description

technical field [0001] The invention belongs to the technical field of castables for the working layer of a roasting rotary kiln. In particular, it relates to a casting material for the working layer of a chromite roasting rotary kiln and a preparation method thereof. Background technique [0002] Chromite ore is an important raw material for smelting ferrochrome alloys and preparing chromium carbide and chromium salts. However, the composition of chromite ore is complex and its grade fluctuates greatly. Generally, rotary kilns are used to roast chromite ore. It is easy to form a large number of low-melt phases, causing serious erosion to the working layer of the rotary kiln; at the same time, the shell of the rotary kiln is prone to deformation due to thermal stress and mechanical stress (Chen Yongan, et al. "Chromium re-oxidation in the later stage of chromite roasting Mechanism", "Journal of Nonferrous Metals of China", 2015, 25(1): pp203~210), and then put forward stric...

AI Technical Summary

Problems solved by technology

High-aluminum-composite-phase castables / preforms are used as the working layer of the chromite roasting rotary kiln. Although the thermal conductivity is small and the high-temperature mechanical properties are excellent, the high-alumina-composite-phase castables / preforms are due to thermal expansion during high-temperature service. Unbalanced coefficient matching is easy to form a large number of microcracks, which in turn reduces the material's ability to resist slag erosion