Gas-phase reduction of iron and chrome from chromites

This paper focuses on studies of iron and partially chromium gas-phase reduction from chrome ore raw material of the Kempirsay Massif. The studies were carried out using a thermogravimetric method in a CO flow followed by chemical analysis of the samples. It is shown that: depending on the time of the samples exposure at the CO consumption rate 75 m³ / h and the temperature of 1200 ° C, basic reduction processes take place in the first 20 minutes of exposure; with temperature growth from 1000 to 1400 ° C and an exposure time of 20 minutes, the degree of Fe and Cr reduction from the considered samples increases from 13 to 37%. Gaseous reducing agent and low temperatures contribute to a greater reduction of iron rather than chromium. Gaseous CO is a good iron reducing agent (with a small excess it allows to obtain a high degree of iron reduction) and a weak chromium reducing agent (the degree of chromium reduction is 14% with the multiple excess of CO and on condition of the chromium carbides formation). (paper)