METHOD FOR MEASURING OXYGEN CONTENT COMBINING IRON OXIDE IN CHROMIUM ORE AND PRODUCTION OF REDUCED CHROMIUM PELLET

摘要

PURPOSE:To accurately measure oxygen content combined with iron oxide in chromium ore by reducing the chromium ore with carbon under neutral atmosphere, measuring variation of weights and compositions of beforehand and after reduction and calculating FeO and Fe2O3. CONSTITUTION:The suitable quantity of carbonic material is contained in pellet, which the chromium ore is used as raw material, and heated at high temp. such as about 1,200 deg.C under neutral atmosphere of N2, etc., to execute the reduction. The variations of weights and compositions of the chromium ore and carbon before and after this reduction are measured. From this measured value FeO and Fe2O3 are calculated. By this method, the oxygen content combining with the iron oxide in the chromium ore can be accurately measured. In accordance with this predicted oxygen content, the carbon content in blended raw material composing of the chromium ore, the carbonic material of coke, etc., and a binder is adjusted. This blended raw material is pelletized with a disk pelletizer 1. Green pellet obtd. in there is charged into a rotary kiln 4 through a preheater 2 and reduced. By this method, the reduced chromium ore pellet is obtd. with suitable carbonic material and the necessary calory.