A PROCESS AND PLANT FOR THE PREPARATION OF ALKALINE CHROMATES FROM CHROMIUM MINERALS

摘要

The present invention relates to the production of alkaline chromates from chromium minerals. The ground minerals are mixed finely with alkali. Then the mixture is continuously fed into a rotating reactor (1) positioned in a heating chamber (5) and heated to a temperature of between 500 DEG and 1500 DEG C. Simultaneously the mixture is fed through (4) with one or more oxidation gases containing oxygen with known, pre-established and adjustable composition in order to oxidize the trivalent chromium compounds in a controlled environment. The oxidized mixture is conveyed through means (3) and is then leached.