Abstract: With different reaction times,reaction temperatures,and addition amounts of filler (solid residue) and soda,the influencing trend of various factors on oxidation ratio of chromium were studied under different oxygen contents.Experimental results indicated that,oxygen content was an important factor and oxidation ratio of chromium could be improved with higher oxygen content.Proper oxygen content was about 40% (volume fraction);proper reaction temperature and time were 1 100 ℃ and 60 min respectively;the best amount of filler should be confirmed according to the highest chromium′s oxidation ratio of chromite and furnace burden threshold.Increasing addition of soda could raise oxidation ratio of chromium,but led to low utilization ratio of soda.Soda had obvious impact on oxidation ratio of chromium when usage rate was below 1.4.

Key words: chromite, lime free roasting, oxygen content, oxidation ratio