Grate-Rotary Kiln Pellet Technology of Chromite Concentrate and Study on Mass Balance Calculation

The grate-rotary kiln pellet process of chromite concentrate, which is not only complying with the chrome ore agglomeration process, but also meeting the development of grate-rotary kiln pelletizing technology, and is an effective mearsure of increasing use of high-carbon ferrochrome as well. In this work, aiming at study on grate-rotary kiln pellets of 0.3Mtpa chromite concentrate’s mass balance calculations, the results show when the material is in the specific surface area of 1700cm2/g, the compressive strength of 11 N per pellet, drop number of 5 times from 0.5m height and cracking temperature of 435°C are achieved, especially cracking temperature is higher than the highest temperature of grate DDD 400°C. Measuring and calculation of dehydration loss, ash content and bulk material loss, as well as reduction loss and oxidation loss of coke powder of the green pellet are achieved. The reduction degrees of FeO and Cr2O3 are 68.06% and 52.24% respectively, and comprehensive reduction degree is 58.52%. In this research, the mass balance table of payments of the grate-rotary kiln system is listed, and a detailed mass balance diagram is also obtained.