BASIC STUDY FOR APPLICATION OF DUPLEX PELLET TECHNOLOGY TO ROASTING OF TIBETAN CHROMITE WITH SODIUM-CARBONATE

In the roasting process of chromite, the problems such as aggregation of pellets or sticking to the wall cause the irregular operation of th e rotary kiln. In order to solve these problems, the duplex-pellet met hod was proposed for roasting of chromite ore. This pellet consists of core and shell. The shell is intended to play a role to prevent aggre gation or sticking by the addition of much residue of roast. The resid ue which is produced in leaching of the roast of chromite ore has a hi gher melting point than the conventional roast charge. In the present study, to research the basic problem of the duplex pellet technology, the conversion ratio of core and shell having various contents of resi due was measured and identification of roast by X-ray analysis was als o conducted. From these results, the appropriate compositions of core and shell were determined.