The energy cost of pelletizing process has become higher than that of sintering process after the first and second oil crisis. In order to solve this problem, the following improvements were made on:
(1) The firing system of indurating process has been changed into the pulverized coal injection from oil and coke oven gas injection.
(2) The coke breeze has been inserted into the green pellets.
(3) The modification for the grate process and process fan has been carried out.
As the result of these improvements, the energy cost has become almost equal to sintering process. Also, for the improvement of shape character, crushed pellets have been developed. The operation test was carried out with this new pellets in Kakogawa No. 2 BF, and the successful result was obtained.
