Effect of Indian Medium Coking Coal on Coke Quality in Non-recovery Stamp Charged Coke Oven

The maximum possibility of utilizing the Indian coking coals and inferior grade coking coal for producing metalurgical coke through non Grecovery stamp charging technology was investigated. Indian indigenous coals contained low percent of vitrinite (<50%) and higher content of ash (> 15%) compared to imported coking coal. Therefore, the selection of appropriate proportion of diferent types of coals was a major chalenge for coke makers. Coal blend selection criterion based on a single coeficient, named as composite coking potential (CCP), was develG oped. The use of increased proportion of semisoft coal (crucible sweling number of 2. 5) and high ash (≥15%) indigenous coal in the range of 20%–35% and 20%–65% respectively in the blends resulted in good quality of coke. Plant data of a nonGrecovery coke oven were used for developing and validating the model. The results showed that the coke strength after reaction (CSR) varied in the range of 63.7%–67.7% and the M40 value was between 81.8 and 89.3 in both the cases.