Metallurgical performance and structural characteristics of cokes of hypercoal prepared from the mixture of low-rank coal and biomass residue

This study aimed to effectively utilize low-rank coal and biomass residue in the coking process. Hypercoal was produced through co-thermal extraction, and its performance as a component in the coking process was investigated. The effects of the amount of hypercoal extracted from 80 wt% low-rank coal and 20 wt% biomass residue on the coke strength and structure were investigated. Raman spectroscopy, optical microscopy, and scanning electron microscopy were used to analyze the carbonaceous, optical, and pore structures of the hypercoal coke. The optimal ratio of the coal blend contained 15 wt% hypercoal, with compressive and drum strengths of 7.76 MPa and 86 %, respectively. The vitrinite content and average maximum vitrinite reflectance of the hypercoal were 95 % and 0.352, respectively. High vitrinite contents in hypercoal contribute to the formation of mosaics within the coke, which can improve its cold strength. Moreover, the evolution of the hypercoal coke structure at various addition ratios was explored.