The structural characteristics and gasification performance of cokes of modified coal extracted from the mixture of low-rank coal and biomass

Abstract

This study aimed to effectively utilize low-rank coal and biomass residue in the coking process. The gasification performance of cokes prepared from the modified coal was investigated, meanwhile the structural characteristics of different cokes were analyzed by Raman spectroscopy, X-ray diffraction and infrared spectroscopy. The results showed that solvent thermal extraction process could dramatically remove the ash content and gradually enhance the caking performance and carbon content for low-rank coal. The ash content, carbon content, penetration distance, and caking index of modified coal were 0.86 wt%, 78.18 wt%, 35.48 mm, and 95%, respectively. Structural analysis results showed that the order degree and graphitization degree of BIOC-HPC coke were superior to those of coking coal coke, and the overall compactness of BIOC-HPC coke was improved. Compared with the coking coal coke, the gasification performance of coke could be improved by adding modified coal; the optimal addition ratio of the modified coal in coal blending for coking was between 10 wt% to 15 wt%. The gasification kinetic analysis indicated that the RPM model was the optimal model for simulating the gasification process of modified coal coke, and the activation energy was between 211.36 kJ/mol and 228.81 kJ/mol.