Thermal-dissolution based carbon enrichment of biomass: Coking application of the Extract

• A novel pilot-scale biomass coking technology denoted as the TDCE is proposed • The pilot-scale TD Extract obviously improves coke quality and hot strength. • Biomasses are deeply aromatized during TD treatment, and becomes thermoplastic. • The thermoplastic Extract contributes to the formation of metaplast. The steel industry’s massive iron production in China necessitates urgent development of low-CO 2 -emission coking technologies. While carbon–neutral biomass represents a promising substitute for metallurgical coals, its detrimental impacts on coke quality raise significant concerns. This study experimentally validates a novel biomass-based metallurgical feedstock preparation method – Thermal-dissolution based carbon enrichment (TDCE) − through pilot-scale trials. By replacing 10–20% of caking/fat coal with biomass Extract, the coke strength after reaction of cokes increased from 41.72% to 44.80%, while the coke reactivity index decreased from 35.24% to 30.56%. These results confirm the technical viability and competitive advantages of biomass Extract over conventional bonded coals in terms of both cost-effectiveness and renewability. Mechanistic analysis reveals that the TDCE process induces deep aromatization and structural alignment in biomass, endowing the Extract with thermoplastic properties comparable to viscous components in bonded coals. This modified Extract significantly enhances metaplast formation during the plastic stage by extending the plastic temperature range. Moreover, the low ash content and renewability properties of Extract further contributes to the clean and low-CO 2 -emission preparation of metallurgical cokes. Therefore, this study provides a novel, green and effective biomass-based coking strategy with great potential for industrial application.