Assessment of the interchangeability of coal-biomass syngas with natural gas for atmospheric burners and high-pressure combustion applications

Syngas from biomass-coal co-gasification represents a viable energy vector to incorporate alternative energy sources into electricity production and industrial heating. Although the low energy content of syngas hinders its use, syngas-natural gas blends could overcome this challenge. This study assesses syngas-natural gas inter-changeability in atmospheric burners via the combustion potential and the corrected Wobbe index according to Delbourg's approach. Likewise, this research evaluates methane number as an interchangeability indicator for high-pressure combustion. The syngas originated from a Top-Lit UpDraft gasifier, using coal-biomass blends of 0-100, 25-75, and 45-55 wt %, with air as the gasifying agent. The syngas featured a Lower Heating Value ranging from 3.0 to 3.8 MJ Nm-3. Results based on Delbourg's approach indicated that syngas-natural gas blends of up to 15 vol % syngas could operate in atmospheric natural gas burners without modifications. Furthermore, the methane number for syngas-natural gas blends of 15 vol % syngas was 5.8% higher than that of natural gas. The results show slight variations in flue gas composition, adiabatic flame temperature, and laminar flame ve-locity between natural gas and syngas-natural gas blends. The study showcases the potential of using syngas-natural gas blends in thermal applications and identifies key areas for further research.