Hydrogen-rich syngas derived from smouldering biomass and hydrocarbon wastes

Smouldering has recently been developed as a cost effective and energy efficient technology for challenging wastes. These systems are often used to eliminate environmental liabilities, and only minimal work has explored their use for generating useful by-products. This study addressed this research gap and demonstrated that applied smouldering systems can be tuned to favour hydrogen production. Calcium oxide and steam were added to the smouldering system, which completely treated woody biomass and coal tar, while producing hydrogen. The maximum hydrogen concentration achieved in the smouldering system was 33.7%, resulting in a net energy positive syngas. Results suggest that both heterogenous gasification and the water gas shift were key mechanisms behind hydrogen formation. These results indicate that smouldering systems can be used as a new method to sustainably produce hydrogen-rich syngas from challenging wastes.