Thermodynamic and life cycle optimization of solar-coupled hydrogen production from discarded wood-based panels via supercritical water gasification

Discarded wood-based panels, containing a significant amount of amino resins, pose challenges for their conversion into clean energy using conventional treatment methods. A polygeneration system integrating supercritical water gasification was developed to process 10 t h−1 of discarded wood-based panels, enabling the co-production of clean hydrogen and power. A staged gasification configuration was first proposed to redistribute the highly localized heat demand of the endothermic gasification process, thereby alleviating material selection challenges in critical components. Based on thermodynamic sensitivity analysis of the autothermal system under various operating parameters, a solar-concentrating supplementary heating strategy was proposed, increasing hydrogen yield by 36.49% (from 759.55 to 1036.75 kg h−1) under typical operating conditions (620 °C, 50 wt%, and a ratio of 4.5). Energy and exergy analyses showed that the coupled system achieved higher performance, with energy efficiency increasing from 61.81% to 69.05% and exergy efficiency from 56.09% to 61.21%. Life cycle assessment revealed that the global warming potential of the coupled system during operation was higher than that of the original system due to increased CH4 emissions in the exhaust gas, which could be significantly reduced through further utilization. This study offers a theoretical basis to support the design optimization and industrial-scale deployment of solar-assisted supercritical water gasification polygeneration systems for biomass waste.