Abstract: To improve the resource utilization efficiency of combustible solid waste and explore efficient low-carbon production paths for hydrogen energy, an integrated energy-exergy-environment (3E) assessment model was constructed for a commercial combustible waste gasification poly-generation (CWGP) system to evaluate its technical performance and environmental impacts. Through sensitivity analysis, the global optimal operating parameters were determined as follows: a gasification temperature of 950 ℃, a steam-to-waste ratio of 0.5, and an equivalence ratio of 0.30. Under these conditions, the total yield of CO and H2 was 488.7 kmol/h, and the total thermal efficiency of the system reached 64.13%. The overall exergy efficiency was 58.69%, with the gasification reaction unit (GSF) being the largest source of exergy destruction (56.09%) due to the strong irreversibility of high-temperature chemical reactions. Life cycle assessment (LCA) results showed that treating 1 ton of solid waste yielded 89.7 kg of hydrogen with a carbon capture rate as high as 91.1%, and a total life cycle global warming (GW) potential of 413.14 kg. Normalization analysis further identified ecotoxicity as the primary environmental load of the system, stemming from the external electricity consumption of 205.1 kWh/t, which contributed to the majority of environmental indicators besides GW. In conclusion, enhancing process thermal efficiency to reduce auxiliary power consumption and introducing renewable energy supply are the core paths for synergistically reducing the carbon footprint and environmental toxicity of the poly-generation system, thereby achieving a green transition of the process.

Key words: commercial combustible waste, poly-generation system, hydrogen production, process optimization, life cycle assessment