Advanced hydrogen production process design from cow manure supported by rural waste based on environmental and economic evaluation

Cow manure is generated in large quantities and offers a stable supply, making it a promising biomass resource. However, its high moisture content makes direct gasification challenging, and it is therefore commonly treated through incineration, landfilling, or composting, all of which can cause severe air and soil pollution. To address these issues, this study designed and evaluated a gasification process that produces hydrogen without a separate drying step by blending cow manure with rice straw. The results showed that the blended gasification process achieved optimal hydrogen production and a favorable H₂/CO ratio at 700 °C and a steam-to-fuel ratio of 0.4, while additional tail-gas recycling further increased hydrogen output. Life-cycle assessment revealed that blended gasification reduced global warming potential by nearly half compared with conventional pathways, and techno-economic analysis indicated a 24% reduction in hydrogen production cost. At an industry-scale capacity of 1000 t/d, the hydrogen production cost was estimated at 2.75 USD/kg, which is lower than the target cost of 4 USD/kg. Overall, the findings demonstrate that directly gasifying high-moisture cow manure by blending it with dried agricultural residues offers a practical treatment pathway and represents a promising approach for decentralized, low-carbon hydrogen production in rural regions.