Supercritical water gasification (SCWG) technology has attracted significant attention due to its advantages in efficiently treating high-moisture materials and producing hydrogen-rich gas, offering an attractive option for sewage sludge (SS) treatment. This study develops an efficient hydrogen production system that integrates SCWG, Organic Rankine Cycle (ORC), and carbon capture and storage (CCS) technologies. A comprehensive life cycle techno-environmental-economic assessment of SS to hydrogen (SStH) process with SCWG technology is conducted. The results indicate that gasification temperature and moisture content are the primary factors affecting H2 yield and system efficiency, while gasification pressure has a minor impact. The system demonstrates favorable exergy efficiency (30.93 %) and a certain advantage in overall environmental impact (66.99 mPE). Electricity and natural gas particularly contributed to the environmental impact indicators. Reducing energy consumption or seeking alternative low-emission renewable energy sources will further reduce its environmental impact. The economic feasibility of SStH is sensitive to energy prices, with the cost of natural gas and the selling price of H2 being critical factors. Strategies such as reducing reliance on natural gas, increasing hydrogen sales prices, and leveraging carbon tax credits and sludge subsidies are vital for enhancing the economic viability of SStH with SCWG technology. Renewable energy utilization and co-gasification are expected to further reduce the operating costs of SCWG.

中文翻译：

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从污水污泥到氢气：超临界水气化、有机朗肯循环和碳捕获与封存联合系统的生命周期技术-环境-经济评估


超临界水气化 （SCWG） 技术因其在有效处理高水分材料和产生富氢气体方面的优势而备受关注，为污水污泥 （SS） 处理提供了极具吸引力的选择。本研究开发了一种高效的制氢系统，该系统集成了 SCWG、有机朗肯循环 （ORC） 和碳捕获与封存 （CCS） 技术。使用 SCWG 技术对 SS 制氢 （SStH） 过程进行了全面的生命周期技术-环境-经济评估。结果表明，气化温度和水分含量是影响 H2 产率和系统效率的主要因素，而气化压力的影响较小。该系统具有良好的用能效率 （30.93%） 和在整体环境影响 （66.99 mPE） 方面具有一定的优势。电力和天然气对环境影响指标的贡献尤其大。减少能源消耗或寻求替代的低排放可再生能源将进一步减少其对环境的影响。SStH 的经济可行性对能源价格很敏感，天然气的成本和 H2 的销售价格是关键因素。减少对天然气的依赖、提高氢气销售价格以及利用碳税抵免和污泥补贴等策略对于使用 SCWG 技术提高 SStH 的经济可行性至关重要。可再生能源利用和共气化有望进一步降低 SCWG 的运营成本。