Year: 2025
Type: article
Abstract: Due to the sludge treatment processes such as anaerobic digestion processes release substantial amounts of biogenic CO2, Wastewater treatment plants (WWTPs) represent significant carbon emission sources consequently. On the one hand, existing carbon capture technologies generally lack effective integrated, on the other hand, due to the green tides cause severe damage on ecological, their biomass remains an underutilized potential carbon sink resource yet. Thereby, this review trying to coupling supercritical water gasification (SCWG), organic rankine cycle (ORC), and Ulva biochar sequestration into a synergistic technological framework. SCWG technology which is at above 374C and the pressure at 22Mpa situation to directly processes wet sludge, and produce hydrogen and liquid co2, the whole processes can save high energy consumption drying step. In order to achieving system self-sufficiency, through the ORC recover waste heat 30% of input energy which is generated by exothermic reaction to driving carbon capture units. Then use containerized systems transport the captured liquid co2 to Ulva farms, in order to promoting algal photosynthesis, use micro-bubble aeration enhances dissolution. The obtained Ulva undergoes pyrosis to form high stability biochar, the whole operation completing a carbon closed loop. Comparing conventional methods this comprehensive methods can reduces greenhouse gas emissions by 3.88.2 kg CO/kg dry sludge, coordinate policy mechanisms such as carbon tax and subsidies can improve economic feasibility. This review indicates to promoting industries significance reduce emissions thereby promoting the process of carbon neutrality there is a feasible approach which through elimination of sludge drying, achievement of energy self-sufficiency, and establishment of a carbon closed-loop.
Authors: Qixuan Feng, Yihong Wang
Institutions: Oklahoma State University, University of Nottingham
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4413183264