Research
| Title： | Sustainability of emerging sludge resource recovery scenarios: Process modeling and life cycle assessment |
|---|---|
| First author： | Zhou, Hao; Wang, Zhiyue; Liu, Binbin; He, Hang; Peng, Sainan; Zhang, Yu; Li, Lanfeng; Ai, Jing; Yu, Junxia; Zhang, Weijun |
| Journal： | RESOURCES CONSERVATION AND RECYCLING |
| Years： | 2025 |
| DOI： | 10.1016/j.resconrec.2025.108165 |
| Abstract： | A novel sewage sludge management approach seeks to replace conventional anaerobic digestion (AD) and combined heat and power generation with high-value organic chemical recovery processes, aiming to promote a more efficient circular economy. However, determining the most sustainable recovery form and pathway for sludge-based products requires quantitative analysis. This study modeled scenarios for producing volatile fatty acids (VFAs), polyhydroxyalkanoates (PHAs), and proteins from sludge, clarified their substance flows, and evaluated their sustainability using life cycle assessment. Results indicated that the sludge-to-VFAs process is more sustainable than conventional AD, PHAs production, and protein extraction. Based on dynamic simulations, transforming conventional AD in wastewater treatment plants to the sludge-to-VFAs process could reduce its environmental burden and actual operational costs by approximately 13 % and 17 %, respectively. Overall, from a life cycle perspective, prioritizing utilization efficiency is crucial, as high-value sludge-based products often obtained at the expense of additional chemicals and energy consumption. |
