Transition to circular economy in the water sector: the case study of Corleone, Italy

The urgent need to address environmental challenges such as increasing sewage sludge production and greenhouse gas emissions in wastewater management has spurred a global transition toward a circular economy approach. This chapter delves into the Corleone (Italy) wastewater treatment plant (WWTP) case study, focusing on the critical role of plant configuration and optimization in mitigating sewage sludge production and reducing the carbon footprint. By implementing innovative techniques like the oxic settling anaerobic (OSA) process, Corleone WWTP exemplifies tangible reductions in sewage sludge production and carbon footprint, aligning with circular economy objectives and European Commission recommendations. Additionally, advancements in phosphate removal highlight improved nutrient recovery capabilities under the OSA process. Further, water reuse was established by an ultrafiltration membrane system placed after the secondary treatments. Achieving optimal wastewater treatment processes requires careful consideration of trade-offs between effluent quality, energy consumption, and carbon footprint. Through dynamic simulations and scenario analyses using novel modeling approaches, this chapter sheds light on the complexities involved, underscoring the necessity for technological innovation and integrated decision-making in wastewater management.