Environmental Sustainability Assessment of Wastewater Treatment Methods: An LCA Approach

Sustainability holds profound implications for the field of engineering, particularly in the design and operation of wastewater treatment plants. The life cycle assessment (LCA) approach is suited for evaluating the sustainability of a wastewater treatment plant design. The current study compared several wastewater treatment systems using an LCA methodology. The assessment focuses on two WWT methods: moving bed biofilm reactor (MBBR) and sequential batch reactor (SBR), which was compared with the conventional activated sludge process (ASP). Environmental impacts were analyzed using the CML-IA baseline impact assessment method and SimaPro software using the Ecoinvent database. The analysis shows that the MBBR has the highest environmental impacts compared to SBR and ASP. Electricity consumption emerged as the primary driver of these environmental impacts. The global warming potential for MBBR is recorded at 1.82 kg CO2 equivalent, marking the highest among the considered treatment methods. In cases where the ASP method might be impractical, the SBR method presents itself as a more sustainable alternative, boasting lower scores across all critical effect areas considered. This study not only sheds light on the environmental hotspots within the WWT process but also aids in assessing potential environmental effects associated with WWTPs. Furthermore, it is important to note that an uncertainty analysis was conducted in this study, enhancing the robustness and reliability of the findings.