An international research group has reviewed the state of the art of life cycle assessment (LCA) in the context of wastewater treatment (WWT). They report that methodologies need to be updated to account for future challenges in the water treatment sector.
Life cycle assessment (LCA) is used to quantify the impacts associated with a product, service, or process from a cradle-to-grave perspective. LCA was first applied in the field of wastewater treatment (WWT) in the 1990s.
In the pursuit of more environmentally sustainable WWT, it is clear that LCA is a valuable tool to elucidate the broader environmental impacts of design and operation decisions. With growing interest from utilities, practitioners, and researchers in the use of LCA in WWT systems, it is important to review what has been achieved so far, and describe the challenges for the coming years.
This study by researchers in Spain, Australia, the US, and Denmark presents a comprehensive review of 45 papers dealing with life cycle assessment and wastewater treatment.
Analysis of the papers shows that within the constraints of the ISO standards, there is variability in the definition of the functional unit and the system boundaries, the selection of the impact assessment methodology, and the procedure followed for interpreting the results.
The need for stricter adherence to ISO methodological standards to ensure quality and transparency is made clear, and emerging challenges for LCA applications in WWT are discussed. These include a paradigm shift from pollutant removal to resource recovery, adapting LCA methodologies to new target compounds, developing regional factors, improving data quality, and reducing uncertainty.
