Life cycle assessment review of struvite precipitation in wastewater treatment

Life cycle assessment (LCA) has been widely used to assess the environmental impacts of wastewater treatment, and has started to be applied to wastewater nutrient recovery technologies such as struvite precipitation. A small number of studies have been conducted thus far, and this review surveys several of those studies assessing the current state of knowledge with regards to the environmental impacts of struvite recovery in wastewater treatment. The focus is on analyzing trends, good practice, and identifying areas of discrepancy or concern by evaluating aspects of each of the four LCA steps as defined by the International Organization for Standardization (ISO): the definition of a goal and scope, inventory analysis, impact assessment, and interpretation of result. Evaluation of the studies considered here highlights the need for further LCA research of struvite recovery systems focusing on full scale operations outside of Europe. Additionally, there is a need for increased transparency and consistency in the boundaries of considered systems; specifically in quantifying an equivalent amount of fertilizer that is offset by struvite and with the infrastructure included and its lifespan.