Municipal wastewater reclamation for non-potable reuse – environmental assessments based on pilot-plant studies and system modelling

Wastewater reclamation is an upcoming approach that will significantly affect wastewater treatment systems. Despite the fact that technology for treating wastewater to an effluent water quality that meets various quality standards for reuse is already available and applied, the reuse of water is not just a simple and straightforward road. Significant additional energy and civil infrastructure is required to treat the water to a standard that allows it to be safely reused. The total impact of treating and reusing water may be higher than the environmental benefits. Thus, it is crucial the life-cycle impacts from upstream and downstream processes of various reuse technologies, i.e. production of chemicals, energy use, eutrophication, sludge handling, etc. The present paper provides a comprehensive evaluation considering different reuse purposes, treatment technologies and plant size. The results of this study suggest that all these factors are highly significant for the environmental impact of wastewater treatment systems for non-potable applications.