This review aims to discern a treatment for grey water by
examining grey water characteristics, reuse standards,
technology performance and costs. The review reveals that the
systems for treating grey water, whatever its quality, should
consist of processes that are able to trap pollutants with a
small particle size and convert organic matter to mineralized
compounds. For efficient, simple and affordable treatment of
grey water with safe effluent reuse, a combined anaerobic-
aerobic process is recommended, with disinfection being an
optional step. The removal and subsequent conversion of
suspended and colloidal particles in the anaerobic process need
further improvement. Furthermore, the reuse standards should be
revised and classified considering the reuse options and
requirements.