COMPACT CONSTRUCTED WETLAND FOR SHOWER GREY WATER TREATMENT FOR REUSE IN WATER CLOSETS

Abstract

Constructed wetland systems have stood out for their efficiency for the treatment of wastewater. However, they usually have large dimensions, which can make it unfeasible in urban areas. The objective of this work is to evaluate if a compact constructed wetland system can treat the grey water from the shower, in order to reuse the treated water in sanitary toilets. For this purpose, a field system with easily available materials was built, and samples of grey water and treated effluent were evaluated. The system could remove organic matter (removal of BOD and COD equal to 89% and 84%, respectively), color (96% removal) and turbidity (70% removal). Thermotolerant coliforms were not detected in the majority of the samples. With the exception of turbidity (70% removal) and solids (67% removal), the other results are according to the limits of the quality parameters of the reference documents. It is important to consider an initial period until stabilization is reached and maintains constant and a greater organic matter removal. This also happens after system maintenance, when usually a superficial layer of sand is removed. This maintenance was necessary after 16 weeks of operation; thus, it is important that users are aware of this task when choosing this system.