Pilot study of a horizontal roughing filtration system treating greywater generated from a peri-urban community in Durban, South Africa

There is a growing pressure on the available freshwater resources in South Africa and many other countries around the world. This has led to a large scale of interest in the application of water reclamation and reuse of wastewater as alternative water supply sources. This is becoming critical to sustain development and economic growth in the southern Africa region. This study investigated the performance of a horizontal roughing filtration system treating greywater generated from a peri-urban settlement in Durban, South Africa. The horizontal roughing filtration system consists of three compartments containing different sizes of gravels that serve as the filter media. The horizontal roughing filter was operated at a filtration rate of 0.3 m/hr for 90 days. The results indicated that at this low filtration rate, effective reduction in turbidity, conductivity, chemical oxygen demand and total solids can be achieved. Overall average removal efficiencies of 90% turbidity, 70% chemical oxygen demand, 86% conductivity, and 84% total solids were obtained for the entire duration of operation of the horizontal roughing filtration system. Thus, it was concluded that the horizontal roughing filtration system is suitable for the treatment of greywater for non-potable reuse applications although further investigation needs to be conducted for the microbial removal during the treatment.