The study aimed at the design, construction and performance evaluation of a model domestic wastewater treatment plant was carried out. The treatment unit was a Waste Stabilization Pond (WSP) comprised of one facultative pond, three maturation ponds, and a contact filtration unit, all in series. The effluent of the WSP, after filtration through clay media, had the BOD reduced to 15.4mg/l, from 356mg/L indicating a 95.67% removal level. A Faecal Coliform (FC) count of the influent sample gave 1x108 FC/100ml,. whereas the effluent gave 9 FC/100ml, which was 99.99% FC removal. It was concluded that the effluent from the WSP is therefore suitable for discharge to the environment. It also met the requirement of 25mg/L BOD standard of Federal Environmental Protection Agency (FEPA). A rice husk filter media was found to be non-promising earlier in the removal process. The treatment system can be recommended to private/public estates in order to have a more environmentally friendly discharge of domestic wastewater.
INTRODUCTION
As urban and industrial development increases, the quantity of waste generated also increases. These wastes pose a serious threat to public health when they are not readily disposed off. When these wastes are removed by water carriage system, they are termed wastewater. Wastewater is the used water or liquid waste of a community, which includes human and household waste together with street washings. Industrial waste and such ground and storm water may be mixed with it. The use of domestic wastewater for irrigation is advantageous for many reasons including water conservation, ease of disposal, nutrient utilization, and avoidance of surface water pollution. Nevertheless, it must be borne in mind that although the soil is an excellent adsorbent for most soluble pollutants, domestic wastewater must be treated before it can be used for crop irrigation to prevent the risk to both public and the environment.
This study aimed at designing and constructing a model waste stabilization pond and final contact filtration unit, for the treatment of influent domestic wastewater for environmentally friendlier discharge.