Evaluation Of The Efficiency And Benefits Of A Pilot Scaled Decentralized Faecal Sludge Treatment System In Kampala

Abstract

Many peri-urban cities of Sub-Saharan Africa are overwhelmed with overloading the existing centralised wastewater treatment plants and high capital costs of operations and maintenance. In this work, a pilot decentralized faecal sludge treatment system (DEFASTS) was constructed in Kampala for assessing the performance and potential benefits of the treatment system. It consisted of a sedimentation tank, 2 m3, where liquid overflowed sequentially through anaerobic baffled reactor and anaerobic filter. Effluent was polished by a Cyperus papyrus planted gravel filter. The system was loaded daily with 0.5m3/day of mixed raw faecal sludge from both septic tanks and pit latrines operated with a total retention time of 12.52 days. Monitored parameters were; Chemical Oxygen Demand, five-day Biochemical Oxygen Demand total suspended solids pH, temperature, total phosphorus, total nitrogen faecal coliforms total volatile solids and ash content. Results obtained were 95.7±24 %, 96.4±1.9%, 96.8±1.8%, 78.4± 24.2%, 76.6±29.8% and 99 ±1.6% respectively.