Re-Design of El Haj Yousif sewage treatment plant

In the Recent years Sudan has experienced a very big industrial development, but this has not been accompanied with interest to avoid environmental problems due to the insufficient expansion & development in sewer system. Sewerage systems are only present in the capital city where there are only two operating wastewater treatment plants at El Haj Yousif and Soba . In Khartoum North Industrial Area which accommodates simple and light industries like foods, soap, and textiles, which produce a few waste, the quality and quantities of industrial waste have changed over the years resulting in treatment and mechanical problems that effected El Haj Yousif treatment plant badly, and its efficiency decreased since 1975 till it stopped totally in 1998. The Aim of this Research is to put El Haj Yousif treatment plant into work. In order to achieve this objective the following has been assumed: o The connection of domestic waste water of Khartoum North Residential area to dilute the industrial waste and improve its sewage nature because it contains the microorganism and organic matters needed for biodegradation of the waste. o Evaluation of the quantities and quality of mixed waste water (domestic and industrial) to determine the basis for design. o Rehabilitation of the preliminary facilities (Screens & grid chamber) and Re-design of primary clarifiers and Design of aeration tank instead of stabilization ponds. o Design secondary clarifier tanks for settling of activated sludge & recycling part of it to the aeration tank and waste the remaining to digestion. o Using of effluent water as irrigation water for the cultivated area in Koko scheme after mixing with the irrigation water in Koko canal