In Bujumbura, Burundi, new water works with slow sand filtration treatment went into operation in May 1987. Within a short time filter running time dropped to an unacceptable 8 days.
|Difficulties in the operation of new slow sand filters in Africa
|Year of Publication
|16 p.: fig., tab.
|Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ)
|burundi bujumbura, calcium carbonate, chemical precipitation, hydraulics, m, ph, slow sand filtration
In Bujumbura, Burundi, new water works with slow sand filtration treatment went into operation in May 1987. Within a short time filter running time dropped to an unacceptable 8 days. The reason is that there are unusual characteristics in the raw water which is taken from Lake Tanganyika. A high pH-value of 9.0 is responsible for the precipitation of calcium carbonate substances in the filter. The sand surface is heavily encrusted and costly efforts are necessary to remove the encrusted material. Neutralisation of the raw water is economically not feasible. A higher filtration velocity is recommended to reduce the formation of deposits in the filter. Algae growth is not a serious problem and should not be controlled.