Abstract

The main objective of this work was to evaluate the suitability and efficiency of a natural coagulant from Moringa oleifera seeds in treating high turbidity water in the processes of slow direct filtration and sedimentation. In developing countries such as Brazil, the technologies for water treatment shall enable people living in potable-water deficient regions to purify water in easy and self-sustainable ways and at a low cost as well. Within this proposition, a potential use of M. oleifera has been suggested in several previous studies. In this work, a flocculation device made of pet bottles plus three filters consisting of pet bottles and non-woven synthetic fabric was used in the water treatment by slow direct filtration. The water output to the filters was of approximately 4 m³m-² per day. The water treatment by sedimentation comprised a flocculation unit made of pet bottles and a sedimentation tank. Synthetic bentonite-water was used as the untreated water, which was chosen due to its proper qualitative characteristics for the experiments. The data demonstrated that the M. oleifera coagulant was efficient in the treatment of water with high turbidity (50 to 100 NTU) in the tested systems of slow filtration through synthetic non-woven fabric and of sedimentation.

Key words: Moringa oleifera, slow filtration, sedimentation, purification of water.