Potable Water Treatment using Synthetic Polyelectrolytes with Magnetite Particles

The potential usefulness of cationic polyelectrolytes in treating river water used for drinking purposes was investigated with particular focus on the removal of turbidity. A series of experiments were carried out using four commercial polyelectrolytes such as Magnafloc, Richfloc, 950C and 950 Cap. The efficacy of the process was first examined with demineralised water of known artificially produced turbidity. The optimum pH, concentration of reagents in clarification and the conditions affecting the interaction between the reagents and the turbid particles in water were investigated. Rapid coagulation removing some heavy metal ions and colour, was obtained by the use of fine magnetite particles as carriers. The reagent 950C was found to be superior compared to other reagents. It was possible to reduce the turbidity of the river water from 236 NTU to 3.6 at 5.0 mg/L of reagent concentration in conjunction with Al₂(SO₄)₃ and magnetite particles in a period of five minutes.