Potable water treatment for some asbestiform minerals: optimization and turbidity data

A study has been undertaken to optimize conventional alum coagulation treatment of water for asbestos fibre removal. The results indicate that both the alum and polyelectrolyte concentrations significantly effect the quality of the treated water. Optimum results were obtained with alum concentrations of 30–50 ppm and polyelectrolyte concentrations of 0.3–0.6 ppm. Rapid coagulation/direct filtration has been evaluated and the results found to be comparable to conventional treatment employing flocculation and sedimentation. A survey of turbidities and fibre concentrations for several municipal water supplies indicate that no systematic relationship exists between these two parameters.