Snail Shell as a Biocoagulant Aid for the Precipitation of Colloidal Particles in Aqua Medium
1Adelagun, R.O.A, 2Oladoja N.A, 2Ololade I.A, 3Berezi E.P, 1Dina O.F, 2Bello H.A
1Chemistry Department, Wesley University of Science and Technology, Ondo
2Chemistry Department, Adekunle Ajasin University, Akungba Akoko, Ondo
3Chemistry Department, Bayelsa State College of Education, Brass Island, Bayelsa
Correspondence: jemiruth2009@yahoo.com Tel: 08065709024
Accepted on July 9, 2013
Abstract
Associated health and environmental problems with the use of conventional coagulants in water and wastewater treatment necessitated the need for alternative cost effective and environmentally acceptable coagulant. The ability of Snail Shell (SS) to act as a biocoagulant aid in the alum precipitation of colloidal particles in aqueous system was evaluated. Physico-chemical characterisation and mineralogical assemblage of the SS were evaluated. Synthetic turbid water of varying turbidities (50,100,300 NTU) was prepared by clay dispersion in deionised water. Both alum and SS were used separately to determine optimum dosages for the coagulation in different turbid wasters in a continuous variation in a jar test experiment. Effects of some process variables (coagulant / coagulant aid dosages and flocculation time) were also determined. The use of SS as a coagulant aid with alum precipitation showed that treated waters of lower residual turbidities were obtained from synthetic waters of high initial turbidities. Studies on the effects of flocculation time showed an optimum flocculation time of 30mins and redistribution/dispersion which was a normal phenomenon with the use of alum as coagulant did not occur when SS was used as a coagulant aid with alum.