STUDIES ON 'ALUMINIUM CHLORIDE AS SEWAGE COAGULANT

Abstract

The direct physico.chenicai treatnent of the Municipal sewage without any biological treatment has been in vogue since 1970. The treatment has been found to be fairly successful !.'with different coagulants, such as Alum, FeC13 and hydrated lime etc. in terms of TOO, BCD, COD and S.S. removal. in the present study Aluminium Chloride was used as sewage coagulant and was found to be a fairly good coagulant for the Municipal sewage physice-chemical treatment The COD removal was fairly high (around 90 ./. ) and also S.S. were removed upto a great extent (around 80 1.). The performance of Aluminium Chloride in removal of COD from the Municipal sewage is much better as compared to the traditional Alum. The Aluminium Chlou. ride was used lesser in quantity as compared to Alum for the COD removal but for the S.S. removal (with S.S.greater than) malitre) the quantity of Aluminium Chloride used was more as compared to Alum. So Aluminium Chloride which has been found to be equivalent to Alum in Turbidity removal from water is also fairly successful in the direct physico-chemical treatment of Municipal Sewage.