EFFECT OF CARBON DIOXIDE INJECTION ON SECONDARY EFFLUENT CHLORINATION

Abstract

Effects of carbon dioxide injection before the chlorination on inactivation efficiencies of E. coli B, S. faecalis and coliphages in the secondary effluent were investigated.
The carbon dioxide injection into the secondary effluent could decrease the pH value of the secondary effluent from 6.1 to 4.8.
The carbon dioxide injection brought about more effective inactivation for E. coli B when the chlorine doses were 1.5mgCl/l and 3.7mgCl/l, respectively.
However, the carbon dioxide injection before the chlorination did not make better efficiency for the inactivation of S. faecalis.
The coliphages were also inactivated more effectively by the carbon dioxide injection before the chlorination when the chlorine doses were 5.0mgCl/l and 12.0mgCl/l, respectively.