WRRCTMR No.54 Bromine Chloride: An Alternative Disinfectant to Chlorine

Abstract

Bromine chloride (BrCl) was evaluated as an alternative to chlorine as a disinfectant of water and waste water by comparing the efficiency of these two chemicals to inactivate type 1 poliovirus seeded in various aqueous solutions. In a nitrogen-free buffer at pH 6.0, the minimum concentration of BrCl required to effectively inactivate poliovirus (4-log reduction after 15 min at 25°C) was 0.15 mg/l, whereas 0.3 mg/l of chlorine was required to accomplish the same effect. The virus inactivating efficiency of BrCl was not interfered within the range of pH 6 to 1O. Furthermore, the addition of various concentrations of glycine and NH4Cl to the nitrogen-free buffer solutions more effectively interfered with the virus inactivating properties of chlorine than BrCl. To simulate waste water disinfection, 1 to 5 mg/l of BrCl and chlorine were added to activated sludge treated sewage effluent seeded with poliovirus, mixed well, and titered after 15 min at 25°C. The results show that the inactivating effects of 1, 2, and 3 mg/l dose of both chlorine and BrCl were equivalent and inefficient. However, at a dose of 5 mg/l, BrCl inactivated 5 logs of virus, whereas chlorine inactivated only 2 logs of virus. These results indicate that BrCl should be seriously considered as a potential alternative to chlorine as a disinfectant.