Comparative evaluation of two novel disinfection methods for small-community water treatment in developing countries

Two novel disinfection methods, the Moggod (mixed oxidant gases generated on demand) and an iodinated resin cartridge were assessed in terms of their operational performance, reliability and chemical and power consumption in comparison with a conventional hypochlorite doser. A pilot-plant water treatment system was designed to correspond to a small community of 500 people with a demand of 50 litres per person per day. The Moggod, a commercially available electrolytic cell, was found to be easy to maintain and operate, consuming only sodium chloride, water and power. It reliably gave a residual level of chlorine in the treated water and 100% kill of E. coli bacteria throughout the 15 week study. It was expected, however, that the use of low-quality salt would lead to blockage of the Moggod-cell membrane. The iodinated resin cartridge was not succesful as a disinfection method as the resin lost its available iodine very rapidly and bacterial breakthrough occurred. Iodinated charcoals, which could be locally produced in developing countries, were thought to offer more hope of success.