Inactivation of E. coli Present in Lake Water Using UV Reactor

Microbial contaminated water is the main cause for many water-borne diseases in developing countries. To make contaminated water microbial safe for drinking, disinfection is needed. Hence, this research work was carried out to disinfect lake water containing E. coli by using UV light. Four experimental setups were designed, i.e., UV reactor. Initially, the uncovered UV reactor (pair of 6 W UV light) was fabricated to disinfect the lake water for inactivation of E. coli, Later on, the UV reactors were modified three times by reflective mirrors (Modified 1), increased length and decreasing height and increased UV intensity (Modified 3). All experimentation were carried out at varying contact time, viz. 1:30 min, 2:30 min and 3:15 min. Raw lake water was characterized for and physicochemical and bacteriological parameters, viz. turbidity (1–6 NTU), temperature (23.9–25.4 °C), pH (6–8.5) and E. coli. Average E. coli in raw lake water was found to be 2400 MPN/100 ml, which exceeds the permissible limit as per IS:10500, (2012), Results of the investigation indicated that increased UV intensity (Modified 3) showed 99.99% inactivation, i.e., 3-log reduction.