Disinfection of water containing Escherichia coli by use of a compound parabolic concentrator: effect of global solar radiation and reactor surface treatment

Abstract

Effects of photocatalytic and solar disinfection on Escherichia coli K12 (TISTR 780) are examined. Experiments were conducted with titanium dioxide (TiO2) as catalyst, coated on plates by thermal spraying, with global solar illumination. Inactivation of E. coli as a function of time was conducted to find the rate of inactivation of the bacteria. The results revealed that the solar disinfection in the absence of the catalyst plates did not significantly affect the rate of inactivation of the bacteria when increasing the reactor surface area of solar illumination. Black reactor surfaces were slightly more affected when increasing the area of the reactor surface. However, the catalyst reactor surface had the greatest effect on inactivation of the bacteria when the reactor surface area was increased. Water temperature less than 45 °C did not affect the decrease in the rate of inactivation of the bacteria for either solar or photocatalytic disinfection.