Accelerating the solar disinfection process of water using modified compound parabolic concentrators (CPC s ) mirror.

Solar disinfection can significantly improve the microbiological quality of drinking water. Water samples of 0, 50, and 100 nephelometric turbidity units spiked with fecal coliforms (107 CFU/mL) were exposed to natural sunshine in 1 L quartz glass tubes fitted with three different design compound parabolic concentrators (CPC1), CPC2, and CPC3, with concentration factor of the solar radiation of 1. On clear days, the complete inactivation times (more than 7-log unit reduction in bacterial population) in the systems with CPC1, CPC2, and CPC3were 90, 20, and 15 min, respectively. The maximum obtained temperatures in the water samples were 57.9°C for CPC1, 77.7°C for CPC2, and 80°C for CPC3. The use of CPC2–3significantly improved the efficiency of the old CPCStechnique, since these systems shortened the exposure times to solar radiation and also minimized the negative effects of turbidity and also regrowth was zero in the disinfected samples. Overall, this technology has been proved to be a good method enhancement to inactivate micro-organisms under real conditions and represents a good alternative technique to drinking water treatment in developing countries. [ABSTRACT FROM PUBLISHER]