Development of a solar water disinfection treatment system for sustainable water use in developing countries

Direct dependence on surface water poses a threat to human health when consumed without treatment. While solar water disinfection treatment systems (SODIS) help improve the quality of surface water for rural households, SODIS approaches, implementation, and adoption have some limitations. Consequently, this study developed a hybrid water disinfection treatment system at the laboratory scale, integrating novel Advanced Oxidation Processes (AOP). Additionally, surface water quality, the challenges, and enablers of effective implementation of SODIS in rural Ghana were assessed. Two hybrid disinfection systems in continuous flow with reactor volumes of 300 ml each were operated. The disinfection of Staphylococcus aureus in the hybrid disinfection system achieved a 99.60% reduction at 360 min, while complete disinfection (100%) was achieved with photocatalyst integration without regrowth after post-treatment storage for 24 hr. A proportionate 96.24% disinfection rate was achieved for Salmonella senftenberg within 360 min in the hybrid disinfection system while 100% disinfection was achieved with the integration of a photocatalyst. Similarly, no regrowth of Salmonella senftenberg was observed after 24 hr post-treatment storage. The disinfection of Bacillus subtilis was optimized from 95.46% in the hybrid treatment system to 99.99% in the hybrid system with photocatalyst within 360 min. Furthermore, a disinfection proportion of 99.97% was achieved in the hybrid system at 360 min, while 100% disinfection was achieved with the hybrid disinfection system at 300 min for Escherichia coli with the integration of photocatalyst. No Escherichia coli re-growth was observed after a 24 hr post treatment storage. The water quality index generated based on the surface water quality assessment showed that all surface water sources are polluted largely due to total and faecal coliforms. The results proved that SODIS can serve as a suitable water treatment approach for adoption in the Sawla-Tuna-Kalba (STK) District. Out of 1155 respondents, 97% of the respondents are willing to accept and adopt a SODIS. Based on the findings, the enablers of effective SODIS implementation were willingness to pay for SODIS, household and community participation, and willingness to use water from SODIS. The identified barriers to the implementation of SODIS were environmental, technological, political and legal, and economic barriers. Compositional and contextual factors such as age, marital status, education, religion, and geographical location significantly mediate and attenuate households’ willingness to accept and adopt SODIS in the STK District of Ghana.