UBC Theses and Dissertations
Plastic bags for water treatment : a new approach to solar disinfection of drinking water Pierik, Bradley
Waterborne disease is the cause of death for over 1.6 million people annually, and it is contracted primarily through inadequate access to safe drinking water, inadequate sanitation facilities, and inadequate hygiene practices. Solar disinfection (SODIS) is a low-cost water treatment technology that uses resources that are commonly available in much of the developing world, the most important being plastic beverage bottles. SODIS relies on solar ultraviolet radiation to kill germs in contaminated water contained in these plastic bottles, so that water can be rendered safe for consumption. However, in remote regions plastic bottles are often unavailable, or are prohibitively expensive. For this reason there exists a need for an alternative to plastic bottles for SODIS use in remote regions of the world. In this study, real and artificial sunlight exposures, standard microbiological enumeration methods, and tensile strength and optical transmittance measurement methods, were used to evaluate whether a plastic SODIS bag is a potential alternative to SODIS bottles. SODIS bags were found to yield as much as 74% higher treatment efficiencies than SODIS bottles, which may be because the bags were able to reach the elevated temperatures that are shown to cause accelerated treatment. The physical wear of hanging SODIS was approximately half the rate (47%) of SODIS bags’ wear and this suggests that hanging SODIS bags may have a longer useful life. A curve relating water depth and the efficiency of the water treatment process in SODIS bags under certain representative treatment conditions was generated and used to predict the optimal geometry of SODIS bags. Additionally, a new method was proposed for calculating the solar UV dose, which may be more appropriate than conventional methods. These findings suggest that SODIS bags may be an appropriate alternative to SODIS bottles. The findings further provide information to guide the design and implementation of SODIS bags.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International