S.O.D.I.S.
S.O.D.I.S In Brief
Solar Water Disinfection (S.O.D.I.S.) is a simple, environmentally sustainable, low cost solution for drinking water treatment at house-hold level for people consuming microbiological contaminated raw water. S.O.D.I.S. uses solar energy to destroy pathogenic microorganisms causing water borne diseases and there with it improves the quality of drinking water.
Pathogenic Microorganisms are vulnerable to two affects of sunlight:
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radiation in the form of UV-A light with a wavelength between 320-400nm
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Heat (increased water temperature)
A synergy of these two effects occurs, as their combined effect is much greater than the sum of the single effects. This means that the mortality of the microorganisms in-creases when they are exposed to both temperature and UV-A light at the same time. S.O.D.I.S. is ideal to disinfect small quantities of water with low turbidity (Particulate matter that makes a cloudy or murky appearance). Contaminated water is filled into transparent plastic bottles and exposed to full sunlight for six hours. During this exposure to the sun the pathogens are destroyed. If cloudiness (turbidity) is greater than 50%, the water in the plastic bottles need to be exposed to full sunlight for 2 consecutive days in order for water to be safe for consumption. However, if the water temperatures exceed 50 degrees Celsius, one hour of exposure is sufficient to obtain safe drinking water. The efficiency of the treatment can be improves if the plastic bottles are exposed to sunlight from reflective surfaces (eg shiny aluminum sheeting or galvanized tin).
Courtesy of Preppers Are We
