Purifying polluted water through hemodialysis filters for poor villages without electricity: The Easy Water for Everyone approach and experience

Abstract

Given the need for treating polluted drinking water, our NGO Easy Water for Everyone has produced pure water in remote villages without power and achieved health benefits. With the goal of reaching more needy populations we report our experience and successful implementation in Ghana. In 20 villages polluted water is pumped every few days to an elevated water tank connected to a filtration device leading to a faucet. Repurposed hemodialyzers with polysulfone membranes, having a filter pore size of 0.003 micrometres, prevent passage of pathogens. Gravity from a 3 m height pushes water through the membrane whenever the faucet is open. Backflushing of the hemodialyzer membrane three times daily removes built-up organic material and maintains flow rates of 250 L/hour for at least two years. Filtered water has been culture-negative. Management of problems and optimization are reported. The five-year cost per village of <1,500 population averaged <2 US$ per day.