Locally-affordable arsenic remediation for rural South Asia using electrocoagulation

Bangladesh and neighbouring areas face health threats from drinking arsenic-contaminated groundwater. The challenge is to develop arsenic remediation that is (1) affordable to most of the local population, (2) robust and easy to maintain long term, (3) technically effective for removing arsenic down to 10 ug/L in the presence of other competing ions in the water, and (4) does not require hazardous chemicals or produce excess levels of arsenic-laden waste. Electrochemical Arsenic Removal (ECAR) uses a small DC current and ordinary steel electrodes to produce iron rust in the arsenic-contaminated groundwater that binds arsenic and can be removed by filtration. We describe performance results using synthetic and real groundwater and describe the design of a 100L reactor. We demonstrate low production of waste sludge that is non-hazardous according to US EPA standards, and show preliminary results of successful sludge stabilization in concrete. Finally we estimate the operating costs.