ABSTRACT
High salinity and arsenic (As) concentrations in groundwater are prevalent problems in the tidal delta plains of South and Southeast Asia. Pilot trials for As removal and groundwater desalination were carried out in a private home in Tra Vinh in the Mekong Delta, Vietnam. Desalination was conducted by capacitive deionisation (CDI), a rather new technology showing lower specific energy consumption compared to other desalination technologies. In order to treat anoxic groundwater with As(III), which is usually associated with high Fe, a pre-oxidation step and removal of Fe(oxy)hydroxide is mandatory to avoid clogging of the CDI unit. This was conducted by use of subsurface As removal having the advantage of being a zero waste process. The process was operated by use of photovoltaics (PV) and a small wind turbine.
