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Bid to commercialise arsenic removal system

The technology was initially developed by Professor Ashok Gadgil at Lawrence Berkeley National Laboratory.

In ECAR, electricity is used to continuously dissolve an iron electrode, forming a type of rust in the water. Arsenic in the water binds to the rust particles, which can then be removed. The rust particles are created electrochemically at the time of use, eliminating the need for a costly supply chain. Moreoever, electrochemical processes resulting from the use of electricity greatly improve the arsenic removal capacity (i.e. arsenic removed per unit iron input) relative to the common chemical methods of arsenic removal.

ECAR has many advantages over other low-cost arsenic removal methods such as chemical co-precipitation with ferric salts and filtration through activated alumina or granular iron-based adsorbent media, including a higher adsorption capacity due to the much larger surface area of newly precipitated nano-scale particles, no need to backwash media, (since media are removed by precipitation), low maintenance needs and a very low production of waste sludge.

ECAR operates at low voltages (< 3V in real groundwater with steel plates spaced 2 cm apart) and power can be supplied using grid, battery, or solar photovoltaic sources.