APPLICATIONS OF TECHNOLOGY:
- Point-of-use remediation
- Small community drinking water systems
ADVANTAGES:
- Low initial cost
- Low operating cost
- Easily maintained and operated
- No corrosive or toxic chemicals needed for maintenance
- Highly effective
ABSTRACT:
Tens of millions of people worldwide must obtain drinking water from sources with high arsenic levels, which are associated with increased cancer and other health risks. Low-cost remediation systems frequently focus on point-of-use chemical adsorbents that are difficult to maintain, require a continuous supply chain, and are often abandoned by the user.
Electrochemical arsenic removal systems use a small amount of electricity and iron to continuously produce complexes of ferric hydroxide, a form of rust, and transform water-borne arsenic-III into arsenic-V, which quickly binds to the rust complex. The arsenic-laden rust can then be filtered or settled out to remove the arsenic from the water. Current systems based on natural rusting are limited, however, by the amount of rust produced. When too little rust is generated, arsenic passes through the device and renders it ineffective. These systems are also relatively ineffective at removing arsenic-III.
Berkeley Lab’s Ashok Gadgil has invented ECAR, an inexpensive, effective electrochemical arsenic removal system that accelerates the rate of rust production and effectively removes both arsenic-III and arsenic-V. The adsorbent is generated on site as needed to significantly reduce the need for a supply chain. The system was tested on ground water sources throughout Bangladesh and shown to achieve arsenic levels below the World Health Organization and EPA regulatory standard of 10 parts per billion (ppb).
The technology can be used in standing or flowing water sources, so it can be adapted for small community drinking water systems in addition to point-of-use applications. Innovative remediation steps in the Berkeley Lab invention yield an extremely low operating cost that opens the door for small community centers to recover their investment by selling clean water at an affordable price.
STATUS: Issued patents in Bangladesh (#1,005,081) and India (#300701). Available for licensing in Bangladesh and India only.
REFERENCE NUMBER: IB-2126