| Arsenic Method OK for Bangladesh |
| Following a two-year test of its
low-cost, small-scale arsenic removal method, Stevens Institute of
Technology has agreed to make the process available to treat contaminated
well water in Bangladesh. Created in 1999 by engineers at Stevens' Center for Environmental Engineering, the simple system requires no electricity, costs only a few dollars a year per family, and effectively reduces arsenic in well water to acceptable levels for human consumption (at or below World Health Organization standards). To produce clean drinking water with Stevens' technology, a family collects well water in a bucket and adds a packet containing coagulant chemicals to the water. After mixing, the water is transferred to another bucket containing a sand-based filter material. The water that comes out of that bucket's bottom spout is safe for drinking. "No electricity is required, and for most people, learning the process will be quite easy," says George Korfiatis, director of the Center for Environmental Engineering. Tests conducted in Bangladesh have demonstrated that Stevens' filtration can effectively remove arsenic in well water. Preliminary tests revealed arsenic concentrations between 280 and 587 micrograms per liter (mg/L) in five wells in Kishoreganj and Munshiganj districts. When the water was treated with two chemical tablets per bucket of water, followed by filtration through the family-size filter, arsenic concentration was reduced to less than 23 mg/L. Cost for the chemicals is less than $2 per family for a year's supply. Initial water flow rates were about 1.5 L per minute. When 200 L were filtered, the flow rate decreased to about 0.5 L per minute. Arsenic concentration in the filtered water decreased when more water was filtered. The sand media requires washing every one to two weeks to remove fine solid particles. Less than two buckets of well water are necessary. After a few minutes of washing, the sand may be reused for filtration. The wash water is poured into a container for collection of solids. Residuals left in the bottom of the container can be safely recycled in construction projects by mixing them with concrete or asphalt. The success of the Bangladeshi pilot projects has led to a collaborative agreement with Earth Identity Project, a nongovernmental organization in Bangladesh. Stevens and Earth Identity Project have agreed jointly to develop a technology center that will deploy Stevens Technology for Arsenic Remediation (STAR) in Bangladesh. The STAR Technology Center will be responsible for all aspects of technology development and field deployment of the Stevens technology, including manufacturing, distribution and installation of STAR systems, treatment chemicals, monitoring, analysis, research, education, and training. Contact: George Korfiatis, Stevens Institute of Technology's
Center for Environmental Engineering, James C. Nicoll Laboratory,
Hoboken, NJ 07030; Tel: 201/216-5348,
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