Long-term and robust treatment system for treating reduced groundwater containing iron and arsenic by adding atmospheric oxygen: The easy-to-use FERMANOX® UEE/SAR removes arsenic from groundwater without generating toxic waste or waste products.
The FERMANOX® UEE/SAR for subsurface de-arsenization was successfully tested in the Mekong Delta as part of the WaKap joint project (www.wakap.de).
The treatment of arsenic-containing groundwater is carried out as an oxidative in-situ treatment by regular infiltration of oxygen-enriched water into the aquifer. The oxygen is simply taken from the ambient air, and only electrical power is required as an operating medium.
After the first pilot phase in Vietnam, an arsenic elimination of > 97 % (from 80 µg/l to < WHO drinking water limit of 10 µg/l) could be achieved - besides an almost complete iron removal.
After about 2.5 years of operation under real conditions, the permanent arsenic removal could be confirmed by SAR to concentrations in the drinking water range.
The FERMANOX® prototype UEE/SAR is designed for easy use and suitable for export. On site, any tank can be connected and the feed pump (supplied or on site) can be docked. The design is for alternate operation with 2 delivery wells. The infiltration ratio (infiltration to extraction volume) is determined individually for each application from the raw water quality at the site. Therefore, depending on the raw water quality, the prototype has a treatment capacity of approx. 40 to 400 m³/day.