Trace organic contaminant removal from drinking water using local char

Chemical contamination of drinking water sources is a worldwide problem. However, few locally managed, sustainable, and low-cost on-site treatment technologies are available in rural and remote situations. Char filter-adsorbers have been used to treat drinking water for thousands of years and are still widely used today. Our laboratory studies have shown that chars derived from surplus agricultural and forestry biomass using low-cost, low-emission gasifier cookstoves and drum-ovens develop favorable sorption properties for uptake of prevalent organic contaminants such as 2,4-D herbicide, environmentally persistent pharmaceuticals sulfamethoxazole and warfarin, algal metabolite 2- methylisoborneol, and trihalomethane by-products resulting from chlorine disinfection. Based on these studies we present design recommendations for integrating char adsorbers into low-cost multi-barrier treatment trains for on-site water provision. We also present field observations and monitoring data from application of char adsorbers in Thailand and eastern Burma.