Uploaded on Dec 30, 2014 – Toxic synthetic chemicals such as pesticides and pharmaceutical residues are a major threat to drinking water safety worldwide. Unfortunately, major international water development initiatives focus exclusively on microbial pathogens (the most immediate threat to health) while neglecting synthetic chemical toxins. Low-cost, environmentally sustainable and locally managed treatment technologies are needed to protect human health in impoverished, rural and remote communities.

Our ongoing research demonstrates the potential of char made from surplus biomass (biochar) as an effective sorbent for chemical toxins. We have shown that highly adsorbing biochar can be produced from surplus biomass using low-tech, efficient and environmentally friendly gasifier drum ovens. Our work advances sustainable and locally managed treatment systems employing adsorbent biochar as an effective, affordable and accessible means for providing drinking water that is microbiologically and chemically safe to households and communities in remote and impoverished regions of the world.

Synthetic organic water contaminants in developing communities: an overlooked challenge addressed by adsorption with locally generated char. Journal of Water, Sanitation and Hygiene for Development, Vol 4 No 3 pp 422–436 © IWA Publishing 2014 doi:10.2166/washdev.2014.073

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Joshua P. Kearns, Detlef R. U. Knappe and R. Scott Summers

Department of Civil, Environmental, & Architectural Engineering, University of Colorado-Boulder, 1111 Engineering Dr, ECOT 441, UCB 428, Boulder, CO 80309, USA E-mail: joshua.kearns@colorado.edu
Department of Civil, Construction, & Environmental Engineering, North Carolina State University, 2501 Stinson Dr, Campus Box 7908, Raleigh, NC 27695, USA

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, remote, and emergency/disaster relief/humanitarian crisis situations. Char filter-adsorbers have been used to treat drinking water for thousands of years and are still widely used today. Our studies show that some chars produced by traditional means from a range of feedstocks develop favorable sorption properties for uptake of 2,4-dichlorophenoxyacetic acid (2,4-D), a prevalent herbicide and water contaminant.

However, more energy efficient, environmentally sustainable and scalable production of consistent highly sorptive chars can be accomplished with biomass gasification. Our laboratory studies demonstrate that locally produced char adsorbents derived from surplus agricultural and forestry biomass are effective for adsorbing 2,4-D. A year-long study of field-scale application of chars in Thailand is also presented. Based on these studies we present design recommendations for integrating char adsorbers into low-cost, multi-barrier treatment trains for on-site water provision.

Synthetic organic water contaminants in developing communities: an overlooked challenge addressed by adsorption with locally generated char. Journal of Water, Sanitation and Hygiene for Development, In Press

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Joshua P. Kearns, Detlef R. U. Knappe and R. Scott Summers

Department of Civil, Environmental, & Architectural Engineering, University of Colorado-Boulder, 1111 Engineering Dr, ECOT 441, UCB 428, Boulder, CO 80309, USA E-mail: joshua.kearns@colorado.edu
Department of Civil, Construction, & Environmental Engineering, North Carolina State University, 2501 Stinson Dr, Campus Box 7908, Raleigh, NC 27695, USA

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, remote, and emergency/disaster relief/humanitarian crisis situations. Char filter-adsorbers have been used to treat drinking water for thousands of years and are still widely used today. Our studies show that some chars produced by traditional means from a range of feedstocks develop favorable sorption properties for uptake of 2,4-dichlorophenoxyacetic acid (2,4-D), a prevalent herbicide and water contaminant. However, more energy efficient, environmentally sustainable and scalable production of consistent highly sorptive chars can be accomplished with biomass gasification. Our laboratory studies demonstrate that locally produced char adsorbents derived from surplus agricultural and forestry biomass are effective for adsorbing 2,4-D. A year-long study of field-scale application of chars in Thailand is also presented. Based on these studies we present design recommendations for integrating char adsorbers into low-cost, multi-barrier treatment trains for on-site water provision.