A Better ToiletFor A Cleaner World
Duke University Center for WaSH-AID
Integrated Waste Treatment System
2.4 billion people live without improved sanitation (World Health Organization (WHO)/UNICEF 2015).
One in ten people has no choice but to defecate in the open (WHO/UNICEF 2015).
Diarrhea caused by poor sanitation and unsafe water kills 315,000 children every year (WASHwatch 2016).
Disease transmission at work, mostly caused by poor sanitation and hygiene practices, causes 17% of all workplace deaths (International Labour Organization (ILO) 2003).
Loss of productivity due to illnesses caused by lack of sanitation and poor hygiene practices is estimated to cost many countries up to 5% of GDP (Hutton 2012).
- Duke University and its partners are developing a toilet that converts human waste into burnable fuel, stored energy and disinfected, non-potable water
- Novel waste treatment system could help improve public health and quality of life among people in developing nations
- The system will not require piped-in water, a sewer connection or outside electricity
This novel toilet accomplishes three primary functions: disinfect liquid waste, dry and burn solid waste, and convert the resulting combustion energy into stored electricity. The system also includes innovations to improve operational utility, energy efficiency and cost.
The processing of the solid waste will use a combination of mechanical and thermal energy. A mechanical conveyor belt separates and diverts liquid waste while transporting solid waste to a series of components that blends it into a uniform material, extrudes it onto a drying plate, then burns the dried pieces using a novel combustion unit designed by our partners at Colorado State University. This self-powered unit not only provides heat for the plate-drying process, but converts a portion of the heat into electricity to power the processing of liquid waste.
Liquid waste—including urine and liquid that is removed from the solid waste—will be disinfected through electrochemical processes using carbon electrodes. The disinfected water will be suitable for use as rinse water for the toilet or as a fertilizer supplement.