Washington: A US researcher has come up with a proposal to develop a simple sewage disposal system for Third World countries, which will not only dispose off waste but also work without using any electricity or additional energy to destroy harmful germs.
For less than 100 dollars and a day’s work, a single family in an undeveloped country can construct this solid waste disposal system.
Marc Deshusses, professor of civil and environmental engineering at Duke’s Pratt School of Engineering, has plans to develop a novel sewage digestion system with capture of the methane gas produced during the breakdown of the waste to produce enough heat to kill the bacteria and viruses most commonly associated with human waste.
The Bill and Melinda Gates Foundation, an organization that works to help all people lead healthy and productive lives, believes that Deshusses’s idea has promise.
The foundation’s Grand Challenges Explorations program granted Deshusses 100,000 dollars to move his ideas from the laboratory to field-testing in 18 months.
“People in countries that lack proper sanitation for their sewage desperately need a disposal method that is cheap, simple to implement and maintain, and reliable,” Deshusses said.
“We believe the proposed system could represent a major advance in environmental and health protection for developing countries.”
In the system designed by Deshusses, the waste would be directed to a chamber, likely constructed of PVC pipe.
Once sealed in the chamber to create an oxygen-free, or anaerobic, environment, bacteria digests the waste.
As a byproduct of this digestion, methane gas is produced.
“The system works much like septic tanks used in many rural communities,” Deshusses said.
“However, in septic tanks, the methane produced is released into the environment, which a lost opportunity as well as an environmental liability. As a greenhouse gas, methane is 25 times more potent than carbon dioxide.”
But instead of letting the methane escape into the environment, the new approach captures it and burns it, creating enough heat to kill pathogens in the effluent.