A Duke environmental engineer will apply a recently received grant to safely eliminate biowaste in underdeveloped countries.
Marc Deshusses, professor of civil and environmental engineering at the Pratt School of Engineering, received a $100,000 grant from the Grand Challenges Exploration program of the Bill and Melinda Gates Foundation to develop a novel human waste disposal system specially designed for families in developing countries.
Deshusses designed a system where human and animal waste is decomposed by bacteria in a sealed space. The design captures the biogas produced during the process and burns it as fuel to provide enough heat to kill dangerous pathogens associated with human waste. The mechanism will be produced from very affordable materials, Deshusses noted, estimating that the whole system will cost less than $100 for a single family.
“Once constructed, the system runs automatically.... People do not need additional skills to operate it,” Deshusses said. “The goal is to investigate the science and technology to make sure we come up with the solution adapted to developing countries.”
For many developing countries, the removal of human waste poses a major public health risk—poorly disposed of waste can contaminate drinking water and spread disease. David Schaad, associate professor of the practice of civil and environmental engineering at Pratt and co-investigator of the innovative waste digestion system, said the new idea could effectively address those problems.
“One in three people in the world lack access to improved sanitation.... This novel enhancement, if successful, could remove pathogens, increase health outcomes and elevate the standard of living for potentially millions of people around the world,” Schaad wrote in an email Monday.
The system is environmentally friendly because the methane gas produced during biochemical reactions would not be released into the environment, preventing a potent greenhouse gas from entering the atmosphere, Deshusses said.
“The originality of the whole concept is that we do a heat recovery system,” he said. “In the traditional devices the heat [of burning biogas] is not enough, but here is our ‘trick’—the heat recovery can ensure that the heat is used with little dissipation.”
Deshusses also noted the importance of the system’s dependability.
“To ensure safety and reliability, there will be no moving parts and the whole system is totally based on gravity,” Deshusses said. “Gravity never fails.”
The research is still in its starting phase. Deshusses plans to spend about a year refining the design and enhancing its performance. Nine months after that, he will produce a prototype to test in the laboratory and in the field. Deshusses said he might explore a partnership with the DukeEngage program in Honduras if the test results are promising.
If field tests prove successful, more installations will be set up across the world, he added.
George Truskey, chair of the department of biomedical engineering, thought the project is promising but still has to face many challenges before being functional for ordinary households.
“It could have widespread application, addressing not only issues about human waste processing in underdeveloped countries but also problems regarding livestock waste in our country,” Truskey said. “But there would be lots of challenges along the way, such as cost, manufacturing quality and safety.”
Truskey said that the atmosphere of interdisciplinary collaboration at Duke would be a facilitator for Deshusses to realize his goal.
“Duke has experts of nearly all health-related issues who are really helpful,“ Truskey said. “If [Deshusses] faces some difficulties—for example, questions about infectious disease—he does not need to contact someone a thousand miles away. His colleagues are always ready to help.”
The Grand Challenges Exploration program of the Bill and Melinda Gates Foundation is a $100 million initiative rewarding innovative ideas that aim to confront global health challenges. It has awarded grants to 603 researchers from 44 countries, according to the program’s website.