Poop Bio-reactor to Generate Biogas

Kenyan student convert's school's poop into safe, clean fuelthe system is" an underground chamber holds the human, animal, and kitchen excrement, while microorganisms go to work breaking down the muck. This process releases biogas, a source of renewable energy

Kenya's oldest English-language school, theMaseno School, opened new dormitories for 720 students, and it had a couple of problems. Pit latrines and a faulty sewage system inevitably left foul odors and polluted local freshwater sources, while the kitchen used firewood for cooking fuel—unhealthy for cooks and the environment alike. So, asGristreports, Leroy Mwasaru, now 17, and four of his friends had an idea: to harvest poo and other waste and turn it into a safe, clean and eco-friendly source ofcooking fuel.

What Mwasaru and his friends proposed was to build a Human Waste Bioreactor (HWB) that would harvest not only the waste from all the students in the dorm, but also organic waste from the kitchen, cow dung and slashing grass to create biogas for cooking fuel. AsGristexplains, the HWB is "an underground chamber holds the human, animal, and kitchen excrement, while microorganisms go to work breaking down the muck. This process releases biogas, a source ofrenewable energycomprised mostly of methane, the same as the fossil fuel natural gas that powers most non-electric stoves in the U.S. The gas is contained in the HWB, ready for use as fuel."

And with this idea in mind, Mwasaru set about generating support and backing for the HWB. The team was accepted to theInnovate Kenyacamp this summer, where they were able to refine their design with the help of MIT students. By the fall the team had a working prototype and enough funding to purchase a plastic biodigester for the second iteration of the HWB.

Last month Mwasaru presented at theTechonomy 2014conference in California, and gained even more ideas to develop and refine the HWB design. Speaking to Grist, Mwasaru explained "After the success of our second prototype, we have been hands on, working on designing a human waste bioreactor toilet that separates urine from [the] solid part, stool, since urine will lower the rate of gas production or, worse still, stall the whole process."

The final version of the HWB will cost around 7 million Kenyan Shillings ($85,000) to build and install, but Mwasaru estimates that it will cut the school's cooking fuel costs in half while providing numerous benefits for the health of the local community and environment. After that? Mwasaru hopes to turn the project into it's own company, charging customers according to their ability to pay, so as to provide clean fuel and sanitation services to poor or off-the-grid communities.

Source : Inhabitat.com

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