Page 5 - 2013 ANNUAL REPORT : The EARTH effect

As part of their Graduation Projects, students Rui Madime (’13,Mozambique, left), Jesús Castrezana
(’13, Mexico, center), Jorge Ferraté (’13, Guatemala) and Rodrigo Kohlmann Reyes (’13, Mexico,
right) developed a dry anaerobic reactor or bio-digester that converts organic kitchen waste into
biogas.The students fed the reactor every day with leftover Gallo Pinto, a traditional Costa Rican
breakfast dish of beans and rice, from the University’s cafeteria. In the closed system, methane-
producing bacteria flourish as the leftovers decompose. The reactor is intended to be installed in
industrial or restaurant kitchens, is odorless and provides a renewable source of fuel for gas stoves.
“The reactor itself taught us a lot. We had a design on paper, but once it was built and functioning we had
to make a lot of modifications,” explains Rui.
Rui and Jesús both have plans to apply the design in their respective countries. For his part, Rui
plans to remain in touch with his classmates in order to patent a prototype and seek financing
for the project’s implementation in Mozambique. Jesús is also planning to apply the project in his
family’s business in Mexico, which includes a farm, processing plant and restaurant.
© Lynn Hoffman-Brouse for EARTH University