Over winter break 2017, two undergraduate students, three graduate students, a professor, and some cookstove experts gathered to perform testing on a new cookstove-powered pasteurization system to see if it could effectively disinfect drinking water contaminated with e.coli and other disease-causing organisms. Today 1 in 10 people do not have access to clean drinking water and three billion people around the world still use traditional methods such as open biomass campfires to cook food or boil their water to purify it. This creates many problems for the user: health issues from inhaling the smoke, a high cost of using so much wood, and a safety risk for women who must travel farther and farther out of the safety of their camps or homes to get wood for their fires. Many refugee camps have little high concentrations of people with little access to wood or other fuel for fire. The extreme nature of the camp population puts stress on an area’s systems which are pushed to provide food and water. Boiling water for this dense population requires a great deal of time and human effort. Emissions from the process of cooking and cleaning water and deforestation are also harming the environment; in turn, the food sources are put at risk.
To solve these issues, the nonprofit InStove (the designer of the Institutional Rocket Stove verified by USAID to be the most advanced in its category in the world) created a cookstove and pasteurization system that reduced the amount of wood needed by 97%, directs the smoke away from the user through a chimney, and would, hopefully, be able to pasteurize water. Pasteurization heats water to a lower temperature (71°C) rather than boiling (100°C) and is therefore more efficient. The pasteurization system could produce 6,000 liters of clean drinking water a day if proven to effectively clean water.
Mechanical engineering students and faculty from Oregon State University conducted tests with advisors from InStove to see if these cook stoves could be used not only for cooking in low resource environments, but also to effectively and efficiently clean water. In these tests, a large amount of water was inoculated with E.coli, pumped into the stove, heated, and was then extracted into a clean container. The water was tested throughout the process to see how much E.coli was present.
Water was pumped up to this container and down to the stove
The container the stove dispensed the water into (blue)
E.coli concentrations before and after pasteurization
Three tests were conducted and they were all successful; the water started with a high concentration of E. coil and exited the stove with no E. coli present. With this information, the InStove can now go through the process of implementing these stoves around the world in places that need high quantities of clean drinking water such as refugee camps, schools, or hospitals. With only a pencil weight of fuel wood used to generate a liter of potable water, there is no other solid fuel water pasteurization system like this in the world today. It was great to be a part of this discovery and innovation in water pasteurization technology that can allow people around the world get clean water with more ease.