A Project Developing a Process for Sustainable Low Cost Biofuel and Biochar for Rural West Africa

A Project Developing a Process for Sustainable Low Cost Biofuel and Biochar for Rural West Africa

The motivation for this project came from the need to develop affordable energy technology to develop biodiesel and biochar in developing countries.  Cameroon, Africa is an example of such a country. Most of the villages in Cameroon are without consistent sources of reliable power. Therefore, being able to produce even such small amounts of biodiesel as that needed to power a tractor or generator can make a huge difference in one village. This summer when my research team and I traveled to the village of Bangang in Cameroon Africa we were able to see this difference first-hand. Our group of chemical and mechanical engineering students embarked on a ten-day visit to implement an engineering service-based project to develop appropriate, sustainable biodiesel and biochar technology for use by local villagers.  Poverty and rapid population growth have led to the accelerated destruction of natural resources throughout West Africa. The purpose of this project was not only to help introduce the concepts of sustainability, service-based learning and appropriate technology, but also to help take under utilized natural resources and turn them into a type of energy that could be used efficiently.

Some of the raw materials used were locally available feedstock and construction materials. The vegetable oil needed to produce biodiesel is available in tropical regions in abundant supply.  Additional raw materials such as methanol or ethanol and a base catalyst such as sodium hydroxide or potassium hydroxide are also required.  This presents a special challenge since these raw materials are typically unavailable to rural people in the tropic. When our team was in Africa methanol was not available. As a substitute we used 49% gin, which made the process more time consuming by having to wash the 51% water out of the biodiesel. Another product that was not available was sodium hydroxide, which is the catalyst for the biodiesel. The substitution made was calcium hydroxide. The substitutions made the process more challenging but still efficient.

The reactors were constructed from using 35-gallon metal drums for the biodiesel or biochar production. This design was built to be a portable, safe, simple and efficient system.  We created a kiln to heat both reactors, instead of making two totally separate processes. This not only saved time but money as well, increasing our efficiency. For the biodiesel reactor one of the gasses released during the process is methanol, so we used a car radiator to recycle the methanol back into the reaction. We devised a similar process with the biochar system, using the gas released in this process, char, to recycle into the wood firebox refueling the fire, again increasing our efficiency.