Why is the Penn State Biodiesel Research Group not using a centrifuge to speed up the biodiesel/glycerin separation?
In the current process used by the research group, the separation of biodiesel and glycerin is achieved through the simple use of a large separatory funnel and gravity. Our current benchmark practice of this separation takes 2 to 10 times as long as the rest of the biodiesel production process combined. The reason for the continuation of our current practice is in the interest of energy efficiency and production sustainability. According to the National Energy Renewable Laboratory (NREL), biodiesel can produce 3.2 times the energy that it consumes in its life and production cycle. If a large centrifuge were used (capable of separating roughly 100 gallons of product per day), in which the bidiesel and glycerin would be horizontally suspended by spinning multiple tubes at over 1,000 rpm, a lot of energy would be wasted. In addition, the possibility of production failure and delay would increase along with the maintanence demand of the complex workings of the large-scale centrifuge. It is
