Algae bioreactor for biodiesel production

Abstract

Biodiesel production and use are becoming more prevalent across North America and Europe as fueling stations become equipped with biodiesel pumps at a continually increasing rate. As petroleum reserves become depleted, the price of petroleum-based diesel will increase, while biodiesel prices are expected to decrease due to increased supply. Biodiesel is produced through transesterification of oils or fats and can be used in unmodified diesel engines. This makes biodiesel an ideal petroleum-based-diesel substitute as car manufacturers and consumers will not experience manufacturing cost changes. Algae are efficient for biodiesel production because they are about 50% by mass oil, which can be used to make biodiesel fuel. Algae can also grow in areas where other plants cannot be grown such as salt water or polluted areas. Additionally, algae grown near power plants will consume the emitted CO2 and use it for photosynthesis. This article reports the results of a student capstone design project, in which a small reactor for biodiesel production was built using a vertical design. It produced 1420 ml (48 fl. oz.) of algae, which resulted in a net production of 591 ml (20 fl. oz.) of lipid oil through refreezing the algae. We were able to produce 532 ml (18 fl. oz.) of biodiesel fuel in less than 11 weeks.