Microalgal Biodiesel Production through a Novel Attached Culture System and Conversion Parameters

Using algae as a feedstock for biodiesel has been considered for a number of years, but it has always had limitations, due mainly to the production methods used to grow and harvest the algae. In this project, we propose a novel attached growth method to produce the algae while recycling dairy farm wastewater using the microalga Chlorella sp. The first part of the work provided a feasibility study of attachment of the alga onto the supporting material as optimizing parameters for the algae to be grown on wastewater. The results showed that wastewater filtered through cheesecloth to remove large particles was feasible for production of Chlorella sp, with pure wastewater producing the highest biomass yield. The algae were able to produce more than 3.2 g/m-day with lipid contents of about 9% dry weight, while treating dairy farm wastewater and removing upwards of 90% of the total phosphorus and 79% of the total nitrogen contained within the wastewater. Rather than focus solely on biomass production, in the second part, we looked into biodiesel creation methods as well. Biodiesel is created through a chemical reaction known as transesterification. By simplifying the reaction conditions and pretreatment operations, while examining the effects in terms of maximum fatty acid methyl esters (FAME) produced, we were able to determine that a direct transesterification with chloroform solvent was more effective than the traditional extraction-transesterification method. This synergistic research helps to create a more complete picture of where algal biodiesel research and development is going in the future.