MICROALGAE ENERGY TECHNOLOGIES: RENEWABLE BIOMASS PRODUCTION FOR BIOFUELS, BIOENERGY AND BIOPRODUCTS

Ryan Hunt, research staff member at the Biorefinery and Carbon Cycling Center, with the Sartorius Biostat small scale photo bioreactor. Sartorius Biostat specs >> See Ryan Hunt's poster (with S. Chinnasamy and K.C. Das) "Microalgae Mediated Biodiesel Production Using Poultry Litter" presented at the 2007 Sunbelt Agricultural Exposition. Powerpoint file >> See K.C. Das's poster "Microalgae Bioenergy Technology: An Integrated Approach to Biofuel Production" presented at the 2007 Sunbelt Agricultural Exposition. Powerpoint file >> Microalgae growth chamber Microalgae laboratory Bioconversion and Microalgae Group

Biodiesel is a promising alternative to the petroleum-based energy production. There are two steps that would need to be taken for producing biodiesel on a large scale—growing the feedstock, and processing them into biodiesel. The main issue that is often contested is whether or not we would be able to grow enough crops to provide the vegetable oil (feedstock) for producing the amount of biodiesel that would be required to completely replace petroleum as a transportation fuel.

In addition, one of the important concerns about wide-scale development of biodiesel is if it would displace croplands currently used for food crops. At heart, biofuels are a form of solar energy, as plants use photosynthesis to convert solar energy into chemical energy stored in the form of oils, carbohydrates and proteins.

The more efficient a particular plant is at converting that solar energy into chemical energy, the better it is from a biofuels perspective. Among the most photosynthetically efficient plants are various types of algae, abundantly available in many ecosystems. Among the diverse algae, the aquatic microalgae are one of the efficient organisms in the use of photo-energy for biomass production.

Aquatic microalgae can use sunlight, nutrients in wastewater and CO₂ from waste flue gases and fermentation off gases to produce biomass rapidly and efficiently. As the potential benefits are enormous, research focus on algal production using waste streams and CO₂ emissions need a high priority.

RESEARCH OBJECTIVES

• To propose a combined biotechnological scheme for processing/treatment of agricultural and industial waste streams such as wastewater and flue gases for production of microalgae.
• To examine the algal growth and lipid content under various carbon dioxide concentrations, nutrient levels, temperature, light intensity and salinity conditions for determining the optimal growth conditions for enhanced biomass production
• To develop cost-effective large-scale open/closed photobioreactors.
• To develop technologies for harvesting algal cells and extraction and conversion of lipids/ biohydrocarbons into biodiesel or bio-oil
• To develop technologies for production of biodiesel or bio-oil or other biofuels such as ethanol and methane from microalgae through processes like fermentation, thermochemical liquefaction, gasification and pyrolysis
• To conduct LCA and technical and economic analysis of photobiological production of algae biomass as feedstock for renewable energy and fuel production