(318d) Bioreactor Process Model for Microalgae Production Systems

Microalgae are a promising feedstock for production of fuels and value-added chemicals. In order to assess the economic, energetic and environmental performance of algae based system in an industrial scale biorefinery, it is important to model algae productivity accurately.  In this work, a first principle based growth model of microalgae biomass and lipid production is developed for an outdoor pond system. The primary factors that affect microalgae growth and accumulation of lipids, such as solar irradiance, temperature, specific characteristics of species, uptake rates of nutrients and carbon dioxide, are incorporated in the bioreactor process model.  Year-round algae productivity potential is computed taking into the seasonal effects on microalgae growth. As there are significant uncertainties associated with the different parameters of the growth model, detailed sensitivity analyses are performed. Results show that solar irradiance and maximum specific growth rate are the most significant parameters in microalgae bulk growth. Results from the dynamic model can be used to optimize and scaling up of algae systems for efficient production of fuels and chemicals for variety of algae species as well as geospatial locations.