Reducing Energy Costs of a Microalgae Pilot Scale Cultivation Bubble Column Photobioreactor via Critical Adjustments in Airflow Rate

An unavoidable replacement of the unsustainable fossil fuel industries may rely on bioenergetic solutions from vegetables biomass. Microalgae biomass derived fuels needs to maximize production with minimal energy input to cultivation and harvesting operations. The mixing/circulation comprises an essential step in the expensive microalgae cultivation process. Additionally, prevent cell settlement and increases exposure to light and nutrients. Nevertheless, is responsible for at least one-third of total cost to produce lipid from microalgae. Properly regulating the air input endures an effective way to save energy, but can compromises production. Pilot scale photobioreactors with different airflow rates (treatments) for production of the marine microalgae Nannochloropsis oceanica were used to properly evaluate the most energy efficient adjustment. The airflow rate of 0.0024 vvm presented a satisfactory production and low energy input. From the practical experiments the highest Energy Return On Investment value was observed also in this airflow rate.