Línea base para el aprovechamiento de microalgas de sistemas de tratamiento de agua residual

Abstract

The rapid reduction of fossil fuel reserves has encouraged the research and development of new energy technologies with lower impact to the environment during the last decades. Today, the research on biofuel produced through transesterification of microalgae lipids extracted with a neutral carbon footprint, has shown a vast potential. In this research, five different families of microalgae were cultured: Chlorella, Scenedesmus, and three isolated but unidentified families. Growth rates determination was performed using the chlorella family by cell count techniques. The growth rate obtained was 0.022 h-1during the exponential phase of growing. A respirometertechnique at laboratory scale was implemented to investigate the rate of biomass oxygen consumption under controlled conditions. Besides, experimental protocols for the production of lipids with the purpose of producing biofuels was tested. Different solvents such as methanol, chloroform, hexane, ethanol and acetone were used, obtaining lipid and chlorophyllmixed content in the algae cells from 5.2 to 23.7% of the dry cell weight,depending on the solvent used. The nutrient removal efficiency of microalgae was alsoassessed, verifying the high capacity of microalgae to incorporate into their cell composition nitrogen and phosphorus during the exponential cell growth. The latest, confirms the high potential of microalgae cultures in nutrient rich environments like the domestic wastewater, helping on the removal of organic matter and also bringing a sustainable practice by means of the energy recovery from their cell composition.