Performance of a flat panel reactor in the continuous culture of microalgae in urban wastewater: Prediction from a batch experiment

• Published in: Bioresource technology 2013-01, Vol.127, p.456-463
• Main Authors: Ruiz, J., Álvarez-Díaz, P.D., Arbib, Z., Garrido-Pérez, C., Barragán, J., Perales, J.A.
• Format: Article
• Language: English
• Subjects: Applied sciences; biodiesel; Biological and medical sciences; Biological Oxygen Demand Analysis; Biomass; biomass production; Bioreactors; Carbon dioxide; Carbon Dioxide - metabolism; carbon dioxide fixation; Cell Culture Techniques - methods; Cities; Continuous culture; Exact sciences and technology; Flat panels; Fundamental and applied biological sciences. Psychology; gas production (biological); Kinetics; Mathematical models; Maximization; microalgae; Microalgae - growth & development; Microalgae - metabolism; Nitrogen - metabolism; Nutrient removal; nutrient uptake; Nutrients; Phosphorus - metabolism; photobioreactors; Pollution; prediction; Reactors; Regression Analysis; Scenedesmus - growth & development; Scenedesmus - metabolism; Scenedesmus obliquus; specific growth rate; Time Factors; Urban wastewater; Waste Disposal, Fluid - methods; Waste water; Waste Water - microbiology; wastewater; Wastewaters; Water treatment and pollution
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2012.09.103

► We grow Scenedesmus obliquus in urban wastewater in batch and continuous operation. ► Biomass in continuous operation can be predicted based on batch growth kinetics. ► Optimum operation residence times are based on specific growth rate from batch. ► Optimum hydraulic retention time depends on the objective of the culture. A laboratory-scale flat panel photobioreactor was operated for the continuous growth of Scenedesmus obliquus and consequent removal of nutrients in wastewater. This study develops a simple model by which biomass values in continuous operation can be predicted from kinetic growth parameters obtained from a shorter batch experiment. Based on this study, biomass concentrations and productivities in continuous operation can be successfully predicted as a function of the specific hydraulic retention time (HRT) assumed. Considerable biomass production and nutrient uptake from wastewater were achieved in the experiment. Optimum operating conditions for the reactor depend on the particular objective: the maximization of biomass production and carbon dioxide biofixation involves a HRT of 2μ−1 (specific growth rate), whereas efficient nutrient removal involves a HRT as close as possible to μ−1 (as long as discharges comply fully with the parameters set); alternatively biomass intended for biodiesel or biogas production would involve a HRT>2μ−1.