Understanding the biological activity of high rate algae ponds through the calculation of oxygen balances

• Published in: Applied microbiology and biotechnology Vol. 101; no. 12; pp. 5189 - 5198
• Main Authors: Arbib, Zouhayr, de Godos Crespo, Ignacio, Corona, Enrique Lara, Rogalla, Frank
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-06-2017; Springer; Springer Nature B.V
• Subjects: Algae; Aquatic microorganisms; Atmosphere; Atmospheric models; Balances (scales); Biological activity; Biomass; Biomedical and Life Sciences; Bioreactors; Biotechnology; Clean technology; Climate; Climatic conditions; Dilution; Dynamical systems; Environmental Biotechnology; Environmental protection; Exchanging; Irradiance; Life Sciences; Light; Light intensity; Load distribution; Loading rate; Luminous intensity; Microalgae; Microalgae - metabolism; Microbial Genetics and Genomics; Microbiology; Optimization; Organic loading; Oxygen; Oxygen - metabolism; Oxygen consumption; Oxygen production; Oxygenation; Photosynthesis; Physiological aspects; Ponds; Ponds - microbiology; Solar radiation; Stability; Systems analysis; Waste Disposal, Fluid - methods; Wastewater treatment; Water treatment; Oxygenation potential; Photosynthetic rate; Microalgae; Raceways/high rate algae ponds
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-017-8235-3

Microalgae culture in high rate algae ponds (HRAP) is an environmentally friendly technology for wastewater treatment. However, for the implementation of these systems, a better understanding of the oxygenation potential and the influence of climate conditions is required. In this work, the rates of oxygen production, consumption, and exchange with the atmosphere were calculated under varying conditions of solar irradiance and dilution rate during six months of operation in a real scale unit. This analysis allowed determining the biological response of these dynamic systems. The rates of oxygen consumption measured were considerably higher than the values calculated based on the organic loading rate. The response to light intensity in terms of oxygen production in the bioreactor was described with one of the models proposed for microalgae culture in dense concentrations. This model is based on the availability of light inside the culture and the specific response of microalgae to this parameter. The specific response to solar radiation intensity showed a reasonable stability in spite of the fluctuations due to meteorological conditions. The methodology developed is a useful tool for optimization and prediction of the performance of these systems.