Understanding the biological activity of high rate algae ponds through the calculation of oxygen balances.
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.
FCC aqualia, EDAR El Torno, C/Polígono Industrial El Torno, s/n, 11130, Chiclana de la Frontera, Cádiz, Spain.
Zouhayr
Z
Arbib
IMDEA Energy, Avda. Ramón de la Sagra, 3, 28935, Móstoles, Madrid, Spain. ignacio.degodos@imdea.org.
Ignacio
I
de Godos Crespo
FCC aqualia, P.Ind. Nuevo Calonge C/Pincel 25, 41005, Sevilla, Spain.
Enrique Lara
EL
Corona
FCC aqualia, Avda. del Camino de Santiago, 40 Edif. 3 Plta. 4, 28050, Madrid, Spain.
Frank
F
Rogalla
D018533:Biomass; D019149:Bioreactors; D008027:Light; D058086:Microalgae / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010788:Photosynthesis; D061005:Ponds / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods
D010100:Oxygen
Microalgae; Oxygenation potential; Photosynthetic rate; Raceways/high rate algae ponds