BIO_ALGAE 2: improved model of microalgae and bacteria consortia for wastewater treatment

• Published in: Environmental science and pollution research international 2019-09, Vol.26 (25), p.25855-25868
• Main Authors: Solimeno, Alessandro, Gómez-Serrano, Cintia, Acién, Francisco Gabriel
• Format: Article
• Language: English
• Subjects: Algae; Aquatic microorganisms; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Bacteria; Carbon dioxide; Composition; Computational fluid dynamics; Computer simulation; Consortia; Correlation analysis; Dissolved oxygen; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Fluid flow; Hydrodynamics; Injection; Mass transfer; Microalgae; pH control; pH effects; Reactors; Research Article; Waste Water Technology; Wastewater composition; Wastewater treatment; Water Management; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-019-05824-5

A new set up of the integral mechanistic BIO_ALGAE model that describes the complex interactions in mixed algal-bacterial systems was developed to overcome some restrictions of the model. BIO_ALGAE 2 includes new sub-models that take into account the variation of microalgae and bacteria performance as a function of culture conditions prevailing in microalgae cultures (pH, temperature, dissolved oxygen) over daily and seasonal cycles and the implementation of on-demand dioxide carbon injection for pH control. Moreover, another aim of this work was to study a correlation between the mass transfer coefficient and the hydrodynamics of reactor. The model was calibrated using real data from a laboratory reactor fed with real wastewater. Moreover, the model was used to simulate daily variations of different components in the pond (dissolved oxygen, pH, and CO 2 injection) and to predict microalgae ( X ALG ) and bacteria ( X H ) proportions and to estimate daily biomass production ( C b ). The effect of CO 2 injection and the influence of wastewater composition on treatment performance were investigated through practical study cases. X ALG decreased by 38%, and X H increased by 35% with respect to the system under pH control while microalgae and bacteria proportions are completely different as a function of influent wastewater composition. Model simulations have indicated that C b production (~ 100 gTSS m −3  day −1 for manure and centrate) resulted lower than C b production obtained using primary influent wastewater (155 gTSS m −3  day −1 ).