The reuse of wastewater resources via micro-algal cultivation is a cost-effective and sustainable solution for third generation biofuel production. A process model, describing photobioreactor operation – also in combination with activated sludge processes, however, is still missing. In this paper, we present a mathematical model, accounting for photoautotrophic and heterotrophic algal growth, nutrient uptake and storage in a mixed microalgae culture cultivated on nutrient rich carbon depleted (NRCD) wastewater. The process model is developed as an extension to the Activated Sludge Model 2d, ASM2d (Henze et al., 1999), and thus it also accounts for bacterial growth in the photobioreactor. We assess the factors, influencing algae growth and nutrient uptake, including macro-nutrient availability and light irradiance rate. Model parameters were estimated through microplate screenings and a series of batch experiments using a mixed green microalgal culture isolated in a wastewater pond, growing strictly in suspension.
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86th Annual Water Environment Federation Technical Exhibition and Conference (WEFTEC 2013)