(575b) Light-Limited Continuous Culture of Micro Algae in a Taylor Vortex Reactor

Vigil, R. D. - Presenter, Iowa State University
Kong, B., Iowa State University

Recently, it has been demonstrated that Taylor vortices – hydrodynamic structures that arise in the annular region between two concentric cylinders when the inner cylinder rotates – can substantially improve the growth rate of algal biomass in a batch photobioreactor by inducing the flashing light effect. In order to assess the potential for using Taylor vortex flow to continuously culture algae, experiments were carried out in a continuous flow Taylor vortex algal photobioreactor using various microalgae. Two important operating parameters were varied: the dilution rate and the inner cylinder rotation speed. For a fixed inner cylinder rotation speed, biomass productivity decreased at low dilution rates but was constant at higher dilution rates. Biomass productivity was found to increase slightly with increasing inner cylinder rotation speed for a fixed dilution rate, and this weak dependence on rotation speed may indicate that the flashing light effect was nearly maximized even at the lowest cylinder rotation speeds employed. Overall, it is demonstrated that a continuous flow Taylor vortex algal photobioreactor can be used to produce and sustain high biomass production and carbon dioxide capture rates when operated in continuous flow mode.