Design of raceway ponds for producing microalgae

Background: A raceway pond for producing algal fuels must be designed to minimize the energy required for mixing, otherwise the net energy recovery in the biofuel will be low. Results & discussion: Computational fluid dynamics modeling was used to characterize the energy demands for mixing full-scale raceways of various configurations. The locations of the dead zones and the conditions required for eliminating them were identified. The existing geometric configurations of the raceways were compared, to identify the best configuration. Conclusion: An inexpensive raceway configuration with a minimum of three semicircular deflector baffles and a modified end of the central divider was found to be the most energy efficient, while also being able to completely eliminate the dead zones.