(480b) Modeling and Dynamic Optimization of Algal Biomass Production in an Open Pond

Successful implementation of algal biotechnology for the production of biofuels requires finding economical algal biomass production techniques. The commonly used open ponds are currently the most economic option for algae production. These ponds are exposed to the environmental conditions which greatly affect the growth rate of algae. Therefore, optimization becomes necessary for finding the optimal operating parameters that would lead such a complex biological system toward maximum productivity.

In this work, a model was developed to estimate the productivity of algae in an outdoor open pond. The factors considered in the model are the effects of nutrients, CO₂, and oxygen concentrations as well as the real local environmental conditions including irradiation, air temperature, and wind speed. The model was validated with experimental results from algae production in an outdoor open pond in Málaga, Spain. The developed process model was used in performing nonlinear dynamic optimization to find the optimal daily operations that maximize the annual algal biomass production. Such operations optimized include algae harvest rate, CO₂ bubbling flowrate, water depth, and nutrients addition. The software used for conducting the modeling and optimization is gPROMS®.