Acta Bot. Sin.

The growth behavior, photosynthetic productivity and carbon utilizing characteristics of filamentous cyanobacterium Spirulina platensis Geitler were investigated in continuous cultures in a 10 L internalloop airlift photobioreactor. It was found that the cell density and the amount of carbon in the reactor increased and decreased with dilution rate respectively, and the relationships among them could well be expressed by the modified Monod equation. When dilution rate was 0.45/d, the rate of cell growth and that of carbon assumption reached their maximum points 0.362 g/(L.d) and 0.177 g/(L.d) respectively. The cell growth yield against carbon was 2.050 g/g. The proposed model of continuous growth fitted the experimental data quite well.The growth behavior, photosynthetic productivity and carbon utilizing characteristics of filamentous cyanobacterium Spirulina platensis Geitler were investigated in continuous cultures in a 10 L internalloop airlift photobioreactor. It was found that the cell density and the amount of carbon in the reactor increased and decreased with dilution rate respectively, and the relationships among them could well be expressed by the modified Monod equation. When dilution rate was 0.45/d, the rate of cell growth and that of carbon assumption reached their maximum points 0.362 g/(L.d) and 0.177 g/(L.d) respectively. The cell growth yield against carbon was 2.050 g/g. The proposed model of continuous growth fitted the experimental data quite well