| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 3396 | Biochemical Engineering Journal | 2013 | 7 Pages |
Indoor cultures of Stichococcus bacillaris were carried out to investigate the effect of pH, CO2, and hydrodynamics on biomass and biodiesel productivity in a 0.6 L vertical bubble column (VBC) and a 1.7 L inclined bubble column (IBC) photobioreactor. The temperature and the irradiance level were set at 23 °C and 300 μE/(m2 s), respectively. The pH of the liquid culture was in the range 3.0–8.5. The CO2 concentration in the gas phase was increased up to 15%, typical of exhaust gas from power plants. The increased CO2 concentration in the gas phase stimulated the microalgal growth. Tests carried out at different pH and spreading a 5% CO2 gas stream showed that the biomass productivity was maximum at a pH of about 7.0. Acid and alkaline conditions can also be adopted with an approximate 25% decrease in biomass productivity. The comparison between a IBC and a VBC reactor operated under the same conditions pointed out that the performances of IBC were higher than those of VBC: 0.26 gbiomass/(L d) and 0.032 gFAME/(L d) for IBC, and 0.124 gbiomass/(L d) and 0.010 gFAME/(L d) for VBC. IBC was characterized by an intensive liquid circulation that promotes a continuous renewal of microalgal cells in the photic zone.
► Autotrophic cultures of Stichococcus bacillaris were carried to produce biodiesel. ► Two photobioreactor configurations were investigated. ► Effects of pH, CO2 concentration and hydrodynamics were investigated. ► Biomass and FAME productivity were optimized: 0.26 g/(L d) and 0.032 g/(L d).
