Cultivation of Scenedesmus dimorphus for C/N/P removal and lipid production

Background: CO₂ emission,water pollution and petroleumshortage are the issues comingwith the development of industry. A cost effective system was constructed to fix the CO₂ in flue gas (15% CO₂), remove nitrogen and phosphorus from manure wastewater and produce biofuels at the same time. The significant cultivation conditions were selected by Plackett–Burman design, and then optimized with central composite design.
Results: Optimum culture condition was predicted at light intensity of 238 μmol·m^-2·s^-1, TN of 152 mg·L^-1, inoculum density of 0.3 g·L^-1, under which the measured CO₂ fixation rate, total nitrogen and phosphorus removing rate, and lipid content were 638.13 mg·L^-1·d^-1, 88.16%, 73.98% and 11.9%, respectively. The lipid content was then enhanced to 24.2% by a nitrogen starvation strategy.
Conclusion: A cultivation strategy was suggested to achieve effective C/N/P removal from flue gas and manure wastewater, and meanwhile obtained high lipid content from microalgal biomass.

Keywords
CO₂ fixation rate; Flue gas; Lipid content; Scenedesmus dimorphus; Wastewater