Periodic CO2 Dosing Strategy for Dunaliella salina Batch Culture

• Published in: International journal of molecular sciences Vol. 16; no. 5; pp. 11509 - 11521
• Main Authors: Ying, Kezhen, Gilmour, D James, Zimmerman, William B
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 19.05.2015; MDPI
• Subjects: Algae; Batch Cell Culture Techniques; Biomass; Carbon Dioxide; Chlorophyta - metabolism; CO2 capture efficiency; D. salina; dosing interval; dosing time; periodic CO2 dosing; Studies; dosing time; CO2 capture efficiency; dosing interval; D. salina; periodic CO2 dosing
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms160511509

A periodic CO2 dosing strategy for D. salina 19/30 batch culture is proposed. A model of periodic CO2 dosing including dosing time calculation, dosing interval estimation and final chlorophyll yield prediction was established. In experiments, 5% CO2/95% N2 gas was periodically dosed into D. salina culture. Two different gas dosing flow rates were tested. The corresponding dosing time for each flow rate was estimated via the model (10 min·d-1 for 0.7 L·min-1 and 36 min·d-1 for 0.3 L·min-1). Daily pH measurements showed that the pH of these cultures dosed periodically was always kept between 7.5 and 9.5, which highlights that periodic gas supply can maintain a suitable range of pH for microalgal growth without expensive buffers. Notably the culture dosed for set daily intervals was seen to have similar growth to the culture supplied constantly, but with much higher CO2 capture efficiency (11%-18%) compared to continuous dosing (0.25%). It shows great potential for using periodic gas supply to reduce cost, wasted gas and energy use.