TY - JOUR
T1 - Experimental analysis and model-based optimization of microalgae growth in photo-bioreactors using flue gas
AU - He, Lian
AU - Subramanian, Venkat R.
AU - Tang, Yinjie J.
N1 - Funding Information:
We thank Dr. Himadri Pakrasi for providing microalgae species, Dr. Benjamin Kumfer for helping measure CO 2 concentration in the flue gas, and Qiaoling Liu for updating the on–off control system. We also thank Cheryl Immethun for proofreading the paper. This study was supported by Consortium for Clean Coal Utilization at Washington University and by an NSF Career Grant ( MCB0954016 ).
PY - 2012/6
Y1 - 2012/6
N2 - This study tested the growth of three algal species (Chlorella sp., Synechocystis sp. PCC 6803, and Tetraselmis suecica) using flue gas (generated by natural gas combustion). All the cultures showed poor biomass growth if they were exposed to continuous flue gas. To optimize the flue gas utilization in algal photo-bioreactors, we performed both model simulations and experimental analysis. First, we employed an un-segregated Monod-based model to describe the microalgal growth in response to CO 2 in the photo-bioreactor. Via the dynamic optimization approach (DOA), the model profiled time-dependent CO 2 concentrations (volume fraction ranging from 0.1 to 0.6%) to support maximal biomass growth. Second, we designed an on-off flue gas pulse mode to reduce CO 2 inhibition (a volume fraction up to 15% CO 2) to the algal cells. Based on the reported algal kinetic parameters, our model predicted that gas-on (~10s CO 2 pulse) and gas-off (5-9min) could achieve over 90% of the maximum theoretical algal growth rate predicted by the DOA. Third, we used mass flow controllers to apply on-off flue gas pulses in photo-bioreactors, and the experimental results verified that the flue gas pulses could reduce flue gas inhibition and improve Chlorella growth compared to cultures exposed to atmospheric CO 2.
AB - This study tested the growth of three algal species (Chlorella sp., Synechocystis sp. PCC 6803, and Tetraselmis suecica) using flue gas (generated by natural gas combustion). All the cultures showed poor biomass growth if they were exposed to continuous flue gas. To optimize the flue gas utilization in algal photo-bioreactors, we performed both model simulations and experimental analysis. First, we employed an un-segregated Monod-based model to describe the microalgal growth in response to CO 2 in the photo-bioreactor. Via the dynamic optimization approach (DOA), the model profiled time-dependent CO 2 concentrations (volume fraction ranging from 0.1 to 0.6%) to support maximal biomass growth. Second, we designed an on-off flue gas pulse mode to reduce CO 2 inhibition (a volume fraction up to 15% CO 2) to the algal cells. Based on the reported algal kinetic parameters, our model predicted that gas-on (~10s CO 2 pulse) and gas-off (5-9min) could achieve over 90% of the maximum theoretical algal growth rate predicted by the DOA. Third, we used mass flow controllers to apply on-off flue gas pulses in photo-bioreactors, and the experimental results verified that the flue gas pulses could reduce flue gas inhibition and improve Chlorella growth compared to cultures exposed to atmospheric CO 2.
KW - CO
KW - Chlorella
KW - Dynamic optimization
KW - Inhibition
KW - On-off pulse
KW - Simulink
UR - https://www.scopus.com/pages/publications/84859513927
U2 - 10.1016/j.biombioe.2012.02.025
DO - 10.1016/j.biombioe.2012.02.025
M3 - Article
AN - SCOPUS:84859513927
SN - 0961-9534
VL - 41
SP - 131
EP - 138
JO - Biomass and Bioenergy
JF - Biomass and Bioenergy
ER -