|REDDY, S - Kle University|
|CHANDRIKA, K - Kle University|
|PAVANI, P - Kle University|
|BALA CHAITNANYA, T - Kle University|
|SANDEEP, V - Kle University|
|SARADHI, V - Kle University|
|RAO, P - Kle University|
|SURAJ, S - University Of Georgia|
Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2014
Publication Date: 7/24/2014
Citation: Reddy, S., Chandrika, K., Pavani, P.L., Bala Chaitnanya, T.V., Sandeep, V., Saradhi, V., Rao, P., Suraj, S., Kandala, C. 2014. A growth inhibitory model with SOx influenced effective growth rate for estimation of algal biomass concentration under flue gas atmosphere. Bioresource Technology. 152:283-291.
Interpretive Summary: Notwithstanding the fact that Microalgae and its products have been used as food, feed, and as a nutritional supplement for several decades, the recent identification of a few micro-algal species capable of accumulating high lipid content in biomass has opened avenues to explore the algae as a potential bio-fuel feedstock. Micro-algal cultivation technologies in closed photo-bioreactor systems and the design of flue treatment methodologies with CO2 as a major carbon source, has resulted in the utilization of stack gas resources in the generation of algal biomass for fuel applications. During this process, the conversion technologies were often either compromised with the yield of the biomass or with the specific yield of the product. Therefore, the predictability of biomass concentration under flue gas will be the key factor for understanding the inhibitory parameters which will enable the design of better strategies for optimization of the process. This work highlights algal growth modeling in the presence of flue gas for prediction of biomass concentration. The growth profile of the algae under flue gas was successfully modeled in this work. This work is novel and useful for predicting growth in medium to large scale algal photo-bioreactors treated with flue gas. The model could find applications in CO2 sequestration, and in the generation of algal biomass, useful for bio-fuel production.
Technical Abstract: A theoretical model for the prediction of biomass concentration under real flue gas emission has been developed. The model considers the CO2 mass transfer rate, the critical SOx concentration and its role on pH based inter-conversion of bicarbonate in model building. The calibration and subsequent validation of the growth profile of N. limnetica at 2% and 10% (v/v) CO2 showed that the predicted values were consistent with the measured values; r2 being 0.96 and 0.98 respectively; p < 0.001 in both cases. The sensitivity analysis also justifies the constants being used in the model. Validation at various flow rates (1.5-4.5 L min-1) showed that the model applicability was defined over ± 30% of the calibrated flow rate (3.0 L min-1).The model can be a useful tool for predicting algal growth in photo-bioreactors treated with flue gas in the generation of biomass feed stock for fuel applications.