Investigation of Hydrodynamic Parameters in an Airlift Photobioreactor on CO2 Biofixation by Spirulina sp.

Sustainability

Peyman Malekshahi¹  Zahra Zarei¹  Mohammad Hossein Morowvat²  Antoine P. Trzcinski³ 

[1] Department of Chemical Engineering, University of Sistan & Baluchestan, Zahedan P.O. Box 98167-45845, Iran;Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz P.O. Box 71468-64685, Iran;School of Civil Engineering and Surveying, University of Southern Queensland, West Street, Toowoomba, QLD 4350, Australia;

关键词: airlift photobioreactor;    carbon sequestration;    CO₂ biofixation;    gas holdup;    liquid circulation velocity;    Spirulina sp.;   

DOI  :  10.3390/su14127503

来源: DOAJ

【 摘 要 】

The rise of CO₂ concentration on Earth is a major environmental problem that causes global warming. To solve this issue, carbon capture and sequestration technologies are becoming more and more popular. Among them, cyanobacteria can efficiently sequestrate CO₂, which is an eco-friendly and cost-effective way of reducing carbon dioxide, and algal biomass can be harvested as valuable products. In this study, the hydrodynamic parameters of an airlift photobioreactor such as gas holdup, mean bubble diameter and liquid circulation velocity were measured to investigate CO₂ biofixation by Spirulina sp. The total gas holdup was found to increase linearly with the increase in the gas velocity from 0.185 to 1.936 cm/s. The mean bubble velocities in distilled water only and in the cyanobacterial culture on the first and sixth days of cultivation were 109.97, 87.98, and 65.89 cm/s, respectively. It was found that shear stress at gas velocities greater than 0.857 cm/s led to cyanobacterial death. After 7 days of batch culture, the maximum dry cell weight reached 1.62 g/L at the gas velocity of 0.524 cm/s, whereas the highest carbon dioxide removal efficiency by Spirulina sp. was 55.48% at a gas velocity of 0.185 cm/s, demonstrating that hydrodynamic parameters applied in this study were suitable to grow Spirulina sp. in the airlift photobioreactor and remove CO₂.

【 授权许可】

Unknown