Modeling of local dynamic behavior of phenol degradation in an internal loop airlift bioreactor by yeast Candida tropicalis

• Published in: Biotechnology and bioengineering Vol. 97; no. 2; pp. 251 - 264
• Main Authors: Feng, Wei, Wen, Jianping, Liu, Cuiyun, Yuan, Qing, Jia, Xiaoqiang, Sun, Yan
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.06.2007; Wiley; Wiley Subscription Services, Inc
• Subjects: Air Movements; airlift reactor; Biochemistry; Biological and medical sciences; Bioreactors; Biotechnology; Candida tropicalis; Candida tropicalis - physiology; Cell growth; CFD; dynamic behavior; Fluid dynamics; Fundamental and applied biological sciences. Psychology; Gases; Hydrography; modeling; Models, Biological; Organic chemistry; Phenol - metabolism; phenol degradation; CFD; Airlift reactor; Yeast; dynamic behavior; Modeling; Fungi; Degradation; Bioreactor; Phenol; Dynamics; Phenols; Candida tropicalis; Fungi Imperfecti; Thallophyta; phenol degradation
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.21215

A coupled computational fluid dynamic (CFD) model, combining hydrodynamics with biochemical reactions, was developed to simulate the local transient flow patterns and the dynamic behaviors of cell growth and phenol biodegradation by yeast Candida tropicalis in an internal loop airlift reactor (ILALR). To validate this proposed model effectively, the simulated local hydrodynamic characteristics of the gas‐mineral salt medium solution (gas‐liquid) two‐phase system, at a phenol concentration of 1,200 mg L−1 and no presence of cells, was experimentally investigated in the ILALR using laser Doppler anemometer (LDA) measurements and conductivity probe. Furthermore, the validation of the simulated phenol biodegradation behavior by C. tropicalis at different initial concentrations of phenol and cell was also carried out in the ILALR. The time‐averaged and transient results of the model simulations illustrated a satisfactory agreement with the experimental data. Finally, the local instantaneous flow and phenol biodegradation features, including gas holdup, gas velocity, liquid velocity, cell concentration, and phenol concentration inside the ILALR were successfully predicted by the proposed model. Biotechnol. Bioeng. 2007;97: 251–264. © 2006 Wiley Periodicals, Inc.