Comparison of the hydrodynamics and mass transfer characteristics in internal-loop airlift bioreactors utilizing either a novel membrane-tube sparger or perforated plate sparger.
Two gas spargers, a novel membrane-tube sparger and a perforated plate sparger, were compared in terms of hydrodynamics and mass transfer (or oxygen transfer) performance in an internal-loop airlift bioreactor. The overall gas holdup ε T, downcomer liquid velocity V d, and volumetric mass transfer coefficient K L a were examined depending on superficial gas velocity U G increased in Newtonian and non-Newtonian fluids for the both spargers. Compared with the perforated plate sparger, the bioreactor with the membrane-tube sparger increased the values of ε T by 4.9-48.8% in air-water system when the U G was from 0.004 to 0.04 m/s, and by 65.1-512.6% in air-CMC solution system. The V d value for the membrane-tube sparger was improved by 40.0-86.3%. The value of K L a was increased by 52.8-84.4% in air-water system, and by 63.3-836.3% in air-CMC solution system. Empirical correlations of ε T, V d, and K L a were proposed, and well corresponding with the experimental data with the deviation of 10%.
College of Bioengineering and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, Jiangsu, China, weice@njtech.edu.cn.
Ce
C
Wei
Bing
B
Wu
Ganlu
G
Li
Kequan
K
Chen
Min
M
Jiang
Pingkai
P
Ouyang
D000388:Air; D019149:Bioreactors; D002266:Carboxymethylcellulose Sodium; D004867:Equipment Design; D005740:Gases; D057446:Hydrodynamics; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D010100:Oxygen; D011312:Pressure
D005740:Gases; D008567:Membranes, Artificial; D002266:Carboxymethylcellulose Sodium; D010100:Oxygen