Oxygen transfer in a pressurized airlift bioreactor

Author(s)

Campani, Gilson ^[1] ; Arruda Ribeiro, Marcelo Perencin ^[2] ; Luperni Horta, Antonio Carlos ^{[2, 1]} ; Giordano, Roberto Campos ^{[2, 1]} ; Badino, Alberto Colli ^{[2, 1]} ; Zangirolami, Teresa Cristina ^{[2, 1]}

Affiliation

^[1] Fed Univ Sao Carlos PPEQ UFSCar, Chem Engn Grad Program, Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem Engn, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Bioprocess and Biosystems Engineering; v. 38, n. 8, p. 1559-1567, AUG 2015.
• Web of Science Citations: 8

Abstract

Airlift bioreactors (ALBs) offer advantages over conventional systems, such as simplicity of construction, reduced risk of contamination, and efficient gas-liquid dispersion with low power consumption. ALBs are usually operated under atmospheric pressure. However, in bioprocesses with high oxygen demand, such as high cell density cultures, oxygen limitation may occur even when operating with high superficial gas velocity and air enriched with oxygen. One way of overcoming this drawback is to pressurize the reactor. In this configuration, it is important to assess the influence of bioreactor internal pressure on the gas hold-up, volumetric oxygen transfer coefficient (), and volumetric oxygen transfer rate (). Experiments were carried out in a concentric-tube airlift bioreactor with a 5 dm(3) working volume, equipped with a system for automatic monitoring and control of the pressure, temperature, and inlet gas flow rate. The results showed that, in disagreement with previous published results for bubble column and external loop airlift reactors, overpressure did not significantly affect within the studied ranges of pressure (0.1-0.4 MPa) and superficial gas velocity in the riser (0.032-0.065 m s(-1)). Nevertheless, a positive effect on was observed: it increased up to 5.4 times, surpassing by 2.3 times the oxygen transfer in a 4 dm(3) stirred tank reactor operated under standard cultivation conditions. These results contribute to the development of non-conventional reactors, especially pneumatic bioreactors operated using novel strategies for oxygen control. (AU)

• FAPESP's process: 11/16605-3 - Cultivation of rE. coli in airlift bioreactor: development of strategies for optimization of biomass production
• Grantee: Gilson Campani Junior
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 08/05207-4 - Pneumococcal conjugate vaccine: capsular polysaccharide - pneumococcal surface protein A
• Grantee: Martha Massako Tanizaki
• Support Opportunities: Research Projects - Thematic Grants