Premium
Design of a Tubular Loop Bioreactor for Scale‐up and Scale‐down of Fermentation Processes
Author(s) -
Papagianni Maria,
Mattey Michael,
Kristiansen Bjorn
Publication year - 2003
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp030002y
Subject(s) - bioreactor , scale up , peristaltic pump , fermentation , airlift , continuous stirred tank reactor , natural circulation , scaling , scale (ratio) , loop (graph theory) , process engineering , environmental science , biological system , chemistry , chromatography , chemical engineering , mechanics , mathematics , biology , physics , engineering , thermodynamics , biochemistry , geometry , organic chemistry , classical mechanics , quantum mechanics , combinatorics
Abstract Microorganisms traveling through circulation loops in large‐scale bioreactors experience variations in their environment such as dissolved oxygen concentration and pH gradients. The same changes are not experienced in small bioreactors, and it is suggested that herein lies one of the major reasons for the problems encountered when translating fermentation data from one scale to another. One approach to study this problem is to look at the circulation loop itself. The present work concerns an attempt to simulate the circulation loops inside stirred tank reactors, using a tubular loop reactor specially constructed for the purpose. The reactor carries a number of ports and probes along its length for the determination of concentration gradients within. The broth is circulated around the loop by the use of peristaltic pumps, and the circulation time ( t c , s) is used as a measure of simulated reactor size. The reactor system has been evaluated using the citric acid fermentation by Aspergillus niger as a test process. Acid production and fungal morphology, in terms of the mean convex perimeter of mycelial clumps quantified by image analysis, were used as the parameters of evaluation for the two systems in comparison. From comparative experiments carried out in 10 and 200 L stirred tank bioreactors, it appears that the loop reactor simulates the corresponding stirred tank representing a valuable tool in scaling up and scaling down of fermentation process.