Process Simulation of Continuous Bioconversions in Aqueous Two-Phase Systems
Progress in biotechnology largely depends on fermentation optimisation and improvement in downstream processing. These improvements get strongly supported if an integration of fermentation and product extraction can be verified in one processing unit. Continuous bioconversions in aqueous two-phase systems show a great potential of combining these two unit operations. General requirements are the capability of cells and substrates to enrich in one of the phases and the tendency of products to diffuse in the opposite phase. This integrated process is most promising for reaction systems, which exhibit kinetics characterised by product inhibition and, in addition, the process facilitates cell recycling and supports an increase in cell concentration. However, the industrial realisation of this technique is still not fully developed mainly due to difficulties in measurement and control, and to a lack of profitable products. In this work the conversion of glucose to ethanol is used as a model study to develop mathematical optimisation criteria and to create a “feasibility window” for the ongoing search for products.
KeywordsSpecific Growth Rate Dilution Rate Product Inhibition Bottom Phase Hydraulic Residence Time
Unable to display preview. Download preview PDF.
- 1.P.-Å. Albertsson, Partition of Cell Particles and Macromolecules, 3rd ed., John Wiley & Sons (1985)Google Scholar
- 2.M.-R. Kula, Liquid-liquid extraction of biopolymers, in: “Comprehensive Biotechnology,” Vol. 2, Pergamon Press (1985)Google Scholar
- 4.B. Mattiasson and M. Larsson, Extractive bioconversion with emphasis on solvent production, Biotech. and Gen. Eng. Reviews 3:137 (1985)Google Scholar
- 5.M. Larsson and B. Mattiasson, Novel process technology for biotechnological solvent production, Chem. and Ind. June (1984)Google Scholar
- 7.A. Moser, Bioprozesstechnik, Springer-Verlag, Berlin (1981)Google Scholar
- 8.N.W.F. Kossen and N.M.G. Oosterhuis, Modelling and scaling-up of bioreactors, in: “Biotechnology,” Vol. 2, Verlang Chemie, (1985)Google Scholar
- 10.B. Hahn-Hägerdal, Fermentation and product formation in aqueous two-phase systems with yeast and bacillus Sp., Lectures given at a Workshop of the WP Microbial Physiology of the EFB, University of Lund (1986)Google Scholar
- 12.C. D. Bazua and C.R. Wilke, Ethanol effects on the kinetics of a continuous fermentation with Sacch. cer., Biotech. Bioeng. Symp. 7:105 (1977)Google Scholar
- 16.F.F. Pironti, Kinetics of alcohol fermentations, Ph.D. Thesis, Cornell UniversityGoogle Scholar