Bioprocess intensification through bioreactor engineering

An overview of methods for intensification of bioprocesses is presented. Schemes focused on bioreactor and bioreaction engineering are the primary means of commercially-relevant process intensification. Examples are used to illustrate some of the available options : improved oxygen transfer by use of static mixers and other means ; enhancement of heat transfer ; slurry bioreactors for improved solid-liquid mass transfer and efficient suspension of the biocatalyst ; modification of fermentation conditions to amplify productivity ; high density cell culture bioreactors ; design modifications for low-shear bulk mixing of shear-sensitive, viscous broths ; use of additives as shear protectants ; and high-efficiency airlift bioreactors. Methods that are commonly used for intensification of chemical processes are generally too severe for use with biocatalysts. Of the available strategies for bioprocess intensification, some, such as enhancement of oxygen transfer, have broader applicability than others. For the foreseeable future, empirical strategies are expected to remain the primary means of bioprocess intensification. Intensification goals are most effectively achieved through multidisciplinary approaches implemented at the earliest stages of process research.