Disruption of microorganisms due to agitation in slurries of fine particles

Master Thesis


Permanent link to this Item
Journal Title
Link to Journal
Journal ISSN
Volume Title

University of Cape Town

This dissertation presents the results of an investigation into the disruption of microorganisms when agitated in slurries of fine particles in a stirred tank. The most widely used industrial process involving agitation of microorganisms in slurries of particles in stirred tanks is the biooxidation process. Mixed cultures of thiobacilli are used in stirred tank reactors for the biooxidation of sulphide minerals. In addition to operating conditions, the efficiency of biotechnological processes is dependent on the growth and metabolism of the microorganisms. The microorganisms are sensitive to the hydrodynamic conditions generated in the processes. In response to adverse hydrodynamic conditions there may be changes in the growth rate of the microorganisms, the nutrient uptake rate, the product formation rate and morphology of the microorganisms. Under extreme conditions cell damage and disruption may ensue. The presence of particulates in bioprocesses, in the form of solid substrates or support systems for attached growth, further complicate the hydrodynamic conditions. The knowledge of the effect of particulates on microorganisms is an important priority.

Bibliography: pages 149-155.