Results of the disintegration of yeast Saccharomyces cerevisiae in the bead mill with a multi disk impeller are presented. The degree of disintegration was specified on the basis of absorbency measurements at the wavelength 260 nm. The process was investigated by two integrated methods. The experimental values of maximum absorbency Am2 appeared to be smaller than theoretical ones Am1, which resulted from searching for the highest values of correlation coefficient between variables t and ln[Am1 / (Am1 – A)]. A significant increase of the process rate constant was observed when the slurry concentration increased in the range from 0.05 to 0.20 g d.m./cm3. This phenomenon was explained by an additional mechanism of cell destruction, which was induced by fragments of ground walls. The rate constant changed during the process due to a change of inner process conditions, and not directly as a result of a changing number of microbial cells. Modeling of the process in which the first-order differential equation is used to describe the kinetics is correct, with the process rate constant being a function of parameters that describe inner conditions changing during the process.
Part of the book: Mass Transfer