DEFINING THE DEGREE OF BLENDING OF MICROORGANISMS WITH VARIOUS TIME OF STAYING IN FLOW-LINE BIOREACTORS

Abstract

The possibility of assessing the character of hydrodynamics of two-phase flow in continuously
operated bioreactors is considered, taking into account the presence of microturbulences or lamellar
convective mixing resulting in disturbing sequential movement of microorganisms in the system
(device, unit). It is suggested to perform the mentioned assessment by calculating the shares of microorganisms which differ among themselves by the time of staying in any given volume of the device.
It is known for fact that in case of coexistence in a unit volume of the production substrate of
microorganisms of various age as correlated to their time of stay in a reactor, biochemical process of
the targeted mass exchange runs inefficiently. As metabolic processes are very fast in microorganisms,
changes in their age-related functional characteristics may be associated with the time of stay
of the cells in the system. In order to make key decisions while designing new devices or upgrading
the existing ones with the task of realizing the models of flow approximating to piston flow, one
needs a method of calculating the share of the coexisting microorganisms with various time of stay
in the volume of the bioagents’ flow of interest. The obtained calculated data are important for the
functional-and-structural simulation of a twp-phase flow of agents, among which the living cells of
microorganisms are determinant for biotechnological processes. However, there a solution to assessing
the system’s condition has not of yet been found. This work suggests a probabilitytheoretical
approach to development of a mathematical model helping calculate the share of the coexisting
microorganisms with various time of stay in an arbitrarily given volume of the device by
means of setting initial and boundary conditions. The method is based on assessing the density of
function of distribution according to the time of stay of the microorganisms’ cells in devices. Thus,
the obtained results allow to assess the condition of hydrodynamics of the flow of the system “production substrate - microorganisms”, and based on that to predict the efficiency of biochemical processes realized in flow-line devices.