IDENTIFICATION OF FERMENTATIONS BY POLYNOMIAL METHODS

Abstract

The measure of the state variables of a fermentation (biomass and substrate concentration) is always liable to error. It is possible to reconstitute well enough the rates of their variations during a transient state, by a polynomial smoothing. By calculation of the derivative polynomial, the values of the growth rate HM and the global conversion rate R. at each moment can be deduced. The fermentation parameters are then identified through 2 linear smoothings. The method is tested with data obtained by simulation and given purposely noisy (known parameters). It is applied in order to determine the growth parameters of a continuous fermentation. The advantage of this direct method upon the usual sequential techniques is its rapidity and its small occupation of the central memory of the computer. It can be applied to continuous or discontinuous fermentation.