Steady States of a Fermentation Process for Lactic Acid Production at a Given Concentration of the Main Substrate
- PDF / 763,931 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 100 Downloads / 176 Views
dy States of a Fermentation Process for Lactic Acid Production at a Given Concentration of the Main Substrate E. L. Gordeevaa, L. V. Ravicheva, and Yu. L. Gordeevab, * aMendeleev
University of Chemical Technology of Russia, Moscow, 125047 Russia Skryabin Moscow State Academy of Veterinary Medicine and Biotechnology, Moscow, 109472 Russia *e-mail: [email protected]
b
Received January 13, 2020; revised January 21, 2020; accepted February 7, 2020
Abstract—A computational scheme has been presented that generalizes theoretical representations of a technology for the continuous fermentation of lactic acid at a given concentration of the main substrate in the stream that enters a fermenter. The sequence of constructing the computational scheme includes a preliminary analysis and a principal analysis. In the preliminary analysis, relationships have been derived that form the region of estimating the boundary characteristics that correspond to a given productivity of the process. The coordinates of the point of the maximum productivity Sopt , D opt have been found. The coordinates of singular points have also been determined: [S1 ( D1 ) , D1 ] for singular point 1, [S2 ( D2 ) , D2 ] for singular point 2, [S3 ( D3 ) , D3 ] for singular point 3, and [S4 ( D4 ) , D4 ] for singular point 4. For the point of the maximum productivity and singular points, relationships have been presented for calculating the initial concentrations of the main substrate S0 and the corresponding initial concentrations of the component that produces the substrate during fermentation M0. The values of coordinates have been constraints in constructing relationships for the principal analysis that determine sets for selecting the values of M0 and D at a given value of S0. The scheme of the construction of sets consists of three sections, namely, I, II, and III. The boundaries of these sections are determined by relationships (21), (22), and (23), respectively. The sequence of the construction of sets for each of the sections has been presented, and it has been shown that there is one set (Set1) for section I, there are two sets (Set1* and Set2*) for section II, and there are three sets (Set1**, Set2**, and Set3**) for section III. Tables have been given for calculating the elements of sets at a given value of S0. The theoretical relationships that have been derived are used for numerical calculation to estimate the characteristics of the multiplicity of steady states for each of the sets. It is shown that the range of the assignment of S0 is the widest for section I, whereas the range of values for the dilution rate D is the greatest for section III. Numerical estimates in a comparative variant for sets in sections II and III have shown that the final concentrations of components under the same initial conditions differ in the values of M0, M, and S. This makes it possible to obtain comparative estimates for the further processing of produced components (the recovery of lactic acid, the recycling and use of unconverted components, the recov
Data Loading...
