Structural kinetic modeling network analysis

Figure 25. Structural Kinetic Modeling seeks to keep the advantages of stoichiometric analysis, while incorporating dynamic properties into the description of the system. Specifically, SKM aims to give a quantitative account of the possible dynamics of a metabolic network.

The chemical reactor has a determinant role on both the material balance and the structure of the whole flowsheet. It is important to stress that the downstream levels in the Hierarchical Approach, as the separation system and heat integration, depend entirely on the composition of the reactor exit stream. However, a comprehensive kinetic model of the reaction network is hardly available at an early conceptual stage. To overcome this shortcoming, in a first attempt we may neglect the interaction between the reactor and the rest of the process, and use an analysis based on stoichiometry. A reliable quantitative relationship between the input and the output molar flow rates of components would be sufficient. This information is usually available from laboratory studies on chemistry. Kinetics requires much more effort, which may be justified only after proving that the process is feasible. Note that the detailed description of stoichiometry, taking into account the formation of sub-products and impurities is not a trivial task. The effort is necessary, because otherwise the separation system will be largely underestimated. 

Due to lack of kinetic parameters, structural metabolic network modeling has been widely applied for analyzing cellular metabolism under steady-state. Depending on what assumptions are made and whether experimental data are required, different techniques have been developed to analyze the invariant of metabohc networks such as metabolic flux analysis (MFA), flux balance analysis (FBA), and metabolic pathway analysis (MPA) including elementary mode and extreme pathway analyses (Lewis et al. 2012 Stephanopoulos et al. 1998 Trinh et al. 2(X)9). 

The deviations from typical behavior of oligomers are usually explained at the qualitative level within the kinetic theory of liquids by Ya.l. Frenkel [80]. Here, the models of the hooking network [177] or aggregative structure [128,141,230] are used. The application of the scaling hypothesis [32] for the analysis of oligomer solution dynamic properties gave a form of quantitative dependences to the hooking network idea [237]. 

---