In Part I of this study a theoretical model was recommended describing the hydraulic characteristics, being Sauter drop diameter, hold-up, operating regimes, and operational window, of caprolactam extraction in a pulsed disc and doughnut column. In order to confirm the theoretical model pilot plant experiments for the caprolactam forward and back-extraction were performed to determine the hydraulic characteristics as a function of the operating conditions. The experimental conditions covered the industrial operating range. All hydraulic experiments were performed at equilibrium conditions in order to avoid the influence of mass transfer.In the determination of the operational window flooding because of too low pulsation was qualitatively observed, while it was found that at high pulsation phase inversion was limiting for the back-extraction process and flooding for the forward extraction process. Application of the in Part I recommended theoretical model for the description of the obtained hydraulic data resulted in an accurate description after fitting the drop diameter, hold-up, and phase inversion data.

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Caprolactam is obtained by extraction using organic solvents like benzene, toluene, or chlorinated hydrocarbons. As an alternative solvent, the mixed solvent heptane-heptanol (40 mass %) was selected in previous studies based on a relatively high distribution ratio of caprolactam, a low mutual solvent solubility, beneficial physical properties, and a low distribution ratio of impurities. Now, the hydraulic and mass transfer characteristics of the extraction of caprolactam in a pulsed disc and doughnut column (PDDC) were investigated using the benign solvent. The results were compared to those for toluene.The PDDC showed qualitatively comparable operational characteristics for both solvents. In the hydraulic experiments the mixed solvent showed smaller drop diameters and hold-ups, required lower pulsation intensities for regime transitions, but the operational windows are slightly smaller. For both solvents, mass transfer resulted in increasing drop diameters and pulsation intensities required for regime transition. In the forward extraction the mixed solvent was superior, where HETS/m ¼ 0.26 to 0.37, compared to 0.42 to 0.67 for toluene, while less theoretical stages are required as well. For the back-extraction HETS/m ¼ 0.33 to 0.40 for the mixed solvent compared to 0.30 to 0.37, but toluene requires the lower amount of theoretical stages.The hydraulic characteristics at equilibrium and concentration profiles in both the forward and back-extraction were described accurately using the developed models.

I will present a model-free Data-Driven computing framework for multiscale analysis of inelastic materials. The aim of the framework is to enable predictions of structural response directly from material data, without the intermediate step of modeling the data by means of constitutive relations. A distinguishing aspect of the formulation is that it is internal-variable free, i.e., it does not require the identification of actual or ad hoc (learned) internal variables. Instead, the inelastic macroscopic response and its evolution are characterized by defining a dissipation connection in macroscopic phase space. We show how the phase field can be sampled, and the dissipation connection identified, directly from micromechanical calculations on representative-volume elements (RVEs). The data is reusable over a broad range of boundary-value problems and loading conditions involving the same material. Solutions to specific boundary-value problems are obtained by minimizing a distance from the material sample to the set of equilibrium and compatible states and, in a time-discrete setting, by simultaneously minimizing the incremental dissipation. We demonstrate the framework by means of an application concerned with the prediction of the behavior of sand, a prototypical complex historydependent material.