Computation of the flow and reactive mixing in dual-Rushton ethoxylation reactor

Particle Image Velocimetry Experiments and Large Eddy Simulations of Merging Flow Characteristics in Dual Rushton Turbine Stirred Tanks

“…Figures 7 and 8 compare the simulated axial profiles of phaseaveraged radial velocity and TKE, respectively, with the corresponding LDV and PIV data at different radial positions. The LDV data were taken from Rutherford et al, 13 and the SG (sliding grid) modeling results with the standard k−ε model were taken from Micale et al 18 Because the results obtained by the realizable k−ε model in the present work do not provide better estimates than the SG data, and similar CFD results were also obtained by Chiu et al 22 using the k−ε model with the sliding grid impeller modeling technique, only the SG data of Micale et al 18 are given here for conciseness.…”

“…However, they also pointed out that the experimental velocity and TKE results were read from the published vectors and contours of Rutherford et al, respectively, so there might be errors involved in reading the data. Brucato et al assessed the impeller modeling applicability of IO procedure using the dual Rushton turbine problems and the experimental results of Rutherford et al Deshpande and Ranade verified the computational snapshot approach using the LDV data of Rutherford et al and the simulated results of Micale et al The dual Rushton turbine problem under merging flow pattern was used by Chiu et al , to validate their CFD modeling method before they conducted the flow and reactive mixing simulation of industrial ethoxylation reactors. Montante and Magelli investigated the homogenization process in a multiple Rushton turbines stirred vessel using a Reynolds averaged Navier–Stokes (RANS) based CFD method and found that the turbulent Schmidt number has great influence on the simulated mixing characteristics, and a value of 0.10 is recommended to obtain accurate predicted results.…”

Propoxylation of fatty amines: Switching from batch to flow

“…Usually, a high circulation of the crude through a heat exchanger is necessary in those cases to avoid thermal runaway due to the exothermic reaction enthalpy of −120 kJ/mol EO . The advantages of those newer reactor types are the increased mass and heat transfer while allowing product treatments after each batch according to di Serio et al A considerable amount of detailed models and intensive optimizations have been performed on those processes . Optimal process conditions were reported to be 180°C, the pressure not exceeding 5 bars, working entirely oxygen free and without the use of a catalyst (for fatty amines).…”