This paper presents a one-dimensional (1-D) model of the secondary settling tank (SST), and the drive for model development is discussed using steady-state simulation results generated with a 2-D computational fluid dynamics (CFD) model. Concentration profiles measured in a flat-bottom circular (fbSST) that is equipped with suction-lift sludge removal, served for CFD model validation. We investigate the factors that may deteriorate the 1-D simulation performance of clarifier models, which incorporate dispersion both in terms of the effluent sludge concentration and in terms of the sludge blanket height.
View Article and Find Full Text PDFThe CFD (computational fluid dynamics) technique is used to describe the mixing conditions in a pilot-scale FCC (forced-circulation crystallizer) and to study the impact of flow rate and aspect ratio on local flow conditions and RTD (residence-time distribution) in the crystallizer. The analysis adequately predicts the oscillating flow and two-phase (gas-liquid) interaction at the free surface. A comparison has been made between the CFD predictions and models of RTD.
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