Extraction in pump-mixers with presence of solid phase

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High turbulence generation in a pump-mixer (mixer has a suction characteristics: no pumps required) intensifies the extraction process by increasing interfacial area and thus mass transfer (mainly small droplets are produced). The proposal aims to investigate the interaction of hydrodynamics and solids in a three-phase liquid-liquid-solid extraction process inside a pump-mixer.The hydrodynamics in a pump-mixer will be analyzed using statistical and hybrid CFD methods, which have already been successfully proven in single-phase and cavitation flow. A stepwise approach from one to three phases is planned and a validation is possible in already existing lab-scale apparats. However, there exists no systematic analysis in such apparatus geometries, which is also complained by industry. At high turbulences erosion and at low deposits and scaling will occur causing costs and lowering efficiency. A systematic analysis in such three-phase systems starts with Basic Experiments followed by more realistic conditions (with sand) resulting into a combined CFD-population balance simulation.Based on experimental results, empirical models/correlations have to be expanded and modified subsequently to express the dependency of dispersion characteristics (such as coalescence kernels) on various influencing parameters (as the rotational velocity of the impeller, phase concentration, density, etc.) as function of the solids behavior.The output of the project is generic and not fixed to a certain geometry or system. A spin-off to e.g. centrifugal pumps, used as a cheap mixing devise, or to gas-solid-liquid systems is also feasible. As a further feature, a CFD supported design will allow to develop an adapted apparatus design in presence of solids with either erosion or deposition dominated cases.