Extraction in pump-mixers with presence of solid phase

泵-混合器中产生的高湍流（混合器具有吸入特性：不需要泵）通过增加界面面积从而加强了萃取过程，从而传递了质量（主要是产生小液滴）。该提案旨在研究泵-混合器内三相液-液-固萃取过程中流体力学与固体的相互作用。本文将采用统计和混合CFD方法对泵-混合器的流体力学进行分析，这些方法已经在单相和空化流动中得到了成功的验证。计划采用从一到三个阶段的逐步方法，并可能在现有的实验室规模的设备上进行验证。然而，对这类仪器的几何形状没有系统的分析，这也引起了工业界的不满。在高湍流下，会发生侵蚀和低沉积结垢，造成成本和效率的降低。对这种三相系统的系统分析从基本实验开始，然后是更现实的条件（含砂），从而形成cfd -种群平衡模拟。基于实验结果，经验模型/相关性必须扩展和随后修改，以表达分散特性（如聚结核）对各种影响参数（如叶轮的转速、相浓度、密度等）作为固体行为函数的依赖关系。项目的输出是通用的，而不是固定到某个几何或系统。作为廉价混合装置的离心泵或气固液系统的衍生产品也是可行的。作为进一步的特点，CFD支持的设计将允许开发适用于固体侵蚀或沉积为主情况下的设备设计。

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.