Extraction in pump-mixers with presence of solid phase

泵-混合器(混合器具有吸力特性：不需要泵)中产生的高湍流通过增加界面面积来强化萃取过程，从而使传质(主要是产生小液滴)。该方案旨在研究泵-混合器内液-液-固三相萃取过程中流体力学和固体的相互作用，将使用统计和混合CFD方法对泵-混合器内的流体动力学进行分析，这些方法已经在单相流和空化流动中得到了成功的验证。计划从一个阶段到三个阶段的逐步方法，并有可能在现有的实验室规模的仪器中进行验证。然而，这种仪器的几何形状没有系统的分析，这也是工业界所抱怨的。在高湍流度时会发生侵蚀，而在低湍流度时会发生淤积和结垢，从而导致成本和效率降低。对这类三相系统的系统分析从基本实验开始，然后是更实际的条件(有沙)，从而得到CFD-人口平衡联合模拟。根据实验结果，经验模型/关联式必须随后扩展和修改，以表达分散特性(如聚结核)对各种影响参数(如叶轮转速、相浓度、密度等)的依赖关系。作为实体行为的函数。项目的输出是通用的，并且不固定到特定的几何图形或系统。衍生产品也是可行的，例如用作廉价混合装置的离心泵，或气-固-液系统。作为进一步的特点，CFD支持的设计将允许在固体存在的情况下开发适合的设备设计，无论是侵蚀还是沉积为主的情况。

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.