Use of CFD-DEM Coupling to Determine the Settling Hindered Velocities for Highly Concentrated Mining Slurries

高浓度矿浆的混合是采矿工业中的一项关键操作。当为这些悬浮液设计固液混合器时，必须考虑到阻碍沉降的速度。然而，由于这些系统固有的复杂性，没有特定的数据提供这些固体颗粒在阻碍沉降环境中的实际沉降速率。目前，Hayward Gordon采用单颗粒沉降速度代替阻碍沉降速度来设计矿浆混合系统。这种不准确的方法会导致船舶尺寸过大，叶轮类型、尺寸和转速的选择不当，效率低，操作困难。因此，Hayward Gordon有兴趣更好地了解阻碍环境中的颗粒沉降过程，以改进和优化其混合设计和制造。因此，本研究的主要目标是通过计算流体力学（CFD）和离散元法（DEM）的耦合方法，获得高浓度矿体中固体浓度、固体密度和颗粒大小对阻碍沉降速度的影响。在CFD-DEM耦合中，正确选择模型至关重要。这项工作对加拿大的采矿业具有重要意义。研究结果将有助于设计高效的高浓度浆料悬浮混合系统。加拿大采矿业和采矿设备制造商可以在计算机上实施CFD-DEM方法来评估许多场景，而无需额外的构建和测试原型模型的成本。这导致了设备设计的改进，更可靠的过程监控，更有效地利用电力，降低了维护和运营成本，最终增加了资本成本节约。因此，拟议的研究将有助于增加加拿大采矿业的经济活动，并将影响我们的社会，生活质量和环境。

Mixing of highly concentrated slurries is a critical operation in mining industry. The hindered settling velocitymust be considered when a solid-liquid mixer is designed for these suspensions. However, due to the inherentcomplexity of these systems, there is no specific data that provides the actual settling rate of these solidparticles in a hindered settling environment.Currently, Hayward Gordon designs mixing systems for mining slurries by using the settling velocity of asingle particle instead of the hindered settling velocity. This inaccurate approach can lead to oversizeddimensioning of the vessel, inappropriate selection of impeller type, size and rotational speed, low energyefficiency and operation difficulties. Therefore, Hayward Gordon is interested in obtaining better insights intothe particle settling process in a hindered environment to refine and optimize their mixing design andmanufacturing. Thus, the main objective of the proposed research project is to obtain the hindered settlingvelocity in highly concentrated mining slurries as a function of the solid concentration, solid density andparticle size through the coupled computational fluid dynamics (CFD) and discrete element method (DEM).The selection of the correct models is crucial in CFD-DEM coupling.This work is of great importance to the mining industry of Canada. The research results will lead to the designof efficient mixing systems for the suspension of highly concentrated slurries. The Canadian mining industryand mining equipment manufacturers can implement the CFD-DEM approach to assess many scenarios on acomputer without the additional costs of constructing and testing prototype models. This leads to an improvedequipment design, a more reliable process monitoring, a more efficient use of power, a decreased maintenanceand operational cost and finally an increased capital cost saving. Thus, the proposed research will contribute tothe increased economic activity of the Canadian mining industry, and will impact our society, quality of lifeand environment.