Simulation-based Analysis and Design of Polydisperse Fluidized Bed Reactors

最大限度地减少废水排放到环境中的磷是加拿大和世界各地市政当局日益重要的考虑因素。进入溪流、河流和湖泊的磷排放是这些水体富营养化的主要驱动因素之一，在这些水体中，高水平的生物营养物质的存在会导致植物和藻类的生长增加。这种增加随后导致水体中氧气水平的枯竭，这对鱼类和水生生态系统内的整体生物多样性产生了毁灭性的影响。因此，从废水中去除磷是加拿大研究和开发的一个关键领域**Ostara养分回收公司(Ostara)开发了能够从废水中回收磷的技术，从而使回收的含磷固体(鸟粪石)可以用作缓释肥料。Ostara的核心技术是PEARL®沸腾床反应器，能够从废水处理厂回收高达50%的磷，并(从该过程中)生产出可供分配的富磷肥料产品。这项技术的核心是复杂的多相流态化结晶过程，其中多分散(鸟粪石)固体颗粒分散在多组分的液体(废水)中。**进一步发展Ostara的珍珠反应堆技术需要多相多物理模拟，以便能够预测和分析内部多相流体动力学，同时能够预测和分析发生在固/液界面的结晶过程所产生的传质。这项研究项目涉及对Ostara珍珠反应堆装置的流态化程度和特性的预测，这将使现有设计的优化和下一代磷回收技术的创造成为可能。此外，拟议的研究项目将有助于我们理解多相流体力学，其中分散相是多分散的，即包含不止一种固体颗粒尺寸。

The minimization of phosphorous discharge from wastewater streams into the environment is an increasingly important consideration for municipalities in Canada and throughout the world. Phosphorous discharge into streams, rivers, and lakes is one of the main drivers of eutrophication of these water bodies, where the presence of high levels of biological nutrients results in increased growth of plants and algae. This increase subsequently results in depletion of oxygen levels in water bodies which has devastating effects on fish and overall**biodiversity within aquatic ecosystems. Removal of phosphorous from wastewater is thus a key area of research and development in Canada** Ostara Nutrient Recovery Inc. (Ostara) has developed technologies which enable the recovery of phosphorous from wastewater streams in a way such that the recovered phosphorous containing solids (struvite) may be used as a slow-release fertilizer. Ostara's core technology is the Pearl® fluidized bed reactor, is able to recover up to 50% of phosphorous from a wastewater treatment plant and which outputs (from the process) phosphorous-rich fertilizer production, in a form ready for distribution. At the heart of this technology is a complex multiphase fluidized crystallization process where polydisperse (struvite) solid particles are dispersed in a multi-component liquid phase (wastewater).** Further advancement of the Ostara's Pearl reactor technology requires multiphase multiphysics simulations to enable prediction and analysis of the internal multiphase hydrodynamics and, simultaneously, the mass transfer resulting from the crystallization process occurring at the solid/liquid interface. This research project involves the prediction of the the degree and character of fluidization of Ostara's Pearl reactor units which will enable both the optimization of existing designs and the creation of next-generation of phosphorous recovery technology. Furthermore, the proposed research project would make contributions to our understanding of multiphase hydrodynamics in which the dispersed phase is polydisperse, i.e. containing more than one solid particle size.******