Understanding attrition of irregular particles using a novel DEM simulation approach

使用新颖的 DEM 模拟方法了解不规则颗粒的磨损

基本信息

批准号：
EP/R005877/1
负责人：
Kevin John Hanley
金额：
$ 143.33万
依托单位：
University of Edinburgh
依托单位国家：
英国
项目类别：
Fellowship
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FR005877%2F1
关键词：
Understanding attrition irregular particles using

项目摘要

Irregular particles are ubiquitous, ranging from mineral ores to coffee granules to crystalline active pharmaceutical ingredients. Particle shape has a huge effect on the behaviour of a bulk material. It affects the height and porosity of a static packing of particles, and variability in particle shape can induce segregation in dynamic systems. Particle shapes often change over time due to attrition, i.e., fragmentation or surface abrasion. This has important practical consequences. In the food and pharmaceutical sectors, fine particles generated by undesired attrition impair flow which creates problems during subsequent processing. The particulate catalysts used in oil refining for fluid catalytic cracking (FCC) are susceptible to mechanical degradation which has both environmental and cost implications.The discrete element method (DEM) is a widely used simulation tool used to model complex systems of particles. Currently, there is neither a viable method to simulate particle abrasion in DEM nor an open-source DEM code which can simulate irregular particles of any shape in an efficient manner. This severely limits our particle-scale simulation capabilities, preventing industry from fully understanding their particle processes by simulation.This Fellowship will create an openly-available, efficient and flexible method for simulating irregular, abradable particles. This will have a transformative effect by creating an entirely new field of particle simulations. These numerical advances will be implemented in an open-source code, LAMMPS, with the coding support of Edinburgh Parallel Computing Centre. The code will then be used to simulate two applications of significant economic importance. The first is the attrition of FCC catalyst particles. DEM simulations will be used to predict the catalyst replacement frequency in an industrial FCC unit. The mechanisms of catalyst degradation will be explored, including the effects of particle shape and micro-scale mechanical properties. Having a better scientific understanding of these mechanisms will facilitate more reliable predictions of attrition and hence permit catalysts to be designed with increased attrition resistance. The second application is the breakage of pharmaceutical crystals in agitated filter dryers or granulators. In the pharmaceutical industry, needle- and plate-type crystals are often produced which are highly susceptible to attrition. The modelling approach adopted in this work will enable quantitative prediction of crystal attrition during shear processes including agitated drying and mixing. The extent of this attrition will be linked to changes in bulk density, flowability and other key quality attributes. Better predictive capabilities will enable better control of particle size distributions in manufacturing processes, potentially leading to significant economic savings.This research will be undertaken within the Institute for Infrastructure and Environment, School of Engineering at the University of Edinburgh with the support of three project partners: Sandia National Laboratories, BASF (Refining Catalysts) and AstraZeneca. Sandia are the main developers of the LAMMPS code. They will assist with dissemination by including these code developments in the main, open-source LAMMPS distribution. BASF will provide physical test data on the properties and attrition behaviour of FCC catalysts, and host research visits for collaboration at their premises. Similarly, AstraZeneca will provide experimental data and host research visits, and will also make their laboratory facilities available for testing. The involvement of these partners ensures that the research will be informed by the needs of industry and will have a practical, tangible impact.

不规则颗粒无处不在，从矿石到咖啡颗粒再到结晶活性药物成分。颗粒形状对散装材料的行为有巨大影响。它影响颗粒静态堆积的高度和孔隙率，颗粒形状的变化会导致动态系统中的分离。由于磨损（即破碎或表面磨损），颗粒形状通常会随着时间而改变。这具有重要的实际后果。在食品和制药领域，不良磨损产生的细颗粒会损害流动，从而在后续加工过程中产生问题。用于流体催化裂化 (FCC) 炼油的颗粒催化剂容易受到机械降解的影响，这对环境和成本都有影响。离散元法 (DEM) 是一种广泛使用的模拟工具，用于对复杂的颗粒系统进行建模。目前，既没有可行的方法在DEM中模拟颗粒磨损，也没有可以有效模拟任何形状的不规则颗粒的开源DEM代码。这严重限制了我们的颗粒尺度模拟能力，阻碍了工业界通过模拟充分了解其颗粒过程。该奖学金将创建一种公开可用、高效且灵活的方法来模拟不规则、可磨损的颗粒。这将通过创建一个全新的粒子模拟领域来产生变革性的效果。这些数值上的进步将在爱丁堡并行计算中心的编码支持下以开源代码 LAMMPS 的形式实现。然后，该代码将用于模拟两个具有重大经济意义的应用程序。首先是FCC催化剂颗粒的磨损。 DEM 模拟将用于预测工业 FCC 装置中的催化剂更换频率。将探索催化剂降解的机制，包括颗粒形状和微观机械性能的影响。对这些机制有更好的科学理解将有助于更可靠地预测磨损，从而允许设计出具有更高耐磨性的催化剂。第二个应用是在搅拌过滤干燥机或造粒机中破碎药物晶体。在制药工业中，经常生产极易磨损的针状和板状晶体。这项工作中采用的建模方法将能够定量预测剪切过程（包括搅拌干燥和混合）期间的晶体磨损。这种磨损的程度与堆积密度、流动性和其他关键质量属性的变化有关。更好的预测能力将能够更好地控制制造过程中的粒度分布，从而可能带来显着的经济效益。这项研究将在爱丁堡大学工程学院基础设施与环境研究所内进行，并得到三个项目合作伙伴的支持：桑迪亚国家实验室、巴斯夫（炼油催化剂）和阿斯利康。 Sandia 是 LAMMPS 代码的主要开发者。他们将通过将这些代码开发包含在主要的开源 LAMMPS 发行版中来协助传播。巴斯夫将提供有关 FCC 催化剂性能和磨损行为的物理测试数据，并在其工厂举办合作研究访问。同样，阿斯利康将提供实验数据并主持研究访问，还将提供其实验室设施用于测试。这些合作伙伴的参与确保了研究能够满足行业的需求，并产生实际、切实的影响。