Faculty of Engineering, Western University, London, Ontario, Canada.
Drug Dev Ind Pharm. 2013 Feb;39(2):331-41. doi: 10.3109/03639045.2012.681055. Epub 2012 May 8.
Product quality in high-shear granulation is easily compromised by minor changes in raw material properties or process conditions. It is desired to develop a process analytical technology (PAT) that can monitor the process in real-time and provide feedback for quality control. In this work, the application of audible acoustic emissions (AAEs) as a PAT tool was investigated. A condenser microphone was placed at the top of the air exhaust on a PMA-10 high-shear granulator to collect AAEs for a design of experiment (DOE) varying impeller speed, total binder volume and spray rate. The results showed the 10 Hz total power spectral densities (TPSDs) between 20 and 250 Hz were significantly affected by the changes in process conditions. Impeller speed and spray rate were shown to have statistically significant effects on granulation wetting, and impeller speed and total binder volume were significant in terms of process end-point. The DOE results were confirmed by a multivariate PLS model of the TPSDs. The scores plot showed separation based on impeller speed in the first component and spray rate in the second component. The findings support the use of AAEs to monitor changes in process conditions in real-time and achieve consistent product quality.
在高剪切制粒过程中，产品质量很容易受到原材料性质或工艺条件的微小变化的影响。人们希望开发一种过程分析技术（PAT），可以实时监测工艺过程并提供质量控制反馈。在这项工作中，研究了可听声发射（AAE）作为 PAT 工具的应用。在 PMA-10 高剪切制粒机的排气口顶部放置一个冷凝器麦克风，以收集用于实验设计（DoE）的声发射，该设计改变了叶轮速度、总粘结剂体积和喷雾速率。结果表明，20 至 250 Hz 之间的 10 Hz 总功率谱密度（TPSD）受到工艺条件变化的显著影响。结果表明，叶轮速度和喷雾速率对造粒润湿有统计学上的显著影响，而叶轮速度和总粘结剂体积在工艺终点方面有显著影响。DoE 结果得到了 TPSD 的多元偏最小二乘模型的证实。得分图显示，第一个组件基于叶轮速度的分离和第二个组件基于喷雾速率的分离。这些发现支持使用 AAE 实时监测工艺条件的变化，并实现一致的产品质量。
