Application of electrical capacitance tomography in pharmaceutical fluidised beds – A review. (15th February 2021)

• Record Type: Journal Article
• Authors: Wang, Haigang; Yang, Wuqiang
• Is Part Of: Chemical engineering science. Volume 231(2021)
• Publication Date: 2021-02-15
• Subjects: Electrical capacitance tomography -- Pharmaceutical fluidised bed -- Granulation -- Drying -- Coating; 3D three-dimensional -- ANN artificial neural networks -- CFB circulating fluidised bed -- CFD computational fluid dynamics -- CPFD computational particle fluid dynamics -- CQA critical quality attribute -- DAS data acquisition system -- DEM discrete element method -- DWT discrete wavelet transform -- FDA Food and Drug Administration -- FFT fast flourier transform -- ECT electrical capacitance tomography -- ECVT electrical capacitance volume tomography -- EMMS energy-minimisation multi-scale -- ERT electrical resistance tomography -- LBP linear back project -- LARS least angle regression -- LOW loss-of-weight -- MRI magnetic resonance imaging -- MWT microwave tomography -- NIR near infra-red -- OCT optical coherence tomography -- PAT process analytical technology -- PEPT positron emission particle tracking -- PBM population balance model -- PIV Particle Image Velocimetry -- SNR signal-to-noise ratio -- TFM two fluid model -- TL time level -- TV-IT Total-Variation-iterative thresholding; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2020.116236
• Languages: English
• ISSNs: 0009-2509

Abstract

Abstract: Fluidised beds are commonly used in the pharmaceutical industry for granulation, drying and coating of powder or pellets. The product quality strongly depends on the operation of the fluidisation processes. As a pharmaceutical fluidised bed is a typical multi-scale gas-solids flow system, it is important to investigate the flow dynamics by advanced measurement tools for understanding, optimisation and control of the fluidisation processes. Electrical capacitance tomography (ECT) has been used for this purpose in the past two decades. This paper reviews the application of ECT in pharmaceutical fluidised beds. First, the principle of ECT is introduced, followed by typical applications related to pharmaceutical fluidised beds being reviewed, including the characteristics of flow dynamics in granulation, drying and coating processes. Second, diagnosis of process fault and control based on ECT are discussed. Third, ECT results are compared and validated with available data from other sensing modalities, e.g. pressure and optical probes. In the end of the paper, conclusions and the future application of ECT in pharmaceutical fluidised beds as well as key issues for application of ECT in the pharmaceutical industry are discussed, including re-engineering of ECT sensor design and further improvement in image reconstruction.