Application of capacitance electrical tomography for on-line and off-line analysis of flow pattern in horizontal pipeline of pneumatic conveyer

Investigation and control of flow phenomena in the pneumatic conveying of s olids requires a detailed knowledge on the flow regimes and a number of pha se flow properties. Electrical capacitance tomography (ECT) is shown here t o be a robust tool for this purpose, particularly when dense phase plug flo w is to be monitored. The application of ECT to dense phase powder conveyin g in an experimental vacuum system is demonstrated and described, including the visualisation of slug size, shape and velocity. Measured gas and solid flow rates were also analysed in an attempt to ultimately provide a basis for comprehensive on-line analysis. A number of statistical estimators were selected and used in data processing, in order to distinguish between part icular types of dense flow. The results show the potential for use of the m ethod for the on-line control of dense phase pneumatic conveyors. (C)2000 E lsevier Science S.A. All rights reserved.