Using Electrical Capacitance Tomography to Monitor Gas Voids in a Packed Bed of Solids

Robert B White

Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Minerals, Bayview Avenue, Clayton, 3168, Victoria, AUSTRALIA

ABSTRACT

Electrical Capacitance Tomography is being widely used to investigate multi-phase systems, in particular in gas-solid systems such as fluidised beds. Commercial systems are available that can provide the researcher with reconstructed tomograms, and this paper introduces a technique to carry out some quantitative analysis of a sequence of reconstructed tomograms. The performance characteristics of an ECT system attached to a 200 mm ID test section is investigated using hollow glass spheres of 40 mm, 65 mm, 85 mm and 100 mm in diameter. The analysis technique discussed in this paper has been used to identify the spheres using a contour plot showing solids fraction, x, contours at x = 0.2, x = 0.5 and x = 0.8 and has also been used to estimate the diameter of the identified spheres. In this way the advantages of the analysis technique and the performance characteristics of the tomography system are presented and compared with others in the literature.

Keywords ECT, calibration, analysis, performance