Analysis of partial suspension in stirred mixing cells using both MRI and ERT

Magnetic resonance imaging (MRI) and electrical resistance tomography (ERT) are collectively used to examine partial suspension of various glass and nylon particles in the same stirred baffled mixing cell of inner diameter 50 mm. Virtually complete suspension is observed to occur at critical agitation rates considerably lower than expected. Radial and axial particle concentration profiles, as measured using MRI and ERT, compare reasonably well. The higher resolution of MRI is able to detect concentration variations adjacent to the vessel wall whilst fillet formation of unsuspended solids is imaged at the base of the cell. To the best of our knowledge, this study represents the first direct comparison of MRI against ERT.