149f Tomographic Imaging during Semi-Batch Reactive Precipitation of Barium Sulphate In a Stirred Vessel

Thomas L. Rodgers1, David Stephenson1, Michael Cooke1, Trevor A. York2, and Reginald Mann1. (1) School of Chemical Engineering and Analytical Science, University of Manchester, Po Box 88, Sackville Street, Manchester, M60 1QD, United Kingdom, (2) School of Electrical and Electronic Engineering, University of Manchester, Po Box 88, Sackville Street, Manchester, M60 1QD, United Kingdom

The work reported in this paper has illustrated, for the first time, the capability of three-dimensional EIT to monitor reactive systems under realistic process conditions and scale. The semi-batch precipitation of barium sulphate from barium chloride and sodium sulphate has been investigated in a 200 litre stirred tank reactor. Experiments have been performed using both Rushton and pitched blade turbines under a range of agitation rates with a surface feed of barium chloride. The repeatability of EIT in monitoring the reaction progress has been illustrated. The visualisation of plume structure and evolution during the semi-batch reaction has been examined in 3D. The quantification of the effect of changes in reactor level on reconstructed images has also been examined suggesting this is a limitation to the commonly used finite element approach, as only a 2 % change can cause significant effects.