The First World Congress on Industrial Process Tomography was held at the Palace Hotel, Buxton, Derbyshire from April 14th-17th 1999. Over the four days, 130 delegates registered of which about half were from the UK, one-third from continental Europe and the remainder from countries as diverse as China, Australia, USA, Canada, Brazil and Japan. Roughly one-quarter of the delegates were non-academic.
Ninety papers were presented and sessions were arranged into 4 themes
- Applications
- Algorithms
- Hardware
- Emerging Technologies
All papers were delivered orally with the majority lasting 15 minutes. A notable development from earlier meetings was the migration of applications from the workbench to industrial plant. Examples include imaging of hydrocyclones at English China Clays, pneumatic conveying at NEU Engineering, solids flow at Montell, filtration at Zeneca and nylon polymerisation at Du Pont.
A number of ‘emerging’ approaches were described including the possibility of using infra-red absorption, optical fluorescence, micro-tomography and non-circular geometries. The ‘Algorithms’ sessions identified approaches to data fusion from multi-modal systems and a move away from conventional image reconstruction algorithms.
TOMOGRAPHY PRIZE
A tomography prize, organised by Professor Maurice Beck, was awarded to the ‘best’ paper. The technical committee who, after some deliberation over a number of candidate papers, selected "Tomographic Measurements of Micro- and Macromixing Using Dual Wavelength Photometry" by Mathias Buchmann and Professor Dieter Mewes of the University of Hannover.
Selection criteria were based on novelty and inclusion of tomographic measurements. This new technique enables the measurement of the local intensity of segregation at a multitude of points inside a stirred vessel. This is achieved by injecting a mixture of an inert and a reacting dye into the vessel.
The inert dye serves as a tracer for the macromixing, whereas the vanishing of the reacting dye shows the micromixing. The concentration fields of the dyes are measured simultaneously by transluminating the vessel from three directions with superimposed laser beams of different wavelength. The light absorption by the dyes is measured with CCD-cameras and these projections are used for the tomographic reconstruction of the concentration fields.
Low Reynolds number measurements were performed with a combination of two Rushton turbines and a combination of two Pitched Blade Impellers. The combination of the Pitched Blade Impellers yields a good axial transport but a slow micromixing. The injection in the middle between the combination of the two Rushton turbines yields a faster micromixing, but the macrotransport is limited to the region between the stirrers. Example results are shown below.
