Study of fluid dynamics approach to scale growth mechanism and its suppression technique

Scale is probably a more severe problem in the minerals industry than other process industries. It often leads to serious on-going technical problems and is a major cause of production loss due to equipment downtime required for descaling and cleaning operations. Gibbsite scale formation in Bayer process equipment is a natural consequence of supersaturated solutions that are generated throughout theprocess. The article describes one example applications: the fluid flow characteristics on scale deposition in a concentric reducer using Reynolds stress model are analysed. Reynolds stress simulation method to analyse the fluid dynamics behaviour of water as it flows through a concentric reducer commonly used in the Bayer plant is presented. The simulation results show a significant variation of the stream-wise and cross-stream components of the fluctuating velocity as flow passes through the concentric reducer.