Thickener dynamic analysis, accounting for compression effects

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Abstract

The dynamic behaviour of the thickening zone of a continuous thickener has been analysed, and numerical solutions of the resulting differential equations obtained for a range of conditions. For high throughput, low underflow concentration operation, mechanical (compressive) support of the solids can be very small, providing that sludge funnelling is taken into account. Neglecting mechanical support in such cases gives results which are fairly accurate, but limited by the presence at the top of the sediment of a shallow layer in which mechanical support is significant. For low throughput, high underflow concentration operation hydrodynamic support of the solids can be small, and its neglect gives again fairly accurate results. In general, both hydrodynamic and mechanical support of solids have to be taken into account.

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