Chemical Engineering Science, Vol.205, 106-120, 2019
High pressure dewatering rolls: Comparison of a novel prototype to existing industrial technology
The optimisation of solid-liquid separation or dewatering processes for more efficient operation and reuse of material streams is of high importance. Suspension dewatering aims to increase the solids concentration and exhibits two limitations: the dewatering extent and the rate. A novel dewatering device, called High Pressure Dewatering Rolls (HPDR), has been developed. It combines shear and compression while maintaining a short filtration length between the rollers. The HPDR challenges the limitations of dewatering processes through the application of high pressures and induced shear to aid the extent of dewatering, and a short filtration length to allow fast dewatering. A prototype HPDR is described along with a performance assessment for different operating conditions as well as a comparison against state-of-the-art technology for a variety of industrial suspensions. The results demonstrate that the HPDR prototype, without any optimisation, outperforms or achieves comparable cake solids concentrations to existing equipment in a continuous mode of operation. Analysis of energy consumption and throughput remain outstanding and require further prototype development. (C) 2019 Published by Elsevier Ltd.
Keywords:Dewatering;Solid-liquid separation;Shear enhanced compression;Industrial comparison;High pressure dewatering rolls