Removal of particles from highly viscous liquids with hydrocyclones

Author-Highlights
• Quality performance-data for a hydrocyclone acting on viscous liquids are given.
• Liquid viscosity effects on hydrocyclone cut size and pressure drop are elucidated.
• A model, predicting the performance well, is given in full.
• CFD simulations show that viscosity effects can be simulated reasonably with LES.

In this paper the performance characteristics, expressed as cut-size, grade-efficiency curve and pressure drop, have been determined for a hydrocyclone acting on highly viscous liquids. These results are of high quality and can serve as a benchmark for simulations and model predictions. To understand the results, CFD, large-eddy simulations of the flowpattern and pressure drop have been carried out, among other things to determine the vortex intensity as a function of liquid viscosity. A version of a main-stream cyclone model has been identified that predicts the trend in hydrocyclone performance with liquid viscosity well, both in terms of separation efficiency and pressure drop. This model is given in full, providing a valuable tool in evaluating the potential of hydrocyclone technology for new and unconventional separation duties.