Feedwells are fluid dynamic control components which distribute multiphase feed streams (solids, liquids and sometimes gases) into separation or thickening vessels.
The challenge feedwells tackle is to disperse a high velocity feed stream into a much larger vessel, spreading the feed evenly across the vessel with minimal mixing to maximize the separation performance.
A typical slurry stream might have velocities on the order of 5 m/s in the feed pipe and be entering a separation vessel with 1000x larger cross-sectional area and average velocities of only a few mm/s. The feedwell must be designed to minimize wear on both the feedwell itself and vessel while accommodating a wide range of turn-up and turn-down conditions. In some cases, they also combine multiple independent input streams with varying compositions.
Coanda has performed many feedwell design and optimization projects for a numerous clients and process applications using both computational fluid dynamics (CFD) and laboratory scale physical modelling tools. Several patents have been issued to our clients on Coanda feedwell designs.