Stage Efficiency
also known as mixer-settler efficiency · Murphree efficiency
Stage efficiency compares the concentration change an actual stage delivers with the change a perfectly mixed, perfectly settled equilibrium stage would deliver. A well-designed mixer-settler reaches 90% or more. Losses come from incomplete mixing in the mixer, short-circuiting in the settler, and entrained droplets carried forward in the wrong phase.
Why it matters in practice
Because it is measured stage by stage, stage efficiency turns a mixer-settler circuit into an instrument as well as a process unit. A gradual fall in efficiency across a campaign usually points at a physical cause — crud build-up, worn impellers, or changed feed chemistry — long before product quality drifts.
Where this appears on this site
Equipment referenced in this entry
Lab Scale Mixer Settler
8 Specifications · mixer settler
Pilot Scale Mixer Settler
8 Specifications · mixer settler
Related terms
Reference entry GL-STAGE-EFFICIENCY. Definitions on this page describe engineering practice in hydrometallurgical process design; they are not a substitute for test work on your own material.