Scale-Up
also known as process scale-up · design extrapolation
Scale-up increases a process's capacity while preserving the conditions that made it work. It is not simple geometric enlargement, because mixing intensity, heat transfer per unit volume, residence time distribution and settling behaviour all change with size. The reliable approach holds one dimensionally-derived criterion constant — mixing power per unit volume, or a settling velocity — and accepts that other quantities must change.
Why it matters in practice
Most process failures in this industry are scale-up failures rather than chemistry failures. Units whose behaviour can be measured directly at small scale, such as mixer-settlers, scale up far more predictably than units whose performance per metre is empirical, such as columns.
Where this appears on this site
Calculators that use this
Equipment referenced in this entry
Pilot Scale Mixer Settler
8 Specifications · mixer settler
Laboratory Evaporation Crystallization Unit
7 Specifications · evaporation crystallization equipment
Related terms
Reference entry GL-SCALE-UP. Definitions on this page describe engineering practice in hydrometallurgical process design; they are not a substitute for test work on your own material.