2. Liquid-liquid extractors with individual stages

In this type of device, the interfacial exchange area of the mixer is created either by mechanical agitation in a stirred tank, or by any other mixing device such as static mixers, jet mixers or nozzle mixers, which use the pressure drop energy of fluids moving in a pipe.

In the decanter, subsequent separation of the mixed phases is achieved either by gravity settling in empty tanks or tanks equipped with coalescence gas pedals (packing, fibrous beds, electrocoalescers), or by centrifugal settling in hydrocyclones or centrifugal decanters.

In theory, any combination of mixer and separator is possible. In industrial practice, stirred tanks and gravity decanters have long been the norm. More recently, some hydrometallurgical processes have used static mixers and centrifugal decanters. Gravity decanters are almost always fitted with coalescing...