Rotary mixer

A mixing device for the mixing of two or more liquids comprising a shell body having upstream and downstream ends and an internal cavity, said cavity having a longitudinal axis and substantially circular cross section, a shaft rotatably housed within said shell body and having a longitudinal axis which coincides with said longitudinal axis of said internal cavity, said shaft having slotted grooves configured along a portion of its surface for receiving the liquids to be mixed from inlets located within the shell body, a narrow annular gap region formed between the outer surface of the shaft and the inner surface of the internal cavity in the portion of the shaft containing said slotted grooves such that said liquids tend to smear in said narrow angular gap region, a drive shaft for connection to a suitable device for rotating said shaft within said internal cavity and inlet means located within said shell body for the introduction of two or more liquids to be mixed proximate the upstream end of said shell body and a liquid exit means located proximate the downstream end of said shell body for removing said two or more liquids.