Improved dynamic mixer

Abstract

A dynamic mixer comprising two mixing parts which are rotatable relative to each other about a predetermined axis of rotation, each of said mixing parts having a mixing face, between which is defined a flow path which extends between an inlet and an outlet, each of said mixing faces comprising a series of annular steps centred on the predetermined axis of rotation, having a plurality of offset and overlapping cavities formed therein, such that material moving between the mixing faces of the two mixing parts from the inlet to the outlet is transferable between overlapping cavities.

Description

technical field [0001] The present invention relates to dynamic mixers, and in particular to an improved dynamic mixer having ideal (or more ideal) mixing characteristics compared to prior art mixers. Background technique [0002] Known dynamic mixers comprise two elements or mixing parts rotatable relative to each other about a predetermined axis and between which a flow path extending between an inlet and an outlet for the materials to be mixed is defined . In this known mixer, the flow path is defined between the surfaces of the mixing element, each of which surfaces has a cavity formed in the surface. The cavities formed in one surface are offset in the axial direction relative to the cavities in the other surface, and the cavities in the one surface overlap the cavities in the other surface in the axial direction. As a result, material moving between the two surfaces is passed between overlapping cavities. Thus, in use, the material to be mixed moves between the mixi...

AI Technical Summary

Problems solved by technology

[0004] For example as described in WO 02 / 38263 A1, cavity transfer mixers of stepped conical geometry are preferred over cylindrical cavity transfer mixers for a number of reasons including, for cylindrical mixers, It is usually necessary to prepare the outer stator in a separable form to enable the formation of rows of cavities on its inner surface, whereas the complementary stepped conical geometry of each stator and rotor in the cavity transfer mixer of the stepped conical geometry The shape means that each part can be fabricated in one piece, where cavities are easily formed in both surfaces; mixers with stepped conical geometry have no open annular space between stator and rotor, unlike cylindrical mixers, which Reduced potential for material to effectively bypass the cavity and pass directly through said space; reduced potential for asymmetric transfer of mixers with stepped conical geometry, which, unlike cylindrical mixers, can result in axial backward or forward flow, which creates a stagnant mode of eventual accumulation of material within the cavity; and the lack of self-pumping and / or self-cleaning capabilities of cylindrical cavity transfer mixers, to name a few

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