Mixing apparatus of the CDDM- and/or CTM-type, and its use
A distributive and dispersive mixing apparatus comprising two confronting surfaces ( 1,2 ) having cavities ( 3 ) therein which on relative motion of the surfaces function as a cavity transfer mixer (CTM) or controlled deformation dynamic mixer (CDDM) or both, CHARACTERISED IN THAT the normal separation of the confronting surfaces varies in the direction of bulk flow, so as to define a plurality of regions of successive closer and wider spacing of the confronting surfaces.
1. A distributive and dispersive mixing apparatus comprising:
a material inlet port ( 4 ) and a material outlet port ( 4 ) having a direction of bulk material flow defined therebetween; and
two confronting surfaces ( 1 , 2 ), each of the confronting surfaces having discrete cavities ( 3 ) therein, which on relative motion of the surfaces ( 1 , 2 ) function as a cavity transfer mixer or controlled deformation dynamic mixer or both,
CHARACTERISED IN THAT a normal separation of the two confronting surfaces ( 1 , 2 ), which is the separation of said surfaces in the absence of said discrete cavities ( 3 ), varies in the direction of bulk material flow, so as to define a plurality of regions of successively closer (Y I , Y II , Y III , Y IV ) and wider spacing (X I , X II , X III , X IV , X V ) of the confronting surfaces ( 1 , 2 ) in the direction of bulk material flow, the regions of closer spacing (Y I , Y II , Y III , Y IV ) being defined by annular rings and the regions of wider spacing (X I , X II , X III , X IV , X V ) being defined by annular channels between successive annular rings,
wherein a plurality of the discrete cavities ( 3 ) are circumferentially disposed in at least one of the annular channels,
whereby the separation of said confronting surfaces ( 1 , 2 ) in the annular channels is greater than the normal separation of the confronting surfaces ( 1 , 2 ) in adjoining annular rings by a factor of at least 2;
and wherein the annular rings are not by passed by flow in and through the discrete cavities ( 3 ), such that the apparatus functions as a controlled deformation dynamic mixer.
2. A mixing apparatus according to claim 1 wherein the confronting surfaces ( 1 , 2 ) comprise generally cylindrical surfaces.
3. A mixing apparatus according to claim 1 wherein the confronting surfaces ( 1 , 2 ) comprise generally conical surfaces.
4. A mixing apparatus according to claim 1 wherein the confronting surfaces ( 1 , 2 ) comprise generally disk-like surfaces.
5. A distributive and dispersive mixing apparatus according to claim 1 wherein the separation of the confronting surfaces ( 1 , 2 ) in the annular channels is greater than the normal separation of the confronting surfaces ( 1 , 2 ) in adjoining annular rings by a factor of at least 3 to 20.
6. A mixing device apparatus according to claim 1 further comprising at least one cage-like member disposed between the confronting surfaces ( 1 , 2 ), the surfaces of the cage-like member conforming in profile to the confronting surfaces ( 1 , 2 ) against which they are respectively disposed.
7. A mixing device apparatus according to claim 1 further comprising regions of axially disposed confronting surfaces ( 1 , 2 ) which alternate with regions of radially disposed confronting surfaces ( 1 , 2 ) thereby preventing any leakage flow through the mixer.