An integrated rotary mixer and disperser head comprising: - a drive shaft configured to be connected to a drive motor, - a cylindrical mixing chamber coaxial with and rigidly connected to the drive shaft and having through its peripheral wall a plurality of discharge openings, - a first plurality of equally angularly spaced impeller blades at one axial end of said mixing chamber, each of said first plurality of impeller blades having a leading edge situated completely outside the mixing chamber and disposed axially outside for said one end, and a trailing portion having a trailing edge disposed axially inward for said leading edge, - a second plurality of equally angularly spaced impeller blades at the other axial end of said mixing chamber, each of said second plurality of impeller blades having a leading edge situated completely outside the mixing chamber and disposed axially outside for said other end, and a trailing portion having a trailing edge disposed axially inward for said leading edge, - the leading edge of each of said first plurality of impeller blades forming part of a first shear part, the radially inner end thereof being rigidly connected to said drive shaft and the radially outer end thereof being rigidly connected to said one axial end of the mixing chamber, - the leading edge of each of said second plurality of impeller blades forming part of a second shear part, the radially outer end thereof being rigidly connected to said other axial end of the mixing chamber, characterized by - a plurality of equally angularly spaced shear arms situated completely outside the mixing chamber and radially extending from said drive shaft, - the radially inner end of each of said plurality of equally spaced shear arms being rigidly connected to said drive shaft, and the radially outer end of each of said plurality of equally spaced shear arms being rigidly connected to a respective one of the radially outer end of one of the first shear part, - each of said shear arms having a sharpened leading edge and a trailing edge. - a drive shaft configured to be connected to a drive motor, - a cylindrical mixing chamber coaxial with and rigidly connected to the drive shaft and having through its peripheral wall a plurality of discharge openings, - a first plurality of equally angularly spaced impeller blades at one axial end of said mixing chamber, each of said first plurality of impeller blades having a leading edge situated completely outside the mixing chamber and disposed axially outside for said one end, and a trailing portion having a trailing edge disposed axially inward for said leading edge, - a second plurality of equally angularly spaced impeller blades at the other axial end of said mixing chamber, each of said second plurality of impeller blades having a leading edge situated completely outside the mixing chamber and disposed axially outside for said other end, and a trailing portion having a trailing edge disposed axially inward for said leading edge, - the leading edge of each of said first plurality of impeller blades forming part of a first shear part, the radially inner end thereof being rigidly connected to said drive shaft and the radially outer end thereof being rigidly connected to said one axial end of the mixing chamber, - the leading edge of each of said second plurality of impeller blades forming part of a second shear part, the radially outer end thereof being rigidly connected to said other axial end of the mixing chamber, characterized by - a plurality of equally angularly spaced shear arms situated completely outside the mixing chamber and radially extending from said drive shaft, - the radially inner end of each of said plurality of equally spaced shear arms being rigidly connected to said drive shaft, and the radially outer end of each of said plurality of equally spaced shear arms being rigidly connected to a respective one of the radially outer end of one of the first shear part, - each of said shear arms having a sharpened leading edge and a trailing edge.