Delta rotor through feed mixer

A through feed mixer comprising:

• at least two rotors mounted for rotation in opposite directions about generally parallel axes in a mixing chamber,
• each of said rotors comprising an elongated polyhedron extending axially in said mixing chamber,
• each of said elongated polyhedrons having apexes extending generally axially and being generally parallel with one another,
• a feeding device adapted to supply material to be mixed to an inlet and portion of said mixing chamber under a substantially constant pressure,
• each of said rotors having a cross-section at right angles to its axis of rotation which is derived from a regular n-sided polygon having similar peripheral portions, each peripheral portion including:
• a first, narrow section substantially circular about the axis of rotation of said rotor comprising the radially outermost portion of each of said apexes;
• a second leading section which leads into the first section to provide an acute angle between the second section and a circle defining the outer periphery of said rotor at that cross-section;
• a third section which is in part, at least, of one of the sides of the polygon;
• and
• a fourth relief section extending from the third section towards the first section of the next peripheral portion.