Reversed interstitial paddles

An inner drum for use in a dryer/mixer in connection with the production of an aggregate-mix, wherein the dryer/mixer includes a fixed outer drum surrounding the inner drum such that the inner drum may rotate within the outer drum, a mixing chamber formed between an outer surface of the inner drum and an inner surface of the outer drum, an aggregate inlet through which virgin aggregate may be passed into the mixing chamber, and a mix outlet through which the aggregate mix may be passed out of the mixing chamber, the inner drum further comprising:

• a plurality of mixing paddles disposed on the outer surface of the inner drum and arranged in a plurality of rows, wherein the mixing paddles are configured to rotate through the mixing chamber as the inner drum rotates within the outer drum and to move the aggregate mix in a flow direction F away from the aggregate inlet as the inner drum rotates in rotation direction R;
• an interstitial space formed between each adjacent pair of rows of mixing paddles;
• a plurality of material leads that extend along the mixing chamber and along which aggregate material preferentially travels as a result of a location and orientation of the plurality of mixing paddles;
• and
• at least one interstitial mixing paddle disposed on the outer surface of the inner drum and located in one of the interstitial spaces and also positioned at one of the material leads, wherein the interstitial mixing paddle is configured to rotate through the mixing chamber as the inner drum rotates within the outer drum and to move the aggregate mix in a retrograde flow direction F′ towards the aggregate inlet as the inner drum rotates in rotation direction R.