Abstract: A mixing and pelletizing chamber includes a semicylindrical flexible trough of rubber or other material in which a rotor assembly mixes and pelletizes material moved from an inlet end to an outlet end. Springs are attached to the trough to resist movement of the trough in the direction of the rotation of the rotor assembly. The rotor assembly includes an axial shaft having transversely extending arms with blades at their outer ends with every fourth arm and blade being in a common plane. The blades are symmetrical and have converging flat surface to control product retention time in the pelletizer and are adjustably connected to the arms for providing adjustment of the force of the conveying action to the material in the trough. Adjustment is provided by aligned slots on opposite sides of the tubular arms receiving bolts on which the blades are carried. Optionally, the blade may nest in a semicylindrical portion of the tubular arm for angular adjustment.

Abstract: Limestone-expanding clay granules produced by charging a pulverizer and/or a mixer, with a raw material, which is high in calcium and/or magnesium, and an expanding clay binder, the expanding clay binder comprising from 1% and not more than 10% of the total charge. A portion of the material from the pulverizer is recycled back through the pulverizer, the amount recycled being determined by, among other things, the fineness of the raw material in the desired finished product. The remainder of the material from the pulverizer is caused to pass through a granulator, a dryer-cooler, and a finished product screen means. Fines from the finished product screen means are recycled directly to the pulverizer. Oversize material from the finished product screen is recycled to the pulverizer or to separate crusher and then back over the finished product screen means, where fines are removed and sent back to the pulverizer.