Abstract: A method and apparatus for controlling the viscosity of slag contained in a rotary incinerating kiln by detecting the position at which the slag exits the outlet of the kiln, thereby determining changes in the viscosity of the slag. If the viscosity deviates from a predetermined range of values, appropriate additives are supplied to the slag for bringing the viscosity back to within the range of the predetermined values. There is also disclosed a method and apparatus for measuring viscosity as "angular" viscosity.

Abstract: A recycle conduit insulation assembly for use with a helical recycle conduit of a rotary reactor of the type having a rotating, horizontally-oriented, cylindrical chamber for burning materials therein and a quantity of particulate, inorganic material within the chamber for conveying heat energy to material to be burned. The insulation assembly includes a plurality of shell elements, each comprising a cylinder enclosing a portion of the conduit and being arranged in overlapping relation, a plurality of mounting rings, each attached to and extending radially from the conduit and having a T-shape in section for supporting the shell elements at ends thereof, and a pumpable refractory mixture substantially filling the insulating space between the shell elements and conduit.

Abstract: A rotary reactor of the type having a cylindrical, horizontally-oriented chamber lined with a refractory for burning materials therein and a plurality of trough-like lifters, extending along the interior surface of the chamber, for lifting and dumping sand in the chamber as the chamber rotates, a long-wearing lifter assemble which minimizes intrusion of contaminants between the lifter and the refractory.