IMPROVEMENTS IN CALCINATION APPARATUS

摘要

An improved gypsum calciner comprises a conical kettle (60) into which hot gas is introduced from a combustion chamber (72) through a plurality of dip tubes (80). Apparatus according to the invention allows the hot gas to be at a lower temperature when contacting the gypsum in the kettle than is usual, and results in lower levels of insoluble anhydrite in the plaster produced.