CALCINING KETTLE HAVING MEANS FOR RETURNING STACK EXHAUST GAS TO CALCINING MIXTURE

摘要

APPLICATION FORLETTERS PATENTFORCALCINING KETTLE HAVING MEANS FORRETURNING STACK EXHAUST GASTO CALCINING MIXTUREABSTRACT OF THE DISCLOSUREA calcining apparatus comprising a kettle, a heatingchamber for heating the outside of the kettle, a stack forexhausting gas from the heating chamber, a duct connected atone end to the stack and having the other end extending fora limited distance into the contents of the reaction chamberof the kettle for introducing a portion of the stack gasdirectly into the calcining reaction mixture, and means forpropelling the stack gas through the duct and into thereaction chamber of the kettle, thereby directly adding heatto the reaction mixture and accomplishing fuel conservationby recapturing and utilizing a portion of the heat from thestack gas.