A TREATMENT OF HIGH VOLATILE AND DECREPITABLE MANGANESE ORES IN A VERTICAL FURNACE BY PARTIAL REDUCTION ROASTING UTILIZING OFF-GAS EMITS FROM SUB-MERGED ARC FURNACE FOR PRODUCTION OF FERRO-MANGANESE

摘要

This invention relates to a process of upgradation of high volatile and decrepitatable managanese ores in a vertical shaft furnace by partial reduction roasting utilising sub-merged are furnace (SAF) off-gas for production of ferromanganese comprising the steps of charging the cleaned and warm off-gas from a sub-merged are furnace (SAF) in the gaseous reduction zone of a vertical shaft furnace charged with decrepitable manganese ores to simultaneously accomplish cooling of the outgoing charge material and pre reduce it partially by dint of carbon monoxide containing in the charged ore, the said upcoming gas is carried through the dissociation zone of the shaft furnace wherein the MnO2 content of the ore is dissociated to Mn3O4 at 570-600° C and liberates free oxygen which is autogenously utilized for combusting the residual carbon monoxide and hydrogen gases available in the off-gas of the sub-merged are furnace (SAF) in the combustion zone maintained at 600-900° C, the heat produced in the combustion zone being utilized for drying, preheating and dissociation of the ores, the ores discharged at the bottom of the furnace being screened to separate fines which are briquetted and sintered and the dried partially reduced manganese pre obtained, to be charged in the sub-merged are furnace (SAF) for producing Ferromanganese optimisingly.