Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 ?m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletizer 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.

Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 ?m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletizer 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.

Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 ?m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletized 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.

Abstract: The present invention provides a method of operation and a facility for the same suppressing the generation of dioxins in the combustion exhaust gas and efficiently reclaiming heat from high temperature combustion exhaust gas when firing and reducing fines of chromium ore, iron ore, or other ore or pellets formed from dust sludge, etc. containing iron oxide or other metal oxides generated in the metal industry in a reducing rotary hearth furnace. This treats the combustion gas generated in the reducing rotary hearth furnace to make the temperature of the gas 800° C. or higher for at least a certain time, to make the concentration of the carbon monoxide not more than 200 ppm in terms of volume ratio and to achieve a sufficiently well developed turbulent state at least at one of the inside of the exhaust gas outlet duct and the vicinity of the exhaust gas outlet duct for at least a certain time, then rapidly cooling the gas.

Abstract: The present invention provides a method of operation and a facility for the same suppressing the generation of dioxins in the combustion exhaust gas and efficiently reclaiming heat from high temperature combustion exhaust gas when firing and reducing fines of chromium ore, iron ore, or other ore or pellets formed from dust sludge, etc. containing iron oxide or other metal oxides generated in the metal industry in a reducing rotary hearth furnace. This treats the combustion gas generated in the reducing rotary hearth furnace to make the temperature of the gas 800° C. or higher for at least a certain time, to make the concentration of the carbon monoxide not more than 200 ppm in terms of volume ratio and to achieve a sufficiently well developed turbulent state at least at one of the inside of the exhaust gas outlet duct and the vicinity of the exhaust gas outlet duct for at least a certain time, then rapidly cooling the gas.

Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 &mgr;m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletized 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.