METHOD FOR REMOVING SULFUR OXIDES FROM HOT EXHAUST GASES PRODUCED DURING MANUFACTURE OF REDUCED IRON PELLETS

摘要

METHOD FOR REMOVING SULFUR OXIDES FROMHOT EXHAUST GASES PRODUCED DURINGMANUFACTURE OF REDUCED IRON PELLETSABSTRACT OF THE DISCLOSUREA method for removing sulfur oxides from hot exhaustgases produced during manufacture of reduced iron pellets,which comprises: using a grate-kiln type furnace includinga pretreatment furnace comprising a drying zone, a preheatingzone following said drying zone, a hardening zone followingsaid preheating zone, and a travelling grate passing sequen-tially through said zones, and a rotary kiln receiving theoutput material from said hardening zone; feeding green pelletsprepared mainly from a dust principally comprising iron oxidesdischarged from an iron and steelmaking metallurgical furnaceand/or an iron ore fine, together with a granular soliddesulfurizing agent, onto the entry side of said travellinggrate, said dust and/or said iron ore fine containing aconsiderable amount of sulfur oxides; passing said green pelletsand said solid desulfurizing agent sequentially through saiddrying zone, said preheating zone and said hardening zone onsaid travelling grate to said rotary kiln, while passing hotexhaust gases produced in said rotary kiln, in a directionopposite to the travelling direction of said green pellets- 1 -and said solid desulfurizing agent, sequentially throughsaid hardening zone, said preheating zone and said dryingzone, thereby drying, preheating and hardening said greenpellets in travel on said travelling grate through saidzones, and simultaneously preheating said solid desulfurizingagent sufficiently to cause said solid desulfurizing agent toperform statisfactorily the function thereof to absorb thesulfur oxides contained in said hot exhaust gases beforecharging into said rotary kiln; and, reducing the hardenedpellets from said hardening zone in said rotary kiln tomanufacture reduced iron pellets, and removing by absorptionthe sulfur oxides from said hot exhaust gases produced insaid rotary kiln during reducing said hardened pellets, bymeans of said preheated solid desulfurizing agent.- 2 -