Flash ironmaking drop tube furnace system

Abstract

A flash ironmaking method is for use with a drop tube furnace that includes a susceptor and a muffle. The method includes feeding particles into the drop tube furnace, introducing hydrogen gas into the drop tube furnace so that it flows parallel to the falling particles, heating a susceptor using induction heating, so that the particles are heated as they fall through the susceptor, heating a muffle, to maintain the temperature of the particles as they fall through the muffle, and cooling the particles and hydrogen gas after they pass through the muffle.

We claim: 
     
         1 . A flash ironmaking method, comprising:
 feeding particles into a drop tube furnace;   introducing hydrogen gas into the drop tube furnace so that it flows parallel to the falling particles;   heating a susceptor using induction heating, so that the particles are heated as they fall through the susceptor;   heating a muffle, to maintain the temperature of the particles as they fall through the muffle; and   cooling the particles and hydrogen gas after they pass through the muffle.   
     
     
         2 . A flash ironmaking method according to  claim 1 , wherein the heating of the muffle comprises heating using at least one resistance heater. 
     
     
         3 . A flash ironmaking method according to  claim 1 , wherein the feeding comprises feeding the particles with a volume flow rate that produces a dilute particle curtain. 
     
     
         4 . A flash ironmaking method according to  claim 1 , wherein the feeding comprises feeding the particles into the drop tube furnace in multiple locations to produce multiple particle curtains. 
     
     
         5 . A flash ironmaking method according to  claim 1 , further comprising separating the particles from the hydrogen gas.