Patent ID: 7033417

Claim:
A method for reduction of fine ores, in which prepared fine ores pass from the top downwards through a multi-stage gas suspension preheater generally in countercurrent flow to rising hot gases and are preheated and calcined in at least one upper heat exchanger stage and then are subjected to a reducing heat treatment in at least one lower heat exchanger stage with a reducing agent being added into the delivered hot gas stream, wherein the principal part of the reducing heat treatment of the preheated and calcined fine ores is carried out in a reactor loop specially constructed in the lowest heat exchanger stage of the gas suspension preheater, said reactor loop has an uptake conduit section and a curved section adjoining the uptake conduit section and with which the reactor loop opens into at least one precipitating cyclone which is disposed downstream, and for this purpose a hot gaseous reducing agent is introduced into the rising hot gas stream.