Process and plant for the direct reduction of particulate iron-oxide-containing material

• Main Authors: MILLIONIS KONSTANTIN, ZIRNGAST JOHANN, ZELLER SIEGFRIED, WHIPP ROY HUBERT, KEPPLINGER LEOPOLD WERNER, REIDETSCHLAGER JOHANN, SCHENK JOHANNES
• Format: Patent
• Language: English
• Published: 29.08.2002
• Edition: 7
• Subjects: CHEMISTRY; MANUFACTURE OF IRON OR STEEL; METALLURGY; METALLURGY OF IRON

In a process for the direct reduction of particulate iron-oxide-containing material by fluidization, a synthesis as is introduced as a reducing gas into several fluidized bed zones consecutively arranged in series for the reducing gas and the reducing as is conducted from one fluidized bed zone to another fluidized bed zone in counterflow to the particulate iron-oxide containing material. In order to reduce operating costs and, in particular, the energy demand, a temperature of the iron-oxide-containing material of either below 400° C. and, preferably, below 350° C., or above 580° C. and, preferably about 650° C., or a temperature ranging from 400° C. to 580° C. is adjusted, in the first fluidized bed zone, wherein, at a temperature adjustment to below 400° C., the temperature range between 400° C. and 580° C. in the fluidized bed zone following the first fluidized bed zone in the flow direction of the iron-oxide-containing material is sassed through within a period of 10 minutes and, preferably within 5 minutes. and wherein, at a temperature adjustment to above 580° C., the temperature range between 400° C. and 580° C. is passed through within a period of time of maximally 10 minutes and, preferably, 5 minutes, and wherein. Furthermore, at a temperature adjustment in the range of from 400° C. to 580° C., the iron-oxide-containing material remains within that temperature range for a maximum of 10 minutes and. preferably, 5 minutes and is passed on into the fluidized bed zone following next immediately after having reached the desired temperature (FIG. 1).