Abstract: In a process for reducing iron-ore-containing particulate material in at least a two-stage process, reducing gas is conducted through at least two reaction zones consecutively arranged in series and formed by a moving particulate material and the particulate material passes through the reaction zones in reverse order to the reducing gas, with the particulate material being heated in the reaction zone arranged first for the particulate material and being reduced in the further reaction zone.

Abstract: In a process for reducing iron-ore-containing particulate material in at least a two-stage process, reducing gas is conducted through at least two reaction zones consecutively arranged in series and formed by a moving particulate material and the particulate material passes through the reaction zones in reverse order to the reducing gas, with the particulate material being heated in the reaction zone arranged first for the particulate material and being reduced in the further reaction zone.

Abstract: In a process for reducing iron-ore-containing particulate material in at least a two-stage process, reducing gas is conducted through at least two reaction zones consecutively arranged in series and formed by a moving particulate material and the particulate material passes through the reaction zones in reverse order to the reducing gas, with the particulate material being heated in the reaction zone arranged first for the particulate material and being reduced in the further reaction zone.

Abstract: In a process for the direct reduction of particulate iron-oxide-containing material by fluidization, a synthesis gas is introduced as a reducing gas into several fluidized bed zones consecutively arranged in series. The reducing gas is conducted from one fluidized bed zone to another fluidized bed zone in counterflow to a flow of particulate iron-oxide containing material through the fluidized bed zones. In order to reduce operating costs and, in particular, the energy demand, various process parameters are varied according to the temperature of the iron-oxide-containing material in the first fluidized bed zone being adjusted to be below 400° C. (and, preferably, below 350° C.), above 580° C. (and preferably about 650° C.), or to a temperature within the range of from 400° C. to 580° C. If the temperature of the iron-oxide-containing material in the first fluidized bed zone is maintained to be below 400° C.

Abstract: 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.

Abstract: A process for the direct reduction of particulate iron-oxide-containing material by fluidization. A synthesis gas is introduced as a reducing gas into several fluidized bed zones consecutively arranged in series for the reducing gas. The reducing gas 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, the temperature of the iron-oxide-containing material is adjusted in the first fluidized bed zone to be either below 400° C. (and, preferably, below 350° C.), or above 580° C. (and preferably about 650° C.), or to a temperature ranging from 400° C. to 580° C. If the temperature of the iron-oxide-containing material in the first fluidized bed zone is adjusted to be below 400° C., the temperature range in the following fluidized bed zone between 400° C. and 580° C.

Abstract: In a process for producing sponge iron by direct reduction of iron-oxide-containing material, synthesis gas is mixed with top gas forming in the direct reduction of the iron-oxide-containing material and is utilized as a CO- and H.sub.2 -containing reducing gas for direct reduction and for heating the iron-oxide-containing material to a reduction temperature. To be able to save energy in an economically efficient manner when producing steel, especially in the refining process, direct reduction is carried out as follows: (1) in addition to the reducing gas, a carbon-containing gas, such as natural gas, or a gas having higher hydrocarbons is utilized for reduction; (2) the iron-oxide-containing material for a predetermined period of time exceeding the period necessary for complete reduction is exposed to the reducing gas and to the additionally supplied carbon-containing gas, and (3) a CO/CO.sub.2 ratio ranging between 2 and 5, preferably a ratio in excess of 2.5, is adjusted in the reducing gas.