A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.

A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.

A rotary hearth furnace includes a unit that supplies an agglomerate onto a hearth of the rotary hearth furnace, a unit that discharges a heated substance which has been heated in the rotary hearth furnace to the outside of the furnace, and a unit that discharges an exhaust gas in the rotary hearth furnace to the outside of the furnace. The rotary hearth furnace has a heating section and a non-heating section. The unit that discharges an exhaust gas to the outside of the furnace is provided in the non-heating section. A unit that takes an outside air into the furnace is provided in the non-heating section and on an upstream side in a flow direction of the exhaust gas from the unit that discharges exhaust gas to the outside of the furnace.

A rotary hearth furnace includes a unit that supplies an agglomerate onto a hearth of the rotary hearth furnace, a unit that discharges a heated substance which has been heated in the rotary hearth furnace to the outside of the furnace, and a unit that discharges an exhaust gas in the rotary hearth furnace to the outside of the furnace. The rotary hearth furnace has a heating section and a non-heating section. The unit that discharges an exhaust gas to the outside of the furnace is provided in the non-heating section. A unit that takes an outside air into the furnace is provided in the non-heating section and on an upstream side in a flow direction of the exhaust gas from the unit that discharges exhaust gas to the outside of the furnace.

A method for producing direct reduced metal material includes charging metal material to be reduced into a furnace space; evacuating an existing atmosphere from the furnace space so as to achieve an underpressure inside the furnace space; providing, in a main heating step, heat and hydrogen gas to the furnace space, so that heated hydrogen gas heats the charged metal material to a temperature high enough so that metal oxides present in the metal material are reduced, in turn causing water vapor to be formed; and condensing and collecting the water vapor in a condenser below the charged metal material. The providing of heat and hydrogen gas, and the condensing and collecting, are performed at least until a hydrogen atmosphere overpressure has been reached inside the furnace space, and so that no hydrogen gas is evacuated from the furnace space until the overpressure has been reached.

Method and system for producing direct reduced metal material, comprising the steps: a) charging metal material to be reduced into a furnace space (120); b) evacuating an existing atmosphere from the furnace space to achieve a gas pressure of less than 1 bar therein, c) providing heat and hydrogen gas into the furnace space, so that heated hydrogen gas heats the charged metal material to a temperature high enough so that metal oxides present in the metal material are reduced, in turn causing water vapour to be formed, which hydrogen gas provision is performed so that a pressure of more than 1 bar builds up inside the furnace space; and d) before evacuating the built up overpressure, condensing and collecting the water vapour formed in step c in a condenser (160) below the charged metal material. The invention is characterised in that it further comprises the step e) before evacuating the build up overpressure, providing a carbon-containing gas to the furnace space, so that the heated and reduced metal material is carburized by said carbon-containing gas.

The invention relates to a process of melting ferrous metal using a gaseous fuel, a liquid fuel or a pulverized solid fuel in a cokeless horizontal reverberatory furnace (FIG. 1) consisting of a hearth (1), an sloped melting chamber (2) a vertical refractory grid (4), a burner (3), a recuperator or regenerator (5) to transfer heat from waste gas and products of combustion to fresh oxygen bearing gases, whereas a burner system is installed on the hearth for combustion of the fuel and oxygen bearing gas, the hearth under the burner acts as a superheater to achieve the temperature necessary for alloying and to receive the molten metal cascading from the sloped melting chamber, the sloped melting chamber being fed from one end by the rising gas products of combustion and in which the waste gases are subject to post-combustion of carbon monoxide and volatiles before passing through a recuperator or a regenerator to pre-heat the oxygen bearing gases necessary for combustion.

The invention relates to a process of melting ferrous metal using a gaseous fuel, a liquid fuel or a pulverized solid fuel in a cokeless horizontal reverberatory furnace (FIG. 1) consisting of a hearth (1), an sloped melting chamber (2) a vertical refractory grid (4), a burner (3), a recuperator or regenerator (5) to transfer heat from waste gas and products of combustion to fresh oxygen bearing gases, whereas a burner system is installed on the hearth for combustion of the fuel and oxygen bearing gas, the hearth under the burner acts as a superheater to achieve the temperature necessary for alloying and to receive the molten metal cascading from the sloped melting chamber, the sloped melting chamber being fed from one end by the rising gas products of combustion and in which the waste gases are subject to post-combustion of carbon monoxide and volatiles before passing through a recuperator or a regenerator to pre-heat the oxygen bearing gases necessary for combustion.

An apparatus for manufacturing molten metal has a stationary electric furnace, a raw material charging chute, and exhaust duct and a secondary combustion burner in the furnace top, and a shock generator. The raw material charging chute is in one end of the furnace in a width direction and an electric heating region is spaced from the raw material charging chute in the width direction. A raw material layer having a sloping surface extends downward from the one end of the furnace having the raw material charging chute toward the electric heating region, the sloping surface supporting a metal agglomerate raw material layer. The shock generator is provided at least partially within the raw material and extends to the sloping surface, to be in contact with the metal agglomerate raw material layer, and to mechanically overcome hanging of the metal agglomerate raw material layer on the sloping surface.

An apparatus for manufacturing molten metal has a stationary electric furnace, a raw material charging chute, and exhaust duct and a secondary combustion burner in the furnace top, and a shock generator. The raw material charging chute is in one end of the furnace in a width direction and an electric heating region is spaced from the raw material charging chute in the width direction. A raw material layer having a sloping surface extends downward from the one end of the furnace having the raw material charging chute toward the electric heating region, the sloping surface supporting a metal agglomerate raw material layer. The shock generator is provided at least partially within the raw material and extends to the sloping surface, to be in contact with the metal agglomerate raw material layer, and to mechanically overcome hanging of the metal agglomerate raw material layer on the sloping surface.