A smelting apparatus that includes (a) a smelting vessel (4) that is adapted to contain a bath of molten metal and slag and (b) a smelt cyclone (2) for pre-treating a metalliferous feed material positioned above and communicating directly with the smelting vessel The apparatus also includes an oft-gas duct (9) extending from the smelt, cyclone for discharging an off-gas from the smelt cyclone. The off-gas duct has an inlet section (18) that extends upwardly from the smelt cyclone and is formed to cause off-gas to undergo a substantial change of direction as it flows through the inlet section of the off-gas duct.

Provided is a method for manufacturing reduced iron which includes the steps of: i) drying ores in an ore drier; ii) supplying the dried ores to at least one reduction reactor; iii) reducing the ores in the at least one reduction reactor and manufacturing reduced iron; iv) discharging exhaust gas by which the ores are reduced in the reduction reactor; v) branching the exhaust gas and providing the branched exhaust gas as ore feeding gas; and vi) exchanging heat between the exhaust gas and the ore feeding gas and transferring the sensible heat of the exhaust gas to the ore feeding gas. In the supplying the dried ores to the at least one reduction reactor, the dried ores are supplied to the at least one reduction reactor by using the ore feeding gas.

The invention discloses a multi-stage suspension magnetizing roasting-magnetic separation system and method for refractory iron ore, which belongs to the field of mineral processing technology. This system comprises multistage suspension preheater, multistage suspension oxidizer, multistage suspension redactor, on-line grade analyzer, ore-like splitter, magnetic separator, dust remover, roots blower and other components and connection modes. The refractory iron ore treated by the present method can be produced to homogeneous magnetite or maghemite accurately, and through magnetic separation, on-line grade analyzer detection and ore-like splitter, the concentrate powder which reach the set grade can be obtained, and the unqualified ore powder enters the next stage of oxidation-reduction-magnetic separation-split treatment. Through the present system and method, products with different roasting quality can be obtained, and can avoid the phenomenon of over burning or under burning occurring in the past process and equipment.

The invention discloses a multi-stage suspension magnetizing roasting-magnetic separation system and method for refractory iron ore, which belongs to the field of mineral processing technology. This system comprises multistage suspension preheater, multistage suspension oxidizer, multistage suspension redactor, on-line grade analyzer, ore-like splitter, magnetic separator, dust remover, roots blower and other components and connection modes. The refractory iron ore treated by the present method can be produced to homogeneous magnetite or maghemite accurately, and through magnetic separation, on-line grade analyzer detection and ore-like splitter, the concentrate powder which reach the set grade can be obtained, and the unqualified ore powder enters the next stage of oxidation-reduction-magnetic separation-split treatment. Through the present system and method, products with different roasting quality can be obtained, and can avoid the phenomenon of over burning or under burning occurring in the past process and equipment.

The disclosure relates to a process for the production of sponge iron from iron ore that includes the steps: charging iron ore into a direct reduction shaft; introducing a hydrogen-rich reducing gas into the direct reduction shaft in order to reduce the iron ore and produce sponge iron; removing a top gas from the direct reduction shaft; dividing the top gas into a recycle stream and a bleed-off stream; processing the bleed-off stream through a separation unit to provide a hydrogen-enriched off-stream and an inert-enriched off-stream; and introducing the recycle stream and the hydrogen-enriched off-stream as constituent parts of the hydrogen-rich reducing gas to the direct reduction shaft. The disclosure further relates to a system for the production of sponge iron.

The disclosure relates to a process for the production of sponge iron from iron ore that includes the steps: charging iron ore into a direct reduction shaft; introducing a hydrogen-rich reducing gas into the direct reduction shaft in order to reduce the iron ore and produce sponge iron; removing a top gas from the direct reduction shaft; dividing the top gas into a recycle stream and a bleed-off stream; processing the bleed-off stream through a separation unit to provide a hydrogen-enriched off-stream and an inert-enriched off-stream; and introducing the recycle stream and the hydrogen-enriched off-stream as constituent parts of the hydrogen-rich reducing gas to the direct reduction shaft. The disclosure further relates to a system for the production of sponge iron.

A process for steel production that includes: production of sponge iron from iron oxide-containing starting material by direct reduction with reduction gas, wherein the reduction gas has at least 20% by volume of hydrogen H.sub.2, and production of an iron melt having a carbon content of 1-5% by mass from the sponge iron.

Sponge iron is subjected to a treatment that includes: energy input and addition of additives to produce a melt and a slag, wherein the energy input is effected substantially from electricity and wherein the slag has a basicity B2 of less than 1.3, preferably less than 1.25, particularly preferably less than 1.2, adjustment of the carbon content in the melt, reduction of at least a sub-amount of the iron oxides present in the sponge iron

The slag is separated during and/or after the treatment.

A process for steel production that includes: production of sponge iron from iron oxide-containing starting material by direct reduction with reduction gas, wherein the reduction gas has at least 20% by volume of hydrogen H.sub.2, and production of an iron melt having a carbon content of 1-5% by mass from the sponge iron.

Sponge iron is subjected to a treatment that includes: energy input and addition of additives to produce a melt and a slag, wherein the energy input is effected substantially from electricity and wherein the slag has a basicity B2 of less than 1.3, preferably less than 1.25, particularly preferably less than 1.2, adjustment of the carbon content in the melt, reduction of at least a sub-amount of the iron oxides present in the sponge iron

The slag is separated during and/or after the treatment.

An apparatus for manufacturing molten iron includes: an iron ore-mixing/pre-reducing furnace receiving and mixing natural iron ore and oxidized iron ore to form a mixture, and heating or pre-reducing the mixture using a reaction gas to form a pre-heated or pre-reduced iron ore; an iron ore reduction furnace receiving the pre-heated or pre-reduced iron ore iron ore and reducing the pre-heated or pre-reduced iron ore using a reduction gas to form a reduced iron ore and produce the reaction gas; a molten gasification furnace receiving coal and the reduced iron ore and producing molten iron and the reduction gas; and an iron ore oxidizing-burning furnace receiving part of the reduced iron ore discharged from the iron ore reduction furnace and oxidizing the received reduced iron ore to produce the oxidized iron ore. The oxidized iron ore is supplied to the iron ore-mixing/pre-reducing furnace.

A process for the production of steel powders including the steps of: providing molten iron from a blast furnace, refining the molten iron in a converter to form molten steel including up to 600 ppm C, up to 120 ppm S, up to 125 ppm P, up to 50 ppm N and up to 1200 ppm O, pouring the molten steel in a plurality of induction furnaces, adding, in each of the plurality of induction furnaces, at least one ferroalloy to adjust the steel composition, pouring the molten steel at the desired composition of each induction furnace in a dedicated reservoir connected to at least one gas atomizer, feeding the at least one gas atomizer of each reservoir in molten steel from each reservoir under pressure and gas atomizing the molten steel to form the steel powder at the desired composition.