A method for producing direct reduced iron having increased carbon content, comprises: providing a carbon monoxide-rich gas stream, and separating the carbon monoxide-rich gas stream into at least two separate carbon monoxide-rich gas streams; providing a hydrocarbon-rich gas stream and separating the hydrocarbon-rich gas stream into at least two separate hydrocarbon-rich gas streams; blending one of the carbon monoxide-rich gas streams with one of the hydrocarbon-rich gas streams to form a mixed carburizing gas stream; blending another carbon monoxide-rich gas stream of the at least two separate carbon monoxide-rich gas streams with another hydrocarbon-rich gas stream of the at least two separate hydrocarbon-rich gas streams to form a distinct mixed carburizing gas stream; delivering each of the mixed carburizing gas streams, which are of different composition, to a transition zone of a direct reduction furnace, and exposing partially or completely reduced iron oxide to the mixed carburizing gas streams to increase the carbon content of resulting direct reduced iron to greater than 4.5 wt. %.

A direct reduction process comprises providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a direct reduced iron melting furnace; and coupling a discharge chute between a discharge exit of the direct reduced shaft furnace and an inlet of the direct reduced iron melting furnace; wherein direct reduced iron and the reducing gas from the shaft furnace flow through the discharge chute and the reducing gas controls the melting furnace atmosphere to reducing environment.

A plant complex for pig iron production may include a furnace and a furnace gas conduit system for a furnace gas quantity stream that comprises nitrogen, carbon monoxide, and carbon dioxide. The plant complex may also include a hydrogen source, an H.sub.2 gas conduit system for a hydrogen-containing gas quantity stream emitted from the hydrogen source, a mixing apparatus for establishing a mixed gas formed from the furnace gas stream and the hydrogen-containing gas quantity stream. The mixing apparatus may be connected to the furnace gas conduit system and to the H.sub.2 gas conduit system. The mixed gas established may have a stoichiometric mixing quotient formed from a dividend with a difference value between molar amounts of hydrogen as minuend and carbon dioxide as subtrahend and of a divisor with a sum value of molar amounts of carbon monoxide and carbon dioxide. The plant complex may also include a mixed gas conduit system and a chemical plant connected to the mixed gas conduit system.

A method and apparatus for producing direct reduced iron (DRI), including: generating a reducing gas in a coal gasifier using coal, oxygen, steam, and a first coke oven gas (COG) stream as inputs to the coal gasifier; and delivering the reducing gas to a shaft furnace and exposing iron ore agglomerates to the reducing gas to form metallic iron agglomerates. The method further includes delivering a second COG stream directly to the shaft furnace.

Smelting metalliferous feed material process forming molten metal in smelting apparatus including smelt cyclone above and communicating with smelting vessel to contain molten metal and slag bath, including: partially reducing and melting feed material in smelt cyclone, allowing the molten partially reduced feed material flow downwardly into vessel, supplying oxygen-containing gas and carbonaceous material to vessel, smelting molten partially reduced feed material in molten metal and slag bath in vessel forming molten metal discharged from vessel and reaction products projected upwardly from molten bath, at least partially combusting combustible materials in reaction products in vessel space above molten bath, supplying oxygen-containing gas to smelt cyclone. Further combusting reaction products in smelt cyclone, discharging from smelt cyclone offgas including reaction products, supplying oxygen-containing gas into offgas duct upstream high temperature section combusting remaining offgas combustible materials while sufficiently hot for safe ignition and avoiding downstream burner-managed incineration.

A method for the production of cast iron starting from pre-reduced iron ore (DRI) with an electric arc furnace includes the steps of preparing a charge of pre-reduced iron ore DRI having a metallization higher than 90% and containing over 2.8% by weight of carbon, wherein at least 80% of the carbon is combined with the iron to form iron carbide Fe.sub.3C; charging the charge of pre-reduced iron ore into the electric arc furnace; and melting the DRI charge to form liquid cast iron having at least 80% by weight of actual carbon content deriving from the carbon in the charge of pre-reduced iron ore, the melting step being in a reducing atmosphere and in a melting chamber of the electric arc furnace subjected to a positive internal pressure generated by the gases produced by reduction reactions that develop during melting.

A method for the recovery of zinc from zinc containing materials using a smelting apparatus for smelting a metalliferous feed material, wherein the smelting apparatus includes a smelting vessel, a smelt cyclone mounted on the smelting vessel and in connection with the inside of the smelting vessel and an off-gas duct connected to the smelt cyclone, and wherein the method includes the steps of: injecting the feed material with a carrier gas into the smelt cyclone, injecting an oxygen containing gas into the smelt cyclone, injecting coal with a carrier gas into the smelting vessel, injecting an oxygen containing gas into the smelting vessel, optionally injecting fluxes with a carrier gas into the smelting vessel, wherein the zinc containing materials are injected into the smelt cyclone and/or into the smelting vessel.

A method for recycling used cells such as saline cells, alkaline cells, button cells and used rechargeable batteries, includes the step of introducing the cells and/or rechargeable batteries as feedstock into a metal melting furnace, at the charging door thereof. The cells and/or rechargeable batteries are subjected to a compression operation in order to remove the electrolytes contained in the cells and/or rechargeable batteries, prior to introducing the cells and/or rechargeable batteries into the metal melting furnace.

The method can be used for recycling used cells and rechargeable batteries.

Producing direct reduced iron (DRI) having chemically-combined carbon includes providing DRI at a temperature above 400 C., providing a first gas stream including hydrogen and carbon monoxide, passing the first gas stream through a methane forming process to yield a second gas stream containing a higher concentration of methane than the first gas stream; and contacting the second gas stream with the DRI. A system for producing the DRI includes a vessel for containing DRI at a temperature above 400 C., a methane forming reactor containing a catalyst bed for producing methane from a first gas stream containing hydrogen and carbon monoxide, a first conduit to feed a gas stream including hydrogen and carbon monoxide to the methane forming reactor, and a second conduit to feed the second gas stream to the vessel containing the DRI.

A method and apparatus for producing direct reduced iron using a pre-treated make-up gas as a reducing agent in a direct reduced iron reactor are provided. The method involves pre-treating a stream of make-up gas containing heavy hydrocarbons by subjecting the stream to low temperature adiabatic reforming at a temperature between 300 C. and 600 C., prior to using the stream of make-up gas as a reducing agent for producing direct reduced iron. The method also involves adjusting the humidity content of the stream of make-up gas after the low temperature adiabatic reforming by bypassing the stream to selectively split it into a first part of the stream of make-up gas and a second part of the stream of make-up gas, subjecting the first part to water separation, and then mixing the first part with the second part to obtain a reducing stream to be sent to direct reduced iron production.