The present invention pertains to metallurgical processes and equipment and, more particularly, to a metallurgical furnace capable of operating with a broad range of broad range of raw materials and fuels, including those with high levels of impurities. Accordingly, the metallurgical furnace of the present invention comprises (i) at least an upper tub, (ii) at least a lower tub, (iii) at least a fuel feeder positioned substantially between the at least an upper tub and the at least a lower tub, (iv) at least a row of tuyeres positioned on at least one of at least an upper tub and at least a lower tub, the at least a row of tuyeres fluidly communicating inside the furnace with the outside environment, and (v) at least a burner positioned on at least one of at least an upper tub and at least a lower tub. The use of at least a burner jointly with the at least a row of tuyeres generates a very intense release of heat by virtue of the exothermic reactions which occur by this combination.

A cupola furnace includes at least one tuyere opening into an interior of the cupola; and at least one oxygen stream and at least one natural gas (NG) stream in fluid communication with said at least one tuyere for providing oxygen and NG to the cupola furnace interior. A related method is also provided for heating a cupola furnace, and includes introducing at least one oxygen stream and at least one NG stream into the cupola furnace for reaction therein.

A cupola furnace includes at least one tuyere opening into an interior of the cupola; and at least one oxygen stream and at least one natural gas (NG) stream in fluid communication with said at least one tuyere for providing oxygen and NG to the cupola furnace interior. A related method is also provided for heating a cupola furnace, and includes introducing at least one oxygen stream and at least one NG stream into the cupola furnace for reaction therein.

A process for producing DRI from iron ores, utilizing a gas produced from fossil fuels, containing sulfur compounds and BTX, heating said gas in a heater, preferably a regenerator, wherein heat is transferred from a previously-heated solid material to the gas. Flowing the hot gas through a bed of DRI particles, iron oxides or other equivalent material, outside of the reduction reactor, where said material adsorbs sulfur compounds and destroys BTX. The resulting gas, free from sulfur compounds and BTX, is combined with a reducing gas stream from the reduction reactor after H.sub.2O and CO.sub.2 is at least partially removed for regenerating its reducing potential, with or without undergoing previous cleaning, is used for producing DRI. One inventive embodiment comprises producing DRI at high temperature giving advantageously higher productivity and energy savings when using hot DRI in an electric arc furnace lowering the capital and operational costs of steelmaking.

A process for producing DRI from iron ores, utilizing a gas produced from fossil fuels, containing sulfur compounds and BTX, heating said gas in a heater, preferably a regenerator, wherein heat is transferred from a previously-heated solid material to the gas. Flowing the hot gas through a bed of DRI particles, iron oxides or other equivalent material, outside of the reduction reactor, where said material adsorbs sulfur compounds and destroys BTX. The resulting gas, free from sulfur compounds and BTX, is combined with a reducing gas stream from the reduction reactor after H.sub.2O and CO.sub.2 is at least partially removed for regenerating its reducing potential, with or without undergoing previous cleaning, is used for producing DRI. One inventive embodiment comprises producing DRI at high temperature giving advantageously higher productivity and energy savings when using hot DRI in an electric arc furnace lowering the capital and operational costs of steelmaking.

A method for producing molten pig iron includes a first step of producing carbon-material-containing agglomerated ore from an iron-containing and carbon-containing raw materials, a second step of blowing an oxygen-containing gas into the carbon-material-containing agglomerated ore to reduce and melt it, thereby producing molten pig iron, and a third step of bringing a carbon-containing gas containing carbon monoxide and carbon dioxide produced as a by-product of the reduction into contact with a porous material, thereby recovering carbon, in which in the first step, the carbon recovered in the third step is used for a part of or an entirety of the carbon-containing raw material. The method may include, instead of the second step, a reduction step of heating the carbon-material-containing agglomerated ore to 1160 to 1450 C., and then cooling the carbon-material-containing agglomerated ore to obtain reduced iron, and a step of melting the reduced iron to produce molten pig iron.

A method for producing molten pig iron includes a first step of producing carbon-material-containing agglomerated ore from an iron-containing and carbon-containing raw materials, a second step of blowing an oxygen-containing gas into the carbon-material-containing agglomerated ore to reduce and melt it, thereby producing molten pig iron, and a third step of bringing a carbon-containing gas containing carbon monoxide and carbon dioxide produced as a by-product of the reduction into contact with a porous material, thereby recovering carbon, in which in the first step, the carbon recovered in the third step is used for a part of or an entirety of the carbon-containing raw material. The method may include, instead of the second step, a reduction step of heating the carbon-material-containing agglomerated ore to 1160 to 1450 C., and then cooling the carbon-material-containing agglomerated ore to obtain reduced iron, and a step of melting the reduced iron to produce molten pig iron.

The invention relates to a process for producing low-nitrogen crude steel. This process includes melting directly reduced iron and/or scrap in a melting furnace with arc resistance heating to give a metallic melt and a slag. The metallic melt is removed from the melting furnace and used to charge a converter. The metallic melt is refined in the converter to give liquid crude steel. The liquid crude steel is tapped having a nitrogen content [N] of not more than 50 ppm, especially of not more than 30 ppm.

The invention relates to a process for producing low-nitrogen crude steel. This process includes melting directly reduced iron and/or scrap in a melting furnace with arc resistance heating to give a metallic melt and a slag. The metallic melt is removed from the melting furnace and used to charge a converter. The metallic melt is refined in the converter to give liquid crude steel. The liquid crude steel is tapped having a nitrogen content [N] of not more than 50 ppm, especially of not more than 30 ppm.