A method for burning material, such as carbonate rocks, in a parallel-flow regenerative shaft kiln having two shafts which are operated alternately as a burning shaft and as a regenerative shaft and are connected to one another by means of a connecting channel, wherein the material flows through a material inlet into a preheating zone for preheating the material, a burning zone for burning the material and a cooling zone for cooling the material to a material outlet, wherein a cooling gas is admitted into the cooling zone, wherein exhaust gas is discharged from one of the shafts via an exhaust gas outlet, wherein the exhaust gas discharged from the shaft via the exhaust gas outlet is at least partially introduced into at least one of the shafts.

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.

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 method is provided for operating a blast furnace by blowing a solid reducing material, a flammable gaseous reducing material and a combustible gas into a blast furnace from tuyeres through a lance into a blast furnace, wherein a parallel type lance prepared by bundling three independent blowing tubes in parallel and integrally housing them into an outer tube is used, and either one or both of the gaseous reducing material and the combustible gas and the solid reducing material are simultaneously blown through the respective blowing tubes, while the blowing tube for the solid reducing material and the blowing tube for the gaseous reducing material are positioned above the blowing tube for the combustible gas in the blowing through the parallel type lance as well as a lance structure thereof.

A method is provided for operating a blast furnace by blowing a solid reducing material, a flammable gaseous reducing material and a combustible gas into a blast furnace from tuyeres through a lance into a blast furnace, wherein a parallel type lance prepared by bundling three independent blowing tubes in parallel and integrally housing them into an outer tube is used, and either one or both of the gaseous reducing material and the combustible gas and the solid reducing material are simultaneously blown through the respective blowing tubes, while the blowing tube for the solid reducing material and the blowing tube for the gaseous reducing material are positioned above the blowing tube for the combustible gas in the blowing through the parallel type lance as well as a lance structure thereof.

A method is provided for operating a blast furnace by blowing at least a solid reducing material and a combustible gas into the furnace through tuyeres with a lance inserted into a blowpipe, wherein a tube-bundle type lance obtained by bundling a plurality of blowing tubes is used and when only a solid reducing material or two kinds of a solid reducing material and a combustible gas or three kinds of a solid reducing material, a combustible gas and a gaseous reducing material is simultaneously blown into an inside of the blast furnace through a tube for blowing the solid reducing material, a tube for blowing the combustible gas and a tube for blowing the gaseous reducing material in the tube-bundle type lance, two or more tube-bundle type lances are inserted into the blowpipe to approximate their front ends to each other and blowing is performed so that the respective blowout streams interfere with each other in the blowpipe.

A method is provided for operating a blast furnace by blowing at least a solid reducing material and a combustible gas into the furnace through tuyeres with a lance inserted into a blowpipe, wherein a tube-bundle type lance obtained by bundling a plurality of blowing tubes is used and when only a solid reducing material or two kinds of a solid reducing material and a combustible gas or three kinds of a solid reducing material, a combustible gas and a gaseous reducing material is simultaneously blown into an inside of the blast furnace through a tube for blowing the solid reducing material, a tube for blowing the combustible gas and a tube for blowing the gaseous reducing material in the tube-bundle type lance, two or more tube-bundle type lances are inserted into the blowpipe to approximate their front ends to each other and blowing is performed so that the respective blowout streams interfere with each other in the blowpipe.

To provide a method for operating a blast furnace with which the combustion efficiency of a solid fuel, such as pulverized coal, is improved, thereby making it possible to improve productivity and reduce CO.sub.2 emissions. Pulverized coal and LNG are blown from an upstream lance configured by a double tube, and oxygen is blown from a downstream lance on the downstream side in a hot air blast direction, so that oxygen used for preceding combustion of the LNG is supplied from the downstream lance, and the pulverized coal whose temperature has been increased by the combustion of the LNG is combusted along with the supplied oxygen. When a direction perpendicular to the hot air blast direction is designated as 0 , and a downstream direction and an upstream direction therefrom in the hot air blast direction are designated as positive and negative, respectively, a blowing direction of the oxygen from the downstream lance with respect to the blast direction ranges from 30 to +45 , and a blowing position of the oxygen from the downstream lance with reference to a position at which the upstream lance is inserted into a blast pipe ranges from 160 to 200 in terms of a blast pipe circumferential direction angle.

To provide a method for operating a blast furnace with which the combustion efficiency of a solid fuel, such as pulverized coal, is improved, thereby making it possible to improve productivity and reduce CO.sub.2 emissions. Pulverized coal and LNG are blown from an upstream lance configured by a double tube, and oxygen is blown from a downstream lance on the downstream side in a hot air blast direction, so that oxygen used for preceding combustion of the LNG is supplied from the downstream lance, and the pulverized coal whose temperature has been increased by the combustion of the LNG is combusted along with the supplied oxygen. When a direction perpendicular to the hot air blast direction is designated as 0 , and a downstream direction and an upstream direction therefrom in the hot air blast direction are designated as positive and negative, respectively, a blowing direction of the oxygen from the downstream lance with respect to the blast direction ranges from 30 to +45 , and a blowing position of the oxygen from the downstream lance with reference to a position at which the upstream lance is inserted into a blast pipe ranges from 160 to 200 in terms of a blast pipe circumferential direction angle.

To provide a method for operating a blast furnace with which the combustion efficiency of a solid fuel, such as pulverized coal, is improved, thereby making it possible to improve productivity and reduce CO.sub.2 emissions. Pulverized coal and oxygen are blown from an upstream lance 4 configured by a double tube, and LNG is blown from a downstream lance 6 on the downstream side in a hot air blast direction, so that oxygen to be used for combustion of the LNG is supplied from the upstream lance 4, and the pulverized coal whose temperature has been increased by the combustion of the LNG is combusted along with the supplied oxygen or oxygen in an air blast. When a direction perpendicular to the hot air blast direction is designated as 0, and a downstream direction and an upstream direction therefrom in the hot air blast direction are designated as positive and negative, respectively, a blowing direction of the LNG from the downstream lance 6 with respect to the blast direction ranges from 30 to +45, and a blowing position of the LNG from the downstream lance 6 with reference to a position at which the upstream lance 4 is inserted into a blast pipe 2 ranges from 160 to 200 in terms of a blast pipe circumferential direction angle.