A method of producing pig iron in a shaft furnace is provided. The shaft furnace is charged in an upper region with raw materials which fall within the shaft furnace under the influence of gravity. A portion of the raw materials is melted and/or partly reduced under the action of the atmosphere that exists within the shaft furnace. A hot gas stream which is introduced in a lower region of the shaft furnace flows through and influences the atmosphere that exists within the shaft furnace in terms of chemical composition and temperature. A cold gas stream is fed to a heat exchanger in which the cold gas stream is heated to a temperature higher than 700 C. to give a hot gas stream. The cold gas stream comprises a CO.sub.2 component of at least 5% by volume. The cold gas stream may contain, air and/or pure oxygen as residual component.

Disclosed are methods useful in applications relating to blast furnace processes. The methods of the present invention provide enhanced deposition inhibition of particulate matter in top-pressure recovery turbines. The methods of the present invention comprise adding nitrogen-containing compounds to a top-pressure recovery turbine, inhibiting deposition of solids formed from blast furnace gas on top-pressure recovery turbine components.

The invention relates to a plant complex for steel production comprising a blast furnace for producing pig iron, a converter steel mill for producing crude steel and a gas-conducting system for gases that occur in the production of pig iron and/or in the production of crude steel. According to the invention, the plant complex additionally has a chemical or biotechnological plant connected to the gas-conducting system and a plant for producing hydrogen. The plant for producing hydrogen is connected to the gas-conducting system by a hydrogen-carrying line. Also the subject of the invention is a method for operating the plant complex.

A process for operating an oxidizable combustion gas cleaning unit in a metallurgical plant, including the steps of: (a) passing an oxidizable combustion gas from a metallurgical reactor, in particular a blast furnace gas from a blast furnace, in a packed bed scrubber arrangement through a packed bed in countercurrent with a washing water or in a spray scrubber arrangement to remove cyanide compounds, in particular hydrogen cyanide, and to increase the removal of chloride compounds, in particular hydrogen chloride, from the combustion gas by solubilizing the cyanide and chloride compounds in the washing water, (b) collecting the washing water containing solubilized cyanide and chloride compounds at a bottom end of the packed bed or spray scrubber arrangement, and (c) collecting a cleaned oxidizable combustion gas at a top of the packed bed or spray scrubber arrangement, wherein a base is added to the washing water before step (a).

The present blast furnace and method for operating a blast furnace are able to reduce CO.sub.2 production and the amount of applied additives and heating material. The method for metal production of metal ores comprising the following steps: reducing a metal ore, particularly a metal oxide, and thereby producing furnace gas containing CO.sub.2 in a blast furnace shaft; discharging the furnace gas from the blast furnace shaft; directing at least a portion of the furnace gas into a CO.sub.2 converter and reducing the CO.sub.2 in the furnace gas into CO; directing at least a portion of the CO from the CO.sub.2 converter into the blast furnace shaft. The method produces CO as a gaseous reduction agent which may be easily introduced into the blast furnace shaft. Further, a blast furnace for metal production by reducing a metal ore designed for operating according to the method is described.

A process and a device for treating a flow of furnace gas with a pressure of more than 1 bar flowing through a channel. A powder agent, such as a powder comprising alkali reagents, such as lime, and/or absorbents, such as activated coal, is injected under an overpressure into the furnace gas flow via an injector which is positioned centrally within the channel. The powder agent may be fluidized. The pressure for injecting the powder may be adjusted by controlling the volume of fluidization gas vented via a venting outlet.

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.

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.

A self-propelled slag transporter, The self-propelled slag transporter includes a drive, a chassis, a lifting device with at least one lifting drive and a receiving device for receiving a metallurgical transport container, in particular a slag container, wherein the receiving device is designed to be height-adjustable by the lifting device, and wherein the chassis has at least two crawler tracks.

A method for operating a blast furnace includes blowing pulverized coal and oxygen from an upstream lance configured by a double tube. LNG is blown from a downstream lance on the downstream side in a hot air blast direction, oxygen is supplied from the upstream lance, 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. With respect to a direction perpendicular to the hot air blast and a downstream direction of the hot air blast, a blowing direction of the LNG from the downstream lance with respect to the blast direction ranges from 30 to +45. A blast pipe circumferential direction angle at a blowing position of the LNG from the downstream lance with respect to where the upstream lance is inserted into a blast pipe ranges from 160 to 200.