The present disclosure relates to systems and methods for the production of molten metals direct oxidative combustion of one or more solid fuels. The systems and methods may be combined with coal gasifiers and related components for reducing overall energy requirements as well as external fuel sources, e.g., through the use of endogenously-generated hydrogen. In beneficial aspects, components of the carbonaceous exhaust produced in accordance with the disclosed systems and methods, such as carbon dioxide (CO.sub.2), may be isolated using carbon capture and sequestration (CCS) for reducing associated greenhouse gas emissions.

Disclosed herein, in some aspects, are systems and methods for producing a material comprising iron through self-reduction of iron ore using bio-oil and/or other reducing agents (e.g., bio-based reducing agents), such as biocrude, ethanol, or other bio-based liquids or biologically sourced liquids. The bio-oil and/or other reducing agents can be mixed with the iron ore to form a furnace mixture, which can be heated, such that the components of the bio-oil and/or other reducing agents in the furnace mixture reduce the iron ore to form an iron product (e.g., a material that includes metallic iron). In some cases, the pre-formed furnace mixture allows for the reducing agents to interact with the iron more readily, thereby providing for quicker reaction rates, and thereby quicker reduction of iron ore, as compared to direct reduction iron production.

In a method and a device for operating a smelting reduction process, at least part of an export gas from a blast furnace or a reduction unit is thermally utilized in a gas turbine and the exhaust gas of this gas turbine is used in a waste heat steam generator to generate steam. The remaining part of the export gas is fed to a CO.sub.2 separation apparatus, the tail gas thereby obtained being fed to a waste heat steam generator and burned for additional steam generation. The combustible components of the tail gas are sent for thermal utilization in a steam generator, so that the overall energy balance of the thermal use of the export gas is improved. In addition, a further part of the export gas is qualitatively improved by the CO.sub.2 separation apparatus, so as to generate a high-quality reduction gas which can be supplied for metallurgical use.

Included are: a direct reduction furnace for reducing iron ore directly into reduced iron using a high-temperature reducing gas including hydrogen and carbon monoxide, an acid gas removal unit having an acid gas component absorber for removing, with an absorbent such as an amine-based solvent, acid gas components (CO.sub.2, H.sub.2S) in a reduction furnace flue gas discharged from the direct reduction furnace, and a regenerator for releasing the acid gas, and a degradation product removal unit for separating and removing a degradation product in the absorbent used by circulating through the absorber and the regenerator.

A method of starting a molten-bath based melting process includes commencing supplying cold oxygen-containing gas and cold carbonaceous material into a main chamber of a smelting vessel within at most 3 hours after completing a hot metal charge into the vessel and igniting the carbonaceous material and heating the main chamber and molten metal in the main chamber.

A process for processing metal ore includes: reducing a metal ore, particularly a metallic oxide, in a blast furnace shaft; producing furnace gas containing CO.sub.2, in the blast furnace shaft; discharging the furnace gas from the blast furnace shaft; directing at least a portion of the furnace gas directly or indirectly into a CO.sub.2-converter; and converting the CO.sub.2 contained in the furnace gas into an aerosol consisting of a carrier gas and C-particles in the CO.sub.2-converter in the presence of a stoichiometric surplus of C; directing at least a first portion of the aerosol from the CO.sub.2-converter into the blast furnace shaft; and introducing H.sub.2O into the blast furnace shaft. By virtue of the reaction C+H.sub.2O.fwdarw.CO.sub.2+2H, nascent hydrogen is produced in the blast furnace which causes rapid reduction of the metal ore. The speed of reduction of the metal ore is thus increased, and it is possible to increase either the throughput capacity of the blast furnace or to reduce the size of the blast furnace. An aerosol in the form of a fluid is easily introducible into the blast furnace shaft.

Method of operating a blast furnace installation comprising a top gas recycle blast furnace and hot stones, whereby a hydrocarbon containing fuel is transformed into a transformed gas stream consisting mainly of CO and H.sub.2 and substantially devoid of hydrocarbon, whereby a low-heating-value gaseous fuel is generated comprising a mixture of said transformed gas with a portion of the CO.sub.2-rich tail gas obtained by decarbonatation of the blast furnace gas, and whereby said low-heating-value fuel is used to heat the hot furnace gas is heated before being injected into the blast-furnace.

A system for energy optimization in a plant (3) for producing direct-reduced metal ores (3). The plant (3) has at least one reduction unit (12), a device for separating gas mixtures (7, 7a, 7b) having an associated compressing device (4, 4a, 4b), and a gas-heating device (10) upstream of the reduction unit (12). Part of the process gases (2, 2a, 2b) is fed by a feed line from a smelting reduction plant to the plant for producing direct-reduced metal ores (3). A turbine (8, 8a, 8b) is fit between the device for separating gas mixtures (7, 7a, 7b) and the gas-heating device (10) upstream of the reduction unit (12) such that a pressure drop between the device for separating gas mixtures (7, 7a, 7b) and the reduction unit (12) is converted into forms of energy that can be used to operate additional components (4, 4a, 4b, 15, 15a, 15b) of the plant (3), in particular electrical energy and/or mechanical energy. Energy consumption of the plant (3) is reduced.

When CO.sub.2 is removed from a blast furnace gas containing unused CO gas and CO gas after removing CO.sub.2 is again injected into a blast furnace, nitrogen accumulates in the blast furnace. O.sub.2 is thus injected instead of blast. This causes the absence of nitrogen in front of a tuyere, so that a volume of gas generated in front of the tuyere is insufficient and a temperature in front of the tuyere rises, resulting in a difficulty in the blast furnace operation. N.sub.2 gas or CO.sub.2 gas is thus injected together with the CO gas injected through the tuyere, and circulated.

The present disclosure relates to systems and methods for the production of molten metals direct oxidative combustion of one or more solid fuels. The systems and methods may be combined with coal gasifiers and related components for reducing overall energy requirements as well as external fuel sources, e.g., through the use of endogenously-generated hydrogen. In beneficial aspects, components of the carbonaceous exhaust produced in accordance with the disclosed systems and methods, such as carbon dioxide (CO.sub.2), may be isolated using carbon capture and sequestration (CCS) for reducing associated greenhouse gas emissions.