Proposed is a system for carbon dioxide capture and carbon recycling for a steel mill. The system includes a fluidized bed reduction furnace configured to reduce fine iron ore to reduced iron by using a reducing gas, a first discharge means configured to discharge an exhaust gas generated from the fluidized bed reduction furnace, a melting furnace configured to manufacture molten iron, a second discharge means configured to discharge an exhaust gas generated from the melting furnace, and a reactor configured such that when the reactor receives the exhaust gas discharged from the fluidized bed reduction furnace and the melting furnace as the reducing gas, the reactor captures carbon dioxide in the reducing gas by reacting the reducing gas with a basic alkaline mixture solution, and then collects a reactant and injects, into the fluidized bed reduction furnace, the reducing gas from which carbon dioxide is removed.

Provided is a method of operating a blast furnace, including generating a regenerative methane gas using a blast furnace by-product gas, and blowing a blast gas and a reducing agent into the blast furnace from a tuyere, in which the blast gas is oxygen gas, the regenerative methane gas is used as at least part of the reducing agent, and the oxygen gas and/or the regenerative methane gas is preheated before being blown into the blast furnace from the tuyere.

The present disclosure provides systems and methods for iron production as well as apparatuses useful in such systems and methods. Metallic iron is produced in a DRI furnace into which is introduced raw iron (iron oxides) and a syngas. The syngas is formed using a first processing unit, such as a CO.sub.2 convective reformer (CCR), and optionally a second processing unit, such as an oxygen secondary reformer (OSR), to react a hydrocarbon with a reformant to form syngas with substantially complete carbon capture. Top gas from the DRI furnace may be used in a combustor as a fuel to form a heated exhaust stream that is used to provide reaction heating to the first processing unit, and the exhaust stream received from the first processing unit may be further processed so that at least a portion of the exhaust stream may be recycled to the combustor.

A process for producing solid carbon and gaseous oxygen from CO.sub.2 via electrolysis using an electrolysis apparatus is disclosed. The apparatus includes a chamber with an electrolyte inlet, an electrolyte outlet, a liquid electrolyte containing CO.sub.2 in the chamber, at least one cathode-anode pair, with the cathode including a liquid metal capable of catalysing reduction of CO.sub.2 to solid carbon at a selected operating temperature of the process. The process includes causing the electrolyte to flow from the inlet to the outlet in fluid communication with the cathode-anode pair, applying a voltage between the cathode-anode pair and causing solid carbon to form on the cathode from CO.sub.2 in the electrolyte and gaseous oxygen to be evolved at the anode from CO.sub.2 in the electrolyte.

The present invention provides a reduction system and method that can be operated with any proportion of gaseous hydrogen-containing gases and gaseous hydrocarbon-containing gases having the possibility of continuing its operation, ensuring an high process availability and negligible loss of production, when the gaseous hydrogen-containing gas for any reason is not available and allow the substitution of the gaseous hydrogen-containing gas with a gaseous hydrocarbon-containing gas with minor adjustments in the plant operation. The reduction system of the invention is designed to be implemented in new and already built direct reduction plants to operate efficiently and has lower capital and operation costs.

System and method for producing steel is provided that efficiently reduce carbon dioxide emissions. A steel production system includes: a first gas generating section configured to obtain a first gas by converting carbon monoxide, to carbon dioxide, in a gas containing the carbon dioxide and carbon monoxide; a reducing gas supply section 3 configured to supply a reducing gas containing a reducing substance to reduce a reducing agent, the reducing agent containing metal oxide to reduce carbon dioxide and being oxidized by contact with the carbon dioxide; and a reaction section 4 including a plurality of reactors 4a and 4b, respectively connected to at least one of the first gas generating section and the reducing gas supply section 3, and the reducing agent arranged in the reactors 4a and 4b, the reaction section being capable of switching between the first gas and the reducing gas to be supplied to each of the reactors 4a and 4b, wherein a second gas is configured to be supplied to a blast furnace, the second gas being obtained by contacting the first gas supplied to the reactors 4a and 4b with the reducing agent to convert the carbon dioxide to carbon monoxide and the second gas having the carbon monoxide as a main component.

Provided is a solid carbon production facility including: a separation facility configured to separate a carbon dioxide gas contained in a produced gas produced by a blast furnace; a reaction facility configured to heat a fuel gas whose main component is a methane gas by using a heating facility and decompose the methane gas into solid carbon and a hydrogen gas; and a production facility configured to cause the carbon dioxide gas separated by the separation facility and the hydrogen gas decomposed by the reaction facility to react with each other to produce solid carbon and water.

A method for producing molten iron. The reduction of iron oxide-containing material to form a metallized product is performed using a reduction gas consisting at least largely of hydrogen H2. Top gas is accumulated during the reduction process. First sub-quantity of top gas is combined with reducing reduction gas components to provide reduction gas, and second sub-quantity of the top gas, as a discharged gas, is subjected to a gas separation process into a hydrogen-enriched gas flow and a hydrogen-depleted tail gas flow. Metallized product of the reduction process is combined with carbon carriers to be melted in a melting device to form a molten iron, and a smelting exhaust gas is accumulated. Sub-quantity of the tail gas flow is combined with at least a sub-quantity of the smelting exhaust gas, and a tail gas mixture is produced. Sub-quantity of the tail gas mixture is supplied to a thermal use.

In various examples, the subject matter of this disclosure relates to a method and a system for producing metallic iron. An example method includes: obtaining bio-oil; obtaining iron ore fines; providing the bio-oil to a gasifier to produce syngas from the bio-oil, the syngas including tar and/or particulate; and providing the syngas and the iron ore fines to a fluidized bed reactor where iron oxide in the iron ore fines is at least partially reduced using the syngas.

A gas production apparatus includes: a separator configured to separate and capture a separated gas including carbon dioxide as a main component from an exhaust gas of exhaust gas equipment; reactors which are downstream of the separator, each of the reactors: (i) containing a reductant configured to contact the separated gas to produce carbon monoxide through a reduction reaction of carbon dioxide; (ii) being configured to separate at least some oxygen atoms split off from carbon dioxide in the reduction reaction; and (iii) having a reducing agent containing a metal oxide configured to reduce carbon dioxide as the reductant; a reducer configured to supply a reducing gas containing a reducing substance configured to reduce the reducing agent oxidized by contact with carbon dioxide; a pressure regulator configured to regulate a pressure of the separated gas; and a flow regulator configured to regulate a flow rate of the separated gas.