The present disclosure provides a facility to produce direct reduced iron, which makes it possible to perform reforming and reduction and adjust the carbon amount in a product within a wide range without requiring an externally heating reformer and without causing the metal dusting problem in a circulating gas preheater and the problem of sintering each other or fusion between reduced iron, in a furnace. The facility to produce the direct reduced iron according to the present invention is equipped with a water content control device for controlling the water content in a gas discharged from a shaft-type reduction furnace, a first gas mixing device for mixing the gas from which a portion of water has been removed with an oxygen-containing gas and a hydrocarbon-containing gas to produce a mixed gas, and an auto-thermal reformer for reforming the mixed gas with its energy. The facility is also equipped with a cooling gas loop for circulating a cooling gas, wherein the cooling gas has a hydrocarbon concentration of 50% or more, and the cooling gas loop is equipped with a cooling gas after-cooler having a flow rate control function and capable of controlling the temperature of the cooling gas.

An apparatus for direct reduction of iron ore in a solid state including a pre-heating furnace for pre-heating iron ore fragments and biomass in briquettes of these materials to a temperature in the range of 400-900° C.; and a reduction assembly for briquettes from the pre-heating furnace. The reduction assembly includes a reaction chamber, a source of electromagnetic energy in the form of microwave energy, a wave guide for transferring microwave energy to the chamber for heating and reducing iron ore in briquettes from the pre-heating furnace, with biomass acting as a reductant, a source of an inert gas, pipework for supplying the inert gas to the chamber to maintain the chamber under anoxic conditions, and an outlet for discharging an offgas and any retained particulates that are generated in the chamber.

A CO.sub.2 separation/recover method in cement production exhaust gas has a step of harmful component removal that removes an acidic component and a harmful component from exhaust gas discharged from a cement production facility; and a step of CO.sub.2 separation and recover that separates and recovers CO.sub.2 by bringing the exhaust gas from which the acidic component and the harmful component are removed into contact with a CO.sub.2 absorption material, so that the acidic component and the harmful component are removed before separating and recovering CO.sub.2, resulting in deterioration of the absorbing ability of the CO.sub.2 absorption material being suppressed; and the cement production exhaust gas can be appropriately disposed.

Generating methane by adding hydrogen to CO.sub.2 in exhaust gas discharged a from cement production facility or CO.sub.2 that is separated and recovered from the exhaust gas, and using the methane as an alternative fuel to fossil fuel such as coal, petroleum, natural gas and the like, by methanation of CO.sub.2 in the exhaust gas from the cement production facility that includes exhaust gas originated from lime stone not from the fossil oil and effectively utilizing it, it is possible to reduce usage of the fossil fuel, suppress CO.sub.2 originated from energy, and improve an effect of reducing greenhouse gas.

A plant complex may include a unit that produces CO.sub.2-containing gases, a gas conducting system for CO.sub.2-containing gases, a gas/liquid separation system, a reformer that is connected to the gas conducting system and where the CO.sub.2-containing gas reacts with H.sub.2 and/or hydrocarbons to give a CO— and H.sub.2-containing synthesis gas mixture. The reformer is connected to a reactor for producing higher alcohols in which the synthesis gas mixture reacts with H.sub.2 to give a gas/liquid mixture containing higher alcohols. For separating off the alcohols of the gas/liquid mixture, the gas/liquid separation system is connected to the reactor for producing higher alcohols.

A method for producing a homogenous molten composition and a fluid product is disclosed. For example, the method includes producing a first molten metal composition in an enclosed volume, contacting a hydrocarbon reactant with the first molten metal composition, decomposing the hydrocarbon reactant into at least one fluid product and carbon, forming a metal alloy from a mixture of the carbon and the first molten metal composition, and separating a homogenous second molten composition from the metal alloy.

A full-fiber burner brick and a preparation method thereof, comprising mixing alumina crystal fiber and amorphous ceramic fiber with both of them being a combination of fibers of different lengths gradations, and moreover adding fine powder fillers of different particle size gradations and supplementing other additives. This enables the internal structure of the product more uniform, increases the bulk density of the product, and also benefits the suction filterability of fiber cotton blank, and is conducive to forming and improving the strength of the blank. The surface of the brick body is further provided with a coating, which can effectively protect the cotton fiber of the brick body fiber from harsh environments, improve its high temperature resistance, and help to extend the service life of the burner brick.

Disclosed herein are methods and compositions for producing composite pellets comprising a core comprising: iron ore and a carbonaceous reducing agent; and a shell comprising: iron ore; and having a core and shell transition in a manner such that no visible boundary exists between the core and the shell in a cross-section of the pellet. The methods can be used to produce composite pellets with improved productivity and quality, and the resulting composite pellets can be used to produce direct reduced iron (DRI).

In a method for producing a molten steel according to one aspect of the present invention, the solid-state direct reduced iron contains 3.0% by mass or more of SiO.sub.2 and Al.sub.2O.sub.3 in total and 1.0% by mass or more of carbon. A ratio of a metallic iron to the total iron content contained in the solid-state direct reduced iron is 90% by mass or more, and an excess carbon content Cx is 0.2% by mass or more to the carbons contained in the solid-state direct reduced iron. The method includes a step in a first furnace of melting 40 to 100% by mass of the solid-state direct reduced iron, and separating a molten pig iron having a carbon content of 2.0 to 5.0% by mass and a temperature of 1350 to 1550° C. and a slag having a basicity of 1.0 to 1.4 and a step in a second furnace of melting a remainder of the solid reduced iron together with the molten pig iron separated in the first furnace and blowing oxygen onto the molten material to decarburize into a molten steel.

Provided is a method of operating a blast furnace, having generating a regenerative methane gas from a by-product gas discharged from the blast furnace, and blowing a blast gas and a reducing agent into the blast furnace from a tuyere of the blast furnace in which the blast gas is oxygen gas and the regenerative methane gas is used as at least part of the reducing agent.