A high-efficiency method for producing metal from metal oxide by carbothermic reduction includes step in which a holed cake is provided, which has a composition comprising a metal oxide, a carbonaceous reducing agent, and a binder, and the holed cake has a plurality of holes. The method continues with step in which the holed cake is placed in a high-temperature furnace for carbothermic reduction, to reduce the metal oxide in the holed cake into a metal.

A metal agglomerate production configuration including an induration apparatus configured to provide a metal oxide material manufacturing thermal process (MTE) including indurating a metal ore material into a metal oxide material and a method of production of metal agglomerates. A cooler device is configured for cooling the metal oxide material discharged from the induration apparatus and includes a first heat transferring arrangement configured for transferring a first heat energy content (HE) to the induration apparatus, which first heat energy content (HE) is recovered from the metal oxide material holding the thermal energy (TE). The configuration includes a second heat transferring arrangement configured for transferring a second heat energy content (HE) from the induration apparatus to the cooler device for cooling of the metal oxide material, which second heat energy content (HE) is recovered from the metal oxide material manufacturing thermal process (MTE).

The present disclosure provides a pre-reduced pellet preparation device and method based on grate-rotary kiln. The pre-reduced pellet preparation device comprises a grate-rotary kiln pellet oxidation system and a hydrogen-based shaft furnace reduction system. In the pre-reduced pellet preparation method, a roasting process and a reduction process for an iron-containing green pellet are organically combined, and a pellet cooling process after roasting and a heating process before pellet reduction are eliminated; physical heat of a roasted pellet is used to satisfy heat required in the heating and reduction processes; the technical problems of a low hydrogen utilization rate and high energy consumption of pellets in oxidative roasting and direct reduction processes in traditional direct reduction processes are solved; a reduced pellet having a certain metallization rate is obtained; the prepared pre-reduced pellet is used as blast furnace burden, such that blast furnace fuel consumption and carbon emission can be significantly reduced; the method is a new, low-carbon, and green pre-reduced pellet preparation process.

The reduced iron manufacturing method of the present invention includes preparing an agglomerate by agglomerating a mixture containing an iron oxide-containing substance and a carbonaceous reducing agent, and preparing reduced iron by heating the agglomerate to reduce iron oxide in the agglomerate, characterized in that Expression (I) as follows is satisfied:

C.sub.fix?X.sub.under105/O.sub.FeO?51(I)

where O.sub.FeO is the mass percentage of oxygen contained in the iron oxide in the agglomerate, C.sub.fix is the mass percentage of total fixed carbon contained in the agglomerate, and X.sub.under105 is the mass percentage of particles having a particle diameter of 105 ?m or less with respect to the total mass of particles configuring the carbonaceous reducing agent.

This method is for producing granular metallic iron in which the relation between the mass ratio (mass %) of the volatile matter content contained in a carbonaceous reducing agent and the average gas flow rate (m/s) of the ambient gas in a heating furnace fulfills expression (1). Mass ratio of volatile matter content4.62average gas flow rate+46.7 . . . (1)