Method for producing reduced iron

A method for producing reduced iron, the method comprising

• agglomerating small agglomerates of particle sizes of 10 mm or less containing a carbonaceous reducing agent and an iron oxide-containing material;
• charging the small agglomerates onto a hearth of a reduction furnace so as to form a number of layers of the small agglomerates obtained from an operation condition;
• heating the small agglomerates within the reduction furnace;
• and
• solid reducing iron oxide in the small agglomerates to produce solid reduced iron, wherein
• the operation condition is given by the following expression:
• H=Z {X(G/P)}/{A(AD)(π/6)(D/T)}
• where
• H is the number of layers of the small agglomerates on the hearth,
• Z is a positive number ranging from 0.7 to 1.3,
• X is a productivity (kg/min) of the reduction furnace,
• G/P is a mass ratio of the small agglomerates charged onto the hearth to the solid reduced iron produced,
• A is an area (m2) of the hearth on which the small agglomerates are charged,
• AD is an apparent density (kg/m3) of the small agglomerates,
• D is a particle size of the small agglomerates (m), and
• T is a production time (min).

A method for producing reduced iron, the method comprising

• agglomerating a raw material mixture containing a carbonaceous reducing agent and an iron oxide-containing material;
• heating the agglomerate within a heating reduction furnace;
• and
• solid reducing iron oxide in the agglomerate to produce solid reduced iron, wherein
• the agglomerate of the raw material mixture has a particle size in a range of from 3 mm to less than 6 mm.

A method for producing granular metallic iron, the method comprising.

• agglomerating a raw material mixture containing a carbonaceous reducing agent and an iron oxide-containing material into small agglomerates;
• heating the small agglomerates in a reduction melting furnace to solid reduce iron oxide in the small agglomerates;
• melting metallic iron produced by the reduction;
• and
• coagulating the molten metallic iron while separating a slag component contained in the small agglomerates to provide granular metallic iron, wherein
• 60 mass % or more of the small agglomerates have a particle size in a range of from 3 mm to less than 6 mm.