The present invention relates to an ironmaking feedstock comprising a solid CaFe.sub.3O.sub.5 phase. The ironmaking feedstock may be produced by a process comprising reacting a combination of a calcium source and magnetite at elevated temperature under reducing conditions sufficient to produce the solid CaFe.sub.3O.sub.5 phase. The product may be in the form of agglomerates such as pellets, with a compressive strength such that the product is suitable for transportation.

A method for measuring the softening and melting performances of iron ore in blast furnace is disclosed, which is implemented by a device including a high temperature furnace, gas supply system, a loading system and a weighing system. The method includes: step 1: the dried coke and iron ore specimen are placed in the graphite crucible in a specified way; step 2: the graphite crucible is placed in the high temperature furnace, and N.sub.2 is continuously fed into the high temperature furnace to reach an airtightness requirement; step 3: a vacuum pump is used to extract mixed gas in a hearth of the high temperature furnace and heating process is started; step 4: both the composition of mixed gas and pressure imposed on the iron ore are controlled according to the designed temperature variation; step 5: data are acquired to calculate.

The use of pellets comprising one or more thermoplastic material(s) of more than 40%, based on the total dry weight of the pellets and one or more cellulosic material(s) of more than 20%, based on the total dry weight of the pellets, as a reducing agent in a process for making pig iron in a blast furnace. The pellets can be provided in unground form, as a partial replacement of coke through the top of the blast furnace, or can be provided as reducing agent in the raceway in an amount of higher than 10 kg/ton iron.

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.

In a ferrocoke manufacturing method by shaping and carbonizing a mixture of coal and iron ore, a hardly softening coal having a button index (CSN) of not more than 2.0 is used as the coal. The coal can be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.0 and a volatile matter of not less than 17%, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is a range of 0.3-5.2. The coal can also be a blend of hardly softening coal and easily softening coal, and the hardly softening coal can be a coal having a button index (CSN) of 1.5-2.0, and the easily softening coal can be a coal satisfying that a value obtained by multiplying CSN of easily softening coal by a blending ratio of easily softening coal in all coals is nit more than 5.0.

This invention provides processes and systems for converting biomass into high-carbon biogenic reagents that are suitable for a variety of commercial applications. Some embodiments employ pyrolysis in the presence of an inert gas to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases, followed by separation of vapors and gases, and cooling of the hot pyrolyzed solids in the presence of the inert gas. Additives may be introduced during processing or combined with the reagent, or both. The biogenic reagent may include at least 70 wt %, 80 wt %, 90 wt %, 95 wt %, or more total carbon on a dry basis. The biogenic reagent may have an energy content of at least 12,000 Btu/lb, 13,000 Btu/lb, 14,000 Btu/lb, or 14,500 Btu/lb on a dry basis. The biogenic reagent may be formed into fine powders, or structural objects. The structural objects may have a structure and/or strength that derive from the feedstock, heat rate, and additives.

A smelting apparatus for smelting metallic ore comprising a furnace having a continuous curved wall and end walls defining a longitudinal volume having a longitudinal axis in a horizontal direction. The continuous curved wall has a lowermost area. The longitudinal volume is divided in at least three longitudinal layers comprising a top layer within which gasified fuel is combusted for creating a hot gas composition to release, from the metallic ore, at least molten metal and slag, a lowermost layer at the lowermost area for holding molten metal, and a mid-layer above the lowermost layer in which the slag accumulates. The present document also describes processes using the smelting apparatus for producing ferrous and non-ferrous minerals from a metallic ore.

This invention provides processes and systems for converting biomass into high-carbon biogenic reagents that are suitable for a variety of commercial applications. Some embodiments employ pyrolysis in the presence of an inert gas to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases, followed by separation of vapors and gases, and cooling of the hot pyrolyzed solids in the presence of the inert gas. Additives may be introduced during processing or combined with the reagent, or both. The biogenic reagent may include at least 70 wt%, 80 wt%, 90 wt%, 95 wt%, or more total carbon on a dry basis. The biogenic reagent may have an energy content of at least 12,000 Btu/lb, 13,000 Btu/lb, 14,000 Btu/lb, or 14,500 Btu/lb on a dry basis. The biogenic reagent may be formed into fine powders, or structural objects. The structural objects may have a structure and/or strength that derive from the feedstock, heat rate, and additives.

A method for detecting a fluctuation of a solidified layer, and a method for operating a blast furnace by employing the relevant method. In the method for detecting a fluctuation of a solidified layer, the fluctuation of the solidified layer in the lower part of a blast furnace is detected by using the amount of heat supplied to pig iron in the lower part of the blast furnace and the amount of heat in the pig iron tapped in a predetermined period.

A method for detecting a fluctuation of a solidified layer, and a method for operating a blast furnace by employing the relevant method. In the method for detecting a fluctuation of a solidified layer, the fluctuation of the solidified layer in the lower part of a blast furnace is detected by using the amount of heat supplied to pig iron in the lower part of the blast furnace and the amount of heat in the pig iron tapped in a predetermined period.