A production method of pig iron using a blast furnace with a tuyere includes: charging a first layer containing an iron ore material and a second layer containing coke alternately in the blast furnace; and reducing and melting the iron ore material in the charged first layer while injecting an auxiliary reductant into the blast furnace by hot air blown from the tuyere, in which: an aggregate for letting through the hot air to a central portion of the blast furnace is blended into the first layer; and the aggregate contains a reduced iron molded product obtained through compression molding of reduced iron.

A valve for a PCI system of a blast furnace including a valve housing with an inlet opening, an outlet opening and a maintenance opening, a maintenance door that is adapted to close the maintenance opening in an operating position during operation of the valve and that is removable from the maintenance opening into a maintenance position, a valve member movably mounted to the maintenance door, wherein, when the maintenance door is in the operating position, the valve member is movable between a closed position for closing the valve and an open position, and, when the maintenance door is in the maintenance position, the valve member is accessible from outside the valve housing.

In some variations, the invention provides a biocarbon pellet comprising: 35 wt % to 99 wt % of a biogenic reagent, wherein the biogenic reagent comprises, on a dry basis, at least 60 wt % carbon; 0 wt % to 35 wt % water moisture; and 1 wt % to 30 wt % of a binder, wherein the biocarbon pellet is characterized by an adjustable Hardgrove Grindability Index (HGI) from about 30 to about 120, as shown in the Examples. The pellet HGI is adjustable by controlling process conditions and the pellet binder. The binder can be an organic binder or an inorganic binder. The carbon is renewable as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Many processes of making and using the biocarbon pellets are described. Applications of the biocarbon pellets include pulverized coal boilers, furnaces for making metals such as iron or silicon, and gasifiers for producing reducing gas.

In some variations, the invention provides a biocarbon pellet comprising: 35 wt % to 99 wt % of a biogenic reagent, wherein the biogenic reagent comprises, on a dry basis, at least 60 wt % carbon; 0 wt % to 35 wt % water moisture; and 1 wt % to 30 wt % of a binder, wherein the biocarbon pellet is characterized by an adjustable Hardgrove Grindability Index (HGI) from about 30 to about 120, as shown in the Examples. The pellet HGI is adjustable by controlling process conditions and the pellet binder. The binder can be an organic binder or an inorganic binder. The carbon is renewable as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Many processes of making and using the biocarbon pellets are described. Applications of the biocarbon pellets include pulverized coal boilers, furnaces for making metals such as iron or silicon, and gasifiers for producing reducing gas.

An optimization method for a directional preparation technique and efficient use of semi-coke for blast furnace injection. Firstly, the volatile and the ash content of target semi-coke are preset, and then the volatile and the ash removal percentages of a raw coal are calculated; after ash removal, several sets of dry distillation carbonization temperatures and carbonization times are obtained according to the volatile removal percentage, and the relationships between a combustion rate, abrasiveness, explosiveness and jet flow property and the carbonization temperature are respectively established to obtain the optimal actual carbonization temperature; and semi-coke for blast furnace injection is obtained at an actual carbonization temperature. The directional preparation is suitable for the semi-coke for blast furnace injection, and an optimal coal-compounding scheme is obtained, thus achieving the efficient and safe injection of blast furnace iron-making fuels, and energy conservation and emission reduction.

Provided is a blast furnace operation method that enables lowering of the reducing agent ratio of a blast furnace. The blast furnace operation method includes injecting pulverized coal through tuyeres of a blast furnace. The method includes adjusting coal containing moisture and volatile matter to form adjusted pulverized coal having a specific surface area within a range of 2 m.sup.2/g or more and 1000 m.sup.2/g or less, a lower heating value of 27170 kJ/kg or more, and a volatile matter content within a range of 3 mass % or more and 25 mass % or less. The method further includes injecting, through the tuyeres of the blast furnace, pulverized coal in which the adjusted pulverized coal, in a mixing ratio of 10 mass % or more, is mixed.

Disclosed is a blast furnace apparatus includes: a rotating chute; a plurality of tuyeres; a profile measurement device configured to measure surface profiles of a burden charged into the blast furnace through the rotating chute; and a blowing amount controller configured to control a blowing amount of at least one of hot blast or pulverized coal in each of the plurality of tuyeres, in which the profile measurement device includes: a radio wave distance meter installed on the blast furnace top and configured to measure the distance to the surface of the burden charged; and an arithmetic unit configured to derive the surface profiles of the burden on a basis of distance data for the entire blast furnace related to distances to the surface of the burden obtained by scanning a detection wave of the radio wave distance meter in the blast furnace in a circumferential direction.

Methods, apparatuses, and systems to collect fine particle coal are provided herein. For example, these methods, apparatuses, and systems may be incorporated into a coal processing plant to collect a portion of the fine particle coal that is normally lost in the system. A fine particle coal also is provided. The fine particle coal may have a particle size of 1000 μm or smaller and a water content of from about 5% to about 20%, by weight.

Methods, apparatuses, and systems to collect fine particle coal are provided herein. For example, these methods, apparatuses, and systems may be incorporated into a coal processing plant to collect a portion of the fine particle coal that is normally lost in the system. A fine particle coal also is provided. The fine particle coal may have a particle size of 1000 m or smaller and a water content of from about 5% to about 20%, by weight.

Provided is a blast furnace operation method that enables lowering of the reducing agent ratio of a blast furnace. The blast furnace operation method includes injecting pulverized coal through tuyeres of a blast furnace. The method includes adjusting coal containing moisture and volatile matter to form adjusted pulverized coal having a specific surface area within a range of 2 m.sup.2/g or more and 1000 m.sup.2/g or less, a lower heating value of 27170 kJ/kg or more, and a volatile matter content within a range of 3 mass % or more and 25 mass % or less. The method further includes injecting, through the tuyeres of the blast furnace, pulverized coal in which the adjusted pulverized coal, in a mixing ratio of 10 mass % or more, is mixed.