An object is to measure the fine ratio, or the ratio of fines adhering to the surface of lumps of material, in real time with high accuracy.

A fine ratio measuring method includes a step S1 of measuring a distance between a distance measuring device and lumps of material, a step S2 of calculating a feature quantity from distance data obtained in the step S1, and a step S3 of converting the feature quantity calculated in the step S2 to a fine ratio. The feature quantity calculated in the step S2 represents distance variation calculated from the distance data obtained in the step S1. A higher fine ratio in lumps of material means greater microscopic distance variation caused by microscopic irregularities in the surface of the lumps of material in the height direction within a three-dimensional shape. Therefore, by using the distance variation as the feature quantity, the fine ratio in the lumps of material can be measured in real time with high accuracy.

A method for a blast furnace includes pulverizing coal to make pulverized coal, and pulverizing iron ore to make pulverized iron ore, and injecting the pulverized coal and the pulverized iron ore from a tuyere. A loss on ignition of the iron ore is greater than or equal to 9% by mass and less than or equal to 12% by mass, an injection rate of the pulverized coal is greater than or equal to 150 kg/tp, and an injection rate of the pulverized iron ore is greater than or equal to 2.5 kg/tp and less than or equal to 50.0 kg/tp.

A method for controlling a hot metal temperature, includes: a first control loop for calculating a target value of pulverized coal ratio such that a hot metal temperature, predicted by a physical model that is able to calculate conditions inside a blast furnace, falls within a preset target range; and a second control loop for calculating pulverized coal flow rate manipulation quantity to compensate for a deviation between the pulverized coal ratio target value and a current pulverized coal ratio actual value.

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.

Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.

A fine ratio measuring device that measures the fine ratio of fines adhering to the surface of the material in the form of lumps includes: an illumination unit that illuminates the material in the form of lumps; an imaging unit that captures an image of the material in the form of lumps and produces image data; and an arithmetic unit including a computation unit that computes a characteristic quantity of the image data produced by the imaging unit and a conversion unit that converts the characteristic quantity computed by the computation unit to the fine ratio.

A cooperative emission reduction method for sintering using an energy-carrying composite gas is disclosed. A surface of a sintered material is divided into an ignition section, a heat preservation section, a middle section, a flue gas heating section, and a machine tail section from a machine head to a machine tail of a sintering machine; according to flue gas components, temperature characteristics, and heat requirements of different sections, a hot exhaust gas is introduced to the ignition section for ignition, a hot exhaust gas is introduced to the heat preservation section and a hydrogen-rich gas is cascadingly sprayed synchronously, cascaded spraying of water vapor is coupled based on spraying of a hydrogen-rich gas in the middle section, and the high-temperature flue gas in the machine tail section and the flue gas in the ignition section and/or the heat preservation section are circulated to the heating section.

Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.

Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.

Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.