Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

A tuyere comprising an inner tube including a lower section having a first diameter, an upper section having a second diameter smaller than the first diameter, and a converging transition section having a converging angle Θ from 30° to 60° connecting the lower section to the upper section, the inner tube terminating in an inner nozzle at a downstream end of the upper section; and an outer tube surrounding the inner tube so as to create an annulus there between, the outer tube including a lower section having a third diameter larger than the first diameter, an upper section having a fourth diameter smaller than the third diameter but larger than the second diameter, and a converging transition section having connecting the lower section to the upper section, the outer tube terminating in an outer nozzle at a downstream end of the upper section.

An efficient long-service-life blowing method include the steps of introducing vanadium extraction converter flue gas and decarburization converter flue gas into an oxygen combustor; obtaining first-purity CO.sub.2—N.sub.2 mixed gas through the vanadium extraction converter flue gas; obtaining second-purity CO.sub.2—N.sub.2 mixed gas through the decarburization converter flue gas; obtaining O.sub.2—CO.sub.2—N.sub.2 mixed gas through the decarburization converter flue gas; obtaining first-purity CO.sub.2 gas through the second-purity CO.sub.2—N.sub.2 mixed gas; and using the first-purity CO.sub.2—N.sub.2 mixed gas for bottom blowing of the vanadium extraction converter, using the second-purity CO.sub.2—N.sub.2 mixed gas as a carrier gas for blowing iron ore powder into the vanadium extraction converter, and using the O.sub.2—CO.sub.2—N.sub.2 mixed gas and the first-purity CO.sub.2 gas as a carrier gas for bottom blowing of the decarburization converter and bottom injecting of lime powder into the decarburization converter.

A method to control slag foaming in a smelting process in a vessel for smelting an iron-containing feed material including the steps of: measuring vibration of the metallurgical vessel with an accelerometer at one or more positions on the vessel, comparing values derived from accelerometer data with a threshold value which indicates the onset of a slag foaming incident, and adjusting the smelting process if the value derived from the accelerometer data passes a predefined alarm value, wherein the smelting process is adjusted by adjusting the amounts of the gaseous and/or the solid components injected in the smelting process.

A method to control slag foaming in a smelting process in a vessel for smelting an iron-containing feed material including the steps of: measuring vibration of the metallurgical vessel with an accelerometer at one or more positions on the vessel, comparing values derived from accelerometer data with a threshold value which indicates the onset of a slag foaming incident, and adjusting the smelting process if the value derived from the accelerometer data passes a predefined alarm value, wherein the smelting process is adjusted by adjusting the amounts of the gaseous and/or the solid components injected in the smelting process.

A tuyere comprising an inner tube including a lower section having a first diameter, an upper section having a second diameter smaller than the first diameter, and a converging transition section having a converging angle from 15 to 35 connecting the lower section to the upper section, the inner tube terminating in an inner nozzle at a downstream end of the upper section; and an outer tube surrounding the inner tube so as to create an annulus there between, the outer tube including a lower section having a third diameter larger than the first diameter, an upper section having a fourth diameter smaller than the third diameter but larger than the second diameter, and a converging transition section having connecting the lower section to the upper section, the outer tube terminating in an outer nozzle at a downstream end of the upper section.

An efficient long-service-life blowing method include the steps of introducing vanadium extraction converter flue gas and decarburization converter flue gas into an oxygen combustor; obtaining first-purity CO.sub.2N.sub.2 mixed gas through the vanadium extraction converter flue gas; obtaining second-purity CO.sub.2N.sub.2 mixed gas through the decarburization converter flue gas; obtaining O.sub.2CO.sub.2N.sub.2 mixed gas through the decarburization converter flue gas; obtaining first-purity CO.sub.2 gas through the second-purity CO.sub.2N.sub.2 mixed gas; and using the first-purity CO.sub.2N.sub.2 mixed gas for bottom blowing of the vanadium extraction converter, using the second-purity CO.sub.2N.sub.2 mixed gas as a carrier gas for blowing iron ore powder into the vanadium extraction converter, and using the O.sub.2CO.sub.2N.sub.2 mixed gas and the first-purity CO.sub.2 gas as a carrier gas for bottom blowing of the decarburization converter and bottom injecting of lime powder into the decarburization converter.