An ultra-high phosphorus molten iron low-cost smelting method for polar steel includes successively deoxidizing and tapping alloying raw materials including molten iron; performing slag adjusting and refining on the molten steel obtained in the converter smelting step to obtain a refined molten steel; vacuum degassing the refined molten steel; and performing continuous casting on the molten steel obtained after the RH degassing step to obtain a cast billet.

An ultra-high phosphorus molten iron low-cost smelting method for polar steel includes successively deoxidizing and tapping alloying raw materials including molten iron; performing slag adjusting and refining on the molten steel obtained in the converter smelting step to obtain a refined molten steel; vacuum degassing the refined molten steel; and performing continuous casting on the molten steel obtained after the RH degassing step to obtain a cast billet.

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 gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO-C central refractory with a small metal tube buried therein, and a MgO-C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO-C central refractory with a small metal tube buried therein, and a MgO-C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A blowing control method for maintaining a mushroom head of a bottom-blowing nozzle converter is disclosed. Considering the actual state of the mushroom head at the end of the bottom-blowing nozzle tip, the real-time molten steel overheating change during the blowing process, the process requirements of different stages of blowing conversion, and the macroscopic heat balance of the converter, the oxygen-carbon dioxide-lime powder blowing parameters of the inner tube of the bottom-blowing nozzle are dynamically adjusted during the converter smelting process of the bottom-blowing nozzle converter so as to control the cooling intensity, thus achieving precise control of the size of the mushroom head. The present invention maintains the basic stability of the size of the mushroom head at the end of the bottom-blowing nozzle tip, avoiding nozzle blockage caused by an oversized mushroom head and rapid erosion of the nozzle caused by an undersized mushroom head.

A blowing control method for maintaining a mushroom head of a bottom-blowing nozzle converter is disclosed. Considering the actual state of the mushroom head at the end of the bottom-blowing nozzle tip, the real-time molten steel overheating change during the blowing process, the process requirements of different stages of blowing conversion, and the macroscopic heat balance of the converter, the oxygen-carbon dioxide-lime powder blowing parameters of the inner tube of the bottom-blowing nozzle are dynamically adjusted during the converter smelting process of the bottom-blowing nozzle converter so as to control the cooling intensity, thus achieving precise control of the size of the mushroom head. The present invention maintains the basic stability of the size of the mushroom head at the end of the bottom-blowing nozzle tip, avoiding nozzle blockage caused by an oversized mushroom head and rapid erosion of the nozzle caused by an undersized mushroom head.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO—C central refractory with a small metal tube buried therein, and a MgO—C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO—C central refractory with a small metal tube buried therein, and a MgO—C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.

Various embodiments provide for a gas purging plug (10) with a ceramic refractory body (10k) with a first end (10u) and a second end (10o); the second end (10o) is in the mounted position of the gas purging plug (10) in contact with a metal melt (41); the first end (10u) is at least partially covered with a metal cover (12.1), the metal cover (12.1) comprises an opening (16) to which optionally a gas supply adapter (20) is connected; the gas purging plug (10) is designed in such a way, that a purging gas which is supplied via the gas supply pipe (30) to the opening (16) flows through the body (10k) and exits the body (10k) at the second end (10o); and wherein at least one electronic sensor (70, 70.1, 70.2, 70.3, 70.4) is in contact with the gas purging plug (10), to detect a mechanical vibration (81).