Some implementations provide an integrated system that includes: a wastewater treatment system configured to process wastewater released by one or more furnaces at a steelmaking plant, and generates reused wastewater using the wastewater; a heat recovery apparatus configured to utilize exhaust gas from the one or more furnaces at the steelmaking plant, and heat the reused wastewater generated by the wastewater treatment system above a threshold temperature; and a generator configured to receive, through a water inlet, the reused wastewater heated above the threshold temperature; and an absorption system arranged in circulation with the generator, and wherein the reused water is supplied above a threshold amount such that the generator drives the absorption system and produces cooled air inside the steelmaking plant.

Disclosed are processes for recycling chromium oxide and producing chromium-alloy steel. Chromium oxide is reduced to metallic chromium and metallic chromium is mixed with steel to form chromium-alloy steel.

A seawater corrosion-resistant marine engineering steel and a preparation method thereof are provided. The seawater corrosion-resistant marine engineering steel consists of the following chemical compositions in percentage by mass: C: 0.011-0.069%, Si: 0.11-0.29%, Cr: 1.51-1.99%, Nb: 0.02-0.05%, Zr: 0.01-0.02%, RE: 0.0034-0.02%, and the balance of Fe and inevitable impurities. The mass percentages of Zr element and RE element also satisfy the following formulas: 0.01%<Zr+RE<0.02%, and Zr/RE=1-3. The marine engineering steel is designed with cheap chemical compositions of low carbon, low silicon and medium chromium, and is completely free of valuable corrosion-resistant metal elements such as Ni and Cu. Instead of the traditional Al deoxidization technology, Si deoxidization assisted by ZrRE composite deoxidization is used to form a fine, dispersed and uniform composite oxysulfide.

A method for producing a high purity high carbon molten chrome product from chrome and carbon bearing material, said method comprising the steps of: (a) continuously introducing chrome compacts directly into an electric melter; (b) heating and melting the chrome compacts in the electric melter at a temperature of between about 1300 C. to about 1700 C. to form high carbon molten chrome; (c) preventing oxidation of the high carbon molten chrome via minimization of the ingress of oxygen containing gas in said heating step; (d) carburizing the high carbon molten chrome to form high carbon molten metallized chrome; (e) purifying the high carbon molten metallized chrome by reducing silicon oxides to silicon and desulfurizing the high carbon molten metallized chrome to produce the high purity high carbon molten chrome product; and (f) discharging the high purity high carbon molten chrome product from the electric melter.

A process for producing clean steel products with low nitrogen content, below 35 ppm, in a steelmaking plant comprising a direct reduced iron (DRI) source, which may be a direct reduction plant or a DRI storage facility, an electric arc furnace (EAF), a vacuum degassing system (DS), and a continuous casting system (CC) is disclosed. The process comprises a first stage of melting and refining a metallic iron charge, a second stage of tapping molten steel from the electric arc furnace (EAF) into a ladle, a third stage of exposing molten steel to a pressure below the atmospheric pressure and a fourth stage of casting molten steel to clean steel products. Optionally, the molten steel tapped from the EAF is treated in a ladle furnace (LF) prior to being treated in the degassing system (DS). The metallic iron charge fed to the EAF comprises more than 70% by weight of DRI in the form of pellets or briquettes having a carbon content above 2.5 weight %. Preferably, the metallic iron charge is fed to the EAF at a temperature of 400 C. or higher. The low nitrogen level in the steel products made according to the Application is achieved by forming a first foamy slag in said first process stage and is maintained in a foamy state by controlling the feed of fluxes, oxygen, and carbonaceous materials to the EAF and by forming a second slag, after molten steel is tapped from the EAF, having a predetermined composition capable of continuing the desulfurization and providing a thermal and chemical insulation to prevent nitrogen pickup and promote nitrogen removal of molten steel. The process also comprises carrying out one or more of the following actions: (a) controlling the concentration of nitrogen and sulfur in the raw materials at each process stage, (b) promoting nitrogen removal from steel, (c) decreasing the time spent by the molten steel at each process stage and between each and subsequent process stages, and (d) preventing nitrogen pickup by the molten steel all along said process stages. Steel products made according to the Application comprise the following elements expressed in weight %: C0.05%, Si4.5%, Al2.0%; Mn2.0%; P0.20%; Ni0.200%, Cu0.200%; N0.0030%, Ni0.200%, S0.0035%.

A process for producing clean steel products with low nitrogen content, below 35 ppm, in a steelmaking plant comprising a direct reduced iron (DRI) source, which may be a direct reduction plant or a DRI storage facility, an electric arc furnace (EAF), a vacuum degassing system (DS), and a continuous casting system (CC) is disclosed. The process comprises a first stage of melting and refining a metallic iron charge, a second stage of tapping molten steel from the electric arc furnace (EAF) into a ladle, a third stage of exposing molten steel to a pressure below the atmospheric pressure and a fourth stage of casting molten steel to clean steel products. Optionally, the molten steel tapped from the EAF is treated in a ladle furnace (LF) prior to being treated in the degassing system (DS). The metallic iron charge fed to the EAF comprises more than 70% by weight of DRI in the form of pellets or briquettes having a carbon content above 2.5 weight %. Preferably, the metallic iron charge is fed to the EAF at a temperature of 400 C. or higher. The low nitrogen level in the steel products made according to the Application is achieved by forming a first foamy slag in said first process stage and is maintained in a foamy state by controlling the feed of fluxes, oxygen, and carbonaceous materials to the EAF and by forming a second slag, after molten steel is tapped from the EAF, having a predetermined composition capable of continuing the desulfurization and providing a thermal and chemical insulation to prevent nitrogen pickup and promote nitrogen removal of molten steel. The process also comprises carrying out one or more of the following actions: (a) controlling the concentration of nitrogen and sulfur in the raw materials at each process stage, (b) promoting nitrogen removal from steel, (c) decreasing the time spent by the molten steel at each process stage and between each and subsequent process stages, and (d) preventing nitrogen pickup by the molten steel all along said process stages. Steel products made according to the Application comprise the following elements expressed in weight %: C0.05%, Si4.5%, Al2.0%; Mn2.0%; P0.20%; Ni0.200%, Cu0.200%; N0.0030%, Ni0.200%, S0.0035%.

Disclosed are processes for recycling chromium oxide and producing chromium-alloy steel. Chromium oxide is reduced to metallic chromium and metallic chromium is mixed with steel to form chromium-alloy steel.

Described are steel production systems and methods, and a furnace and methods of using such furnace to produce steel. In some embodiments, the furnace may include a shell having a top portion and a bottom portion. There may be a roof connected to the top portion that can have feed ports for the introduction of a metal oxide into the furnace. The shell may include injectors that can inject a fluid into the furnace. The bottom portion may be connected to a hearth. The furnace can melt the metal oxide to form a molten bath in the hearth. The molten bath may have a slag layer and a metal layer. The fluid can reduce the metal oxide in the slag layer to form molten metal.

The present disclosure provides a high-vanadium high-speed steel and preparation method therefor, and use thereof, which relate to the technical field of high-vanadium high-speed steel. The preparation method includes: smelting raw materials to form a melt; impacting the melt to a cooling platform to form a high-vanadium high-speed steel casting billet; and performing a spheroidizing annealing treatment and a quenching and tempering treatment, so as to obtain a resultant. The spheroidizing annealing treatment includes: heating the high-vanadium high-speed steel casting billet to 820-910 C.; holding for 2-4 h; then cooling down to 450-550 C. at a cooling rate larger than 40 C./h; and then air cooling to a room temperature.

A method is provided of smelting low-nitrogen steel in an electric arc furnace by suppressing entry of nitrogen from a furnace atmosphere into molten steel during smelting of ferrous raw material. The method comprises a step of melting ferrous raw material to smelt molten steel using an electric arc furnace, in which a nitrogen-free gas is supplied around a circumferential surface of an electrode of the electric furnace and from a base end toward a tip end of the electrode. Further, a method is provided of producing steel in which the molten steel is subjected to composition adjustment then cast.