37results about How to "Shorten the smelting process" patented technology

The invention provides an annealing-free low-carbon steel coil rod and a production method thereof. The annealing-free low-carbon steel coil rod comprises the following chemical components: 0.04-0.10% of C, 0.01-0.10% of Si, 0.20-0.35% of Mn, at most 0.015% of P, at most 0.010% of S, at most 0.0060% of N, 0.0030-0.0060% of total oxygen, 0.0020-0.0080% of total aluminum, at most 0.1% of inevitable impurity and the balance of iron. The manufacturing method comprises the steps of converter smelting, LF (ladle furnace) refining, continuous casting and rolling, wherein incomplete deoxidation occurs at the tapping side of a converter, the aluminum content of molten steel is reduced by using the high oxygen activity of the molten steel, the carbonization of the molten steel in the refining process is inhibited, bloom protection casting is performed, the temperature for double module input is controlled at 900-920 DEG C, the loop laying temperature is 870-900 DEG C, the speed of a roller way is 0.2-0.4 m/s, and a blower is closed. Thus, the vacuum treatment procedure is omitted, the technical process is shortened, the production cost is lowered, and the requirement of users for canceling the annealing technique in the drawing process is satisfied. For the annealing-free low-carbon steel coil rod produced according to the components and the production method provided by the invention, the grain size is controlled at 20-30 um, the tensile strength is no more than 350 MPa, and the reduction of area is no less than 75%.

The invention relates to a reduction steel-making method. The reduction steel-making method comprises the following steps of: (1) carrying out initial reduction reaction on iron ore materials entering a prereduction zone in a furnace; (2) carrying out a reduction reaction simultaneously when heating and smelting the mixture entering a high temperature zone in the furnace by an electric arc or a plasma arc; (3) carrying out depth reduction reaction on molten steel entering a molten pool in the furnace to form qualified molten steel; and (4) periodically discharging the molten steel and slag from a tap hole and a slag hole. The invention further provides a reduction steel-making device. According to the reduction steel-making method and the reduction steel-making device, the production flow is short, the overall land occupation is small, ore to finished product metal yield is high, the energy consumption is low, carbon coke and a large amount of oxygen are not used, iron alloy is not needed or a small amount of iron alloy is needed except that a special steel grade is made, the carbon emission and the exhaust emission in a smelting process are reduced, and energy saving and emission reduction are facilitated.

The invention belongs to the technical field of comprehensive utilization of metallurgical resources, and in particular relates to a comprehensive utilization method of directly reducing vanadium-titanium ore hot-pressing blocks in a rotary hearth furnace and melting in an electric furnace. The method comprises the following steps: (1) blending vanadium-titanium ore mineral powder with bituminous coal powder, heating mixed powder and carrying out hot-press molding so as to obtain the vanadium-titanium ore hot-pressing blocks; (2) putting the vanadium-titanium ore hot-pressing blocks into the rotary hearth furnace by covering multiple layers of materials on the vanadium-titanium ore hot-pressing blocks and carrying out direct reduction via thick material layers; (3) melting products obtained by reducing the vanadium-titanium ore hot-pressing blocks in the rotary hearth furnace so as to obtain vanadium-containing molten iron and titanium slag; and (4) carrying out vanadium blowing and steelmaking on the vanadium-containing molten iron so as to obtain vanadium slag and a steel ingot, wherein the vanadium slag can serve as a raw material for preparing titanium dioxide. The method which is used for preparing the vanadium-titanium ore hot-pressing blocks has the advantages of low production cost, high production efficiency, low energy consumption, good quality of the vanadium titanium ore hot-pressing blocks and the like. Thus, the economy of the process of directly reducing vanadium-titanium ores in the rotary hearth furnace and melting in the electric furnace is obviously improved.

The invention provides a method for smelting high-grade pipe line steel with a RH single-link process. During a converter tapping process, high aluminum content in molten steel is controlled, such that desulfurization and impurity control in subsequent refining process can be benefited. During an RH vacuum refining stage, a desulfurization agent is added, and S content in the molten steel is controlled no higher than 0.0020%; oxygen blowing is carried out upon the molten steel, and a reaction is carried out between oxygen and aluminum in the molten steel, such that aluminum content in the molten steel is controlled at 0.03-0.05%. Also, heat loss during the desulfurization process is supplemented, and the impurity is converted into mainly clustered Al2O3 impurity which is easy to remove; and calcium treatment and soft blowing are carried out, such that the impurities in molten steel is mainly CaS impurities of small particles with deformation coefficient close to 1. According to the method provided by the invention, X80 pipeline steel quality requirement can be achieved, production process flow is short, and cost can be substantially reduced.

The invention discloses a low-nitrogen boron-containing steel smelting method for improving the boron element yield. Converter end point boiling tapping is conducted, the frequency that molten steel absorbs nitrogen from air is reduced, a slag modifier and lime are added after converter tapping is finished for adjusting slag oxygen potentials and components, and in the tapping process, a steel ladle is subjected to bottom blowing and stirring in the whole process; after tapping is finished, molten steel is conveyed to be subjected to RH treatment, after the steel ladle is conveyed in place, vacuum pumping is conducted, C in the molten steel is utilized for deoxygenation, and after the oxygen content is reduced to be 0.02% or below, aluminum is added for deoxygenation and alloying, the 1.0-3.5 kg/t of slag modifier is added in the slag face of the steel ladle, and after all the alloy and the slag modifier are added, clean circulation is conducted for 5 min or longer time, T.O in the molten steel is smaller than or equal to 0.002%, the steel slag T.Fe+MnO is smaller than or equal to 2.0%; then, a boron-iron alloy is added, clean circulation is conducted for 8 min or longer time, andvacuum breaking and tapping are conducted. During RH tapping, the boron yield reaches 89% or above, the content and the yield of the boron element in the molten steel are stably controlled, BN precipitation in the later continuous casting process can be reduced, and important significance is achieved for stabilizing the mass and performance of the boron containing steel.

The invention relates to a preparation method of a silicon steel thin strip, belongs to the technical field of metal material smelting, and solves the problems of large resource consumption and influence of residual oxygen and inclusions on steel quality in an existing silicon steel thin strip preparation process. The preparation method of the silicon steel thin strip comprises the following steps: step 1, preparing a silicon-iron-carbon alloy thin strip; step 2, decarbonizing the silicon-iron-carbon alloy thin strip to obtain a silicon steel thin strip; and 3, detecting the carbon element distribution, the microstructure, the phase, the average carbon content and the magnetic property of the thin strip. According to the preparation method of the silicon steel thin strip, processes such asconverter smelting are omitted, and the preparation method has important significance for saving energy consumption investment, shortening the smelting process, reducing the production and protectingthe environment.

The invention relates to a method for smelting silicon wafer cutting waste under micro-negative pressure, belonging to the technical field of silicon regeneration and recovery by pyrometallurgy of silicon wafer cutting waste. The invention aims to solve the problems that silicon powder is easy to oxidize in the smelting process and impurity removal efficiency is low in the smelting process due tothe existence of moisture in the pyrometallurgy silicon recovery process of silicon wafer cutting waste. According to the invention, a micro-negative pressure device is moved to a position over a smelting furnace opening, and a vacuum device of the micro-negative pressure device is started to enable silicon wafer cutting waste to undergo micro-negative pressure smelting, so oxidation loss of superfine silicon powder in the smelting process is avoided, volatile impurities in silicon are removed, and synchronous refining of silicon melt is achieved. According to the invention, a micro-negative pressure environment is created above the silicon melt, so smoke can be prevented from escaping in the silicon smelting process, and the environmental influence is reduced. The method is simple in equipment requirement, easy to operate, friendly to environment and suitable for large-scale industrial production.

The invention discloses a boron bearing steel smelting technological method for improving the boron yield. The method sequentially comprises the steps that S1, the converter process is implemented, specifically, alloy is added in the steel tapping process for deoxidation alloying, after steel tapping is finished, a slag modifier and lime are added into the ladle slag surface to control the slag component and the oxygen potential, argon is blown into the bottom of a steel ladle in the whole steel tapping process, and molten steel is kept being stirred instead of boiling strongly; S2, the VOD process is implemented, specifically, after the converter process is finished, the molten steel is conveyed to VOD for treatment, the steel ladle is connected with bottom blowing after being transported in place, vacuumizing treatment is conducted, degassing and inclusion removal are conducted while the high-vacuum state is kept, ferroboron is added in the later period of the VOD process, high-vacuum circulation continues to be kept after the ferroboron is added, and finally, the molten steel is conveyed out to be subjected to the continuous casting process; and S3, the continuous casting process is implemented, specifically, protective casting is adopted, and nitrogen increment and secondary oxidation of the molten steel are prevented. According to the boron bearing steel smelting technological method, the technological process is short, the production cost is low, operation is easy, the boron yield is high, and the content of boron in the molten steel is stable.

The invention relates to a smelting and casting method for titanium-contained metal. The method comprises the following steps that ingredient calculation is calculated, and specifically, ingredient calculation is carried out according to the component content requirement of an alloy and the component content in all raw materials; an alloy bag is made, specifically, according to an ingredient calculation result, a required intermediate alloy and required elementary substances are weighed, and the alloy bag is made; electrode pressing is conducted, specifically, a main raw material is used for being wrapped around the alloy bag and is pressed into an electrode, and the end, close to the electrode, of the alloy bag can be exposed; induction smelting is carried out, specifically, the pressed electrode is baked in a furnace, and is inductively smelted into a titanium-containing metal liquid according to the matched vacuum and/or argon filling condition and an induction power loading curve;and casting is conducted, specifically, the superheat degree of the smelted titanium-contained metal liquid is improved, and the metal liquid is cast to form the titanium-contained metal. According tothe smelting and casting method for the titanium-contained metal, the smelting process flow of the titanium-contained metal can be shortened, an alloy ingot with high uniformity and high mechanical property can be obtained through single smelting, and the direct casting can be conducted through single smelting.

The invention provides a method for removing sulfur and phosphorus from iron ore powder through microwave hydrogen reduction, and relates to the technical field of hydrogen metallurgy and microwave metallurgy. Obtaining the temperature and the molten state of a metal phase in the iron ore powder; the microwave irradiation power is controlled according to the temperature and the molten state, microwave irradiation is conducted on the iron ore powder, so that no liquid phase is generated in the reduced metal iron phase, and reducing gas is introduced for step-by-step reduction of iron oxide; introducing protective gas into the reduced metal iron phase, and recovering to room temperature to obtain reduced iron powder; and carrying out magnetic separation on the reduced iron powder to obtain target reduced iron powder. According to the invention, the hydrogen reduction effect and the gasification dephosphorization and desulfurization effects can be promoted. High-efficiency reduction at a low temperature is achieved, the content of sulfur and phosphorus in raw materials is controlled, the cleanliness of steel is improved, the difficulty of desulfurization and dephosphorization in the subsequent molten metal smelting process can be reduced, iron ore powder can be reduced to directly produce iron powder, and the smelting process is shortened.