49results about How to "Fast slag formation" patented technology

The RH vacuum treatment deep desulfurization premelting slag for ultra-low-carbon steel comprises: 48~56% CaO, 33~43% Al2O3, 0.2~5.0% MgO, 2.5~6.0% SiO2ú¼TiO2íœ1.9, Cíœ0.05 and impurity, and is prepared by electric melting the material of super 60-65% limestone and 35-40% Al2O3 powder (Al-content more than 96%). This invention improves desulfurization capacity, produces Ca(AlO2)2 convenient to preserving, and has little corrosion to RH groove.

The invention relates to a dephosphorizing agent and application thereof, belonging to the technical field of ferrous metallurgy. The dephosphorizing agent solves the problems of low dephosphorizing efficiency, high residue consumption, environment pollution and difficulty in resource comprehensive utilization in the existing calcium-oxide-based molten iron pretreatment dephosphorizing agent. The dephosphorizing agent comprises the following components in percentage by mass: 25-50% of FeOt, 20-45% of CaO, 15-30% of SiO2, 2-10% of Na2O and 3-12% of Al2O3. After being molten, the molten iron dephosphorizing can form a solid-phase/liquid-phase coexistent multiphase residue system at 1300-1400 DEG C, wherein the solid phase is a 2CaO.SiO2 phase capable of providing a place for enriching oxidized phosphorus in molten iron, so that the dephosphorizing agent has the characteristics of favorable dephosphorizing effect, low slag consumption, no fluorine and small environmental pollution and is beneficial to comprehensive utilization of dephosphorizing slag.

The invention discloses a molten iron dephosphorization agent manufactured by using converter dry-method dust-removal ash as a raw material, which belongs to the technical field of steel making and molten iron pretreatment and is applicable to converter molten iron dephosphorization treatment. The dephosphorization agent comprises the following chemical components in percentage by weight: 45 to 65 percent of CaO, 15 to 35 percent of iron oxides (Fe2O3+FeO), 5 to 15 percent of CaF2 and 2 to 6 percent of SiO2, wherein the ratio of CaO to Fe2O3+FeO+CaF2 ranges from 1.0 to 3.0, and the ratio of CaO to SiO2 ranges from 9 to 16; and the hemispherical fusion temperature of the dephosphorization agent is not more than 1,200 DEG C. The raw material of the dephosphorization agent comprises 20 to 60 percent of converter dry-method dust-removal ash, 20 to 60 percent of active lime powder and 5 to 20 percent of fluorite powder. The dephosphorization agent has the advantages that: after the converter molten iron dephosphorization pretreatment is performed by using the dephosphorization agent, the P content can be kept below 0.030 percent; the converter dry-method dust-removal ash is recycled in a steel making process; and the cost of the converter dephosphorization pretreatment is reduced considerably.

The invention provides refined slag used in a steel-making process for bearing steel, which comprises the following raw materials by weight percentage: 45-55% of CaO, 14-20% of Al2O3, 14-18% of SiO2, 3-12% of MgO, 3-8% of metallic aluminum, less than or equal to 0.15% of Ti, less than or equal to 0.050% of P+S and the balance of impurities. The granularity of refined slag is 10-40mm. The CaO/SiO2 value can be controlled in the range of 2.7-3.5. The refined slag can effectively control the form, the composition, the size distribution and the like of the impurities in steel and has obvious effect for improving the quality of the bearing steel. The slag system has the advantages of fast slag forming speed, strong deoxidation and desulphurization capability, strong adsorption capability on impurities, controllable compositions and types of impurities in steel and the like.

The invention discloses a method for improving purity of molten steel in an argon station, which comprises the following steps of: (1) adding 30 to 60kg of lime, 20 to 40kg of calcium carbide and 130 to 160kg of premelted refining slag into a steel ladle before argon blowing, and increasing argon quantity for strongly blowing argon, wherein the strong argon blow standard is that the sum of the diameters of blown open holes of the molten steel is controlled to be between 400 and 600mm; (2) after strongly blowing argon for 1 to 3 minutes, adding aluminum wires into the steel ladle; (3) after strongly blowing argon for 6 minutes together, reducing argon quantity for softly blowing argon, wherein the soft argon blow standard is that the sum of the diameters of blown open holes of the molten steel is controlled to be between 200 and 400mm, and the soft argon blow time is ensured to be more than or equal to 6 minutes; and (4) making the total argon blow time for the molten steel in the argon station more than or equal to 12 minutes, closing the argon when the temperature accords with the liquidus temperature of between 50 and 65 DEG C, and adding an alkaline covering agent and carbonized rice husks into the steel ladle. The premelted refining slag is added into the argon station, the process is easy to operate and the purity of the molten steel can be effectively improved.

The invention relates to a premelting composite slugging agent for a converter and a preparation method thereof. The slugging agent comprises raw materials of lime, ferric oxide powder, activated aluminum oxide powder, low-sulfur cement, silica powder and an activating agent, wherein the raw materials comprise the following components in percentage by mass: 15-35% of CaO, 15-35% of Fe2O3, 5-15% ofAl2O3, 5-15% of MgO, and not greater than 15% of SiO; and the slugging agent contains not greater than 0.25% of impurity element S. According to the slugging agent, the raw materials are environmentally friendly; the melting point is low; the slagging speed is high; the breathability of slags can be obviously improved; the splashing in the converting process is reduced; and meanwhile, the slugging effect in the converting process can be effectively improved through the slugging agent, and the converting process is stable; the slugging agent avoids re-drying and gun adhering; in addition, theend point oxygen of a converter can be decreased after the converting slugging effect is improved, so that the oxidization of the slags can be reduced; the steel iron consumption is decreased; and theproduction cost is reduced.

The invention discloses pre-melted refining slag comprising the following components in proportion by weight: 54-68 portions of active lime, 23-35 portions of high-alumina bauxite, 1-6 portions of borax and 2-7 portions of magnesite. The invention has the advantages of short refining time, high scorification speed, good desulfurization degree, no rephosphorization, low abrasion to a ladle liner, no caking of slags, complete smelting within two minuets after electrification and reduction of energy loss. Compared with a sintering shaft furnace, the electro-smelting has less sulphur and phosphorus-containing detrimental impurities, no pollution of liquid steel, large refining slag sulfur-washing capacity and more than 80 percent of desulfurization degree with the adoption of adequate lime; the sulfur content of an LF finished product can be controlled beneath 0.001 percent, the HR sulfur content can be controlled beneath 0.0005 percent, pulverization is avoided, and the shelf life is more than half year.

The invention discloses a method for producing calcium ferrite from iron oxide. The method utilizes an iron electrode to realize electric smelting, utilizes the iron electrode to produce calcium ferrite, prevents an additional component from entering into calcium ferrite, improves calcium ferrite purity and realizes better calcium ferrite actual use effects. In steel-making, through use of the calcium ferrite obtained by the method, a slagging rate is fast, dephosphorization efficiency is high, a lime use amount is reduced, fluorine-free steel-making is realized and environmental pollution is reduced.

The invention relates to a slag stopping material, a slag stopping method and a combined technology method of slag stopping and slag splashing protection. The sum of mass percentages of CaO, MgO and C in the slag stopping material accounts for over 40% of the total mass of the slag stopping material, igloss is smaller than 47% of the total mass of the slag stopping material, and the mass percent of C is not more than 25% of the total mass of the slag stopping material. The slag stopping method comprises the step of putting a certain amount of slag stopping material on the liquid level area over a steel tapping hole in a converter. The slag stopping material, the slag stopping method and the combined technology method of slag stopping and slag splashing protection have the following beneficial effects: roughing slag amount is reduced, the thickness of the slag blanket in a ladle is thinned obviously, the tasks of deoxidation of molten steel in the ladle and modification of top slag are relieved, the consumption of deoxidizer is lessened, the phenomena of rephosphorization and silicon pick up in the refining process of the molten steel are reduced, the consumption of slag regulating materials is lowered, the time of molten steel refining is shortened and the smelting cost is decreased; and after steel tapping is finished, the slag stopping material can be directly used as a slag splashing protection material, the use amount of the slag splashing protection material is reduced, the time of slag splashing protection is shortened and the working efficiency of the converter is enhanced.

The invention discloses a metallurgy lime powder utilization system and a technology method. The system and the technology method are mainly designed for effective recycling of lime powder in the metallurgy process. The metallurgy lime powder utilization system comprises a vibrating sieve, a lime powder ball press and a lime powder conveying unit, wherein the vibrating sieve is arranged on a lime raw material supply section and used for screening lime powder with the grain size smaller than 5 mm; the lime powder ball press is used for performing ball pressing on lime powder, and the lime powder conveying unit is used for communicating the vibrating sieve and the lime powder ball press. The lime powder conveying unit conveys the lime powder screened out by the vibrating sieve to the lime powder ball press, the lime powder ball press carries out ball pressing on the lime powder so that lime balls with the grain size being 20-40 mm and the special gravity being 1.9-2.2 t/m<3> can be obtained, and the lime balls are returned for steel making. The lime powder for metallurgy and with the grain size smaller than 50 mm is separated, recycled and used. Meanwhile, negative effects of the lime powder in the steel making and producing process are also avoided.

The invention relates to calcium aluminate for desulfurization of ultralow titanium and carbon steel and a preparation method thereof. The calcium aluminate comprises more than or equal to 94% of Ca12Al14O33, less than or equal to 2% of Ca3Al2O6, less than or equal to 2% of Ca2SiO4, less than or equal to 1.5% of MgO, less than or equal to 0.01% of pure Ti and less than or equal to 0.02% of pure carbon. The preparation method comprises the following steps of: (1) preparing materials according to the following proportions: 60-65% of CaO and 35-40% of Al; (2) mixing the proportioned raw material particles in a material mixer; (3) adding the mixed materials into a smelting furnace, and blowing fuel to heat the furnace to make furnace temperature achieve 950-1050 DEG C; (4) blowing oxygen into the furnace, heating the furnace body to 1450-1500 DEG C; and (5) cooling and crushing premelted slag into 5-30 mm blocks. The desulfurizing agent provided by the invention has the advantages of low production cost, easy for storage, low melting point, high slag melting speed, high desulfurization effect and small corrosion to refractory materials, and the carbon increase amount and the titanium increase amount of liquid steel can be effectively controlled.

The invention discloses a method for producing calcium ferrite from iron ore. The method utilizes an iron electrode to realize electric smelting, utilizes the iron electrode to produce calcium ferrite, prevents an additional component from entering into calcium ferrite, improves calcium ferrite purity and realizes better calcium ferrite actual use effects. In steel-making, through use of the calcium ferrite obtained by the method, a slagging rate is fast, dephosphorization efficiency is high, a lime use amount is reduced, fluorine-free steel-making is realized and environmental pollution is reduced.

The embodiment of the invention provides a preparation method for high calcium aluminium alloy, and the high calcium aluminium alloy. The preparation method comprises the steps of weighing and mixingraw materials uniformly to form mixtures, wherein the raw materials comprise aluminium scruff ash, calcium oxide and carbon powder; placing the mixtures in a smelting furnace for smelting to obtain smelting materials; and cooling and crushing the smelting materials to obtain the high calcium aluminium alloy. According to the high calcium aluminium alloy prepared with the above method, the aluminium scruff ash can be recycled, and the high calcium aluminium alloy is applied to the steel-making process; pollution can be reduced, and dust is not liable to produce at a production site; the slag forming speed is high, and the steel-making efficiency is improved; and subsequent desulfurization is not affected, and the cost is low.

The invention discloses a converter slag forming process for rapid slagging and belongs to the technical field of converter processes for steel production. The converter slag forming process is used for rapid slagging of a converter. According to the technical scheme, in the converter slag forming process, the rotating speed of a fan is reduced before waste molten iron is added into the converter, lime powder of a small particle size is added in advance, and waste caused when lime powder of an extremely small particle size is sucked away by the fan is avoided; in addition, an initial slagging reaction is completed under the impact of the molten iron in the molten iron charging process, the rotating speed of the fan is increased to a normal value after lime powder is added, and lime blocks are added in the converting process. By means of the converter slag forming process, the slagging speed at the earlier smelting stage of the converter is effectively increased, and meanwhile waste caused when lime of an extremely small particle size is sucked away by the fan in the smelting process of the converter is reduced. The converter slag forming process is an innovation, solves the problem that the particle size of lime can not meet both sides, which brings trouble to slagging of the converter for a long term, effectively increases the slag forming speed in slagging of the converter, reduces the lime consumption in the slagging process, lowers production cost and improves the dust removing effect.