48results about How to "Reduce TFe content" patented technology

The invention discloses a blast-furnace smelting method for vanadium titano-magnetite. The method is realized in a way that: vanadium titano-magnetite accounts for 30-60% of ferrous burden which is fed into a blast furnace, and the burden comprises 40-65% of agglomerate, 30-50% of pellet and 5-10% of lump ore; the diacidic basicities CaO/SiO2 of agglomerate, pellet and blast-furnace slag are respectively controlled at 1.6-2.5, 0.6-1.0 and 1.05-1.20; the content of MgO in blast-furnace slag is controlled at 7.5-9.0%; by adding two batches of ore and three batches of coke and using the charging operation of the development center, manganese oxide ore or sintered manganese ore powder, and fluorite are incorporated into injection coal and injected into the blast furnace along with the coal powder; and thus, the content of MnO in the slag and the content of CaF2 in the slag are respectively controlled at 1.0-4.5% and 0.50-2.0%, and the oxygen-enrichment percentage of the blast furnace is controlled at 2.0-4.0%. Compared with the smelting blast furnace using the same quality and structure of the burden, the comprehensive coke ratio of the invention is reduced by 20-50kg per ton of iron, the content of TFe in the slag is reduced by 50%, and the comprehensive cost per ton of iron is reduced by 30-50 yuan. The invention has wide prospects for popularization and application.

The invention discloses a method for synchronously dephosphorization and vanadium extraction of vanadium-containing molten iron. The method comprises the following steps of: controlling temperature of vanadium-containing molten iron at 1230-1250 DEG C; carrying out oxygen-injection blowing, wherein oxygen flow is constantly controlled at 17000-25000Nm<3>/h, and the blowing process sequentially comprises three stages; the first stage starts from blowing to 1-2min of blowing, gun position is 1.6-1.8m, and lime for controlling alkalinity of slag to be 2-4 lime and 15-20kg/tFe of iron scale are added simultaneously; the second stage starts after 1-2min of blowing, gun position is 1.8-2.1m, and 5-18kg/tFe of iron scale is added in the process that oxygen-injection time is not greater than 3min; and the third stage starts from blowing to 2min of the end, 0.5-2kg/tFe of high-magnesium lime is added, and gun position is reduced to 1.6-1.8m; and blowing to end, and discharging semi-steel and vanadium slag. The method disclosed by the invention has the advantages that corrosion to lining of a vanadium extraction converter is effectively avoided, and dephosphorization and vanadium extraction are synchronously implemented; and TFe content in the vanadium slag is reduced.

The invention discloses a converter steelmaking technology, and belongs to the technical field of converter steelmaking. In smelting, the technology is mainly characterized in that: the blowing process is divided into two processes, namely the front period of blowing is a dephosphorization period, and the later period of blowing is a decarburization period. Different from a conventional smelting technology, the technology is mainly characterized in that: slag is poured when the dephosphorization period is finished, and slag is not poured when the decarburization period is finished. According to the poured dephosphorization slag, the quantity of the poured dephosphorization slag is more than 30 percent, and the TFe content of the slag is less than 14 percent. Therefore, the technology brings the biggest benefits of saving lime, reducing the consumption of steel and iron and remarkably reducing the phosphorus content together with the increment of the number of smelting furnaces after the decarburization period is finished. The technology has the other characteristic that the smelting period is not increased and is basically as same as the conventional technology.

The invention relates to a semi-steel smelting constant-pressure constant lance steelmaking method, and belongs to the technical field of semi-steel smelting. The semi-steel smelting constant-pressure constant lance steelmaking method is provided to reduce the process lance position fluctuation in order to fundamentally reduce the TFe content of final slag. A slagging system is optimized, and corundum slag is used to carry out early slagging and process slag adjustment in order to reach semi-steel smelting rapid slagging and reduce process drying. The TFe content and splash are fundamentally reduced through constant-pressure constant lance operation without special slag modifying treatment. The method has the advantages of simplicity in operation, low cost, reduction of the drying and splashing probability in the semi-steel smelting process, stationary process, and realization of control of the TFe content of the final slag within 17%.

The invention belongs to the field of steel and iron smelting, and in particular, relates to a method for producing low-phosphorus semisteel by a vanadium-contained molten iron converter. The method for producing the low-phosphorus semisteel by the vanadium-contained molten iron converter comprises the following steps: (A) after iron is mixed by a vanadium extracting converter, an oxygen reducing gun performs blowing; the oxygen flow is controlled within 1.5-3.0 Nm3/t.min in the whole process; and the bottom blowing nitrogen strength is 0.2-0.4 Nm3/t.min; (B) a gun position is controlled by above 10-30 mm according to a reference gun position before blowing by 2 min; steel making converter final slag is added at the beginning of blowing; iron-contained oxides are added after blowing by 1-2 min; the reference gun position is reduced to during blowing by 2-5 min; and the gun position is controlled by above 30-50 mm according to the reference gun position before blowing by 2 min; and (C) the semisteel and 50% of vanadium slag are discharged after blowing; in a second furnace, the oxygen supply system is the same with the first furnace; the basicity of the slag is controlled within 1.5-1.8 by the added lime quantity; the semisteel and 50% of vanadium slag are discharged after blowing; and the subsequent furnace operation is the same with the second furnace.

The invention belongs to the steel smelting field, and particularly relates to a method for dephosphorizing vanadium-containing molten iron in a vanadium extraction converter. The method aims to solve the problem that vanadium-extraction and dephosphorization efficiency is relatively low in the conventional method, and reduce TFe content in vanadium slag, so that steel material consumption is reduced, and low-phosphor semisteel is provided for a steel-making converter. The method for dephosphorizing vanadium-containing molten iron in the vanadium extraction converter comprises the following steps of: A, after iron is completely converted in the vanadium extraction converter, a deoxygenation lance is used for blowing, wherein oxygen gas flow is controlled to be 1.5-3.0Nm<3>/t.min throughout the whole process, and bottom-blowing nitrogen strength is 0.2-0.4 Nm<3>/t.min; B, lime is added when blowing starts, a lance position is controlled 10-30mm above a standard lance position 2 minutes before blowing; iron oxide scale or other oxides with high iron content are added 1-2 minutes after blowing; the lance position is controlled according to the standard lance position 2 minutes after blowing; and the lance position is controlled 30-50mm above the standard lance position 2 minutes before blowing is ended; and C, discharging semisteel and vanadium slag after blowing is ended.

The invention relates to a vanadium extracting converter slag adjusting method, and belongs to the technical field of converter vanadium extraction. The technical problem to be solved by the invention is to provide the vanadium extracting converter slag adjusting method capable of further reducing the iron loss. The method comprises the following steps: molten vanadium-titanium contained iron is mixed into a converter; a sodium salt modifying agent is added within one minute before ending of blowing; and after the blowing is finished, the tapping is performed to obtain semisteel and vanadium slag. Before the blowing is finished, the sodium salt modifying agent is adopted to adjust the slag; and the converter vanadium slag components can be controlled within a proper range before tapping of the converter, so that the purposes of reducing the vanadium slag melting point, optimizing the vanadium slag slag-iron separation effect and reducing the steel-iron consumption are achieved.

The invention provides a method for making steel by using dephosphorized steel slag. The method comprises the following steps: dephosphorizing steel slag to obtain the dephosphorized steel slag; and making steel by using the dephosphorized steel slag. The invention provides the method for making steel by dephosphorizing and recycling the converter steel slag in order to solve the problems that the converter dephosphorizing efficiency is reduced and the consumption of auxiliary materials is increased due to continuous accumulation of phosphorus in the steel slag caused by slag remaining operation of a converter. On the basis of existing slag remaining operation, the consumption of the auxiliary materials is further reduced, the converter dephosphorization efficiency is improved, meanwhile, the problem that a semisteel smelting heat source is insufficient can be relieved, the TFe content of final slag is reduced, and the remarkable cost reduction and emission reduction effects are achieved.

The invention relates to an ultra-low carbon IF molten steel peroxidation treatment method. The ultra-low carbon IF molten steel peroxidation treatment method comprises the following steps: monitoring an oxygen concentration value of a converter terminal point before converter molten steel tapping, and adding a coke powder according to a first preset proportion in the converter tapping process if the oxygen concentration value of the converter terminal point is greater than a preset concentration threshold value; monitoring a point blowing signal of the converter before converter molten steel tapping, and adding the coke powder according to a second preset proportion in the converter tapping process if the point blowing signal is received; starting the converter bottom blowing after the converter blowing is finished and a gun is lifted; adding a steel slag modifier according to a first preset dosage after converter tapping; starting steel ladle bottom blowing after the steel slag modifier is added; and performing RH vacuum treatment on the molten steel, and adding the steel slag modifier according to a second preset dosage after the treatment is completed. According to the invention, the oxygen content of the molten steel after converter tapping can be effectively reduced, and the degree of peroxidation of the molten steel is reduced.