30results about How to "Improve converter operating rate" patented technology

The present invention provides a siliconeisen iron melt blowing and refining method in a converter, and the method includes the steps as follows: (1) waste steel and iron melt are loaded into the converter, and oxygen blowing and steel making begin, the oxygen flux is 900Nm3/min to 1050Nm3/min, the height that the oxygen gun spraying head departs the metal liquid surface in the melt pond is 1.8-3.0m; (2) a first batch of slag charge is added after oxygen is blown in the first batch of the slag charge is 60-80 percent of the total slag charge, and the rest slag charge can be charged in 2-3 batches after the first batch of the slag charge is melted. The consumption of the slag charge: the lime 18-28kg/t steel, the light calcined dolomite 15-25kg/t steel, the ironstone 5-10kg/t steel, the carbonaceous heat generating agent 0-7kg/t steel, the compound slag 0-6kg/t steel; and the rest process are same as the prior art. The oxygen blowing duration of the present invention decreases 1.8min per furnace averagely, and the problem that the heat quantity is short and the slag forming is difficult can be solved simultaneously, and the present invention can make the converter steel-making to produce efficiently.

The invention provides a fast maintenance method for a furnace lining of a deslagging surface of a converter. The fast maintenance method for the furnace lining of the deslagging surface of the converter is applied to the technical field of iron and steel smelting processes, and comprises the maintenance steps of deslagging the converter, and remaining high-temperature residual furnace slags in the converter; adding bar steel scraps having temperature difference with the residual furnace slags into the converter, precipitating and condensing high-melting-point mineral substances in the furnaceslags under the action of the temperature difference of the bar steel scraps and the residual furnace slags, and adhering to the deslagging surface of the converter so as to replace a fettling material; and statically cooling the converter, and after finishing cooling, accomplishing the fast maintenance operation for the furnace lining of the deslagging surface of the converter. According to thefast maintenance method for the furnace lining of the deslagging surface of the converter provided by the invention, no cost input of the fettling material is required, the problems of the adverse effect on fettling and the environment pollution due to too long or too short sintering time are avoided, the molten steel end point components are ensured, the fettling time is effectively shortened, the converter operability is improved, and meanwhile, the fast maintenance method for the furnace lining of the deslagging surface of the converter has the characteristics of fast maintenance speed, good fettling effect, low fettling cost, safety, environment protection and the like.

The invention relates to a low-cost and high-efficiency converter fettling process, and belongs to a smelting production technology of a converter. The method comprises the following steps: adding a magnesian slagging material when a converter starts for blowing by 2 minutes according to the adding amount of 30 kg/t, and stopping adding iron-containing slag materials 3 minutes before a final blowing point; and wagging the converter till the inclination angle is 60 to 70 degrees according to a slag supplementing large-area part, adding prepared fettling bricks into the converter according to a proportion of 200 to 300 pieces of fettling bricks in 80 tonnage of the converter, rotating the converter along small amplitude when the fettling bricks are added, backwards slowly wagging the converter to enable the fettling bricks to be fully mixed with furnace slag after a waste steel pipe is extracted out of the converter, then wagging the converter till the inclination angle is 85 to 95 degrees, standing for 35 to 45 minutes to enable the viscosity of the furnace slag to be increased, wrapping the fettling bricks, and attaching the fettling bricks to a furnace lining. According to the low-cost and high-efficiency converter fettling process, the after-fettling sintering time is shortened by 20 minutes, and the converter working efficiency is improved; the fettling bricks can prolong the use time by 8 hours, and no phenomenon of falling of the fettling bricks is caused; the use amounts of the fettling bricks, large-area fabrics and gunning mixes is reduced; and safety accidents caused by falling of the fettling bricks are reduced.

The invention relates to a method for repairing a converter through waste magnesia carbon bricks. The method comprises the following steps that the to-be-repaired converter is tapped; terminal slag after tapping is directly poured without slag splashing until to-be-used brick fillers are covered with the terminal slag; a pre-calculated amount of brick fillers are added into the to-be-repaired converter, and forms a molten material together with the terminal slag; according to the converter repairing position, the converter is shaken, and thus the molten material can cover the to-be-repaired position; the to-be-repaired converter is sintered for 30 minutes or longer until the terminal slag is solidified; and iron is fed, and next batch of smelting is conducted. According to the method for repairing the converter, the problems of long sintering time, poor converter repairing effect, high converter repairing cost, serious environmental pollution and the like can be effectively solved, byreasonably controlling converter terminal slag, the effect that a mixture of the converter terminal slag remaining in the converter and the waste magnesia carbon bricks is effectively bonded to the repairing position of a converter lining is achieved, and finally the broken converter is repaired.

The invention relates to a production method of converter smelted low-sulphur steel. The production method comprises following steps: 1, molten iron KR stirring desulfurized lime powder, fluorite, and aluminium slag are mixed at a ratio of 10:1:1, wherein ladle slagging-off rate is controlled to be 90% or higher, and the S content of molten iron put into a furnace is controlled to be 0.003% or lower; 2, reactor washing after smelting of a former batch of non low sulphur steel and before smelting of a first batch of low-sulphur steel is carried out; 3, remaining slag and double slag operation is adopted in smelting of low-sulphur steel. According to the production method, reactor washing, remaining slag, and double slag treatment are combined for smelting in a converter, and reactor washing after smelting of a former batch of non low sulphur steel and before smelting of a first batch of low-sulphur steel is carried out, so that the sulphur introduced by remaining slag operation of the first batch of low-sulphur steel smelting is reduced, combination of remaining slag and double slag is beneficial for stable control of end point low sulphur content, converter end point sulphur content is controlled to be 0.005% or lower stably, the lowest sulphur content is 0.001%, technical guarantee is provided for development of low-sulphur novel steel; and at the same time, converter average smelting period is shortened by 4min or longer, converter operation efficiency is increased, and production capacity is increased.

The invention relates to the field of ferrous metallurgy, in particular to a method for repairing a converter lining. The method is characterized by comprising the steps of reserving a defined amount of furnace slags according to the mass ratio between the furnace slags and magnesia carbon bricks to be added after tapping of a converter is finished, then conducting hardening and tempering on the furnace slags by adding MgO particles and dolomite, jetting and shaking up the furnace slags through nitrogen, and then adding the magnesia carbon bricks for sintering. By means of the method, the lining repairing effect is improved remarkably, the time for repairing a furnace is shortened, and the converter operation rate is improved; the labor intensity of workers is reduced remarkably, and the implementation safety is high.

The invention belongs to the field of metallurgy, and particularly relates to a rapid converter protection method for a front large surface of a converter. The method comprises the steps that nut coke is added to deoxidize and adjust final slag according to a converter end point oxygen determination and oxygen activity value at the tapping time, the oxidability of the slag is reduced, the final slag FeO is adjusted to 7-10%, then raw magnesite and waste bar cutting heads are poured into the converter from the front of the converter by using a waste steel hopper, the raw magnesite is rapidly decomposed into a high-melting-point substance MgO in a high-temperature environment in the converter, and a large amount of heat is absorbed, so that high-melting-point substances such as MgO, C2S and C3S in the slag are rapidly separated out and condensed and are adhered to the waste cutting heads of the bars, and a structure similar to reinforced concrete is formed and is firmly combined on the converter lining. The method is easy to implement, low in cost, short in sintering time, long in converter protection period, beneficial for improving the converter operation rate and capable of helping enterprises to increase the yield and the benefits.

The invention discloses a converter slag mending material which is mainly characterized in that: in the converter smelting process, the sigma FeO in the converter slag is controlled to 8%-12%; a reductant active metal or alloy thereof is added in the slag after tapping, so that all of FeO in the slag is reduced, and a slag system material is turned into a CaO-SiO2 binary system or CaO-MgO-SiO2 ternary system refractory material; and the refractory material is adhered on a furnace wall through rocking a furnace or N2 splashing, thereby achieving the fettling purpose. Because the technical scheme is adopted in the invention, compared with the prior art, the converter slag mending material has the advantages that operation is simple, practicable and rapid and the effect is good.

The invention discloses a method for repairing a steel tapping face furnace lining through final slag of a rotating furnace. According to the method, in the furnace repairing process, at first, when smelting and slagging are carried out, metallurgy lime and light burnt dolomite are added to molten steel according to the weight proportion of 3:2; when slag is poured, the left slag amount is controlled to account for 7%-8% of the total charge weight of the rotating furnace; after the molten steel is discharged completely, the residual slag is treated for 1-2 min, the temperature of the furnace slag is reduced properly, viscosity of the furnace slag is increased, then the rotating furnace inclines, the final slag of the rotating furnace is flatly laid to cover the corrosion portion of the steel tapping face furnace lining, power of the rotating furnace is off, and the final slag is cooled statically for over 8 h. According to the method, the corrosion portion of the steel tapping face furnace lining is directly repaired through the slag of the rotating furnace, the high-temperature furnace slag has good mobility and can be laid on the corrosion portion of the furnace lining flatly, high-melting-point substances such as 2CaO, SiO2, MgO, 3CaO and SiO2 in the furnace slag are mutually dispersed, mineral of the same kind is recrystallized, the high-temperature furnace slag is cooled and solidified on the corrosion portion of the furnace lining, the effect of maintaining the furnace lining is achieved, the cost investment of repairing mass is not needed, the frequency of furnace repairing is effectively reduced, the operation rate of the rotating furnace is increased, the furnace repairing effect is good, the furnace repairing cost is low, and use is safe and environmentally friendly.

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 relates to a control method for preventing earlier-stage explosion venting of converter dry dedusting, and the earlier-stage control of converting is reinforced. The control method for preventing earlier-stage explosion venting of converter dry dedusting comprises the following steps that (1) a molten iron sample is obtained in a desulphurization station and sent to a test cabinet for a chemical examination as soon as possible, and chemical examination components of the molten iron sample in the test cabinet are sent to a converter second stage; (2) the lance position of an oxygen lance and the blowing oxygen flow are confirmed according to the content of molten iron silicon before converting of the converter second stage is started, and a control corresponding table of the lance position of the oxygen lance and the flow is sent to a converter first stage PLC; and (3) after converting is started, the converter first stage PLC controls the blowing oxygen flow and the oxygen lance lance position according to the converting time schedule. The control method for preventing earlier-stage explosion venting of converter dry dedusting has the advantages that the reasonable converting flow and lance position are confirmed according to a different molten iron silicon quantity, the silicon manganese oxidizing period of converting is stably spent, the phenomenon that the reaction in a furnace is too intense is avoided, and the CO generating speed is slowly increased, so that the explosion venting limitation of CO and O2 in smoke gas is missed. According to the control method for preventing earlier-stage explosion venting of converter dry dedusting, the oxygen flow and lance position in the earlier stage of converting are reasonably controlled, and zero explosion venting of earlier-stage converting dry dedusting is achieved.

The invention discloses a technology for processing vanadium extraction semi-steel. The technology includes technological processes of (1), feeding pig iron; (2), carrying out iron charging; (3), carrying out blowing; (4), adding coolants; (5), terminating blowing. Molten pig iron added during production according to the technology comprises chemical components including, by weight, 4%-5% of C, 0.08%-0.3% of Si, 0.2%-0.5% of Mn, 0.25%-0.3% of V, less then or equal to 0.25% of P, less than or equal to 0.07% of S and 93.58%-95.47% of Fe. The technology has the advantages that the original double-slag vanadium extraction smelting is replaced with semi-steel vanadium extraction, the yield of double-slag vanadium slag is approximately 30 Kg/t steel, the comprehensive grade is higher than 13%, and good benefits can be created for companies; slag splashing effects of semi-steel smelting converters can be obviously improved after semi-steel vanadium extraction is adopted, the fettling frequencies can be lowered, the operation rate of the converters can be increased, accordingly, the production efficiency can be improved, and the enterprise benefits can be increased.

The invention discloses a method for thermally replacing a furnace bottom of a high-flow top-bottom combined blown converter, belongs to the technical field of converter steelmaking, and solves the technical problems of bottom blowing closing and combined blowing effect loss caused by erosion of a bottom gun at the furnace bottom of a carbon steel smelting top-bottom combined blown converter. Comprising the following steps: blowing down a furnace; dismounting a gas distribution pipe connected with a bottom gun of an old furnace bottom; dismounting the old furnace bottom; cleaning a residual furnace lining at the combined part of a furnace body and the furnace bottom; filling a repairing material into a circular seam at the connecting part of the new furnace bottom and the furnace body; baking the furnace bottom and the circular seam material; finishing hot replacement of the new furnace bottom, and recovering smelting of the converter. Full-furnace-service large-flow bottom blowing smelting can be achieved, steel material consumption of the converter is remarkably reduced, production cost is reduced, one set of furnace body is matched with 2-3 sets of furnace bottoms, the service life of the converter can reach the high level of 8000-10000 times, refractory materials of the furnace body can be fully utilized, the turnover occupation time of the converter is shortened, and the converter operation rate can be improved.

This invention discloses method and apparatus for maintaining and removing slag from sublance of steelmaking top-bottom composite blown converter. The method solves the problems of adverse effects and many malfunctions caused by slag adhered to sublance. The method comprises: brushing slag, maintaining sublance and removing slag on the probe end during sublance lifting process after testing in converter. Therefore, the sublance can receive maintenance in time, and the method has such advantages as simple process, good slag removing effect, and few malfunctions. The brushing apparatus is easy to adjust, use and maintain. The converter with cleaned sublance has such advantages as high productivity, and short smelting period.