217results about "Tuyeres" patented technology

The invention discloses a layered, zoned and differentiated CO2 injection system and method for a blast furnace, and belongs to the technical field of ferrous metallurgy low carbon. The system comprises a CO2 supply and distribution system, a tuyere area injection module, a furnace body middle-lower part injection module and a furnace body upper part injection module. And according to the temperature gradient and atmosphere layering characteristics in the blast furnace, a differential CO2 distribution proportion and a collaborative thermal compensation strategy are adopted. An oxygen-CH4 synergistic injection device is arranged in a tuyere area, and rapid conversion of CO2 is promoted by using a high-temperature strong reducing atmosphere; a biomass charcoal synergistic injection device and an angle-adjustable nozzle are arranged at the middle lower part of the furnace body, so that efficient gasification reaction is realized; and low-concentration CO2 mixed injection is adopted at the upper part of the furnace body, so that indirect reduction reaction is promoted. According to the invention, the CO2 conversion rate is 65-80%, the coke ratio is reduced by 15-25%, the consumption of CO2 per ton of iron is 260-90Nm < 3 >, the carbon emission is obviously reduced, and the ironmaking efficiency is improved.

The invention discloses a blast furnace pulverized coal electromagnetic preheating system and process, and relates to the technical field of blast furnace ironmaking. The blast furnace pulverized coal electromagnetic preheating system comprises a pulverized coal bin, an injection tank and a mixer, a radial flow guide device is arranged at the inlet end in a rough preheating pipeline, and the radial flow guide device is used for separating materials according to the diameter and guiding the materials to move on the inner wall of the radial rough preheating pipeline; the intermediate heating device is used for forming a heating channel and heating materials moving along the middle of the coarse preheating pipeline, and a dispersing device is arranged at the outlet end of the coarse preheating pipeline and used for dispersing the materials with different particle sizes to different areas and conveying the materials into the fine preheating pipeline. According to the blast furnace pulverized coal electromagnetic preheating system and process, powder moisture is removed through coarse preheating, powder with different particle sizes is guided to be separated and move towards the inner wall of the coarse preheating pipeline, materials with different particle sizes are dispersed to different areas through fine preheating, and the powder reaches the temperature close to an ignition point.

The application provides a method for treating blast furnace tuyere coal gas leakage, comprising the following steps: taking the outside of the gap between a large tuyere sleeve and a second tuyere sleeve of a blast furnace tuyere as a polishing surface; polishing the polishing surface to form a rough surface and removing impurities on the rough surface; brushing several layers of epoxy resin on the rough surface, brushing the next layer of epoxy resin after the solidification of each layer of epoxy resin, and forming an adhesion layer after the solidification of each layer of epoxy resin. Compared with the prior art, the method in the scheme polishes and applies glue at the gap between the outside of the large tuyere sleeve and the second tuyere sleeve, forms multiple adhesion layers, blocks the gap, and prevents coal gas leakage.

The utility model provides a device for preventing a blast furnace tuyere blowpipe from sinking. The device for preventing the blast furnace tuyere blowpipe from sinking comprises a tuyere large sleeve, a tuyere medium sleeve, a tuyere small sleeve, a supporting boss, a mounting plate and a moving assembly, the tuyere medium sleeve is arranged at the rear end of the tuyere large sleeve, the tuyere small sleeve is arranged at the rear end of the tuyere medium sleeve, the supporting boss is arranged in the tuyere small sleeve, and the mounting plate is arranged in the tuyere small sleeve. The outer diameter of the supporting boss is matched with the inner diameter of the small tuyere sleeve, and the inner diameter of the supporting boss is matched with the outer diameter of a tuyere blowpipe. According to the device for preventing the blast furnace tuyere blowpipe from sinking, the tuyere blowpipe is not easy to sink when the blast furnace is in damping down due to the arrangement of each structure, so that the maintenance and repair period of workers on the blast furnace is prolonged, and the cost of the workers is reduced.

The invention relates to a microchannel single-cavity tuyere small sleeve and a blast furnace comprising the microchannel single-cavity tuyere small sleeve, the microchannel single-cavity tuyere small sleeve comprises a small sleeve body, the small sleeve body is provided with a heat exchange cavity and a cooling cavity located on the periphery of the heat exchange cavity, and the heat exchange cavity penetrates through the small sleeve body in the length direction; the cooling cavity comprises a first cavity body and a second cavity body which are distributed in the length direction. The partition plate is arranged in the second cavity and surrounds the heat exchange cavity so as to divide the second cavity into a third cavity and a fourth cavity surrounding the radial outer side of the third cavity, and the sides, away from the first cavity, of the third cavity and the fourth cavity communicate with each other; and the at least one first cooling liquid pipe is arranged in the first cavity, the first end of the first cooling liquid pipe communicates with one of the third cavity and the fourth cavity, and the second end of the first cooling liquid pipe penetrates out of the side wall, away from the second cavity, of the first cavity. The temperature of the micro-channel single-cavity tuyere small sleeve is reduced, and damage caused by too high temperature is avoided.

The operation method of a blast furnace improves the ventilation of the lower part of the blast furnace by tuyere injection of fine ore. The operation method of the blast furnace (1) of the invention is characterized in that coal is pulverized as fine coal, and an iron ore having a pulverized ignition loss of 9 mass% or more and 12 mass% or less is pulverized as fine ore, the injection rate of the fine coal is 150 kg / tp or more, the injection rate of the fine ore is 2.5 kg / tp or more and 50.0 kg / tp or less, and the fine coal and the fine ore are injected from the tuyere (2). It is preferable that the iron ore and the coal are pulverized together.

The invention relates to the technical field of pulverized coal distributors, and discloses an intelligent uniform distribution blast furnace coal injection device which comprises a conical distribution chamber, the distribution chamber comprises a lower conical barrel and an upper conical cover detachably installed on the top of the lower conical barrel, and the bottom of the lower conical barrel fixedly communicates with a powder supply pipeline. According to the intelligent uniform distribution blast furnace coal injection device, uniform distribution and maintenance-free operation can be stably realized for a long time; by means of rotating airflow formed by the built-in flow guide element, pulverized coal is fully mixed and evenly distributed in the cavity and then shunted, the deviation of the amount of pulverized coal at the outlet of each branch pipe is extremely small, and the consistency of coal injection of all tuyeres is guaranteed. The method is crucial for stable operation of the blast furnace, fluctuation of the temperature and the reducing atmosphere in the furnace caused by uneven distribution can be reduced, the anti-blocking performance is greatly improved due to the unique design of the coarse particle settling tank, coarse particles and foreign matter are actively separated and collected and cannot enter an outlet pipeline, and the risk that an outlet pipe is blocked in the past is avoided.

The utility model discloses a fully utilized inner hole structure of a blast-furnace tuyere small sleeve, relates to the technical field of blast-furnace tuyere small sleeves, and aims to solve the problems that the existing blast-furnace tuyere small sleeve is harsh in working environment, is easy to damage under the conditions of tuyere blockage, non-uniform airflow distribution at the upper part of a blast furnace or airflow fluctuation, and is not easy to damage. Meanwhile, molten iron makes direct contact with the copper wall of a small sleeve, heat flow drastically increases within an extremely short time, small sleeve melting loss can be caused, meanwhile, a necking lining is installed in the small sleeve, the size of the lining is not appropriate, the lining cannot be flush with the front section of the small sleeve, airflow entering a furnace is disordered, blast furnace inlet airflow is disordered, and the furnace condition is worsened. According to the technical scheme, the small sleeve is characterized by comprising a small sleeve body, a small sleeve air channel is formed in the center of the interior of the small sleeve body, a front air opening is reserved in the other end, located on the outer side of the small sleeve air channel, of the interior of the small sleeve body, and a surfacing layer is arranged on the outer side of the small sleeve body. And the effects of stable work, cost reduction and efficiency improvement are achieved.

The invention discloses a blast furnace smooth quantitative regulation and control method based on an operation system, and relates to the field of blast furnace regulation and control. The method comprises the following steps: classifying blast furnace operation parameters according to a raw fuel system, a charging system, an air supply system, a heat system and a slagging system, and combining influence coefficients and system weights of the parameters on blast furnace pressure difference to construct a comprehensive influence quantity; meanwhile, the blast furnace pressure difference fluctuation quantity and the center and edge temperature difference are obtained in real time, whether early warning regulation and control are needed or not is judged based on whether the comprehensive influence quantity, the blast furnace pressure difference fluctuation quantity and the center and edge temperature difference exceed respective preset threshold values or not, if yes, the early warning grade is judged, and the dominant abnormal operation system is recognized based on the influence quantity of each system; and the corresponding parameter adjustment amount is calculated according to the influence amount of the system, and regulation and control are executed according to the adjustment range limited by the early warning level, so that early and quantitative identification of the abnormal furnace condition is realized, and passive intervention only depending on a single index or a post phenomenon is avoided.

The invention relates to the field of blast furnace ironmaking, and particularly discloses electromagnetic preheating equipment for a blast furnace pulverized coal pipeline, which comprises a preheating pipe connected between a mixer and a blast furnace, the preheating pipe is made of a metal material, a plurality of channels for pulverized coal to pass through are arranged in the preheating pipe, and an electromagnetic heating coil is sleeved outside the preheating pipe. After alternating current is introduced into the electromagnetic heating coil, an alternating magnetic field is generated, the preheating pipe generates eddy current and then emits heat, heat is transferred to pulverized coal and nitrogen flowing in the pipeline, the temperature of the pulverized coal rises, and the purpose of preheating the pulverized coal is achieved. The electromagnetic heating coil generates eddy current in the metal preheating pipe to generate heat, so that non-contact heating is realized, and heat radiation loss and open fire hidden dangers of traditional resistance heating are avoided; the alternating magnetic field directly acts on the preheating pipe, and the heat efficiency is obviously higher than that of an indirect heating mode; heat is uniformly conducted to pulverized coal and nitrogen in the channel through the pipe wall, and local overheating or heating dead angles are avoided.

A method for a blast furnace includes pulverizing coal to make pulverized coal, and pulverizing iron ore to make pulverized iron ore, and injecting the pulverized coal and the pulverized iron ore from a tuyere. A loss on ignition of the iron ore is greater than or equal to 9% by mass and less than or equal to 12% by mass, an injection rate of the pulverized coal is greater than or equal to 150 kg / tp, and an injection rate of the pulverized iron ore is greater than or equal to 2.5 kg / tp and less than or equal to 50.0 kg / tp.

A method for operating a blast furnace with which, even in the case where there is an increase in the powder ratio of coke to be charged into the blast furnace, it is possible to achieve the stabilization of blast furnace operation. The method includes blowing air through a tuyere disposed in a lower part of the blast furnace, successively measuring a particle size distribution of coke transported to the blast furnace, and adjusting at least one of a blast volume and a coke ratio in accordance with an index derived from the particle size distribution.

The utility model belongs to the technical field of blast furnace cooling devices, and relates to a novel cooling system on-line monitoring device which comprises a tuyere sleeve, a water inlet pipe and a water outlet pipe are respectively connected onto the tuyere sleeve, connecting flanges are arranged at the tail ends of the water inlet pipe and the water outlet pipe, and turbine flowmeters are arranged in the water inlet pipe and the water outlet pipe. A temperature display screen is arranged on the side wall of the tuyere sleeve and comprises a temperature sensing probe, one end of the temperature sensing probe is inserted into the tuyere sleeve, a bearing is arranged at the other end of the temperature sensing probe and connected with a rotary connecting block, the rotary connecting block is connected with a fixed connecting block, and a liquid crystal screen is arranged on the fixed connecting block. The blast furnace tuyere sleeve cooling efficiency monitoring device has the dual functions of monitoring the cooling water flow and the tuyere temperature in real time, accurately detects the flow speed of a pipeline through the built-in turbine flowmeter, and realizes dynamic visual monitoring of the cooling efficiency of key parts of the blast furnace tuyere sleeve in cooperation with the rotatable digital display screen.

The utility model relates to an adjustable air supply device bend support, which comprises a nozzle, a spray pipe seat and a bend body, an auxiliary support component is arranged at the bottom of the spray pipe seat, a mounting plate is arranged at the bottom of the auxiliary support component, a connecting plate is arranged on the outer side of the bend body, and the connecting plate is connected with the spray pipe seat. Two lifting supporting assemblies are arranged between the connecting plate and the mounting plate, two mounting grooves are formed in the top of the mounting plate, parts of the two lifting supporting assemblies are mounted in the two mounting grooves correspondingly, and the auxiliary supporting assembly comprises a mounting base and a high-temperature alloy corrugated lining plate. Under the action of the alloy lifting frames on the left side and the right side of the bent pipe body, the connecting plate on the outer side of the bent pipe body can be supported, and under the action of the high-temperature alloy corrugated lining plate, the impact influence of high-pressure airflow and high-speed airflow entering the bent pipe body is reduced, and the sealing performance of the connecting portion of the bent pipe body and a spray pipe base is guaranteed.

The utility model provides a special tool suitable for blast furnace fast opening tuyere, including steel fiber, be provided with the beat tray on the outside wall of steel fiber, the outside wall of steel fiber is slidably sleeved with slide hammer, slide hammer sets up in beat tray far from steel drill tip one side, slide hammer is along the axial of steel fiber and is towards beat tray one side slide and hits beat tray, the reaction force that utilizes slide hammer hits generates drive steel fiber to the tip direction movement to open blast furnace tuyere, the utility model discloses a slide hammer along the steel fiber / steel pipe slide hits beat tray's design, replaces traditional many people cooperation mode, only needs 1-2 people to complete operation, saves manpower and time, simultaneously, slide hammer slide hits impact force stability, high frequency, and the efficiency of opening tuyere is greatly improved.

A reducing gas injection system (10) for a blast furnace having a blast furnace wall (30), comprising: a reducing gas distribution pipe (20); and one or more injection devices (40) attached to the blast furnace wall at shaft level, wherein the reducing gas distribution pipe (20) is attached to the blast furnace wall (30) or a supporting structure thereof, and the injection devices (40) include a nozzle body (42) having a peripheral wall extending along a longitudinal axis from a front end having at least one injection hole (41) to an opposite rear end having an inlet (43), the nozzle body including an internal gas channel for directing reducing gas from the inlet (43) to the injection hole (41), and the nozzle body (42) is attached through an opening in the blast furnace wall (30) so that the front end having the injection hole (41) is located inside the blast furnace (31). a nozzle body (42) including a peripheral mounting portion configured to gas-tightly connect the injection device to the opening in the blast furnace wall, the nozzle body (42) including a peripheral mounting portion configured to gas-tightly connect the injection device to the opening in the blast furnace wall, the inlet (43) being fluidly connected to a reducing gas distribution pipe (20) by an injection device support, the injection device support including a supply pipe (51) connected to the reducing gas distribution pipe (20), an elbow (52) connected to the supply pipe (51), and an injection pipe (53) connected to the elbow (52), the injection pipe (53) being gas-tightly flanged to the inlet (43) of the injection device (40) and gas-tightly attached to the injection pipe (53) and / or an outlet of the elbow including at least one Cardan compensation joint (531).

The utility model discloses a blast-furnace tuyere small sleeve leakage detection device, which comprises a plurality of water return grooves fixedly arranged on a blast-furnace tuyere platform; a first joint of the tee joint is connected with a small sleeve water outlet pipeline, a second joint is connected with a small sleeve water return ball valve, and the small sleeve water return ball valve is connected with a furnace bottom medium-pressure water return main pipe; one end of the water tank is provided with a water inlet pipe, the other end of the water tank is provided with a water outlet pipe, the water inlet pipe is used for connecting a third connector of the tee joint, and the water outlet pipe is used for connecting a recovery tank; and the detection device is used for detecting whether gas discharged from the gas detection port contains carbon monoxide. The water inlet pipe is connected with the third connector of the tee joint, the water outlet pipe is connected with the water inlet in the water return groove, the water return ball valve is closed, the carbon monoxide detector is connected into the gas detection opening, then the small sleeve water inlet ball valve is slowly controlled, and therefore leakage detection can be rapidly conducted on the tuyere small sleeve on line, and whether the tuyere small sleeve is damaged or not can be accurately judged.

The invention discloses a short-term overhaul construction method for a blast furnace body. The method comprises the following steps: lowering the charge level of the blast furnace below the center line of a tuyere; damping down the blast furnace; removing the tuyere medium sleeve, the tuyere small sleeve and the furnace top large manhole; hoisting a row rake to level the charge level in the furnace; a covering agent is sprayed to cover the material surface in the furnace, and slag removal and danger removal are conducted on a furnace body; a cooling wall operation hanging scaffold is assembled on the surface of the covering agent; the cooling wall is replaced; cleaning the upper semicircles of the tuyere combined bricks; a cooling wall operation hanging scaffold serves as a construction platform to clean the surface of the cooling wall in the area above the tuyere, and wet spraying is conducted; a furnace throat steel brick protection plate is replaced; local repairing is conducted on the gas sealing cover spraying paint; removing a covering agent and a cooling wall operation hanging scaffold; performing synchronous construction outside the furnace; reassembling furnace top and tuyere equipment; the furnace body is pressed for leakage detection; and carrying out blast furnace charging and reblowing production. According to the short-term overhaul construction method for the blast furnace body, a systematic thought is provided for short-term overhaul of the blast furnace, the construction period required by short-term overhaul of the blast furnace can be shortened, and the shutdown loss is reduced.

The utility model discloses an elbow pressing and fastening device, which relates to the technical field of blast furnace ironmaking equipment and comprises a fin plate fixedly mounted on an elbow and a tension device with one end rotatably connected to a furnace shell and the other end clamped on the fin plate. A U-shaped bayonet is formed in the end, away from the bent pipe, of the fin plate, the tensioning device comprises a screw clamped in the U-shaped bayonet of the fin plate and a fastening mechanism in threaded connection with the screw, one end of the screw is rotationally connected with the furnace shell, the other end of the screw penetrates through the U-shaped bayonet of the fin plate to be provided with the fastening mechanism used for pressing the fin plate, and a return preventing structure is arranged on the fastening mechanism; the air inlet device has the advantages that the anti-return structure is arranged, loosening of the screwing nut caused by displacement deformation in a high-temperature environment is avoided, and air leakage at the sealing position of the front end of the air inlet device and the small tuyere sleeve is also avoided; and grease can be injected at regular intervals for lubrication and maintenance through the lubricating opening, so that the thread is smoother in the mounting and dismounting process, thread abrasion can be reduced while thread corrosion is avoided, the fastening effect is improved, and the service life is prolonged.

A new technology for suppressing bias in the radial distribution of reducing gas concentration inside a blast furnace when reducing gas is supplied into the interior of the blast furnace is disclosed. One embodiment of the technology disclosed herein is a blast furnace having a hot blast tuyere, the hot blast tuyere having a tuyere body, a reducing gas injection port, and a reducing gas injection lance, the tuyere body having a hot blast flow path, the reducing gas injection port penetrating a wall of the tuyere body, and the reducing gas injection lance having an outlet within the hot blast flow path.

The invention relates to the technical field of metallurgical engineering, and discloses a mixed coal injection, coal gun and blowpipe improvement process, which comprises the following steps: S1, designing and optimizing a coal blending structure, selecting high-volatility bituminous coal and low-volatility coal to mix and inject pulverized coal, dynamically adjusting the proportion according to the coal quality characteristics, and controlling the volatile component range of the pulverized coal to be 20-25%; s2, process parameters are adjusted, the temperature range of gas entering a mill is 260-280 DEG C, in the step S1, the initial proportion is 40%-50% of high-volatility bituminous coal and 50%-60% of low-volatility coal, and the proportion of the low-volatility coal is adjusted to 35%-40% in stages. By optimizing the coal blending structure, flexibly adjusting the proportion of the high-volatility bituminous coal to the semi-coke powder and controlling process parameters, the combustion efficiency and the injection amount of the pulverized coal are effectively improved, it is ensured that the pulverized coal can be combusted and utilized more sufficiently in the injection process, and the production efficiency is substantially improved.

The utility model discloses a blast furnace tuyere platform hoisting hole structure which comprises a through hole formed in a tuyere platform, a plurality of supporting plates and a step arranged on the through hole in a supporting mode, guardrails are fixedly installed in the circumferential direction of the through hole, and the guardrails comprise the left guardrail, the right guardrail, the front guardrail, the rear guardrail and the movable guardrail. A left guide rail is fixedly installed on the inner side of the left guardrail, a right guide rail is fixedly installed on the left side of the right guardrail, the left guide rail and the right guide rail are symmetrical, the left guide rail is an L-shaped piece, the L-shaped piece comprises a horizontal section and a vertical section fixedly connected with the horizontal section, the horizontal section is fixed to the left guardrail, and a groove is formed between the vertical section and the left guardrail. The left end and the right end of the movable guardrail are each fixedly provided with two fixing bases, and idler wheels are installed on the fixing bases and arranged in the grooves. Due to the existence of the movable guardrails, the operators can stand at the reserved supporting plates to assist in discharging due to edge protection, the problem that the operators pull and hoist obliquely is avoided, the working efficiency is improved, and potential safety hazards are avoided.

This invention relates to the field of pulverized coal distributor technology and discloses an intelligent uniform distribution blast furnace pulverized coal injection device, comprising: a conical distribution chamber, the distribution chamber including a lower cone and an upper cone cover detachably installed on the top of the lower cone, the bottom of the lower cone being fixedly connected to a pulverized coal supply pipe. This intelligent uniform distribution blast furnace pulverized coal injection device can achieve long-term stable uniform distribution and maintenance-free operation; by utilizing the rotating airflow formed by the built-in guiding element, the pulverized coal is fully mixed and evenly distributed within the chamber before being distributed, resulting in minimal deviation in the amount of pulverized coal at the outlet of each branch pipe, ensuring consistency in pulverized coal injection at all tuyeres. This is crucial for stable blast furnace operation, reducing fluctuations in furnace temperature and reducing atmosphere caused by uneven distribution, and the unique coarse particle settling tank design significantly improves anti-clogging performance: coarse particles and foreign matter are actively separated and collected, preventing them from entering the outlet pipe and avoiding the risk of blockage in the outlet pipe previously observed.

The application discloses a blast furnace pulverized coal electromagnetic preheating system and process and relates to the technical field of blast furnace ironmaking. The blast furnace pulverized coal electromagnetic preheating system comprises a pulverized coal bin, a blowing tank and a mixer. A radial flow guide device is arranged at the inlet end of a coarse preheating pipeline. The radial flow guide device is used for separating materials according to diameters and guiding the materials to move along the inner wall of the radial coarse preheating pipeline. A medium heating device is used for forming a heating channel and heating the materials moving along the middle part of the coarse preheating pipeline. A dispersing device is arranged at the outlet end of the coarse preheating pipeline. The dispersing device is used for dispersing materials with different particle sizes into different areas and conveying the materials into a fine preheating pipeline. The blast furnace pulverized coal electromagnetic preheating system and process remove the moisture of the powder through coarse preheating, guide the powder with different particle sizes to separate and move along the inner wall of the coarse preheating pipeline, disperse the materials with different particle sizes into different areas through fine preheating and make the powder reach the temperature close to the ignition point.

The invention discloses a modularized platform for building a blast furnace in a narrow space and a building method, an upper furnace body and a lower furnace body of the platform are composed of a plurality of furnace body modules and a plurality of furnace seat modules, the furnace body modules are connected with the furnace seat modules through connecting nails, the furnace seat modules are mounted above a base station, and the furnace seat modules are connected with the base station through connecting nails. And the furnace body module is arranged on the upper layer of the furnace seat module. The modular platform and the construction method have the beneficial effects that a worker can construct the blast furnace in a narrow space through the modular platform and the construction method, the blast furnace can be constructed only through construction of the furnace body module and the furnace base module, and the same strength and safety can be achieved after construction is completed; as the furnace body module and the furnace seat module can be industrially produced and manufactured, the construction cost and time of the blast furnace can be effectively reduced.

The injector(s) have a nozzle body with an inner gas channel for guiding reducing gas from an inlet port to injection holes(s). The nozzle body is mounted trough an aperture in the blast furnace wall at a shaft level of the blast furnace and includes a peripheral mounting portion configured for connecting the injector in a gas tight manner to the aperture. The inlet port is in fluidic connection with a reducing gas distribution pipe by means of an injector stock including a feeding pipe connected to the reducing gas distribution pipe, an elbow connected to the feeding pipe and an injector pipe connected to the elbow and being flange mounted in a gas tight manner to the inlet port. The injector pipe and / or an outlet of the elbow have at least one cardan compensation joint.

The utility model discloses an efficient energy-saving tuyere small sleeve with a composite protective layer on the outer surface for a blast furnace, and particularly relates to the technical field of blast furnace smelting equipment, which comprises a tuyere small sleeve body, and a plurality of lining ceramic composite pipes are arranged on the outer surface of the tuyere small sleeve body. The plurality of lining ceramic composite pipes are annularly and uniformly distributed on the outer surface of the tuyere small sleeve body; the lining ceramic composite pipe comprises a heat-resisting stainless steel outer wall layer, and a lining ceramic inner wall layer is arranged in the heat-resisting stainless steel outer wall layer. The lining ceramic composite pipe is arranged and covers most of the outer surface, extending into the blast furnace, of the tuyere small sleeve body, and the inner surface of the small sleeve almost covers the lining ceramic composite pipe, so that heat taken away by cooling water is reduced to the maximum extent, the water inlet and outlet temperature difference of the small sleeve is greatly reduced, and the service life of the tuyere small sleeve is prolonged. And moreover, the hot air temperature is increased in a disguised manner, the pulverized coal combustion is facilitated, a great amount of production consumption is saved for the blast furnace, and very considerable economic benefits are brought.

A new technology for suppressing bias in the radial distribution of reducing gas concentration inside a blast furnace when reducing gas is supplied into the interior of the blast furnace is disclosed. One embodiment of the technology disclosed herein is a blast furnace having a hot blast tuyere, the hot blast tuyere having a tuyere body, a reducing gas injection port, and a reducing gas injection lance, the tuyere body having a hot blast flow path, the reducing gas injection port penetrating a wall of the tuyere body, and the reducing gas injection lance having an outlet within the hot blast flow path.

The invention discloses a water-cooling-free tuyere suitable for blast furnace smelting and an air curtain control method.The water-cooling-free tuyere comprises a lining, an air curtain protection sleeve shell and an inner air curtain channel, the lining is wrapped by the air curtain protection sleeve shell, and the inner air curtain channel is formed in a gap between the lining and the air curtain protection sleeve shell; air curtain air of the water-cooling-free tuyere is taken from pipeline air in front of the hot blast stove and is supplied into the inner air curtain channel through an independent pipeline, and during the smelting, damping down and other periods of the blast furnace, the pressure of the inner air curtain channel, the air supply pressure and the pressure in the furnace are monitored in real time, and the opening degree of a control valve is adjusted in real time to control the pressure of the inner air curtain channel so as to maintain the stability of the air curtain. According to the method, the inner and outer air curtains are formed, the internal temperature difference of the tuyere lining is reduced, the supporting strength is maintained, the service life of the tuyere is prolonged, meanwhile, channel water flow cooling is omitted, the hot air charging temperature is increased, the characteristics of long service life and energy conservation are achieved, and the problems of high tuyere breakage rate and short service life in the blast furnace smelting process are fundamentally solved.

The invention belongs to the technical field of blast furnace smelting, and particularly discloses a blast furnace blow-in middle adjusting method which comprises the four steps of blow-in initial stage cooling schedule setting, middle stage cooling and tuyere cooperative adjustment, dynamic monitoring and emergency treatment and later stage stabilization and parameter callback. The problems of insufficient activity of the hearth, poor stability of the slag crust and unbalanced heat system are solved through the four steps, and after the technical problem is solved, the stability of the slag crust can be improved by 40%, and the heat loss is reduced by 3.5%; the coal gas utilization rate is increased to 44-45%, and the fuel ratio is reduced by 8-10 kg / t; the air volume is stabilized to 4500 m < 3 > / min, and the yield is recovered to 5000 t / d.