CN117683954A

CN117683954A - Safety environment protection method for blowing out extra-large blast furnace in favor of discharging clean residual iron

Info

Publication number: CN117683954A
Application number: CN202311702778.2A
Authority: CN
Inventors: 缪德明; 丁庆森
Original assignee: Shanghai Tuojiang Construction Engineering Co ltd
Current assignee: Shanghai Tuojiang Construction Engineering Co ltd
Priority date: 2023-12-12
Filing date: 2023-12-12
Publication date: 2024-03-12

Abstract

The invention relates to the technical field of blast furnaces, in particular to a safe and environment-friendly shutdown method of an oversized blast furnace which is favorable for discharging clean residual iron, comprising the following steps of: step 1: preparing before construction; step 2: preparing; step 3: iron residue discharging operation; step 4: cleaning a hearth; step 5: safety protection measures; step 6: controlling construction quality; step 7: the invention has the following beneficial effects: the method has the advantages of no discharge of the whole-process recovered gas, 2-6 meters above the center line of the tuyere, coke charging, hearth residual iron discharging and hearth cleaning, no large discharge valve at the furnace top, atmospheric pollution and noise disturbance during the furnace stopping process, simpler operation of the blast furnace, easy control, contribution to reducing the hearth residual iron amount, hearth residual iron discharging, realizing safe and rapid hearth cleaning, adopting sand to manufacture a residual iron pit, replacing refractory materials and reducing the cost.

Description

Safety environment protection method for blowing out extra-large blast furnace in favor of discharging clean residual iron

Technical Field

The invention relates to a safe and environment-friendly shutdown method of an oversized blast furnace, which is favorable for placing clean residual iron, and belongs to the technical field of blast furnaces.

Background

The traditional blast furnace blowing-out method has the advantages that the blast furnace top large diffusion valve is opened for safety, the environment is polluted by the non-dust-removed gas, noise of the diffusion valve disturbs people, mixed gas knocking easily occurs during the process of blowing water down the blast furnace top to a tuyere, unexpected safety accidents occur, operation influence factors are too many, the in-place control is difficult, the risk is high, and meanwhile, the blast furnace is overhauled, the residual iron amount is large, the residual iron is not purified, the cleaning speed of a hearth is slow, and the operation difficulty is large.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention aims to provide a safe and environment-friendly shutdown method of an oversized blast furnace which is favorable for discharging clean residual iron so as to solve the problems in the prior art.

In order to achieve the above object, the present invention is realized by the following technical scheme: the safe and environment-friendly shutdown method of the oversized blast furnace, which is favorable for discharging clean residual iron, comprises the following steps of:

step 1: preparing before construction;

step 2: preparation: the existing equipment and facilities on site are shifted, the iron notch is accurately positioned, the iron notch and the buffer pool are designed and installed, an iron platform is built for operation, the facilities are protected in a heat-insulating mode, the iron pit is designed and manufactured, resources required in a preparation working stage are prepared, and dangerous sources are identified in the preparation working stage;

Step 3: and (3) residual iron discharging operation: the method comprises the following steps of setting iron residues, safety confirmation before the iron residues are set, setting working hours of the iron residues, setting tools and tools for the iron residues, setting worker tissues of the iron residues, setting consumable materials for the iron residues, and setting dangerous sources of the iron residues for identification;

step 4: cleaning a hearth: cleaning and transporting residual iron blocks outside a furnace hearth, cleaning and transporting materials, refractory materials and iron blocks in the furnace, cleaning loose materials in the furnace, cleaning tuyere combined bricks, cleaning side wall carbon bricks, cleaning slag iron mixed with non-iron precipitation in the hearth like foot area and the furnace bottom, cleaning a large amount of residual iron in the furnace (plan), discharging residual iron, and cleaning tools for the furnace hearth;

step 5: safety protection measures: temporary electricity management measures at construction sites, high-rise operation safety management measures, fire operation safety management measures, hoisting safety management measures, gas area occupational safety management measures and emergency measures in special operation stages;

step 6: and (3) construction quality control: quality control key points and quality control measures;

step 7: environmental protection and civilized construction measures.

Specifically, in the step 1, protective measures are taken for the equipment and the components which enter the field, the unqualified construction materials strictly forbid the entering the field, and construction rest areas, tools and material stacking places are required to be set according to requirements; power sources such as practical electricity and the like; the tools and equipment which arrive at the site need to be arranged in place according to the requirements, so that the orderly penetration among the working procedures is ensured; the field is required to be provided with a distribution box, so that sufficient power supply is ensured, safety accessories of electric appliances are required to be intact, the welding machine shell is required to be grounded, and the conducting wires are required to be insulated well.

Specifically, in said step 2, the displacement of the field existing equipment facility: according to the existing equipment and pipeline arrangement condition of the blast furnace hearth and the direction of a railway, determining that a residual iron port is approximately positioned on a hearth cooling wall, implementing uncoupling of a cooling wall water pipe, redirecting the cooling wall water pipe, and freeing the position where the residual iron channel flows through, and carrying out displacement or heat insulation protection measures on cables and a bridge of an electric valve of a dedusting pipeline at the hearth part, wherein some small impurity pipelines of the hearth are displaced;

accurate positioning of the scrap iron: outside the furnace shell, the boundary of the cooling wall is marked clearly by using obvious paint or stone pens, the position which is more than 150mm away from the boundary line and is in the boundary line of the cooling wall is marked as the outer line of the mud sleeve frame of the iron notch, the positioning line of the iron residue platform is set up according to the position of the mud sleeve frame, and the elevation of the position to be drilled on the carbon brick is determined according to the positioning line of the iron residue platform and the drilling interval position of a three-hole two-drilling method;

design and installation of a residual iron runner and a buffer keeper: cross-sectional shape of the main scrap iron channel: the steel shell is made into a trapezoid section with a large upper part and a small lower part, the width of an upper opening is 1200mm, the width of a lower opening is 600mm, the height of the lower opening is 800mm, the buffer reservoir is a steel container with a length and a width of 2000mm and a height of 1200-1500mm, the steel container can be finely adjusted according to the actual conditions on site, refractory bricks are padded on the inner bottom layer, and then the thickness of refractory materials on the bottom surface is larger than 600mm;

Constructing a residual iron platform: constructing a residual iron operation platform, wherein the width of the residual iron platform is more than 3.5 meters, the length of the residual iron platform is more than 6 meters, and the height of the residual iron platform is more than 2 meters in principle, and the residual iron platform is limited by field conditions and needs to be finely adjusted;

manufacturing a main iron runner on an iron residue platform, wherein the main iron runner is opposite to an iron residue hole, determining the size of a frame of a tapping hole according to the position of the iron residue hole and the position of a beam on site, welding a bottom plate of the main runner of the tapping hole at the lower edge of a mud sleeve frame of the tapping hole at 50-300mm, performing fine adjustment according to specific conditions on site, fully welding a steel plate of the main runner of the tapping hole and a furnace shell, paving thick yellow sand with more than 200mm below the iron residue platform, paving a spacer bracket at the position of 100mm away from a beam on the right above the iron residue platform, welding the spacer bracket by angle steel, or paving a spacer bracket by using a building frame pipe, paving a pattern plate with 3mm thick on the bracket, paving water slag or yellow sand with 50-100mm thick on the pattern plate for heat insulation, protecting the beam, thickening the boundary of a cooling wall by paint, marking clearly, and only allowing to break a cooling wall and a corresponding furnace shell when manufacturing the tapping hole, and performing a 2-3 personnel evacuation safety channel construction on the two sides of the maximum area of the iron residue platform and the main runner according to the site conditions;

and (3) heat insulation protection of facilities: the method is characterized in that a beam above the residual iron platform, a water pipe above a residual iron hole, the ground below the residual iron platform, side walls, an upright post in an iron sinking pit area and the like are all required to be protected in a heat insulation mode, the upright post adopts surrounding bricks to fill yellow sand or is bound by using water slag cotton, a residual iron groove flows through the ground and below the residual iron platform, the yellow sand is paved with 200mm thick, the yellow sand is paved as much as possible near the side of a blast furnace, the upper surface of the yellow sand is higher near the side of the blast furnace, the side of the iron sinking pit is slightly lower, the situation that the bottom of the residual iron platform is as much as possible is achieved according to the field condition, even if the residual iron groove is full of sticky iron, the residual iron can flow into the iron sinking pit through the ground, therefore, the yellow sand needs to be used for compacting and paving-a ground emergency diversion trench, and the safety risk caused by the falling of residual iron after the overflow of the residual iron is avoided, and the measure belongs to an emergency standby trench of the residual iron main trench;

Designing and manufacturing a submerged pit: the main materials used in the iron sinking pit are yellow sand containing about 8-10% of clay mud, refractory bricks and watercannon mud, the yellow sand containing 8-10% of mud is piled up, compressed and compacted, then the iron sinking pit is dug into two sections, the end of the railway line is the normal pit, the position close to the normal pit is the emergency standby pit towards the railway outlet end of the iron yard, when the iron sinking pit is manufactured, the steel upright post of the iron yard is well protected by the refractory materials, the wind-proof and rain-proof measures are carried out at the two ends of the iron sinking pit, the residual iron flows through the areas and facilities to be heat-insulating protection measures, the water slag cotton or fire brick, the yellow sand and the yellow sand are paved on the ground, the thickness is 50-100mm, the construction of the residual iron pit is divided into three parts, the operation of the main groove of the residual iron, the buffering operation and the branch groove operation, and the tamping, manufacturing and baking of the refractory materials in village: after the preparation is finished, the balanced wood is laid, and the baking is carried out for 1 to 2 days before the furnace is stopped, and the baking requirements are that: and the baking with small fire is balanced, so that the refractory material is prevented from cracking due to uneven heating, the surface of the baked refractory material is slightly reddish, cannot be over red or whitened, cannot be directly blown to be directly baked with oxygen, and otherwise, the refractory material is prevented from being excessively baked to crack.

Specifically, in the step 3, the operation of putting the residual iron is focused on: checking and confirming an iron residue placing condition system, namely rapidly cutting a furnace shell and a cooling wall mud sleeve mud frame by using high oxygen, measuring the temperature of a carbon brick, making a mud sleeve, tamping the carbon brick and a main ditch refractory material, baking the mud sleeve and the iron drop point refractory material for 1-2 hours until the surface of the refractory material turns red, drilling the iron residue by using a YT28 type rock drilling machine for one, two or three eyes, measuring the drilling temperature while drilling, determining which eye is used for discharging the iron residue after finding out the red point of the drilling, and because the condition of an iron residue placing operation site is limited, particularly the operation space is narrow, an operation platform cannot be built widely, a non-operator can not ban the operation platform for placing the iron residue on tightly, particularly after the red point appears in the iron residue eye, the operator can ban the operation platform to stand right, the operation in the main ditch is banned tightly, the two sides of the main ditch must be closed to a safety channel, the operation platform is controlled to operate the number of people to be less than 8, and after the last iron residue is discharged by the stop furnace, the operation platform is ready for manufacturing the iron residue opening; closing cooling wall water at the position of a scrap iron port in advance, cutting off a water pipe, blowing stored water by using compressed air, drawing boundary lines of a scrap iron port frame on a furnace shell, burning and cutting furnace skins and cooling walls at the position of the scrap iron port by using high oxygen, controlling the size to be 600 multiplied by 800mm, cutting and removing the furnace skins at the position of the scrap iron port by using high oxygen, burning the cooling walls, firstly burning red cooling walls, observing water outlets of the cooling walls, continuously blowing the water inlet and outlet pipes of the cooling walls by using the compressed air if a large amount of steam is emitted to indicate that the stored water is not blown out, cutting and cooling wall operation is needed to be stopped, digging and removing cold face ramming materials of carbon bricks after the cooling walls are burnt, measuring the surface temperature of the carbon bricks, if the surface temperature of the carbon bricks is lower than 150 ℃ to indicate that the thickness of the carbon bricks is higher than 800mm, otherwise indicating that the residual carbon bricks are thinner, adjusting the size and depth of drilling, paying attention to safety, ramming and paving a layer of refractory bricks at the bottom layer, the thickness of the mud sleeve is 75mm, the depth of the mud sleeve from the furnace skin is not less than 200mm, the thickness of the mud sleeve is not less than 300mm, timber is used for baking the refractory material around the iron notch, the mud sleeve is ensured to be dried, the mud sleeve is not suitable for baking by using gas fire, inflammable and explosive substances in the iron notch discharging area are all cleaned up in advance, the lowest drilling is firstly carried out at one eye, the drilling is stopped until red is seen, then two holes are drilled, the drilling is stopped until red is seen, finally three holes are drilled, the drilling is stopped until red is seen, according to the conditions of the three holes, the lowest iron notch which can possibly be discharged is taken as the main iron notch, the drilling is carried out again to directly drill through the iron notch, then the tail part of the drill rod is removed, if the drill rod is left in the iron notch channel, the tail part of the drill rod is burnt through by oxygen, when the iron notch is discharged, the residual iron is reduced, or the slag is discharged after the iron notch is cut off, the cold air is fed to a blast furnace through a blast furnace blower, the slag is discharged by slight positive pressure, the wind pressure is about 60-100kpa, which is favorable for the excessive discharge of residual iron.

Specifically, in said step 4, the hearth-external iron scrap pieces are cleaned and transported: removing and cleaning the residual iron blocks, residual iron ditches, diversion ditches, iron receiving pits, platform rails, refractory materials, sand materials and other facilities or sundries generated by the blast furnace residual iron discharge, transporting to a designated position area, estimating the distance to be about 150 meters, the normal iron-sinking block is mainly dumped by a forklift, and the reserved pit residual iron block is dumped or dumped after being cut by a rope after being cut at night;

cleaning and transporting materials, refractory materials and iron blocks in the furnace: the principle is that a slag skimming door is not arranged, materials in the furnace can be transported out of the furnace or a cast house from a tuyere (the diameter of a large sleeve mouth is 1048mm or the diameter of a medium sleeve mouth is 785 mm), a furnace top hoisting large square hole (2300 mm multiplied by 1800 mm), a taphole (1180 m multiplied by 880 mm) and other channels, and the cleaning of refractory materials and crushed coke slag in the furnace comprises 4 parts of operations: clearing loose materials above the air port, and mainly discharging by a belt; cleaning the tuyere combined bricks, wherein cleaning by a digging machine is mainly used, and manual cooperation is used as an auxiliary; cleaning 5-17 layers of carbon bricks on the side wall of the hearth, wherein the number of carbon bricks on the side wall is 1024, and each layer is 76 and 13 layers; cleaning slag iron mixed with slag precipitated by hearth elephant feet, and mainly using the operation of a separator;

Cleaning loose materials in a furnace: the loose material cleaning method comprises the following steps: constructing 1-2 belt conveyors at the air port, directly conveying loose materials into a transfer trolley from the furnace by the belt conveyors, operating the loose coke by using 1-8 diggers 3 meters above the center line of the air port in the furnace and 3 meters below the center line of the air port, and mounting a climbing belt after cleaning the loose coke to 3 meters below the center line of the air port; material cleaning above the center line of the tuyere: before the operation of entering the furnace, 4 positions of the furnace outer tuyere platform are required to be scraped into an air inlet and outlet channel, an escape ventilation channel air inlet, 4 in and 4 out and 4 in and 4 out, the total of 8 air inlets, the slope of the material surface in the scraping ventilation opening is less than or equal to 45 DEG, because the distance from the outer edge of the large-sized blast furnace air inlet to the coke is more than 1.5 meters, the manual scraping efficiency is low, only one micro-digging can be adopted for mainly, one micro-digging is filled into a manual trolley, the 4 trolley is configured to meet the continuous charging operation of the micro-digging, and the materials are manually pushed to the material platform of the air inlet platform through the trolley and poured into a transfer vehicle;

cleaning the tuyere combined bricks: removing all middle sleeves of the tuyere platform and removing 2 tuyere large sleeves, so that the residual part of the tuyere combined bricks in the furnace is broken and chiseled by a digging machine and then is divided into small blocks to be directly carried out from the respective middle sleeves;

Cleaning the side wall carbon bricks: mode one: 2 tuyere large sleeves are disassembled, 1 tuyere large sleeve is used for mounting a supporting roller groove with the width of 2 tons and 700 meters, a 2-meter long and wide operating platform is built in the tuyere large sleeve from the side wall of a tuyere outlet part, a 5 ton winch is mounted at the position of 48 meters of a large manhole platform elevation of the furnace top right above the operating platform, or a 5 ton electric hoist is hung above a large manhole and overhauled on a 20 ton hoist, a door plate clamp is hung on the 55 m electric hoist, after the carbon brick is clamped by the door plate clamp, 3 ton and 6 meter hanging strips are used for binding, and a hanger is lifted to the tuyere operating platform from the carbon brick position, rolls out of a furnace shell by utilizing the supporting roller groove and extends the supporting roller groove to directly enter a transfer trolley; mode two: firstly, utilizing loose materials above an air outlet of a belt conveyor, after removing the air outlet combined bricks, reserving a digging machine with the effective working height of 2.5 meters, enabling the air outlet center line to reach the iron outlet center line by 4.7 meters, enabling the difference of 2.2 meters to reach the iron outlet center line, removing 2.2 meters of carbon bricks above the opposite angles of the iron outlets, removing four layers of carbon bricks, removing one layer of about 37 blocks, and four layers of about 136 blocks, wherein 17 hours are needed for lifting out in a first mode, continuously digging out the corresponding 2 iron outlets after removing, installing carrier roller grooves for carbon bricks at one iron outlet, and discharging partial large slag blocks at one iron outlet, wherein one digging machine for carbon bricks in a furnace is used for continuously discharging the loose materials, and three digging machines are matched with the carbon bricks after discharging the loose materials, and the carbon bricks are required to be completely discharged in a first mode and a second mode; mode three: hanging the large side wall carbon bricks from the furnace top by using a hanging bucket, wherein each bucket is 10 tons, the hanging of the large side wall carbon bricks once needs 30 minutes and 2 hoppers for one hour, after hanging the large side wall carbon bricks from the furnace top, transferring the large side wall carbon bricks into a large bucket, hanging the large side wall carbon bricks from the ground by using a furnace top travelling crane, welding the hanging bucket into a hanging bucket with the width of 1.6 meters, the length of 2 meters and the height of 1.8 meters by using a steel plate with the thickness of 8mm, and hanging 6-9 carbon bricks from each bucket continuously and taking 3 days;

Cleaning non-iron precipitation mixed slag iron in hearth elephant foot region and hearth: mode one: after the lifting is carried out by using a jack, a normal counterweight 3-5 ton drop hammer is used, the size is increased to 20 meters, the drop hammer is crushed and separated, small blocks within 10 tons are separated from a large manhole hanging position on the furnace top, and the small blocks are pulled out of the furnace by paving a flat plate on a tap hole carrier roller; mode two: after the jack is used for jacking, a rock drill is used for drilling holes, a 1500-2500 ton separator is inserted for separation into small blocks within 10 tons, the small blocks are hung from the furnace top, and the small blocks are paved on a tap hole carrier roller and pulled out of the furnace; mode three: after the lifting by using a jack, grooving by using a water knife, separating into 10 tons of small blocks by using a 500 ton hydraulic jack, hanging the small blocks from the furnace top, and paving a flat plate on a tap hole carrier roller to pull the small blocks out of the furnace;

cleaning (pre-plan) of a large amount of residual iron in the furnace: if the residual iron is not smoothly placed, more residual iron remains in the furnace, whether the slag door is opened or not needs to be immediately determined, and the main basis of the determination is as follows: referring to the actual tapping and theoretical tapping difference in front of the furnace; experience judges that if the residual iron notch is in the final slag, no matter how many iron depositing pits are formed, the residual iron in the furnace can be basically clean; if the gas fire is emitted from the residual iron port by the micro positive pressure wind energy at the end stage, even if the residual iron port blows wind more than 2 meters, the residual iron on the surface of the fixed residual iron port can be thoroughly cleaned, and residues among loose coke are basically cleaned;

And (3) discharging residual iron: the method is characterized in that a 3.2 m wide and 4 m high discharging hole is formed at a tap hole and is mainly used, a large manhole at the top of a furnace is lifted out as an auxiliary material, a mechanically-opened slag removing door is used for discharging into 50 forklift trucks by using 2 60 diggers, the 250 diggers are matched with the 50 forklift for loading and transferring to the transfer trucks, main materials are all discharged from the discharging hole, otherwise, the slag removing door is not opened, the lifting of the top of the furnace is mainly used, and the discharging of an air port, the tap hole and a residual tap hole is mainly used as an auxiliary material.

Specifically, in the step 5, the temporary electricity management measure at the construction site: the installation, the dismantling and the maintenance of the temporary power utilization of the construction must be completed by electricians strictly according to technical operation rules; all electrical panel boxes, machine equipment and the like in the construction site are reliably grounded or protected by zero connection; all the distribution boxes are required to be orderly arranged, one machine, one gate and one insurance are implemented, one gate and multiple machines are strictly forbidden, and the switch is required to be provided with a leakage protector; the capacity of each level of distribution device is matched with the load, the structure form, the disc surface arrangement and the system wiring are standardized, and the moisture-prone and explosion-prone articles on the construction site are strictly managed and used according to the moisture-proof, explosion-proof and fireproof safety standards; the damaged wires and cables are forbidden, and the wires and cables in the use process must be covered by channel steel and the like, so that rolling and burning are prevented; the electric equipment is strictly grounded, and the resistance of the grounding wire is not more than 4Ω; the construction cable must be highly insulated; the rated action current of the leakage protector of the total distribution box is less than 250mA, the action time is less than 0.2s, the rated leakage action current of the leakage protector of the switch box is less than 30mA, the action time is less than 0.ls, the leakage protection of a wet place adopts a splash-proof product, and the rated leakage action current is less than 15mA;

High-rise operation safety management measures: all personnel working at high places must carry out safety technology education and surrendering, and all safety technology measures and personal protection articles are implemented; the tool and the structure of the climbing operation must be firm and reliable; the safety rope is installed and pulled in advance before construction, the safety of constructors is tied on the safety rope, the safety rope is firmly and reliably hung, the safety belt is required to be hung at a high position and a low position, and the construction can be carried out after the safety belt meets the requirement through inspection; the edge operation should be added with protective railings or other reliable measures; the suspending operation should have a firm stand and be provided with protective fences, railings or other safety facilities according to the specific situation; when various works perform vertical and vertical three-dimensional cross operation, the operation of the lower layer operation is not performed in the same vertical direction, the position of the lower layer operation is required to be beyond the radius of the possible falling range determined by the height of the upper layer, and a safety protection layer is required to be arranged when the falling range is not matched with the radius of the possible falling range; optimizing an operation method and a construction sequence, and inserting unsafe operation contents into construction when conditions are convenient so as to ensure safety;

fire operation safety management measures: the worker keeps the guard on duty, and the labor protection articles are worn well; the oxygen and acetylene bottles are placed separately according to related regulations, and the interval is within a specified range; the oxygen and acetylene bottle cannot be placed under the ignition point, and the oxygen and acetylene bottle is correctly used according to relevant regulations; when the fire works, the fire-fighting evidence is needed to be done, inflammables are cleaned in time below the fire-fighting point, a fire extinguisher is prepared up and down, special people need to monitor the fire in the up and down process, and special people need to manage the oxygen and acetylene bottles; the parts of the field pipeline and the components to be welded are the segmented positions of the pipeline and the components;

Lifting safety management measures: the commander must support the guard and go on the job, should be familiar with the construction operation flow, use the explicit command signal to command, the personnel attending the operation should obey the command, if find out the command signal is unclear or have mistake, should stop the operation, go on after the contact is clear; the range of the operation area needs to be provided with obvious warning marks, and a person forbidden to stand under the suspended object; during hoisting, the operation should be performed as slowly as possible to reduce the impact of impact force and avoid overload and inclined hoisting components as much as possible; all lifting tools should be checked regularly, damaged parts are identified, and sling binding should be correct and firm; the endurance of the standing position of the field crane meets the construction requirement;

occupational safety management measures of a coal gas area: the carbon monoxide content of the gas area operation should not exceed 25PPm, can operate for a long time, but should make precautionary measures; when personnel participating in maintenance work need to pass through the safety bottoming, make self-precaution measures, carry a CO detector and prepare an air respirator, the personnel should work cooperatively at more than two people and stand up the wind place, the personnel are prohibited from individually entering the gas area for operation, and special personnel are arranged for monitoring during the operation; when the gas is constructed in a gas area, the carbon monoxide content is detected, and after the carbon monoxide content is detected to be qualified, the gas can be used in the gas area, constructors must wear a gas detector, the constructors hold a gas license, a full-time guardian is arranged, and when the carbon monoxide content is not more than 25ppm, the gas can work for a long time; when the carbon monoxide content is not more than 50ppm, the continuous working time in the process is not more than 1 hour; when the PPm exceeds 50PPm, the operation of wearing an air respirator is needed; when the gas area works, a safety warning sign is set up, a red and white rope loop is used for warning, and after the work is finished, the gas area is immediately evacuated, and the gas area cannot stay or rest; the gas area uses an explosion-proof safety lighting lamp; the confirmation time is confirmed 30 minutes before operation, the gas content is lower than 24PPm, and a gas detector is provided; confirming that the precautionary measures, guardians and warning measures are in place, prohibiting non-operation personnel from entering, and rapidly evacuating personnel in the field under abnormal conditions to ensure the smoothness of the escape channel.

Specifically, in the step 6, the quality control point is: the steel member and the refractory material are subjected to quality inspection after entering the site so as to confirm whether deformation, damage and defect exist in the transportation process and are timely processed by related departments; the construction team should check whether the geometric dimension, pitch, etc. of the components meet the regulations before installation, and should report to the relevant departments after the problems are found, in principle, the construction team must finish the treatment before installation; the management of the welding process is responsible for the arrival of people and falls to the actual place; the assembly is carried out according to the requirement, and the size is strictly controlled.

Specifically, in the step 7, environmental protection and civilized construction measures are taken: the environmental protection management system and related environmental protection regulations of iron works are executed in construction, the environmental protection education is carried out before construction, the incineration of asphalt, asphalt felt, rubber, garbage and other toxic substances generating malodorous gases are forbidden, the emission or leakage of toxic and harmful gases, liquid, dust and harmful gases are forbidden, the protection measures such as sealing are needed in the process of loading, unloading and transporting, the blowing of dust and high-level dust accumulation by compressed air is forbidden, the throwing and dust raising are forbidden, the dust raising prevention measures are needed in construction, the detached groove waste in construction is stored according to the appointed place, no sundries are needed to be randomly piled and placed, any sundries are needed to be piled on the construction site, the on-site civilized construction is needed, the project construction is completed, and the three-clean returning is needed.

The invention has the beneficial effects that:

the method has the advantages of no discharge of the whole-process recovered gas, 2-6 meters above the center line of the tuyere, coke charging, hearth residual iron discharging and hearth cleaning, no large discharge valve at the furnace top, atmospheric pollution and noise disturbance during the furnace stopping process, simpler operation of the blast furnace, easy control, contribution to reducing the hearth residual iron amount, hearth residual iron discharging, realizing safe and rapid hearth cleaning, adopting sand to manufacture a residual iron pit, replacing refractory materials and reducing the cost.

Detailed Description

The invention is further described in connection with the following detailed description, in order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the invention easy to understand.

The invention provides a technical scheme that: the safe and environment-friendly shutdown method of the oversized blast furnace, which is favorable for discharging clean residual iron, comprises the following steps of:

step 1: preparing before construction;

step 7: environmental protection and civilized construction measures.

In the step 1, relevant procedures required by the entering construction are required to be processed before the construction, and the stacking of construction tools and materials and the site construction preparation work are required; according to the drawing and the on-site investigation, a detailed construction scheme and a progress plan are compiled, so that the method is practical, safe and reliable; the number of operators, various construction tools, auxiliary facilities and the like entering the site is large, the allocation and management work of the operators are finished, and the operators can enter the site for construction; when the preparation work is performed in advance, the construction environment needs to be confirmed, and the safety construction of constructors is ensured; taking protective measures for the equipment and the components which enter the field, strictly forbidden by unqualified construction materials, and setting a construction rest area, tools and material stacking places according to requirements; power sources such as practical electricity and the like; the tools and equipment which arrive at the site need to be arranged in place according to the requirements, so that the orderly penetration among the working procedures is ensured; preparing and checking the machine tool before construction; the distribution box is required to be equipped on site, so that sufficient power supply is ensured, safety accessories of electric appliances are required to be intact, the shell of the welding machine is required to be grounded, and the conducting wire is required to be insulated well; engineering vehicles and crane slings required for construction must meet the requirements of site safety management, and legal compliance of running and parking is required; all operators on site have special operations, must be on duty for evidence, the validity, compliance and authenticity of the certificates are ensured, and all operators need to be trained through security education.

In step 2, the shift of the field existing equipment facility: according to the existing equipment and pipeline arrangement condition of the blast furnace hearth and the direction of a railway, determining that a residual iron port is approximately positioned on a hearth cooling wall, implementing uncoupling of a cooling wall water pipe, redirecting the cooling wall water pipe, and freeing the position where the residual iron channel flows through, and carrying out displacement or heat insulation protection measures on cables and a bridge of an electric valve of a dedusting pipeline at the hearth part, wherein some small impurity pipelines of the hearth are displaced;

accurate positioning of the scrap iron: the boundary of the cooling wall is marked clearly by using obvious paint or stone pens outside the furnace shell, the position which is more than 150mm away from the boundary line and is in the boundary line of the cooling wall is marked as the outer line of a mud sleeve frame of a residual iron opening, the positioning line of the residual iron platform is set up according to the position of the mud sleeve frame, the elevation of the position to be drilled on a carbon brick is determined according to the positioning line of the residual iron platform and the drilling interval position of a three-hole two-drilling method, the cutting openings of the furnace shell and the cooling wall are approximately rectangular, the height is 800mm, the width is 600mm, a residual iron frame is formed, the left part, the right part and the lower part of the residual iron frame are required to be compacted into a U-shaped mud sleeve by using cement cannon, and the thickness of the mud sleeve and the bottom of the residual iron ditch is about 350mm;

design and installation of a residual iron runner and a buffer keeper: cross-sectional shape of the main scrap iron channel: the steel shell is made into a trapezoid section with a large upper part and a small lower part, the width of an upper opening is 1200mm, the width of a lower opening is 600mm, the height is 800mm, the buffer reservoir is 2000mm long and wide, steel with the height of 1200-1500mm can be finely adjusted according to the actual conditions on site, refractory materials are rammed after refractory bricks are paved on the inner bottom layer, the thickness of a bottom surface refractory material is more than 600mm, when the steel shell is actually manufactured, the steel shell is measured on site, if the gradient of a main residual iron runner is less than 22 degrees, the main residual iron runner firstly enters the buffer reservoir, then flows into a branch runner from the buffer reservoir, if the gradient of the main residual iron runner is more than or equal to 22 degrees, the molten iron flowing speed is faster, the buffer reservoir is not suitable to be arranged in the half middle of the residual iron runner, and the buffer reservoir is considered to be arranged on the ground near the edge of a submerged iron pit;

Constructing a residual iron platform: building a residual iron operation platform, wherein the width of the residual iron platform is more than 3.5 meters, the length of the residual iron platform is more than 6 meters, and the height of the residual iron platform is more than 2 meters in principle, and when the residual iron operation platform is limited by field conditions and needs to be finely tuned, the residual iron platform has the bearing requirement: the width of the upper opening of the main residual iron ditch is 1200mm, the width of the lower opening is 600mm, the height is 800mm, the ditch length of 1.2 m multiplied by 6 m multiplied by 7 (iron density) = 60.48 tons, the volume of the ramming resistant material is deducted to be 1.2 multiplied by 0.45 multiplied by 6 multiplied by 7= 22.68 tons, 60-22=38 tons, the total of 10 persons per ton of the standing person and the maximum 30 persons per ton of the standing person is 3 tons, the weight of the resistant material is 1.2 multiplied by 0.45 multiplied by 6 multiplied by 2.3=8 tons, the bearing requirement of a residual iron platform is more than or equal to 38+3+8=50 tons, and the installation bearing is more than or equal to 50 tons for building;

manufacturing a main iron runner on an iron residue platform, wherein the main iron runner is opposite to an iron residue hole, determining the size of a box frame for placing the iron residue according to the position of the iron residue hole and the position of a beam on site, preliminarily determining to manufacture a rectangular box frame for placing the iron residue hole with the height of 800mm multiplied by 600mm, welding a bottom plate of the main iron residue runner along the lower edge of the box frame for placing the iron residue hole with 50-300mm, fine-tuning according to specific conditions on site, fully welding a steel plate of the main iron residue runner with a furnace shell, laying yellow sand with the thickness of more than 200mm under the iron residue platform, laying a interlayer bracket with angle steel at the position of 100mm away from a beam on site, or using a building frame pipe to build an interlayer bracket, laying a 3mm thick pattern plate on the bracket, laying 50-100mm thick water slag or yellow sand on the pattern plate for heat insulation, so as to protect the beam, and clearly marking the boundary of a cooling wall with paint, and only allowing to destroy a cooling wall and a corresponding furnace shell when manufacturing the iron residue hole, and taking a maximum area to build a safe passage for 2-3 persons who leave the iron residue main runner according to site conditions;

designing and manufacturing a submerged pit: the main materials used in the iron sinking pit are yellow sand containing about 8-10% of clay mud, refractory bricks and watercannon mud, the yellow sand containing 8-10% of clay mud is piled up, compressed and compacted, then the iron sinking pit is dug into two sections, the normal pit which is closest to the tail end of a railway line is formed, the emergency standby pit is arranged close to the normal pit towards the railway outlet end of a cast house, the normal pit size is 1.2 meters long, the width is 1.8 meters, the height is 0.6-0.8 meter, each pit can hold 8-11 tons of iron, some shapes are formed into long pits with the width of 0.4-0.8 meter, the length of 6 meters and the partition of every 2 meters, the size of the standby pit mouth is 10 meters, the length of each pit is 6-12 meters, the height of each pit is about 0.6-0.8 meter, the partition is added in the middle, the total iron capacity is prepared according to the maximum iron capacity of 3064 tons, and the iron capacity of each iron sinking pit is calculated according to the following steps: calculating the residual iron: the elevation of the central line of the iron notch is 1200mm, the hearth diameter is 14200mm, the dead iron layer thickness is 3200mm, the charging method is used for stopping the furnace after the iron surface is 1.2-1.5 m below the central line of the iron notch, the residual iron thickness is about 2000mm, the residual iron amount is 1=3.14/4×14.2×14.2×3.2×7.0=3545, the volume of the falling iron surface is not considered, the residual iron amount is 2=3.14/4×14.2×14.2×2×7.0=2216, the residual iron amount is 1060-2127 tons after the coefficient is 0.3-0.6, the charging method is used for stopping the furnace, the residual iron amount is about 730-1260 tons, and the area required by the iron sinking pit is calculated: the weight of molten iron is 1060/151 cubic meters/the depth of a submerged pit is 0.6 meters/the effective volume is 0.5=503 square meters, the normal submerged pit is manufactured according to the width of 10 meters and the length of 50 meters, the normal submerged pit is feasible, one side of the normal submerged pit is high and one side is low, the height difference is 1.2-1.6 meters, one side of the standby pit is low, the height difference is 0.5 meters, the length of the standby pit is 25 meters, the width is 11.9 meters, the area 296 square meters, 90% utilization area=267 square meters, 267 x 1 x 7=1869 tons, the normal submerged pit and the emergency standby pit=1246+1869=3115 tons are larger than 3064 tons, when the submerged pit is manufactured, the steel upright post of a cast house is protected, wind-proof and rain-proof measures are made at the two ends of the submerged pit, heat-proof and rain-proof measures are made in areas and facilities, water slag cotton or fire bricks, yellow sand and ground bedding yellow sand are made, the thickness is 50-100mm, three parts of construction operations of the residual iron pit are performed, a main iron pit, buffer operation, a buffer pit operation and a tamping operation, a tamping operation and a supporting operation, and a baking operation are made, and a stand material is baked: after the preparation is finished, the balanced wood is laid, and the baking is carried out for 1 to 2 days before the furnace is stopped, and the baking requirements are that: the baking with small fire is balanced, so that the cracking of the refractory material caused by uneven heating can be avoided, the surface of the baked refractory material is slightly reddish, cannot be over red or whitened, cannot be directly blown and directly baked with oxygen, and otherwise, the cracking of the refractory material caused by over baking can be avoided;

Resources required for the preparation working phase: the preparation stage comprises the following steps: ZX7-400D electric welding machine, cutting torch, gas alarm, oxygen detector, fire extinguisher, safety belt, lighting lamp, interphone, compressed air, chain block, forklift, crane, micro-digging and Fang Qiao; human resource arrangement in the preparation stage: a construction responsible person 2, responsible person on-site coordination, arrangement and other works; 2 people of the safety officer, each area overhauls the safety; 48 people, 16 people/class of the process group; ramming refractory materials to manufacture 16 persons and 8 persons/class; the welding bench worker builds a residual iron placing platform by 12 persons; 2, ensuring the power supply of field equipment; cleaning 2 persons in site in a sanitary way, wherein the time is 2 persons/8 hours; digging and repairing 16 persons, 8 persons/class; slightly digging 6 persons of a driver; 3 persons of forklift drivers; planning of main materials: the main channel 6m (10 mm thick steel plate: side wall 6×1×2=12 square meters, bottom surface 6×0.8=4.8 square meters, total 16.8 square meters, refractory plan 8 tons, use baking-free iron channel material); buffer dimensions 2m wide x 1.6m long x 1.2m high (8 mm thick steel plate: 2 x 1.2 x 2=4.8 square meters, 1.6 x 1.2 x 2=3.84 square meters, 1.6 x 2=3.2 square meters, total = 11.84 square meters, tolerance planning 4 tons); the predicted total length of the branch channel is 36m: bottom width 0.6m, side wall 0.8m, 36× (0.6+0.8+0.8) =79.2 square meter, tolerance planning 20 tons; total refractory planning=47 tons, 12-20 tons of blister mud, 1-2 tons of tap hole mud, 114×230 mm= 0.02622 square meters per area of standard T3 refractory bricks (specification size 230×114×65 mm), 0.0017043 cubic meters per volume=5725 cubic meters, total area 107.84 square meters, 4112 blocks, margin planning 4200 blocks, total volume= 7.158 cubic meters, 50% or more of T3 standard refractory brick A1203 content, 2.2 tons/m 3 volume, 16 tons of refractory bricks for planning, 530 square meters of total preplanned iron pit area, 800mm average thickness, and 200mm bedding bottom thickness;

Dangerous source identification in the preparation working stage: gas poisoning: the residual iron platform leaks coal gas, and counter measures are as follows: strictly forbidden irrelevant personnel enter and stay, confirm the condition of the blast furnace and the surrounding gas with the producer before construction operation, wear a gas detector and monitor by special personnel; scalding: molten iron spark sputtering, countermeasure: non-constructors can not enter, control the number of the operators of the operation platform, walk through the safety channel, and pass through the main ditch and the lower part of the swing chute under tapping, and transact fire evidence when using gas cutting electric welding, thus ensuring the work; electric shock: incorrect use of the power supply and the temporary electrical circuit are set up without compliance with regulatory requirements, countermeasures: checking and accepting before using the electricity facility, checking the circuit by full-time electricians every day, and checking the grounding qualification; falling: working at the edge of the platform, and countermeasures: the high-altitude operation is to hang a safety belt, and the cut platform railing is recovered in time or isolated by hard; transportation injury: and (3) pulling and transporting the yellow sand transport vehicle and the forklift, and preventing measures: whistling and personnel evacuation during transportation and transportation, commanding by special personnel, monitoring by special personnel during personnel operation, and leaving by the operating personnel during transportation; mechanical injury: when the miniature excavator operates, the bucket arm is unstable to control, and counter measures are taken: the special person commands, the micro excavator works, the operators withdraw, the construction is carried out after the excavator leaves and is confirmed by safety and the like, the working radius of the micro excavator is within 3 meters, the station person is forbidden, and the special commander uses the laser pen to command the work.

In step 3, the residual iron discharging operation is as follows: the blast furnace residual iron discharging operation comprises safe furnace stopping to-be-discharged residual iron operation instruction receiving, residual iron discharging operation preparation condition confirming, residual iron discharging area personnel evacuation confirming, special person monitoring of both sides of each pass-in and pass-out opening, warning line pulling, blast furnace cooling water leakage point water break, residual iron ditch, buffer pool, iron sinking pit baking inspection confirming, safe channel unblocking inspection confirming, inflammable and explosive object cleaning and leaving field, all pass-in confirmation of residual iron discharging operators and the like; the emphasis of the iron residue placing operation includes: checking and confirming a residual iron placing condition system, namely, rapidly cutting a furnace shell and a cooling wall mud sleeve mud frame through high oxygen, measuring the temperature of a carbon brick, making a mud sleeve, tamping the carbon brick and a main ditch refractory material, baking the mud sleeve and the iron drop point refractory material for 1-2 hours until the surface of the refractory material is red, drilling residual iron by using a YT28 type rock drilling machine, measuring drilling temperature while drilling, determining which hole is used for discharging residual iron after the drilling is red, and because the residual iron placing operation site condition is limited, particularly the operation space is narrow, an operation platform cannot be built widely, a non-operator can not ban the residual iron placing operation platform, particularly after red spots appear in the residual iron eyes, the operator can ban the operation platform to stand right, the operation in the main ditch is banned strictly, two sides of the main ditch must be close to a safety channel, the operation number of the operation platform is controlled to be less than 8, after the last iron is discharged from the stop furnace, the preparation of the residual iron hole is started, and all operators wear clean labor protection articles are prepared: the high-oxygen cutting technician wears the mask and the heat-insulating apron, and the construction operator mobile phone, the communication equipment and other traffic field logistics and safekeeping are forbidden, and the communication equipment, particularly the lithium battery communication equipment, cannot be observed beyond line; closing cooling wall water at the position of a scrap iron port in advance, cutting off a water pipe, blowing stored water by using compressed air, drawing boundary lines of a scrap iron port frame on a furnace shell, burning and cutting furnace skins and cooling walls at the position of the scrap iron port by using high oxygen, controlling the size to be 600 multiplied by 800mm, cutting and removing the furnace skins at the position of the scrap iron port by using high oxygen, burning the cooling walls, firstly burning red cooling walls, observing water outlets of the cooling walls, continuously blowing the water inlet and outlet pipes of the cooling walls by using the compressed air if a large amount of steam is emitted to indicate that the stored water is not blown out, cutting and cooling walls, digging and removing cold face ramming materials of carbon bricks after the cooling walls are burnt, measuring the surface temperature of the carbon bricks, if the surface temperature of the carbon bricks is lower than 150 ℃ to indicate that the thickness of the carbon bricks is more than 800mm, otherwise indicating that the residual carbon bricks are thinner, if the thickness of the carbon bricks are obviously reduced, adjusting the size and depth of drilling, taking care, ramming a slurry sleeve of the scrap iron port, paving a layer on a bottom layer, and thickness of the refractory bricks of 75mm, the depth of the mud sleeve from the furnace skin is not less than 200mm, the thickness of the mud sleeve is not less than 300mm, timber is used for baking the refractory material around the iron notch, the mud sleeve is ensured to be dried, the mud sleeve is not suitable for baking by using gas fire, inflammable and explosive substances and the like in an iron notch discharging area are completely cleaned in advance, the iron notch is drilled, the angle of the iron notch is upwards 8-15 degrees, the drilling is properly measured at 10 degrees, an outer-large-inner-small four-stage drilling method is adopted, the diameters of the drill bits are phi 60, phi 55, phi 50 and phi 45mm respectively, the drilling depth of each size is ensured to be not less than 500mm according to the surface temperature of a carbon brick, experience is summarized for many times, the problem that the iron flow of the iron notch is too far sprayed is not caused in an outer-large-inner small drilling channel, the normal distance of the iron flow of the iron notch is 300-500mm, the thickness of the cooling wall and the furnace shell are exactly avoided, and the iron notch is prevented from being sprayed when the iron notch is discharged when the iron notch is 2-level drilled, if the thickness of the carbon brick exceeds 800mm, the method comprises the steps of flushing and pulling an iron passing channel, when a residual iron hole is drilled, firstly drilling the lowest hole, stopping drilling until the hole is red, drilling two holes, stopping drilling until the hole is red, finally drilling three holes, stopping drilling until the hole is red, taking the lowest residual iron hole which can be tapped as a main residual iron hole according to the conditions of the three holes, directly drilling through the residual iron hole when drilling again, dismantling the tail part of a drill rod, if the drill rod is left in the residual iron channel, burning through by oxygen, when the residual iron is reduced at the end of tapping, or tapping after the residual iron is cut off, feeding cold air to a blast furnace through a blast furnace blower, carrying out slag with micro-positive pressure, wherein the wind pressure is about 60-100kpa, thereby being beneficial to the excessive tapping of the residual iron, ensuring that special people need to monitor, command and transfer information in the residual iron tapping process, and staff need to stand at safe positions, and idle staff are forbidden from entering in the residual iron tapping area;

Safety confirmation before the residual iron discharging operation: the confirmation content is as follows: to ensure that the information of the residual iron discharge operation instruction is smooth, the preparation condition of the residual iron discharge operation is confirmed, personnel in the residual iron discharge area is evacuated and confirmed, special personnel are arranged at both sides of each pass-in and pass-out port to monitor and pull up the warning line, the cooling water leakage point of the blast furnace is broken, the residual iron trench, the buffer tank and the iron sinking pit are baked and checked and confirmed, the safety channel is checked and confirmed smoothly, inflammable and explosive substances are cleaned and leave the site, and the personnel participating in the residual iron discharge operation all arrive at the post;

working hours of the residual iron discharging operation: the operation content is as follows: issuing a command of putting residual iron, and recording the issuing time; finally confirming the safety of the system before the residual iron is placed for 0.5 hour; a residual iron notch is welded with the furnace shell in a butt joint way for 2 hours; the cooling wall is disconnected and water is cut off for 1 hour; the compressed air sweeps the water in the cooling wall for 0.5 hour; high oxygen cutting furnace shell for 2 hours; high oxygen cutting the cooling wall in the corresponding frame for 2 hours; cleaning the mud sleeve frame, burning and dropping slag iron for 2 hours; making a mud sleeve, and tamping the refractory material for 1 hour; baking the mud sleeve, ramming the refractory material for 1 hour; 4-level drill at a glance: primary drill, large drill (60 drill bit), 0.2 hours; secondary drill, large drill (55 drill bit), 0.2 hours; three-stage drilling and middle drilling (50 drill bits) for 0.2 hour; four-stage drill, small drill (45 bit), 0.2 hours; two-hole 4-stage drill: primary drill, large drill (60 drill bit), 0.2 hours; secondary drill, large drill (55 drill bit), 0.2 hours; three-stage drilling and middle drilling (50 drill bits) for 0.2 hour; four-stage drill, small drill (45 bit), 0.2 hours; three-hole 4-stage drill: primary drill, large drill (60 drill bit), 0.2 hours; secondary drill, large drill (55 drill bit), 0.2 hours; three-stage drilling and middle drilling (50 drill bits) for 0.2 hour; four-stage drill, small drill (45 bit), 0.2 hours;

The residual iron discharging operation is configured as tools: ZX7-400D electric welder, cutting torch, gas alarm, oxygen detector, fire extinguisher, safety belt, interphone, gun head, square spade, JB100 type tamper, 50 type tamper, YT28 type rock drill, 5 meter drill rod, 4.5 meter drill rod, 4 meter drill rod, 3 meter drill rod, 2 meter drill rod;

the worker organization of iron residue discharging: a construction responsible person 3, responsible person on-site coordination, arrangement and other works; 6 people of the safety officer, each area overhauls the safety; 36 people and 12 people/class of process operation; 4, ensuring the power supply and illumination of the field device; 6, welder; on-site sanitary cleaning for 4 people and 2 people/8 hours;

consumable material for iron scrap discharging operation: 5 cubic meters of special yellow sand in front of a furnace, 1 ton of special mud sleeve mud for a tap hole, 3 tons of miscellaneous rotted wood, 2 tons of bubble mud, 20 blocks of fire bricks and 5 tons of D12 oxygen blowing pipes;

identifying a dangerous source of iron residue discharge: gas poisoning: the coal gas leaks from the bottom of the furnace, and the coal gas floats in the outer area, so that precautions are taken: the person is prohibited from staying, the unrelated person is prohibited from entering, the gas detector is worn, and the special person monitors; electric shock: incorrect use of the power supply and the temporary electrical circuit are set up without compliance with regulatory requirements, countermeasures: checking and accepting before using the electricity facility, checking the circuit by full-time electricians every day, and checking the grounding qualification; mechanical injury: when the rock drill is operated, the drill rod is damaged in a rotating way, and counter measures are taken: the special person commands, the rock drilling starts operation, and the forbidden operation personnel hold the drill rod by hand, take the horizontal pole contact drill rod, and the professional operator grasps the gas switch, discovers that the people contact the drill rod in time cuts off the gas and reminds.

In step 4, the hearth outer residual iron block is cleaned and transported: removing and cleaning the residual iron blocks, residual iron ditches, diversion ditches, iron receiving pits, platform rails, refractory materials, sand materials and other facilities or sundries generated by the blast furnace residual iron discharge, transporting to a designated position area, estimating the distance to be about 150 meters, the normal iron-sinking block is mainly dumped by a forklift, and the reserved pit residual iron block is dumped or dumped after being cut by a rope after being cut at night;

Cleaning loose materials in a furnace: theoretical calculation of loose material cleaning time: bulk material is about 3.14×7.1×7.1×11 m=1757 square m, the bucket volume of the 35-type excavator is 0.2 cubic m, the bucket volume of the shovel loose coke is 3 buckets per minute, 0.6 cubic m per minute, 3-type excavator is 1.8 cubic m per minute, 1757/1.8=976 minutes is needed for all bulk material discharging, 976/60=16 hours is needed for all bulk material discharging, the labor efficiency is calculated according to one third of continuous operation, and about 48 hours is needed for all bulk material discharging; the loose material cleaning method comprises the following steps: constructing 1-2 belt conveyors at the air port, directly conveying loose materials into a transfer trolley from the furnace by the belt conveyors, operating the loose coke by using 1-8 diggers 3 meters above the center line of the air port in the furnace and 3 meters below the center line of the air port, and mounting a climbing belt after cleaning the loose coke to 3 meters below the center line of the air port; material cleaning above the center line of the tuyere: before the operation in the furnace is not entered, 4 positions of the furnace outer tuyere platform are required to be scraped into an air inlet and outlet channel air inlet, an escape ventilation channel air inlet, 4 in and 4 out and 4 in, 8 air inlets are added, the slope of the material surface in the scraping ventilation opening is less than or equal to 45 degrees, because the distance from the outer edge of the large-sized blast furnace air inlet to the coke is more than 1.5 meters, the efficiency of manual scraping is low, only one micro-digging can be adopted for mainly scraping, one micro-digging is filled into a manual trolley, the 4 trolley is configured to meet the continuous charging operation of the micro-digging, the materials are manually pushed to the material platform of the air inlet platform through the trolley and poured into a transfer vehicle, and the theoretical calculation basis of the material cleaning above the air inlet is shown: 3 meters above the center line of the tuyere, 7.1×7.1×3.14×3=475 cubic meters, 475/38×8=100 cubic meters, the manual cleaning coke amount is about 100 cubic meters, and each tuyere outputs 12.5 cubic meters;

And (3) discharging residual iron: taking a 3.2 m wide and 4m high discharging hole at a tap hole as a main part, taking a furnace top big manhole as an auxiliary part, mechanically opening a slag removing gate, discharging into a 50 forklift by using 2 60 diggers in the furnace, loading and transferring the 250 diggers to a transfer trolley by matching with the 50 forklift, and discharging all main materials from the discharging hole, or else, not opening the slag removing gate, taking furnace top lifting as a main part, and taking a tuyere, a tap hole and a residual tap hole as auxiliary parts;

tool for cleaning hearth: ZX7-400D electric welding machine, cutting torch, gas alarm, oxygen detector, fire extinguisher, safety belt, intercom, gun head, square spade, 15-18 miniature digger, 30-60 type digger, 500 type belt conveyor, 1500 ton separator, YT28 rock drill, 1.2 meter drill pipe, 0.8 meter drill pipe, GT10-15 type pneumatic pick, 50 type forklift.

In step 5, temporary electricity management measures at the construction site: the installation, the dismantling and the maintenance of the temporary power utilization of the construction must be completed by electricians strictly according to technical operation rules; all electrical panel boxes, machine equipment and the like in the construction site are reliably grounded or protected by zero connection; all the distribution boxes are required to be orderly arranged, one machine, one gate and one insurance are implemented, one gate and multiple machines are strictly forbidden, and the switch is required to be provided with a leakage protector; the capacity of each level of distribution device is matched with the load, the structure form, the disc surface arrangement and the system wiring are standardized, and the moisture-prone and explosion-prone articles on the construction site are strictly managed and used according to the moisture-proof, explosion-proof and fireproof safety standards; the field application Wang Yong is executed strictly according to relevant regulations, and special person monitoring is set; the damaged wires and cables are forbidden, and the wires and cables in the use process must be covered by channel steel and the like, so that rolling and burning are prevented; the electric equipment is strictly grounded, and the resistance of the grounding wire is not more than 4Ω; the construction cable must be highly insulated; the construction electricity management is carried out by electricians who acquire the on duty card, the construction is carried out strictly according to the operation rules, no special reasons or protection measures are needed, the electrified work is not performed, and the personal labor protection articles are used correctly; the rated action current of the leakage protector of the total distribution box is less than 250mA, the action time is less than 0.2s, the rated leakage action current of the leakage protector of the switch box is less than 30mA, the action time is less than 0.ls, the leakage protection of a wet place adopts a splash-proof product, and the rated leakage action current is less than 15mA; the movable distribution box adopted according to the field needs is arranged at each construction point, moves upwards along with a construction layer, is overhead and insulated as far as possible when a line is laid, and the power lines of the handheld electric tool and the electric welding machine are not more than 5m at maximum; the power supply voltage of 36v for lighting in places with high temperature, conductive dust, lamp ground height lower than 2.4m and the like and the power supply voltage of 12v for lighting in wet places; the distribution box and the switch box are provided with a rain-proof shed, the box body is tightly and rightly arranged, and a door lock is arranged; electricians can support the evidence and go on duty, establish electricity files, make various electricity records day by day, strictly forbid non-electricians to overhaul, operate electric equipment and lay and lap up electricity lines; the primary distribution box on site is not allowed, any person cannot open and close the switch at will, the secondary distribution box switch operation must be operated by electrician, and a 'forbidden closing' card is hung when the switch is closed and overhauled;

occupational safety management measures of a coal gas area: the carbon monoxide content of the gas area operation should not exceed 25PPm, can operate for a long time, but should make precautionary measures; when personnel participating in maintenance work need to pass through the safety bottoming, make self-precaution measures, carry a CO detector and prepare an air respirator, the personnel should work cooperatively at more than two people and stand up the wind place, the personnel are prohibited from individually entering the gas area for operation, and special personnel are arranged for monitoring during the operation; when the gas is constructed in a gas area, the carbon monoxide content is detected, and after the carbon monoxide content is detected to be qualified, the gas can be used in the gas area, constructors must wear a gas detector, the constructors hold a gas license, a full-time guardian is arranged, and when the carbon monoxide content is not more than 25ppm, the gas can work for a long time; when the carbon monoxide content is not more than 50ppm, the continuous working time in the process is not more than 1 hour; when the PPm exceeds 50PPm, the operation of wearing an air respirator is needed; when the gas area works, a safety warning sign is set up, a red and white rope loop is used for warning, and after the work is finished, the gas area is immediately evacuated, and the gas area cannot stay or rest; the gas area uses an explosion-proof safety lighting lamp; the confirmation time is confirmed 30 minutes before operation, the gas content is lower than 24PPm, and a gas detector is provided; confirming that the precautionary measures, guardians and warning measures are in place, prohibiting non-operation personnel from entering, and rapidly evacuating personnel in the field under abnormal conditions to ensure the smoothness of the escape channel;

Emergency measures in special operation stage: fire accident: when a fire accident occurs, immediately alarming a fire alarm, timely reporting to a workshop leader, adopting a fire extinguishing mode according to different fire types, for example, igniting the inside of a pipeline, cutting off inflammable medium, and adopting nitrogen to extinguish the fire; external fire is caught, fire-fighting water and fire-extinguishing equipment are used for rescue work; when electricity and oil cause fire, the power supply is cut off firstly, then the fire is extinguished, a fire extinguisher is adopted to extinguish the fire, or a spade is used to fight the fire by soil (sand), and water is strictly forbidden to extinguish the fire; meanwhile, the casualties are sent to a hospital in time, self rescue is carried out according to site conditions, and the operators rapidly withdraw from the accident site by plugging the mouth and nose with clothes; gas poisoning accident: the on-site commander should be calm and not blindly rescue people to avoid further expansion of accident disasters, a correct processing method is required to be made according to the on-site accident hazard degree, once people are found out of gas poisoning, all operators are rapidly organized to withdraw to a safe area along the upwind direction, people are immediately checked by the airlines of each area, victims are rapidly withdrawn to the air circulation area, rescue phone numbers are immediately dialed, the situation of poisoning places, the number of poisoning people, the poisoning degree and the like is informed, and people are dispatched to the intersection with obvious marks to receive the attention; high-altitude falling accident: if a high-altitude falling accident occurs, the site responsible person should immediately dial emergency calls, report the leading of a workshop, stop bleeding and bind the wounded person if the condition exists, keep smooth breath, and if suffocation is found, timely remove the respiratory infarction and respiratory skill disorder, immediately unlock the collar of the wounded person, clear the foreign matters on the mouth and nose of the wounded person and the like, and actively cooperate with a hospital to rescue; restricted space asphyxia: when a guardian finds an anoxic choking condition during operation in a closed space, the guardian cannot take rescue immediately, and adopts various emergency measures prepared before the operation, ventilation facilities, air respirators, ropes, ladders and the like are used for rapidly transferring a wounded person to an air circulation position, the collar is loosened, so that the wounded person breathes smoothly, and emergency calls are timely dialed for rescue; lifting injury accident: the hoisting operation accidents mainly comprise extrusion, high falling, object hanging falling, impact and the like, when a hoisting mechanical accident occurs, a site responsible person timely reports a workshop leader, whether an inspector is injured or not, whether adjacent equipment facilities are affected or not, a warning area is pulled on site, emergency telephones are timely dialed, special persons are arranged to answer rescue vehicles at important identification intersections, and a safety channel is ensured to be smooth.

In step 6, the quality control gist: the steel member and the refractory material are subjected to quality inspection after entering the site so as to confirm whether deformation, damage and defect exist in the transportation process and are timely processed by related departments; the construction team should check whether the geometric dimension, pitch, etc. of the components meet the regulations before installation, and should report to the relevant departments after the problems are found, in principle, the construction team must finish the treatment before installation; the management of the welding process is responsible for the arrival of people and falls to the actual place; the assembly is carried out according to the requirement, and the size is strictly controlled;

quality control measures: the technical responsibility and the construction responsibility in each working procedure during the construction period make technical arrangement for the requirements, ensure that the quality percent of pass is 100 percent qualified, and the hearth cleaning and acceptance standard: all the materials such as residual iron, coke and removed brick lining in the furnace are completely cleared out of the furnace in time, the working surface of the cooling wall and the upper surface of the fourth layer of carbon bricks on the side wall are completely exposed, any attachments cannot be thoroughly cleaned, the conditions that the side wall carbon bricks, the iron notch combined bricks and the tuyere combined bricks are rebuilt in the furnace are met, and in order to better protect the ceramic pad, the thickness of residual iron on the surface of the ceramic pad is less than or equal to 150mm thick, cleaning is not recommended, because if the ceramic pad is brought up by cleaning items, the thickness of precipitated mixed slag iron on the surface of the ceramic pad is less than or equal to 450mm thick, and only drilling separation can be used in cleaning, so that the ceramic pad cannot be ensured to be intact.

In the step 7, the environmental protection and civilized construction measures are as follows: before construction, environmental protection education is carried out, incineration of asphalt, asphalt felt, rubber, garbage and other toxic substances generating malodorous gas is forbidden, protection measures such as sealing must be adopted in the process of loading, unloading and transporting materials with emission or leakage of toxic substances, harmful gases, liquid, dust and harmful gases, dust purging with compressed air and high-level dust accumulation are forbidden, throwing and dust raising are forbidden, dust raising measures are required in construction, the detached groove waste in construction is stored according to a designated place, no sundries are required to be stacked everywhere and placed in disorder, and the construction site is required to carry out site civilization construction, project construction is completed and three-clean refund.

Although the present disclosure describes embodiments, not every embodiment is described in terms of a single embodiment, and such description is for clarity only, and one skilled in the art will recognize that the embodiments described in the disclosure as a whole may be combined appropriately to form other embodiments that will be apparent to those skilled in the art.

Claims

1. The safe and environment-friendly shutdown method of the oversized blast furnace, which is favorable for discharging clean residual iron, is characterized by comprising the following steps of: the method comprises the following steps:

step 1: preparing before construction;

step 7: environmental protection and civilized construction measures.

2. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 1, protective measures are taken for the equipment and the components which enter the field, unqualified construction materials strictly forbid the entering the field, and construction rest areas, tools and material stacking places are required to be arranged according to requirements; power sources such as practical electricity and the like; the tools and equipment which arrive at the site need to be arranged in place according to the requirements, so that the orderly penetration among the working procedures is ensured; the field is required to be provided with a distribution box, so that sufficient power supply is ensured, safety accessories of electric appliances are required to be intact, the welding machine shell is required to be grounded, and the conducting wires are required to be insulated well.

3. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in said step 2, the shift of the field existing equipment facility: according to the existing equipment and pipeline arrangement condition of the blast furnace hearth and the direction of a railway, determining that a residual iron port is approximately positioned on a hearth cooling wall, implementing uncoupling of a cooling wall water pipe, redirecting the cooling wall water pipe, and freeing the position where the residual iron channel flows through, and carrying out displacement or heat insulation protection measures on cables and a bridge of an electric valve of a dedusting pipeline at the hearth part, wherein some small impurity pipelines of the hearth are displaced;

4. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 3, the residual iron placing operation mainly comprises the following steps: checking and confirming an iron residue placing condition system, namely rapidly cutting a furnace shell and a cooling wall mud sleeve mud frame by using high oxygen, measuring the temperature of a carbon brick, making a mud sleeve, tamping the carbon brick and a main ditch refractory material, baking the mud sleeve and the iron drop point refractory material for 1-2 hours until the surface of the refractory material turns red, drilling the iron residue by using a YT28 type rock drilling machine for one, two or three eyes, measuring the drilling temperature while drilling, determining which eye is used for discharging the iron residue after finding out the red point of the drilling, and because the condition of an iron residue placing operation site is limited, particularly the operation space is narrow, an operation platform cannot be built widely, a non-operator can not ban the operation platform for placing the iron residue on tightly, particularly after the red point appears in the iron residue eye, the operator can ban the operation platform to stand right, the operation in the main ditch is banned tightly, the two sides of the main ditch must be closed to a safety channel, the operation platform is controlled to operate the number of people to be less than 8, and after the last iron residue is discharged by the stop furnace, the operation platform is ready for manufacturing the iron residue opening; closing cooling wall water at the position of a scrap iron port in advance, cutting off a water pipe, blowing stored water by using compressed air, drawing boundary lines of a scrap iron port frame on a furnace shell, burning and cutting furnace skins and cooling walls at the position of the scrap iron port by using high oxygen, controlling the size to be 600 multiplied by 800mm, cutting and removing the furnace skins at the position of the scrap iron port by using high oxygen, burning the cooling walls, firstly burning red cooling walls, observing water outlets of the cooling walls, continuously blowing the water inlet and outlet pipes of the cooling walls by using the compressed air if a large amount of steam is emitted to indicate that the stored water is not blown out, cutting and cooling wall operation is needed to be stopped, digging and removing cold face ramming materials of carbon bricks after the cooling walls are burnt, measuring the surface temperature of the carbon bricks, if the surface temperature of the carbon bricks is lower than 150 ℃ to indicate that the thickness of the carbon bricks is higher than 800mm, otherwise indicating that the residual carbon bricks are thinner, adjusting the size and depth of drilling, paying attention to safety, ramming and paving a layer of refractory bricks at the bottom layer, the thickness of the mud sleeve is 75mm, the depth of the mud sleeve from the furnace skin is not less than 200mm, the thickness of the mud sleeve is not less than 300mm, timber is used for baking the refractory material around the iron notch, the mud sleeve is ensured to be dried, the mud sleeve is not suitable for baking by using gas fire, inflammable and explosive substances in the iron notch discharging area are all cleaned up in advance, the lowest drilling is firstly carried out at one eye, the drilling is stopped until red is seen, then two holes are drilled, the drilling is stopped until red is seen, finally three holes are drilled, the drilling is stopped until red is seen, according to the conditions of the three holes, the lowest iron notch which can possibly be discharged is taken as the main iron notch, the drilling is carried out again to directly drill through the iron notch, then the tail part of the drill rod is removed, if the drill rod is left in the iron notch channel, the tail part of the drill rod is burnt through by oxygen, when the iron notch is discharged, the residual iron is reduced, or the slag is discharged after the iron notch is cut off, the cold air is fed to a blast furnace through a blast furnace blower, the slag is discharged by slight positive pressure, the wind pressure is about 60-100kpa, which is favorable for the excessive discharge of residual iron.

5. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 4, the residual iron blocks outside the hearth are cleaned and transported: removing and cleaning the residual iron blocks, residual iron ditches, diversion ditches, iron receiving pits, platform rails, refractory materials, sand materials and other facilities or sundries generated by the blast furnace residual iron discharge, transporting to a designated position area, estimating the distance to be about 150 meters, the normal iron-sinking block is mainly dumped by a forklift, and the reserved pit residual iron block is dumped or dumped after being cut by a rope after being cut at night;

6. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 5, the temporary electricity management measure of the construction site: the installation, the dismantling and the maintenance of the temporary power utilization of the construction must be completed by electricians strictly according to technical operation rules; all electrical panel boxes, machine equipment and the like in the construction site are reliably grounded or protected by zero connection; all the distribution boxes are required to be orderly arranged, one machine, one gate and one insurance are implemented, one gate and multiple machines are strictly forbidden, and the switch is required to be provided with a leakage protector; the capacity of each level of distribution device is matched with the load, the structure form, the disc surface arrangement and the system wiring are standardized, and the moisture-prone and explosion-prone articles on the construction site are strictly managed and used according to the moisture-proof, explosion-proof and fireproof safety standards; the damaged wires and cables are forbidden, and the wires and cables in the use process must be covered by channel steel and the like, so that rolling and burning are prevented; the electric equipment is strictly grounded, and the resistance of the grounding wire is not more than 4Ω; the construction cable must be highly insulated; the rated action current of the leakage protector of the total distribution box is less than 250mA, the action time is less than 0.2s, the rated leakage action current of the leakage protector of the switch box is less than 30mA, the action time is less than 0.ls, the leakage protection of a wet place adopts a splash-proof product, and the rated leakage action current is less than 15mA;

7. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 6, the quality control point is as follows: the steel member and the refractory material are subjected to quality inspection after entering the site so as to confirm whether deformation, damage and defect exist in the transportation process and are timely processed by related departments; the construction team should check whether the geometric dimension, pitch, etc. of the components meet the regulations before installation, and should report to the relevant departments after the problems are found, in principle, the construction team must finish the treatment before installation; the management of the welding process is responsible for the arrival of people and falls to the actual place; the assembly is carried out according to the requirement, and the size is strictly controlled.

8. The ultra-large blast furnace safe and environment-friendly blowing-out method beneficial to clean residual iron as set forth in claim 1, wherein the method comprises the following steps: in the step 7, the environmental protection and civilized construction measures are as follows: the environmental protection management system and related environmental protection regulations of iron works are executed in construction, the environmental protection education is carried out before construction, the incineration of asphalt, asphalt felt, rubber, garbage and other toxic substances generating malodorous gases are forbidden, the emission or leakage of toxic and harmful gases, liquid, dust and harmful gases are forbidden, the protection measures such as sealing are needed in the process of loading, unloading and transporting, the blowing of dust and high-level dust accumulation by compressed air is forbidden, the throwing and dust raising are forbidden, the dust raising prevention measures are needed in construction, the detached groove waste in construction is stored according to the appointed place, no sundries are needed to be randomly piled and placed, any sundries are needed to be piled on the construction site, the on-site civilized construction is needed, the project construction is completed, and the three-clean returning is needed.