CN112934361B - Molten steel slag disc type air-cooled double-rotating-roller crushing treatment device and method - Google Patents

Molten steel slag disc type air-cooled double-rotating-roller crushing treatment device and method Download PDF

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Publication number
CN112934361B
CN112934361B CN202110360707.3A CN202110360707A CN112934361B CN 112934361 B CN112934361 B CN 112934361B CN 202110360707 A CN202110360707 A CN 202110360707A CN 112934361 B CN112934361 B CN 112934361B
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China
Prior art keywords
slag
disc
double
roller
bed
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CN202110360707.3A
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Chinese (zh)
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CN112934361A (en
Inventor
吴龙
郝以党
彭犇
王会刚
胡天麒
翟慎安
李惊涛
孙健
张培才
吴跃东
张宇
岳昌盛
闾文
张鹏
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Central Research Institute of Building and Construction Co Ltd MCC Group
MCC Energy Saving and Environmental Protection Co Ltd
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Central Research Institute of Building and Construction Co Ltd MCC Group
MCC Energy Saving and Environmental Protection Co Ltd
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Priority to CN202110360707.3A priority Critical patent/CN112934361B/en
Publication of CN112934361A publication Critical patent/CN112934361A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C4/00—Crushing or disintegrating by roller mills
    • B02C4/02—Crushing or disintegrating by roller mills with two or more rollers
    • B02C4/08—Crushing or disintegrating by roller mills with two or more rollers with co-operating corrugated or toothed crushing-rollers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C23/00—Auxiliary methods or auxiliary devices or accessories specially adapted for crushing or disintegrating not provided for in preceding groups or not specially adapted to apparatus covered by a single preceding group
    • B02C23/02—Feeding devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C23/00—Auxiliary methods or auxiliary devices or accessories specially adapted for crushing or disintegrating not provided for in preceding groups or not specially adapted to apparatus covered by a single preceding group
    • B02C23/18—Adding fluid, other than for crushing or disintegrating by fluid energy
    • B02C23/24—Passing gas through crushing or disintegrating zone
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C4/00—Crushing or disintegrating by roller mills
    • B02C4/28—Details
    • B02C4/286—Feeding devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C4/00—Crushing or disintegrating by roller mills
    • B02C4/28—Details
    • B02C4/30—Shape or construction of rollers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C4/00—Crushing or disintegrating by roller mills
    • B02C4/28—Details
    • B02C4/42—Driving mechanisms; Roller speed control
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B3/00—General features in the manufacture of pig-iron
    • C21B3/04—Recovery of by-products, e.g. slag
    • C21B3/06—Treatment of liquid slag
    • C21B3/08—Cooling slag
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/05—Apparatus features
    • C21B2400/052—Apparatus features including rotating parts
    • C21B2400/054—Disc-shaped or conical parts for cooling, dispersing or atomising of molten slag rotating along vertical axis
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/05—Apparatus features
    • C21B2400/052—Apparatus features including rotating parts
    • C21B2400/056—Drums whereby slag is poured on or in between
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Abstract

The invention provides a molten steel slag disc type air-cooled double-rotation roller crushing treatment device and method, wherein the device comprises a disc type crushing bed, double-rotation rollers, a rotation motor and a supporting travelling mechanism, the double-rotation rollers are rotatably arranged in the disc type crushing bed, the rotation motor drives the double-rotation rollers to rotate along the radial direction of the disc type crushing bed, the supporting travelling mechanism drives the double-rotation rollers to rotate along the circumferential direction, the double-rotation rollers are rotated along the radial direction to push high-temperature slag to move from the center of the disc type crushing bed to the periphery for crushing, the double-rotation rollers are rotated along the circumferential direction to push the high-temperature slag to move from the inlet of the disc type crushing bed to the outlet of the disc type crushing bed for crushing, and the double-rotation rollers are reversely tangent to the double-rotation rollers along the radial direction of the disc type crushing bed. The invention improves the steel slag treatment equipping level, improves the steel slag treatment efficiency, realizes the high-efficiency treatment of the air-cooled crushing and the waste heat recovery of the molten steel slag, and increases the comprehensive utilization benefit of the steel slag.

Description

Molten steel slag disc type air-cooled double-rotating-roller crushing treatment device and method
Technical Field
The invention relates to the technical field of steel slag treatment, in particular to a device and a method for crushing molten steel slag by using a disc-type air-cooled double-rotary roller.
Background
In 2019, the annual steel yield of China is 9.8 hundred million tons, about 120-140 kg of steel slag is produced per ton of steel produced, and the annual steel slag yield exceeds 1.2 hundred million tons. The steel slag contains two types of resources of iron metal resources, inorganic materials such as calcium silicate and the like, and has the substance attribute of resource utilization. For a long time, iron ores in China mainly depend on import, and resources are very short. The steel slag in China is expected to recover approximately 2000 ten thousand tons of iron resources, and the inorganic material reaches 8000 more than ten thousand tons, so that the method has great significance in resource recovery value.
The high-efficiency recovery of metal iron and inorganic material resources in the steel slag is carried out by crushing and separating firstly, and then separation of the two materials is realized by adopting modes of magnetic separation and the like, so that targeted recycling is obtained. The pretreatment process of the steel slag is a precondition of crushing and magnetic separation treatment of the steel slag, and realizes more efficient crushing, screening and magnetic separation of the steel slag through pretreatment under the high-temperature condition.
The existing steel slag pretreatment process comprises production processes such as a hot disintegrating method, a hot splashing method, a roller method, an air quenching method and the like, the production mode of the hot splashing method is behind, the treatment process is simple and extensive, the problems of serious environmental pollution, low metal resource recovery rate and the like exist, and the steel slag can be eliminated as soon as possible; the roller method is only suitable for liquid steel slag with good fluidity, the steel slag treatment rate is less than 50%, the equipment operation cost is high, the failure is high, and the roller method is only used for a few steel enterprises in a steel ladle system at present; the air quenching method adopts large air quantity to blow off and cool the liquid steel slag into fine particles, is only suitable for the treatment of the liquid steel slag, and has low recovery rate of steel metal iron resources.
The domestic main steel slag treatment method is a hot disintegrating method, and the process has the advantages of wide adaptability, good steel slag pulverization effect after hot disintegrating, good slag-iron separation effect, high metal iron recovery rate, qualified tailings stability and the like. The current hot-disintegrating method is divided into two processes of pool-type hot-disintegrating and pressured hot-disintegrating. The pool type hot-sealing method adopts a technical method of engineering mechanized operation, namely, an excavator is used for slagging-off and crushing high-temperature steel slag poured into a hot-sealing pool, and the equipment level and the environmental emission are required to be further improved. The pressurized hot-disintegrating mode adopts a mechanized rolling crusher to crush the high-temperature steel slag, has the advantages of high equipping and automation degree, relatively high investment, poor tightness and incapability of recovering waste heat in the crushing process by adopting a water cooling mode.
The slag temperature of the steel slag reaches 1600 ℃, and the calorific value of ton slag exceeds 50kg of standard coal, wherein a large amount of waste heat resources are contained. According to 2019, the steel slag amount of China is 1.2 hundred million tons, wherein the waste heat resource is equivalent to 600 ten thousand tons of standard coal, the corresponding economic value reaches billions yuan, and the method has huge economic market space. At present, the waste heat recovery of high-temperature slag such as surrounding metallurgical slag is often in a test research stage, and the full recycling utilization of slag heat two resources is often difficult to realize. A large number of laboratory and industrial pilot test researches are carried out on the recovery of the waste heat of the wind-quenched steel slag at home and abroad, but the method is often improper, the recovery rate of iron resources is low, the production is discontinuous, and the comprehensive economic benefit is poor, so that the production and the application cannot be carried out. In addition, the smelting slag is adopted to cool to generate water vapor or hot water for heat exchange and utilization, but the utilization rate of the waste heat is low, and the industrial operation economic condition is not provided.
Disclosure of Invention
Aiming at the problems, the invention provides a molten steel slag disc type air-cooled double-rotating-roller crushing treatment device and method, which are used for solving the problems that the steel slag treatment process and equipment in the prior art occupy large space, the system investment is high, and the waste heat cannot be recycled.
The invention provides a molten steel slag disc type air-cooled double-rotation roller crushing treatment device which comprises a disc type crushing bed, double-rotation rollers, a rotation motor and a supporting travelling mechanism, wherein the double-rotation rollers are rotationally arranged in the disc type crushing bed, the rotation motor drives the double-rotation rollers to rotate around the radial direction of the disc type crushing bed, the supporting travelling mechanism drives the double-rotation rollers to rotate along the circumferential direction, the double-rotation rollers are rotationally pushed to move and crush high-temperature slag from the center of the disc type crushing bed to the periphery, the double-rotation rollers are rotationally pushed to rotationally move and crush the high-temperature slag along the circumferential direction from an inlet to an outlet of the disc type crushing bed, and the double-rotation rollers are reversely tangent to the double-rotation rollers along the radial direction of the disc type crushing bed.
Further, the disc-type crushing bed comprises a slag inlet, a disc cover, a disc wall, a slag layer, a cushion layer, a bottom bed, grate bars, a wind hearth, a slag hole and a water seal groove, wherein the slag inlet is close to the center of the top of the disc cover on the upper part of the disc-type crushing bed, the disc cover is arranged on the top of the disc-type crushing bed, the disc wall is arranged on the outer side of the disc-type crushing bed for a circle, the slag layer is arranged above the cushion layer above the bottom bed of the disc-type crushing bed, the grate bars are arranged in the bottom bed, the wind hearth is communicated with the bottom bed, the slag hole is radially opened on one side of the bottom bed below the bottom bed and the wind hearth, and the water seal groove is arranged at the joint between the disc cover, the disc wall and the bottom bed.
Further, the double-rotation roller comprises a roller shaft, roller teeth, a central shaft, a shaft seat and a connecting seat, wherein the roller teeth are fixedly arranged on the roller shaft, the central shaft and the connecting seat are vertically arranged, two ends of the roller shaft are respectively and horizontally crossed and rotatably connected with the top of the central shaft and the top of the connecting seat, the shaft seat is fixedly arranged in the middle of the lower part of the disc-type crushing bed, the central shaft and the shaft seat are rotatably and coaxially arranged, the roller shaft rotatably penetrates through the disc wall, the connecting seat is arranged on the outer side of the disc-type crushing bed through the roller shaft, the fixed end of the rotation motor is fixedly connected with the connecting seat, and the output end of the rotation motor drives the roller shaft to rotate around the radial direction of the disc-type crushing bed between the central shaft and the connecting seat.
Further, support running gear includes ring gear, turnover motor, running roller, rail, ring gear, rail are along disk crushing bed periphery annular setting, and the connecting seat rigid coupling of ring gear and double-rotation roller, and the connecting seat of double-rotation roller is located on the rail through the running roller is rotatory, and turnover motor and ring gear meshing are through the disk wall of double-rotation roller drive disk crushing bed turnover along the circumferencial direction around the axle bed.
Further, the slag inlet is of a cylindrical structure at the inner part of the disc-type crushing bed, the diameter is not lower than 1000mm, the slag inlet is of an inverted cone structure at the outer part of the disc-type crushing bed, the uppermost diameter is not lower than 3000mm, the bottommost diameter is equal to the inner part of the disc-type crushing bed, the main body of the slag inlet is of a steel structure, the thickness of the steel structure is not lower than 8mm, the inner side of the steel structure is made of refractory materials, the thickness of the refractory materials is not lower than 50mm, the slag outlet is of a rectangular structure, the length of the slag outlet is not lower than 2000mm, and the width of the slag outlet is not lower than 1000mm.
Further, the disc cover is a disc-type closed cover which covers the disc-type crushing bed, the disc wall is closed at one periphery of the outer side of the disc-type crushing bed, the disc cover and the disc wall main body are made of steel structural materials, the thickness of the steel structural materials is not less than 6mm, refractory materials are arranged on the inner side of the steel structure, and the thickness of the refractory materials is not less than 30mm.
Further, the double-rotation roller is provided with 2-4 roller shafts, each roller shaft is uniformly distributed along the radial direction of the disc-type crushing bed, the roller teeth are uniformly distributed along the axial direction and the radial direction of the roller shaft, and 2-4 roller teeth are arranged in the same radial direction of the roller shaft.
Further, the double-rotation roller is provided with 3 roller shafts, 3 roller teeth are arranged in the same radial direction of the roller shafts, the diameter of the roller shafts is not less than 400mm, the width of the roller teeth is 50-400mm, the length of the roller teeth is 500-1500mm, and the diameter of the central shaft is not less than 300mm.
The invention also provides a method for crushing the molten steel slag disc type air-cooled double-rotary-roller crushing treatment, which adopts the molten steel slag disc type air-cooled double-rotary-roller crushing treatment device to crush the high-temperature slag and comprises the following steps:
s1, lifting a slag tank containing high-temperature slag by a crane and placing the slag tank on a slag pouring machine, tilting the slag pouring machine according to a certain speed, pouring the high-temperature slag into a disc-type crushing bed through a slag inlet, and forming a slag layer on the upper part of a cushion layer on a bottom bed by the high-temperature slag;
s2, when the slag is poured, the double-rotation roller is driven by the rotation motor and the turnover motor to realize rotation and turnover, the high-temperature slag is stirred by the roller teeth under the rotation action of the double-rotation roller, the slag is removed and crushed, and meanwhile, the slag layer formed by the high-temperature slag is pushed to move under the turnover action of the double-rotation roller;
s3, circulating air provided by a fan in the treatment process sequentially passes through the breeze chamber, the bottom bed, the cushion layer and the slag layer to realize heat convection of high-temperature slag until the high-temperature slag is cooled to a certain temperature;
s4, cooling and crushing the high-temperature slag in the steps S1-S3, discharging the slag through a slag outlet, converting cold air and a slag layer into hot air through convection heat exchange, and conveying the hot air out through a pipeline for waste heat utilization.
Further, in the step S2, the rotation speed of the double-rotating roller is 3-60 revolutions per minute, the turnover speed is 2-20 revolutions per hour, the blast cooling treatment time of the high-temperature slag is 20-60 minutes, and the cooling air quantity of ton steel slag is not less than 2000m in the step S3 3 The wind pressure is not lower than 3000Pa.
The device and the method for crushing the molten steel slag by using the disc-type air-cooled double-rotating roller have the advantages of high automation level, strong production continuity, high operation efficiency, small space occupation, strong tightness, low system investment, high waste heat recovery rate and the like, realize the crushing pretreatment of the high-temperature steel slag, realize the breakthrough of recycling the waste heat of the steel slag, and are the crossing type upgrade of the technical equipment of the existing steel slag treatment process.
The invention adopts the disc-type crushing bed, the double-rotation roller is used as high-efficiency cooling crushing core equipment of molten steel slag, and the fixed disc-type crushing bed is used as a steel slag treatment space carrier, so that the invention has the advantages of high tightness and small occupied area; meanwhile, the novel double-rotation roller crusher is adopted to rotate around the disc-type crushing bed to efficiently crush the steel slag, the steel slag is fully stirred and crushed under the dual actions of rotation and turnover of the double-rotation roller, and a plurality of double-rotation crushing rollers are arranged in one disc-type crusher, so that the novel double-rotation roller crusher has the advantages of high crushing efficiency, high steel slag treatment capacity and the like.
In addition, in the crushing process, circulating air is adopted to wind-cool high-temperature steel slag, so that the hot air obtained by wind-cooling heat exchange can be recycled, and the waste heat recovery rate of the steel slag exceeds 70%. The high-temperature flue gas obtained by air cooling heat exchange can be subjected to waste heat recovery and power generation, the generated energy of ton slag is more than 30kWh, and the waste heat recovery economic benefit is remarkable.
The invention has the advantages that the device and the method realize the air cooling crushing and the waste heat recovery treatment of the molten steel slag, provide preconditions for the waste heat recovery and utilization of the steel slag, adopt an air cooling technology without a water supply and drainage system used by a water cooling technology, adopt circulating air cooling without fume discharge in the treatment process, avoid the generation of wet fume compared with the traditional technology, greatly reduce the investment of public and auxiliary facilities such as high alkaline wet fume treatment, greatly improve the equipment level of the steel slag treatment, improve the treatment efficiency of the steel slag, break through the difficult problem of the waste heat recovery and utilization of the steel slag, thoroughly solve the emission problem in the steel slag treatment process, increase the comprehensive utilization benefit of the steel slag, greatly reduce the investment of public and auxiliary facilities such as water, dust removal and the like, effectively reduce the production operation cost of the steel slag, and have outstanding economic and social benefits.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.
FIG. 1 is an overall schematic diagram of a molten steel slag pan type air-cooled twin-roll crushing treatment device provided by the invention;
FIG. 2 is a schematic top view of a molten steel slag pan type air-cooled twin-roll crushing treatment device provided by the invention;
fig. 3 is a schematic diagram showing the distribution of double-rotation roller teeth on a roller shaft of the molten steel slag disc type air-cooled double-rotation roller crushing treatment device.
Reference numerals illustrate:
1-slag pot, 2-slag pouring machine, 3-high temperature slag, 4-slag pulling machine, 5-disc crushing bed, 6-slag inlet, 7-disc cover, 8-disc wall, 9-double-rotation roller, 10-roller shaft, 11-roller tooth, 12-slag layer, 13-rotation motor, 14-gear ring, 15-turnover motor, 16-roller, 17-steel rail, 18-cushion layer, 19-bottom bed, 20-grate bar, 21-air hearth, 22-slag outlet, 23-water seal tank, 24-central shaft, 25-shaft seat, 26-fan, 27-air pipe and 28-connecting seat.
Detailed Description
In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Example 1
Referring to fig. 1, the invention provides a molten steel slag disc-type air-cooled double-rotary-roller crushing treatment device, which comprises a disc-type crushing bed 5, double-rotary rollers 9, a rotary motor 13 and a supporting travelling mechanism, wherein the double-rotary rollers 9 are rotationally arranged in the disc-type crushing bed 5, the rotary motor 13 drives the double-rotary rollers 9 to rotate around the radial direction of the disc-type crushing bed 5, the supporting travelling mechanism drives the double-rotary rollers 9 to rotate along the circumferential direction, the double-rotary-rollers 9 rotate along the radial direction to push high-temperature slag 3 to move and crush from the center of the disc-type crushing bed 5 to the periphery, and the double-rotary-rollers 9 rotate along the radial direction of the disc-type crushing bed 5 to move and crush from the inlet to the outlet of the disc-type crushing bed 5, and the double-rotary-rollers 9 rotate reversely tangentially along the radial direction of the disc-type crushing bed 5.
The disc-type crushing bed 5 comprises a slag inlet 6, a disc cover 7, a disc wall 8, a slag layer 12, a cushion layer 18, a bottom bed 19, a grate 20, a wind hearth 21, a slag outlet 22 and a water seal groove 23, wherein the slag inlet 6 is close to the center of the top of the disc cover 7 at the upper part of the disc-type crushing bed 5, the disc cover 7 is arranged at the top of the disc-type crushing bed 5, the disc wall 8 is arranged on the outer side of the disc-type crushing bed 5 for a circle, the slag layer 12 is arranged above the cushion layer 18, the cushion layer 18 is arranged above the bottom bed 19 of the disc-type crushing bed 5, the grate 20 is arranged in the bottom bed 19, the wind hearth 21 is communicated below the bottom bed 19, the slag outlet 22 is radially opened at one side of the bottom bed 19 below the wind hearth 21, the water seal groove 23 is arranged at the joint between the disc cover 7, the disc wall 8 and the bottom bed 19, and the slag inlet 6 and the slag outlet 22 are axially projected at an angle of 30-90 DEG, preferably 60 DEG, at the bottom bed 19.
The double-rotation roller 9 comprises a roller shaft 10, roller teeth 11, a central shaft 24, a shaft seat 25 and a connecting seat 28, wherein the roller teeth 11 are fixedly arranged on the roller shaft 10, the central shaft 24 and the connecting seat 28 are vertically arranged, two ends of the roller shaft 10 are respectively and horizontally crossed and rotatably connected with the top of the central shaft 24 and the top of the connecting seat 28, the shaft seat 25 is fixedly arranged at the middle part below the disc-type crushing bed 5, the central shaft 24 and the shaft seat 25 are rotatably and coaxially arranged, the connecting seat 28 is arranged at the outer side of the disc-type crushing bed 5 through the roller shaft 10, the fixed end of the rotation motor 13 is fixedly connected with the connecting seat 28, and the output end of the rotation motor 13 drives the roller shaft 10 to rotate around the radial direction of the disc-type crushing bed 5 between the central shaft 24 and the connecting seat 28.
The supporting travelling mechanism comprises a gear ring 14, a turnover motor 15, rollers 16 and steel rails 17, wherein the gear ring 14 and the steel rails 17 are annularly arranged along the periphery of the disc-type crushing bed 5, the gear ring 14 is fixedly connected with a connecting seat 28 of the double-rotation roller 9, the connecting seat 28 of the double-rotation roller 9 is rotatably arranged on the steel rails 17 through the rollers 16, and the turnover motor 15 is meshed with the gear ring 14 through gears to drive the disc wall 8 of the disc-type crushing bed 5 to rotate around a shaft seat 25 along the circumferential direction.
The slag inlet 6 is of a cylindrical structure at the inner part of the disc-type crushing bed 5, the diameter is not lower than 1000mm, the slag inlet 6 is of an inverted cone structure at the outer part of the disc-type crushing bed 5, the uppermost diameter is not lower than 3000mm, the bottommost diameter is equal to the inner part of the disc-type crushing bed 5, the main body of the slag inlet 6 is of a steel structure, the thickness of the steel structure is not lower than 8mm, the inner side of the steel structure is made of refractory materials, and the thickness of the refractory materials is not lower than 50mm.
The disc cover 7 is a disc-shaped airtight cover which covers the disc-shaped crushing bed 5, the roll shaft 10 penetrates through the disc wall 8 in a rotatable mode, the disc wall 8 is sealed on the periphery of the outer side of the disc-shaped crushing bed 5, the disc cover 7 and the main body of the disc wall 8 are made of steel structural materials, the thickness of the steel structural materials is not less than 6mm, refractory materials are arranged on the inner side of the steel structure, and the thickness of the refractory materials is not less than 30mm.
The double-rotation roller 9 is provided with 2-4 roller shafts 10, each roller shaft 10 is uniformly distributed along the radial direction of the disc-type crushing bed 5, the roller teeth 11 are uniformly distributed along the axial direction and the radial direction of the roller shaft 10, and 2-4 roller teeth 11 are arranged along the same radial direction of the roller shaft 10.
The double-rotation roller 9 is provided with 3 roller shafts 10, 3 roller teeth 11 are arranged in the same radial direction of the roller shafts 10, the diameter of the roller shafts 10 is not less than 400mm, the width of the roller teeth 11 is 50-400mm, the length is 500-1500mm, and the diameter of the central shaft 24 is not less than 300mm.
Example 2
Referring to fig. 1, the disc-type air-cooled double-rotating-roller crushing treatment device for molten steel slag further comprises a slag pot 1, a slag pouring machine 2, high-temperature slag 3, a slag pulling machine 4, a fan 26 and an air pipe 27, wherein the slag pot 1 is arranged on the slag pouring machine 2, the high-temperature slag 3 is arranged in the slag pot 1, the slag pulling machine 4 is arranged on the side part of the slag pouring machine 2, a disc-type crushing bed 5 is arranged below the slag pouring machine 2, and the disc-type crushing bed 5 and the fan 26 are connected through the air pipe 27.
The slag pot 1 is used for Cheng Gaowen slag 3, and the slag pouring machine 2 can automatically roll over the slag pot 1, wherein the roll-over angle is 0-180 degrees.
The disc-type crushing bed 5 is of a circular disc-shaped full-closed structure, the diameter of the disc-type crushing bed 5 is 5-30m, the main structure is made of steel structural materials, the roll shaft 10 is made of heat-resistant steel materials, the roll shaft 10 is protected by forced water cooling, and the roll teeth 11 are made of heat-resistant and wear-resistant steel materials; the upper half of the roller teeth 11 close to the roller shaft 10 is protected by forced cooling.
The thickness of the slag layer 12 is 100-800mm, the thickness of the cushion layer 18 is not less than 50mm, the cushion layer 18 can adopt normal-temperature steel slag, slag and waste stone particles as raw materials, and the diameter of the steel slag particles is not less than 10mm.
The bottom bed 19 is of a steel structure, steel structure grate bars 20 are arranged at the bottom of the bottom bed 19, the thickness of each grate bar 20 is not less than 10mm, and the interval between two adjacent grate bars 20 is 5-50mm.
The breech 21 is made of steel structure materials, the thickness of the materials is not less than 5mm, and the space height of the breech 21 is not less than 500mm.
The slag outlet 22 is of a rectangular structure, is opened at one side of the bottom bed 19 along the radial direction, has the length not less than 2000mm and the width not less than 1000mm; the slag hole 22 is made of steel structure material, and the thickness of the material is not less than 5mm.
The water seal tank 23 is made of steel structure materials, the thickness of the materials is not less than 5mm, the internal width of the water seal tank 23 is not less than 50mm, and the depth is not less than 80mm.
The central shaft 24 is of a steel structure cylindrical structure, adopts heat-resistant and wear-resistant steel materials, adopts forced cooling protection, and the shaft seat 25 is a concrete or steel structure support.
The air duct 27 is made of steel structure materials, the thickness of the materials is not less than 3mm, the outside of the air duct 27 is made of inorganic heat insulation materials, and the thickness of the materials is not less than 30mm. The fan 26 is a high temperature resistant circulating fan and can bear the highest wind temperature not lower than 180 ℃.
Example 3
The roll shaft 10 of the double-rotation roll 9 is driven by the self-rotation motor 13 to rotate, so that the roll teeth 11 are driven to rotate around the roll shaft 10; the rotation direction of the roll shaft 10 can be changed by adjusting the rotation direction of the self-rotation motor 13, and the roll shaft 10 rotates in the forward direction when the self-rotation motor 13 rotates in the forward direction, and otherwise rotates in the reverse direction.
The outer gear ring 14 of the double-rotation roller 9 is driven by the turnover motor 15 to realize the rotation of the roller 16 of the double-rotation roller 9 around the outer steel rail 17 of the disc-type crushing bed 5; the rotation direction of the double-rotation roller 9 is changed by adjusting the rotation direction of the turnover motor 15, and the double-rotation roller 9 rotates in the forward direction when the turnover motor 15 rotates in the forward direction, and rotates in the reverse direction when the turnover motor rotates in the reverse direction.
The invention also provides a method for crushing the molten steel slag disc type air-cooled double-rotary-roller, which adopts the molten steel slag disc type air-cooled double-rotary-roller crushing treatment device to crush the high-temperature slag 3 and comprises the following steps:
s1, lifting a slag pot 1 containing high-temperature slag 3 by a crane and placing the slag pot on a slag pouring machine 2, tilting the slag pouring machine 2 according to a certain rate, pouring the high-temperature slag 3 into a disc-type crushing bed 5 through a slag inlet 6, and forming a slag layer 12 on the upper part of a cushion layer 18 of the high-temperature slag 3 on a bottom bed 19;
s2, when the slag is poured, the double-rotation roller 9 is driven by the rotation motor 13 and the turnover motor 15 to realize rotation and turnover, the high-temperature slag 3 is stirred by the roller teeth 11 under the rotation action of the double-rotation roller 9, the slag is removed and crushed, and meanwhile, the slag layer 12 formed by the high-temperature slag 3 is pushed to move under the turnover action of the double-rotation roller 9;
s3, circulating air provided by a fan 26 in the treatment process sequentially passes through the air chamber 21, the bottom bed 19, the cushion layer 18 and the slag layer 12 to realize heat convection of the high-temperature slag 3 until the high-temperature slag is cooled to a certain temperature;
s4, cooling and crushing the high-temperature slag 3 in the steps S1-S3, discharging the slag through a slag hole 22, converting cold air and a slag layer 12 into hot air through convection heat exchange, and conveying the hot air out through an air pipe 27 for waste heat utilization.
Further, in the step S2, the rotation speed of the twin roller 9 is 3-60 rpm, the turnover speed is 2-20 rpm, and the steel slag treatment rate can be increased by increasing the rotation speed and turnover speed of the twin roller 9, otherwise, the steel slag treatment rate is decreased.
Further, in the step S3, the blast cooling treatment time of the high-temperature slag 3 is 20-60 minutes, and the cooling air quantity of ton steel slag is not less than 2000m 3 Wind (wind)The pressure is not lower than 3000Pa, the air quantity of the fan 26 can be increased to adjust the treatment time and the slag discharging temperature in the air blast cooling process, the treatment time and the slag discharging temperature can be reduced by increasing the air quantity, and otherwise, the treatment time and the slag discharging temperature are increased.
Further, the slag pouring operation time of a single slag pot 1 by adopting a slag pouring machine 2 is 3-30 minutes, and the mass proportion of the steel slag with the grain size less than 200mm after the high-temperature slag 3 is subjected to cooling crushing treatment is not less than 70%; the temperature of the treated steel slag is adjustable, and the regulation and control range is 100-600 ℃.
Further, the fan 26 may provide cooling air at ambient temperature or circulating cooling air, and preferably circulating cooling air is used; the temperature of hot air formed by the convection heat exchange of the slag layer 12 formed by the high-temperature slag 3 is 250-600 ℃, the temperature of the circulating cooling air obtained after the utilization of the residual heat of the hot air is 100-200 ℃, and the recovery rate of the residual heat of the steel slag exceeds 70%.
Further, for the high-temperature slag 3 with good fluidity, uniform slag pouring can be realized by adjusting the rotation speed of the slag pouring machine 2; corresponding to the high-temperature slag 3 with poor fluidity, when the rotating angle of the slag pouring machine 2 exceeds 30 degrees and uniform slag discharge can not be realized, the slag pulling operation is carried out by adopting the slag pulling machine 4, and the high-temperature slag 3 is uniformly pulled into the disc-type crushing bed 5.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (7)

1. The utility model provides a molten steel slag disc-type forced air cooling double-rotation roller crushing processing apparatus, which is characterized in that, including disc-type crushing bed (5), double-rotation roller (9), rotation motor (13), support running gear, disc-type crushing bed (5) are including dish cover (7), dish wall (8), double-rotation roller (9) locate in disc-type crushing bed (5) rotationally, double-rotation roller (9) rotationally run through dish wall (8), rotation motor (13) drive double-rotation roller (9) rotate around disc-type crushing bed (5) radial direction, support running gear drive double-rotation roller (9) rotate along the circumference direction, double-rotation roller (9) radial direction rotation promotes high temperature slag (3) to remove the crushing from the center to periphery of disc-type crushing bed (5), double-rotation roller (9) are including roller (10), roller tooth axle seat (24), center axle seat (25), connection (28), support running gear (17) are including annular ring (17), ring gear (17) are located along the periphery of disc-type crushing bed (5), the gear ring (14) is fixedly connected with a connecting seat (28) of the double-rotation roller (9), the connecting seat (28) of the double-rotation roller (9) is rotationally arranged on the steel rail (17) through a roller (16), and the turnover motor (15) is meshed with the gear ring (14) through gears, so that the disc wall (8) of the disc type crushing bed (5) is driven by the double-rotation roller (9) to rotate around the shaft seat (25) along the circumferential direction.
2. The molten steel slag disc-type air-cooled double-rotary-roller crushing treatment device according to claim 1, wherein the disc-type crushing bed (5) further comprises a slag inlet (6), a slag layer (12), a cushion layer (18), a bottom bed (19), a grate bar (20), a wind chamber (21), a slag hole (22) and a water seal groove (23), the slag inlet (6) is close to the central position at the top of a disc cover (7) at the upper part of the disc-type crushing bed (5), the disc cover (7) is arranged at the top of the disc-type crushing bed (5), a disc wall (8) is arranged on the outer side of the disc-type crushing bed (5) for a circle, the slag layer (12) is arranged above the cushion layer (18), the cushion layer (18) is arranged above the bottom bed (19) of the disc-type crushing bed (5), the grate bar (20) is arranged in the bottom bed (19), the wind chamber (21) is communicated below the bottom bed (19), the hole (22) is radially opened at one side of the bottom bed (19) and the wind chamber (21), and the water seal groove (23) is arranged between the disc cover (7) and the disc (8) and the disc bed (19).
3. The molten steel slag disc type air-cooled double-rotary-roller crushing treatment device according to claim 2, characterized in that roller teeth (11) of the double-rotary roller (9) are fixedly arranged on a roller shaft (10), a central shaft (24) and a connecting seat (28) are vertically arranged, two ends of the roller shaft (10) are respectively and horizontally crossed and rotatably connected with the top of the central shaft (24) and the top of the connecting seat (28), a shaft seat (25) is fixedly arranged in the middle below the disc type crushing bed (5), the central shaft (24) and the shaft seat (25) are rotatably and coaxially arranged, the connecting seat (28) is arranged on the outer side of the disc type crushing bed (5) through the roller shaft (10), the fixed end of a rotating motor (13) is fixedly connected with the connecting seat (28), and the output end of the rotating motor (13) drives the roller shaft (10) to rotate around the radial direction of the disc type crushing bed (5) between the central shaft (24) and the connecting seat (28).
4. The molten steel slag disc-type air-cooled double-rotating-roller crushing treatment device according to claim 2, wherein the slag inlet (6) is of a cylindrical structure at the inner part of the disc-type crushing bed (5), the diameter is not lower than 1000mm, the slag inlet (6) is of an inverted cone structure at the outer part of the disc-type crushing bed (5), the uppermost diameter is not lower than 3000mm, the bottommost diameter is equal to the inner part of the disc-type crushing bed (5), the slag inlet (6) is of a steel structure, the thickness of the steel structure is not lower than 8mm, the inner side is of refractory material, the thickness of the refractory material is not lower than 50mm, the slag outlet (22) is of a rectangular structure, the length is not lower than 2000mm, and the width is not lower than 1000mm.
5. The molten steel slag disc-type air-cooled double-rotating-roller crushing treatment device according to claim 2, wherein the disc cover (7) is a disc-type closed cover which covers the disc-type crushing bed (5), the disc wall (8) forms a closed state on the outer side of the disc-type crushing bed (5), the disc cover (7) and the disc wall (8) are made of steel structural materials, the thickness of the steel structure is not less than 6mm, refractory materials are arranged on the inner side of the steel structure, and the thickness of the refractory materials is not less than 30mm.
6. A molten steel slag disc type air-cooled double-rotary-roller crushing treatment method, which adopts the molten steel slag disc type air-cooled double-rotary-roller crushing treatment device according to any one of claims 2 to 5 to crush high-temperature slag (3), and is characterized by comprising the following steps:
s1, lifting a slag pot (1) containing high-temperature slag (3) on a slag pouring machine (2) through a crane, pouring the high-temperature slag (3) into a disc-type crushing bed (5) through a slag inlet (6) by the slag pouring machine (2) according to a certain tilting speed, and forming a slag layer (12) on the upper part of a cushion layer (18) of the high-temperature slag (3) on a bottom bed (19);
s2, when the slag is poured, the double-rotation roller (9) is driven by the rotation motor (13) and the turnover motor (15) to realize rotation and turnover, the high-temperature slag (3) is stirred by the roller teeth (11) under the rotation action of the double-rotation roller (9), the slag is removed and broken, and meanwhile, the slag layer (12) formed by the high-temperature slag (3) is pushed to move under the turnover action of the double-rotation roller (9);
s3, circulating air provided by a fan (26) in the treatment process sequentially passes through the air chamber (21), the bottom bed (19), the cushion layer (18) and the slag layer (12) to realize convective heat transfer to the high-temperature slag (3) until the high-temperature slag is cooled to a certain temperature;
s4, cooling and crushing the high-temperature slag (3) in the steps S1-S3, discharging the slag through a slag hole (22), converting cold air and a slag layer (12) into hot air through convection heat exchange, and conveying the hot air out through an air pipe (27) for waste heat utilization.
7. According to claim 6The molten steel slag disc type air-cooled double-rotating roller crushing treatment method is characterized in that in the step S2, the rotation speed of a double-rotating roller (9) is 3-60 revolutions per minute, the turnover speed is 2-20 revolutions per hour, in the step S3, the blast cooling treatment time of high-temperature slag (3) is 20-60 minutes, and the cooling air quantity of ton steel slag is not less than 2000m 3 The wind pressure is not lower than 3000Pa.
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