Iron separation and impurity removal device in granulated blast furnace slag grinding process

Abstract

The utility model discloses an iron selecting and impurity removing device in the granulating blast furnace slag grinding process, and belongs to the field of solid waste resource utilization. The device comprises an iron separation and impurity removal chute and a magnetic separator, wherein a vertical mill is connected with the iron separation and impurity removal chute through a bucket elevator; the iron selecting and impurity removing chute comprises a first pipeline, a second pipeline and a third pipeline, and iron removing magnetic drums are arranged at the joints of the first pipeline, the second pipeline and the third pipeline. A vibrating screen is arranged on the second pipeline, and a fourth pipeline is further connected to the position, located above the vibrating screen, of the second pipeline. The tail end of the third pipeline is connected with a fifth pipeline and a sixth pipeline, the third pipeline, the fifth pipeline and the sixth pipeline form a Y-shaped pipeline, and the sixth pipeline is connected to the vertical mill; a conveyor belt is arranged below the fifth pipeline, and the tail end of the conveyor belt is connected with a magnetic separator. According to the utility model, the recovery rate and quality of slag are improved, and the purity of iron particles can be greatly improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to solid waste resource utilization field, concretely relates to a kind of iron selection and impurity removal device in granulated blast furnace slag powder grinding external circulation process. BACKGROUND

[0002] Granulated blast furnace slag (referred to as slag) is a byproduct produced during pig iron smelting, and has a chemical composition similar to that of Portland cement clinker (mainly CaO, SiO2, MgO and Al2O3). Due to the quenching treatment when discharged, the slag is mostly amorphous glass structure, and stores a large amount of chemical energy, with good pozzolanic activity. After processing, it can be widely used in cement admixture, concrete admixture, high-performance building materials and other fields.

[0003] Currently, the vertical mill grinding is the most commonly used slag grinding process, with the advantages of small floor area, simple process flow and low energy consumption. In addition to the performance of the grinding equipment itself, the effective removal of iron particles in the slag is the key to improving its grinding efficiency and activity index and other comprehensive performance, and is also an important measure to protect the mill disc and roller, while achieving efficient recovery of iron materials in the slag.

[0004] The iron removal process in the slag grinding process mainly includes pre-grinding iron removal and post-grinding iron removal. Pre-grinding iron removal removes iron particles in the slag before it enters the mill through the iron removal equipment installed on the inlet conveying belt. For example, a circulating slag crushing and iron removal device is disclosed in Chinese patent CN107469997A, which filters the crushed slag by setting a screen, and recycles the slag that is not completely crushed by a spiral elevator to ensure the crushing quality of all slag. The patent realizes the collection and reuse of iron powder in the slag by setting a rotating drum and a cylindrical magnet. Post-grinding iron removal is carried out after the slag is ground, including iron removal of the mill external circulation material and iron removal of the finished material of the powder separator. Common iron removal equipment includes belt self-unloading iron remover, pipeline self-unloading iron remover and strong magnetic drum iron remover, etc.

[0005] In summary, the pre-grinding iron removal process can only remove large pieces of iron material mixed in the slag raw material, but is greatly affected by the material layer thickness and material conveying speed, and cannot effectively remove weak magnetic iron materials and iron particles wrapped in the slag. The post-grinding iron removal process mainly has the difficulty of incomplete separation of iron particles and slag powder, and the quality of the separated iron particles is low, and the loss of slag powder is large. Investigation found that the external circulation iron removal operation after grinding is the key process affecting slag iron removal, and the existing improvement scheme still has problems such as complex process flow, low quality of iron particles and high loss rate of slag powder. SUMMARY

[0006] Based on the above technical problems, the utility model provides a kind of iron separation and impurity removal device in granulated blast furnace slag grinding process.

[0007] The technical solution adopted by the utility model is:

[0008] An iron separation and impurity removal device in granulated blast furnace slag grinding process, including iron separation and impurity removal chute and magnetic separator, vertical mill is connected with iron separation and impurity removal chute by bucket elevator;

[0009] The iron separation and impurity removal chute includes first pipeline, second pipeline and third pipeline, the first pipeline is vertically arranged, the second pipeline and the third pipeline are bifurcatedly connected at the bottom end of the first pipeline, and an iron removal magnetic drum is arranged at the connection of the first pipeline, the second pipeline and the third pipeline;

[0010] A vibrating screen is arranged on the second pipeline, and a fourth pipeline is further connected above the vibrating screen on the second pipeline;

[0011] The end of the third pipeline is connected with the fifth pipeline and the sixth pipeline, the fifth pipeline is vertically arranged, the third pipeline and the sixth pipeline are bifurcatedly connected at the top end of the fifth pipeline, and the sixth pipeline is connected to the vertical mill;

[0012] A conveyor belt is arranged below the fifth pipeline, and the end of the conveyor belt is connected to the magnetic separator.

[0013] Preferably, a distribution baffle group for external circulation material dispersion is arranged inside the first pipeline; the distribution baffle group includes a plurality of distribution baffles, the distribution baffles are arranged in an inclined downward manner, adjacent distribution baffles in the upward and downward directions are arranged in parallel, and adjacent distribution baffles in the left and right directions are arranged in a staggered manner.

[0014] Preferably, the magnetic field strength of the iron removal magnetic drum is 3000-5000Gs, the magnetic wrapping angle of the iron removal magnetic drum is 180°, and the cylinder linear velocity is 150-200m / min.

[0015] Preferably, a receiving plate is further arranged in the second pipeline, the receiving plate is arranged in an inclined manner and extends towards the middle area of the vibrating screen, and the receiving plate is above the fourth pipeline.

[0016] Preferably, the receiving plate is in a corrugated chute structure, including a plurality of corrugated bodies, each corrugated body includes a first strip chute plate and a second strip chute plate, and one side of the first strip chute plate and the second strip chute plate is connected; adjacent corrugated bodies are connected head to tail to form a chute.

[0017] Preferably, the screen hole size of the vibrating screen is 1-5mm.

[0018] Preferably, the third pipeline, the fifth pipeline and the sixth pipeline jointly constitute a Y-shaped pipeline, and the bottom end of the fifth pipeline and the conveyor belt are sealingly connected through a rubber sheet.

[0019] Preferably, a valve for controlling the magnitude of the negative pressure in the Y-shaped pipeline is arranged on the sixth pipeline.

[0020] Preferably, the magnetic separator is an updraft magnetic separator, the magnetic roller of which comprises a first-stage magnetic roller, a second-stage magnetic roller and a third-stage magnetic roller arranged from bottom to top; a material falling plate is arranged on one side of the updraft magnetic separator, the material falling plate is arranged obliquely, a high-quality iron particle discharge port is arranged at the top of the material falling plate, and a remaining material discharge port after magnetic separation is arranged at the bottom of the material falling plate.

[0021] Preferably, the magnetic induction intensity of the first-stage magnetic roller is 8000-10000Gs, the magnetic induction intensity of the second-stage magnetic roller is 5000-8000Gs, and the magnetic induction intensity of the third-stage magnetic roller is 3000-5000Gs.

[0022] The beneficial technical effects of the present application are as follows:

[0023] In view of the problem that the separation effect of iron particles and slag powder in the slag grinding process is poor, affecting the utilization value of iron particles and the utilization rate of slag, the present application takes the external circulation material of the vertical mill as the processing object and designs an iron separation and impurity removal device in the slag grinding external circulation process of the granulated blast furnace slag. The processing flow of the iron separation and impurity removal device includes efficient separation of iron particles and slag powder, purification of iron particles and removal of low-activity hard particles, and the main equipment is an iron separation and impurity removal chute, a vibrating screen and a three-stage magnetic separator. The device obtains high-quality iron particles from the external circulation material through two-stage separation. In addition, through the separation of the pipeline type high-frequency vibrating screen, the low-activity hard particles in the external circulation material are effectively removed, and the quality of the slag powder is improved. The processing flow of the entire iron separation and impurity removal device adopts a circulating and closed mode, and the slag powder is continuously circulated in the system until it is finally selected by the powder separator connected to the vertical mill. The design not only improves the recovery rate and quality of the slag, but also greatly improves the purity of the iron particles. The present application also has the advantages of simple processing flow, low equipment operation and maintenance cost, effectively reduces the wear of the iron particles on the grinding disc and grinding roller of the vertical mill, and prolongs the service life of the vertical mill. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a whole structure principle schematic view of the iron separation and impurity removal device in the slag grinding process of the granulated blast furnace slag of the present application;

[0025] Figure 2 It is a structure principle schematic view of the iron separation and impurity removal chute in the device of the present application;

[0026] Figure 3 It is a structure schematic view of the material receiving plate in the device of the present application;

[0027] Figure 4The utility model discloses a fifth pipeline and the connection schematic diagram of conveying belt in the device.

[0028] In the drawing: 1 - vertical mill, 2 - bucket elevator, 3 - iron-removing chute, 4 - iron-removing magnetic drum, 5 - material receiving plate, 6 - vibrating screen, 7 - conveying belt, 8 - rubber sheet, 9 - magnetic separator, 10 - material dropping plate, 11 - high-quality iron particle outlet, 12 - residual material outlet after magnetic separation;

[0029] 301 - first pipeline, 302 - second pipeline, 303 - third pipeline, 304 - fourth pipeline, 305 - fifth pipeline, 306 - sixth pipeline, 307 - valve; 3011 - cloth baffle;

[0030] 501 - corrugated body, 502 - chute;

[0031] 901 - first-stage magnetic roller, 902 - second-stage magnetic roller, 903 - third-stage magnetic roller. DETAILED DESCRIPTION

[0032] The utility model discloses a slag in the vertical mill external circulation process as the processing object, and designs a kind of iron-removing device in the granulated blast furnace slag powder grinding external circulation process, and the main treatment process of this device includes the efficient separation of iron particle and slag powder, the purification of iron particle and the removal of low-activity hard particle, and main equipment is iron-removing chute, high-frequency vibrating screen and three-stage magnetic separator.Based on the iron-removing device proposed in the utility model, iron particle and low-activity hard particle in vertical mill external circulation material can be effectively separated, and the quality of iron particle is effectively improved by increasing a purification process, and the loss rate of slag is reduced.

[0033] As Figure 1 As shown in a kind of iron-removing device in the granulated blast furnace slag powder grinding process, including iron-removing chute 3 and magnetic separator 9, vertical mill 1 is connected with iron-removing chute 3 by bucket elevator 2. As Figure 2 As shown, the iron-removing chute 3 includes first pipeline 301, second pipeline 302 and third pipeline 303, first pipeline 301 is vertically arranged, and second pipeline 302 and third pipeline 303 are bifurcatedly connected at the bottom end of first pipeline 301, and iron-removing magnetic drum 4 is arranged at the connection of first pipeline 301, second pipeline 302 and third pipeline 303.In second pipeline 302, vibrating screen 6 is arranged, and fourth pipeline 304 is further connected at the position above vibrating screen 6.The end of third pipeline 303 is connected with fifth pipeline 305 and sixth pipeline 306, fifth pipeline 305 is vertically arranged, and third pipeline 303 and sixth pipeline 306 are bifurcatedly connected at the top end of fifth pipeline 305, and sixth pipeline 306 is connected to vertical mill 1.Conveying belt 7 is arranged below fifth pipeline 305, and the end of conveying belt 7 is connected with magnetic separator 9.

[0034] The device obtains high-quality iron particles from the external circulating material through two-stage separation.

[0035] As a further design of the utility model, a cloth baffle group is arranged in the first pipeline 301; the cloth baffle group comprises a plurality of cloth baffles 3011, the cloth baffles 3011 are arranged in a downward oblique manner, the upper and lower adjacent cloth baffles are arranged in parallel, and the left and right adjacent cloth baffles are arranged in a staggered manner. This arrangement can be used for uniform dispersion of the external circulating material.

[0036] The magnetic field strength of the iron removal magnetic drum 4 is 3000-5000Gs, the magnetic wrap angle of the iron removal magnetic drum is 180°, and the linear speed of the drum is 150-200 m / min.

[0037] Further, a receiving plate 5 is arranged in the second pipeline 302, the receiving plate 5 is arranged in an inclined manner and extends towards the middle area of the vibrating screen 6, and the receiving plate 5 is above the fourth pipeline 304. As shown in Figure 3 The receiving plate is in a corrugated chute structure, comprising a plurality of corrugated bodies 501, each corrugated body comprises a first strip chute and a second strip chute, and the side edges of the first strip chute and the second strip chute are connected. The adjacent corrugated bodies are connected at the head and tail to form a chute 502. The screen size of the vibrating screen is 1-5 mm.

[0038] Further, the third pipeline 303, the fifth pipeline 305 and the sixth pipeline 306 jointly constitute a Y-shaped pipeline, and the bottom end of the fifth pipeline 305 is sealingly connected with the conveying belt through a rubber sheet 8, as shown in Figure 4 A valve 307 for controlling the size of negative pressure in the Y-shaped pipeline is arranged on the sixth pipeline 306.

[0039] Further, the magnetic separator adopts an upper suction type magnetic separator, the magnetic roller comprises a first-stage magnetic roller 901, a second-stage magnetic roller 902 and a third-stage magnetic roller 903 arranged from bottom to top. A material falling plate 10 is arranged on one side of the upper suction type magnetic separator, the material falling plate is arranged in an inclined manner, a high-quality iron particle discharge port 11 is arranged at the top of the material falling plate 10, and a residual material discharge port 12 after magnetic separation is arranged at the bottom of the material falling plate 10.

[0040] The magnetic induction intensity of the first-stage magnetic roller 901 is 8000-10000Gs, the magnetic induction intensity of the second-stage magnetic roller 902 is 5000-8000Gs, and the magnetic induction intensity of the third-stage magnetic roller 903 is 3000-5000Gs.

[0041] The working process of the utility model will be described in detail as follows:

[0042] The slag raw material is first subjected to grid impurity removal and pre-grinding iron removal, and is ground in the vertical mill 1. After being ground and dried in the vertical mill 1, the particles reaching the qualified fineness are selected out by the high-efficiency powder separator connected with the vertical mill, and are collected as qualified products. The coarse particle material in the vertical mill 1 falls under the action of centrifugal force into the lower part of the vertical mill 1, and enters the bucket elevator 2 as external circulation material.

[0043] (1) One-stage separation of iron particles in the external circulation material;

[0044] The bucket elevator 2 is connected with the iron-removal impurity removal chute 3, as shown in Figure 2 The iron-removal impurity removal chute 3 includes a first pipeline 301, a second pipeline 302 and a third pipeline 303. The first pipeline 301 is arranged vertically, and the second pipeline 302 and the third pipeline 303 are bifurcatedly connected at the bottom end of the first pipeline 301. The iron-removal magnetic drum 4 or the magnetic drum type iron remover is arranged at the connection of the first pipeline 301, the second pipeline 302 and the third pipeline 303.

[0045] A distribution baffle group for dispersing the external circulation material is arranged in the inside of the first pipeline 301. The distribution baffle group includes a plurality of distribution baffles 3011. The distribution baffles are arranged in a downwardly inclined manner. Adjacent distribution baffles in the up-down direction are arranged in parallel, and adjacent distribution baffles in the left-right direction are arranged in a staggered manner.

[0046] The external circulation material enters the iron-removal impurity removal chute 3 through the first pipeline 301. The distribution baffles 3011 are arranged in the first pipeline 301 for dispersing the external circulation material, so that the distribution of the external circulation material is more uniform. An iron-removal magnetic drum 4 is installed at the end of the first pipeline 301, which mainly functions to perform one-stage separation of the iron particles in the external circulation material.

[0047] The magnetic field strength of the iron-removal magnetic drum 4 is 3000-5000Gs, and is preferably 3500-4500Gs. The function is to separate the iron particles in the external circulation material. The magnetic wrap angle of the iron-removal magnetic drum 4 is 180°, and the cylinder linear speed is 150-200m / min, and is preferably 160-180m / min, so that the iron-rich material and the mixed mineral powder are as much as possible to be thrown away from the surface of the cylinder by the centrifugal force. After the external circulation material is separated by the iron-removal magnetic drum 4, the obtained iron-removal material falls into the second pipeline 302, and the iron-rich material falls into the third pipeline 303.

[0048] (2) One-stage recovery of slag powder in the external circulation material and removal of low-activity hard particles;

[0049] The de-ironed material obtained after the external circulation material is separated by the de-ironing magnetic drum 4 falls into the second pipeline 302. The second pipeline 302 is connected with the fourth pipeline 304, and a material receiving plate 5 is arranged above the connection position, and a vibrating screen 6 is arranged below the connection position. The material receiving plate 5 is arranged in an inclined manner and extends towards the middle region of the vibrating screen and is arranged above the fourth pipeline. As shown in Figure 3 , the material receiving plate is designed as a corrugated chute structure and comprises a plurality of corrugated bodies 501, each of which comprises a first strip chute plate and a second strip chute plate, and the first strip chute plate and the second strip chute plate are connected at one side. The adjacent corrugated bodies are connected in a head-to-tail manner to form a chute 502. In this way, the de-ironed material in the second pipeline 302 can be uniformly fed into the vibrating screen 6 through the material receiving plate 5. The vibrating screen 6 can vibrate at a high frequency, and the screen hole size is 1-5 mm, preferably 2-3 mm. After the de-ironed material is screened by the vibrating screen 6, the slag powder falls into the lower part of the second pipeline 302 and returns to the vertical mill 1, and the low-activity hard particles enter the fourth pipeline 304 from the screen and are discharged from the external circulation, so that the slag powder in the external circulation material is recovered in one stage and the low-activity hard particles are removed.

[0050] (3) Two-stage recovery of slag powder in the external circulation material;

[0051] After the external circulation material is separated by the de-ironing magnetic drum 4, the iron-rich material falls into a Y-shaped pipeline composed of a third pipeline 303, a fifth pipeline 305 and a sixth pipeline 306. When the external circulation material passes through the de-ironing magnetic drum 4, due to the large amount of slag powder, the iron particles will carry part of the non-magnetic slag powder during iron separation, resulting in loss of slag powder and reducing the quality of iron particles. Therefore, the slag powder two-stage recovery process is designed for the iron-rich material. The specific mode is as follows:

[0052] The third pipeline 303, the fifth pipeline 305 and the sixth pipeline 306 form a Y-shaped pipeline, the end of the third pipeline 303 is connected with the fifth pipeline 305 and the sixth pipeline 306, the fifth pipeline 305 is arranged vertically, the third pipeline 303 and the sixth pipeline 306 are bifurcatedly connected at the top end of the fifth pipeline 305, and the sixth pipeline 306 is connected to the vertical mill. The slag powder carried in the iron-rich material is sucked back to the vertical mill 1 by the negative pressure in the vertical mill 1. In order to ensure that a stable negative pressure is formed in the Y-shaped pipeline, the fifth pipeline 305 is connected with the conveying belt 4 by a rubber sheet 8, and a closed or semi-closed state is formed by the accumulation of the material, as shown in Figure 4 , so as to realize the two-stage recovery of the slag powder in the iron-rich material. The sixth pipeline 306 is provided with a valve 307, and by changing the opening degree of the valve 307, the size of the negative pressure in the Y-shaped pipeline is controlled, and the recovery rate of the slag powder is adjusted.

[0053] (4) Purification of the iron-rich material in the external circulation material and three-stage recovery of slag powder;

[0054] After the second stage recovery of slag powder in the Y-shaped pipeline, the remaining iron-rich material falls into the conveyor belt 7 through the fifth pipeline 305, and then is transported to the third-stage magnetic separator 9. The third-stage magnetic separator 9 is an upward-suction magnetic separator, and the magnetic rollers are arranged from bottom to top in a first-stage, second-stage and third-stage structure. The magnetic induction intensity of the first-stage magnetic roller 901 is 8000-10000Gs, the magnetic induction intensity of the second-stage magnetic roller 902 is 5000-8000Gs, and the magnetic induction intensity of the third-stage magnetic roller 903 is 3000-5000Gs.

[0055] The design of three-stage magnetic separation with gradually decreasing magnetic roller induction intensity can effectively guarantee the quality of iron particles, realize three-stage recovery of slag powder, and avoid dust problems when iron particles are discharged. The high-quality iron particles after the third-stage magnetic separation can be directly recycled, and the remaining material is returned to the iron removal chute 3 through the bucket elevator 2 for recycling.

[0056] The utility model discloses a two-stage separation mode from the external circulation material obtains high-quality iron particles. Through the separation of the pipeline type high-frequency vibrating screen, the low-activity hard particles in the external circulation material are effectively removed, and the quality of slag powder is improved. The whole iron removal process adopts a closed mode, and the slag powder is continuously circulated in the system until finally selected by the powder separator connected with the vertical mill. The design not only improves the recovery rate and quality of slag, but also greatly improves the purity of iron particles.

Claims

1. An iron beneficiation and impurity removal device for the granulation blast furnace slag grinding process, characterized in that: The vertical mill is connected to the iron ore separation and impurity removal chute and the magnetic separator via a bucket elevator. The iron selection and impurity removal chute includes a first pipe, a second pipe, and a third pipe. The first pipe is arranged vertically, and the second and third pipes are bifurcated and connected to the bottom of the first pipe. An iron removal magnetic drum is installed at the connection of the first, second, and third pipes. A vibrating screen is installed on the second pipe, and a fourth pipe is also connected to the second pipe and above the vibrating screen. The third pipe is connected to the fifth and sixth pipes at its end. The fifth pipe is arranged vertically. The third and sixth pipes are bifurcated and connected at the top of the fifth pipe. The sixth pipe is connected to the vertical mill. A conveyor belt is installed below the fifth pipe, and the end of the conveyor belt is connected to a magnetic separator.

2. The iron removal and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: Inside the first pipe, there is a material distribution baffle assembly for dispersing external circulating materials; the material distribution baffle assembly includes several material distribution baffles, which are arranged to extend downwards at an angle, with adjacent material distribution baffles arranged in parallel and adjacent material distribution baffles arranged in an alternating manner.

3. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: The magnetic field strength of the iron removal magnetic drum is 3000-5000 Gs, the magnetic wrap angle of the iron removal magnetic drum is 180°, and the drum linear speed is 150-200 m / min.

4. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: A receiving plate is also installed inside the second pipe. The receiving plate is arranged at an angle and extends toward the middle area of ​​the vibrating screen. The receiving plate is located above the fourth pipe.

5. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 4, characterized in that: The receiving plate has a corrugated chute structure, comprising several corrugated bodies. Each corrugated body includes a first strip slide and a second strip slide, with one side of the first strip slide and the second strip slide connected together. Adjacent corrugated bodies are connected end to end to form a chute.

6. The iron ore beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: The screen aperture size of the vibrating screen is 1-5 mm.

7. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: The third, fifth, and sixth pipes together form a Y-shaped pipe, with the bottom end of the fifth pipe sealed to the conveyor belt by a rubber sheet.

8. The iron ore beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 7, characterized in that: A valve is installed on the sixth pipe to control the amount of negative pressure in the Y-shaped pipe.

9. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 1, characterized in that: The magnetic separator is an upward suction type magnetic separator, and its magnetic rollers include a first-stage magnetic roller, a second-stage magnetic roller, and a third-stage magnetic roller arranged from bottom to top; a discharge plate is provided on one side of the upward suction type magnetic separator, the discharge plate is arranged at an inclination, a high-quality iron particle discharge port is provided at the top of the discharge plate, and a discharge port for the remaining material after magnetic separation is provided at the bottom of the discharge plate.

10. The iron beneficiation and impurity removal device in the granulation blast furnace slag grinding process according to claim 9, characterized in that: The magnetic induction intensity of the first-stage magnetic roller is 8000-10000 Gs, the magnetic induction intensity of the second-stage magnetic roller is 5000-8000 Gs, and the magnetic induction intensity of the third-stage magnetic roller is 3000-5000 Gs.

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