Low-grade magnesite ore washing grading system

Abstract

The invention belongs to the technical field of metallurgical equipment installation, and particularly relates to a low-grade magnesite ore washing grading system which is characterized in that a grading conveyor I and / or a grading conveyor II are / is arranged on a variable-dip-angle rack and comprise a horizontal section, a variable-angle section and a linear section in the length direction; the end point of the linear section is positioned on the discharging side, and a base frame is arranged at the bottom of the linear section; the base frame of the angle changing section is of a multi-section hinged structure, the adjacent base frames are connected through hinged bolts, the conveying angle of any section of the angle changing section is not larger than the repose angle of ore, and at least one of the middle rollers of the angle changing section is a power roller. The inclination angle belt conveyor has the advantages that the inclination angle belt conveyor adopts the base frame of the multi-section hinged structure, the angle of the belt conveyor is adjusted more flexibly, and safety accidents caused by ore accumulation and collapse due to the fact that the local inclination angle is too large are avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical equipment installation, and in particular relates to a low-grade magnesite ore washing and grading system. Background Art

[0002] Magnesite is a carbonate mineral with high industrial value. It is the main source of magnesium. When a solution containing magnesium acts on calcite, it will turn calcite into magnesite. Therefore, magnesite also belongs to the calcite family. Magnesite crystals belong to the trigonal carbonate minerals, usually in the form of grains or cryptocrystalline dense blocks. The latter is also called porcelain magnesite, which is white or grayish white. The iron-containing ones are yellow to brown and have a glassy luster. The composition of magnesite is mainly MgCO3, and iron and manganese often replace magnesium, but the iron content of natural magnesite is generally not high. Magnesite has complete rhombohedral cleavage, while porcelain magnesite has a shell-like fracture. Magnesite often contains iron, which is the result of iron or manganese replacing magnesium.

[0003] After years of mining, high-grade magnesite can no longer meet production needs, and low-grade magnesite also contains some gangue minerals such as dolomite and quartz. The main purpose of magnesite beneficiation is to remove gangue minerals to remove impurities such as CaO and SiO2, and obtain high-purity MgO. Dolomite is the main calcium-containing impurity mineral in magnesite. Its presence will cause the formation of CaSiO3 during the subsequent high-temperature calcination process, which is easy to loosen after cooling and affects the properties of light-burned magnesium oxide. Dolomite and magnesite are both carbonate minerals, with exactly the same anions and partially the same cations. Their crystal structures and surface properties are very similar, and it is very difficult to separate them by flotation. Therefore, the comprehensive utilization of high-calcium, high-silicon, low-grade magnesite containing gangue minerals such as dolomite and quartz is a global problem, especially in magnesite, the effective removal of dolomite and quartz in industry needs to be further solved.

[0004] The Chinese invention patent with application number 201910247353.4 discloses a method for preparing high-purity light-burned magnesium oxide by calcining low-grade magnesite to decalcify and remove silicon. The low-grade magnesite containing dolomite and quartz is cleaned and crushed. The magnesite powder with a particle size of 2.5 to 20 mm is calcined at 600 to 700°C for 1 to 2.5 hours to obtain a mixture of decomposed magnesite, dolomite and quartz, and then selectively ground to obtain a grinding product; screening and grading are performed to obtain a grinding product with a particle size of -0.074 mm; the magnesite powder with a particle size of 0.1 to 2.5 mm is placed in a suspension furnace for air calcination, calcined at 570 to 670°C for 0.5 to 2 hours, and light-burned magnesium recovered by suspension calcination is obtained; the light-burned magnesium is then air-selected and purified to finally prepare a high-purity light-burned magnesium product.

[0005] The Chinese invention patent with application number 202010795172.8 discloses a method for screening magnesite with low silica content, comprising the following steps: 1) cleaning of magnesite: using low-grade magnesite as raw material, cleaning, and removing mud and fine-grained minerals on its surface; 2) grinding of magnesite: grinding the magnesite after cleaning in step 1) to obtain mineral powder; 3) pulping of magnesite: adding water to the mineral powder after grinding in step 2), mixing evenly to prepare slurry; 4) flotation of magnesite: sending the slurry after pulping in step 3) to the flotation equipment for reverse flotation to obtain concentrate powder; 5) drying of magnesite: washing the concentrate powder after flotation in step 4) with water, and then drying.

[0006] The existing belt conveyor conducts diversion and transportation of the screened materials. Due to the structural limitations of the belt conveyor, in order to obtain a sufficient conveying height, the belt conveyor needs to be configured to be 25 meters long, which occupies a large area. Summary of the invention

[0007] The purpose of the present invention is to provide a low-grade magnesite ore washing and grading system, overcome the shortcomings of the prior art, adopt a variable inclination belt conveyor to divert and convey the screened materials, shorten the length of the belt conveyor, and reduce the floor space of the production line; the inclined belt conveyor adopts a multi-section hinged structure base frame, which makes the angle adjustment of the belt conveyor more flexible, avoiding excessive local inclination angles, causing ore accumulation and collapse and causing safety accidents.

[0008] To achieve the above object, the present invention is implemented through the following technical solutions:

[0009] The low-grade magnesite ore washing and grading system comprises a vibrating screen, a grading conveyor 1, a grading conveyor 2, a sorting conveyor and a cleaning and impurity removal bin, wherein a feed bin is arranged at the inlet of the vibrating screen, an outlet for the material on the screen is located at the feeding side of the grading conveyor 1, an outlet for the material under the screen is located at the feeding side of the grading conveyor 2, the discharge side of the grading conveyor 1 is located above the inlet of the cleaning and impurity removal bin, and the bottom outlet of the cleaning and impurity removal bin is located at the feeding side of the sorting conveyor; the upper and lower water of the cleaning and impurity removal bin are respectively connected to the circulating water system through pipelines, and the grading conveyor 1 and / or the grading conveyor 2 are ..., and the grading conveyor 1 and / or the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and / or the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and the grading conveyor 2 are connected to the circulating water system, and the grading conveyor 1 and the grading conveyor 2 are connected to the circulating water system, and the The conveyor 2 is respectively arranged on a variable inclination frame. The grading conveyor 1 and / or the grading conveyor 2 includes a horizontal section, a variable angle section and a straight section along the length direction. The horizontal section is located on the feeding side, and the end point of the straight section is located on the discharging side. A base frame is provided at the bottom, and an intermediate roller is provided in the center of the top of the base frame. A left roller and a right roller are provided on both sides of the intermediate roller, and a return roller is provided below the intermediate roller. The base frame of the variable angle section is a multi-section hinged structure, and adjacent base frames are connected by hinge bolts, so that the conveying angle of any section in the variable angle section is not greater than the repose angle of the ore, and at least one of the intermediate rollers of the variable angle section is a power roller.

[0010] Furthermore, the discharge elevation of the grading conveyor 1 is 4.5 meters, and the elevation angle of the grading conveyor 1 is 15-16°; the discharge side elevation of the grading conveyor 2 is 4.8 meters, and the elevation angle of the grading conveyor 2 is 18-19°.

[0011] Furthermore, the variable inclination angle frame is a steel frame or a concrete platform.

[0012] Furthermore, the vibrating screen is a linear vibrating screen, the screen surface is installed at an inclination angle of 8°, the screen surface is suspended, and two vibration motors are arranged on a bracket above the screen surface.

[0013] Furthermore, the arc radius of the variable inclination frame of the variable angle section is 30-35 meters.

[0014] Furthermore, the base frame includes a longitudinal beam, a column and a return roller bracket, the front and rear ends of the longitudinal beam are respectively provided with hinged ear plates, the upper end of the column is hinged to the longitudinal beam, the relative angle between the column and the longitudinal beam is adjusted by an arc-shaped positioning plate, one end of the arc-shaped positioning plate is connected to the longitudinal beam by bolts, and the other end of the arc-shaped positioning plate is hinged to the column by bolts; the return roller bracket is provided with a return roller.

[0015] Furthermore, the power roller includes a roller body, a reducer, a sprocket and a chain. Sprocket one is provided at one end of the roller body, and sprocket two is provided at the shaft end of the reducer. Sprocket one and sprocket two are meshed and connected by a chain. The roller body is a composite rubber roller with a friction coefficient of 0.4-0.55.

[0016] Furthermore, two return rollers are symmetrically arranged on the return roller bracket, the center line angle of the two return rollers is 120-150 degrees, and a plurality of rubber rings are arranged in parallel on the surface of the return roller.

[0017] Furthermore, a suspended vibrating chute is provided at the bottom outlet of the cleaning and impurity removal bin.

[0018] Furthermore, the suspended vibrating chute includes a chute, a vibrating feeder and a hanging part, one end of the chute is located below the bottom outlet of the cleaning and impurity removal bin, the other end of the chute is located above the feeding side of the sorting conveyor, one end of the chute is connected to the vibrating feeder, the chute and the vibrating feeder are respectively connected to the shelf of the cleaning and impurity removal bin through hanging parts, when ore falls on the chute, the chute presents an inclination angle of 8-15° toward the outlet side.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) Use a variable-angle belt conveyor to divert and convey the screened materials. At the same conveying height, the length of the belt conveyor is shortened to 20 meters, which effectively reduces the floor space of the production line and reduces investment costs.

[0021] 2) The variable inclination belt conveyor adopts a multi-section hinged structure frame, which makes the angle adjustment of the belt conveyor more flexible, avoiding excessive local inclination angles, resulting in ore accumulation and collapse, causing safety accidents;

[0022] 3) The ore is graded before cleaning, and the ore with a particle size of 12-30 mm is centrally cleaned in the cleaning and impurity removal bin to improve the subsequent sorting effect and the efficiency and effect of ore extraction and processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic top view of the structure of an embodiment of the present invention;

[0024] Figure 2 yes Figure 1 Sectional view along line AA;

[0025] Figure 3 yes Figure 1 Sectional view along line BB;

[0026] Figure 4 Schematic diagram of the variable inclination frame structure of the variable angle section II in an embodiment of the present invention;

[0027] Figure 5 yes Figure 4 Sectional view along CC line;

[0028] Figure 6 is a schematic diagram of a base frame structure in an embodiment of the present invention;

[0029] Figure 7 is a schematic diagram of the connection of multiple base frames in the variable angle section II in an embodiment of the present invention;

[0030] Figure 8 2 is a schematic diagram of the structure of the cleaning and impurity removal bin in an embodiment of the present invention;

[0031] Fig. 9 Schematic diagram of the structure of the linear vibrating screen in an embodiment of the present invention.

[0032] In the figure: 1-linear vibrating screen, 2-grading conveyor 1, 3-grading conveyor 2, 4-sorting conveyor, 5-cleaning and impurity removal bin, 6-feeding bin, 7-base frame, 8-middle roller, 9-left roller, 10-right roller, 11-return roller, 12-hinge bolt, 13-suspended vibrating chute, 14-slide trough, 15-vibrating feeder, 16-suspension part, 17-roller body, 18-reducer, 19-sprocket 1, 20-sprocket 2, 21-chain, 22-longitudinal beam, 23-variable inclination frame, 24-water collecting trough, 25-column, 26-return roller bracket, 27-arc positioning plate, 28-hinge ear plate. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0034] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the specific embodiments required to be used in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some implementation methods of the present invention. For ordinary technicians in this field, other specific embodiments can be obtained based on these specific embodiments without paying creative work.

[0035] The components of the embodiments of the present invention generally described and shown in the specific embodiments herein can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the invention claimed, but only represents selected embodiments of the present invention.

[0036] See Figure 1-3 , is a schematic diagram of an embodiment of a low-grade magnesite ore washing and grading system of the present invention, comprising a linear vibrating screen 1, a grading conveyor 1 2, a grading conveyor 2 3, a sorting conveyor 4, a cleaning and impurity removal bin 5 and a circulating water system. A feed bin 6 is provided at the inlet of the linear vibrating screen 1, an outlet for upper material of the screen is located on the feeding side of the grading conveyor 1 2, an outlet for lower material of the screen is located on the feeding side of the grading conveyor 2 3, a discharge side of the grading conveyor 1 2 is located above the inlet of the cleaning and impurity removal bin 5, and a bottom outlet of the cleaning and impurity removal bin 5 is located on the feeding side of the sorting conveyor 4; the upper water and lower water of the cleaning and impurity removal bin 5 are respectively connected to the circulating water system through pipelines.

[0037] The discharge elevation of grading conveyor 1-2 is 4.5 meters, and the maximum elevation angle of grading conveyor 1-2 is 15°47'. The discharge side elevation of grading conveyor 2-3 is 4.8 meters, and the maximum elevation angle of grading conveyor 2-3 is 18°36'. The specification of grading conveyor 1-2 is B650 belt conveyor, belt speed 1.25m / s, and the specification of grading conveyor 2-3 is B650 belt conveyor, belt speed 1.20m / s, and the maximum elevation angle is 15°. The specification of sorting conveyor 4 is B800 belt conveyor, belt speed 0.20m / s, which is a parallel belt hand-selected conveyor, and can also be used in conjunction with various artificial intelligence sorting machines.

[0038] See Figure 4-5The grading conveyor 1 2 and the grading conveyor 2 3 are respectively arranged on a variable inclination frame 23, and the variable inclination frame 23 is a steel frame or a concrete platform. The grading conveyor 1 2 and the grading conveyor 2 3 include a horizontal section I, a variable angle section II and a straight section III along the length direction. The horizontal section I is located on the feeding side, and the end of the straight section III is located on the discharging side. A base frame 7 is provided at the bottom, and an intermediate roller 8 is provided in the center of the top of the base frame. A left roller 9 and a right roller 10 are provided on both sides of the intermediate roller 8, and a return roller 11 is provided below the intermediate roller 8.

[0039] See Figure 6 The base frame 7 includes a longitudinal beam 22, a column 25 and a return roller bracket 26. The front and rear ends of the longitudinal beam 22 are respectively provided with hinged ear plates 28. The upper end of the column 25 is hinged to the longitudinal beam 22. The relative angle between the column 25 and the longitudinal beam 22 is adjusted by an arc-shaped positioning plate 27. One end of the arc-shaped positioning plate 27 is connected to the longitudinal beam 22 by bolts, and the other end of the arc-shaped positioning plate 27 is hinged to the column 25 by bolts. The return roller bracket 26 is provided with a return roller 11. The return roller bracket 26 is provided with two return rollers symmetrically on the left and right, and the center line angle of the two return rollers is 120-150°. A plurality of rubber rings are provided in parallel on the surface of the return roller 11.

[0040] At least one of the intermediate rollers 8 of the variable angle section II is a power roller, which includes a roller body 17, a reducer 18, a sprocket and a chain. A sprocket 19 is provided at one end of the roller body 17, and a sprocket 20 is provided at the shaft end of the reducer 18. The sprocket 19 and the sprocket 2 20 are meshed and connected by a chain 21. The roller body 17 is a composite rubber roller with a friction coefficient of 0.4-0.55.

[0041] See Figure 7 , a schematic diagram of the connection of multiple base frames in the variable angle section II, the arc radius of the variable angle frame of the variable angle section II is 30 meters. The base frame of the variable angle section II is a multi-section hinged structure, and adjacent base frames are connected by hinge bolts 12, so that the conveying angle of any section in the variable angle section is not greater than the repose angle of the ore.

[0042] See Figure 8 , a suspended vibrating chute 13 is provided at the bottom outlet of the cleaning and impurity removal bin 5, and a water collecting trough 24 is provided below the suspended vibrating chute 13. The suspended vibrating chute includes a chute 14, a vibrating feeder 15 and a suspension 16. One end of the chute 14 is located below the bottom outlet of the cleaning and impurity removal bin 5, and the other end of the chute 14 is located above the feeding side of the sorting conveyor 4. One end of the chute 14 is connected to the vibrating feeder 15. The chute 14 and the vibrating feeder 15 are respectively connected to the shelf of the cleaning and impurity removal bin 5 through the suspension 16. The suspension 16 is an elastic suspension with a compression spring inside. When ore falls on the chute 14, the chute 14 presents an 8-15° inclination angle to the outlet side to facilitate the discharge of the ore. The specification of the vibrating feeder 15 is a GZ6 motor vibrating feeder.

[0043] See Fig. 9 The screen surface of the linear vibrating screen 1 is installed at an inclination angle of 8°, the screen surface is suspended, two vibration motors are installed on the bracket above the screen surface, and the screen hole diameter is 12mm×12mm. The particle size of the material on the screen is 12-30mm, and the particle size of the material under the screen is less than 12mm.

[0044] When the present invention is working, the loader feeds the ore from the feed bin 6 to the linear vibrating screen 1, and the linear vibrating screen 1 screens the ore into an oversize part with a size of more than 12 mm and an undersize part with a size of less than 12 mm. The oversize part goes on a grading conveyor 1 2, and the undersize part goes on a grading conveyor 2 3. Both the grading conveyor 1 2 and the grading conveyor 2 3 are along a variable inclination frame 23, and their discharge ports reach an elevation of more than 4.5 meters. The terminal of the grading conveyor 2 3 is a fine material yard, and the terminal of the grading conveyor 1 2 is a cleaning and impurity removal bin 5. After the ore is fully cleaned by the spray pipe, the dolomite and quartz powder in the low-grade magnesite are washed away by water, enter the sedimentation tank 17, and are deposited at the bottom of the sedimentation tank 17. After the wash water is clarified, it enters the circulation tank 18 from the upper edge of the overflow weir 19 and is pumped back to the cleaning and impurity removal bin 5 by the submersible pump 20.

[0045] Magnesite is normally granular or cryptocrystalline dense block, white or off-white, yellow to brown with iron, glassy luster, with complete rhombohedral cleavage, and porcelain magnesite has shell-like fracture. After being fully cleaned, magnesite is very easy to be sorted out by manual or artificial intelligence sorting machines, so as to achieve the purification of low-grade (poor) magnesite and facilitate the further application of magnesite.

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-grade magnesite ore washing and grading system, comprising a vibrating screen, a grading conveyor 1, a grading conveyor 2, a sorting conveyor and a cleaning and impurity removal bin, wherein a feed bin is provided at the inlet of the vibrating screen, an outlet for the material on the screen is located at the feeding side of the grading conveyor 1, an outlet for the material under the screen is located at the feeding side of the grading conveyor 2, a discharge side of the grading conveyor 1 is located above the inlet of the cleaning and impurity removal bin, and a bottom outlet of the cleaning and impurity removal bin is located at the feeding side of the sorting conveyor; the water supply and discharge of the cleaning and impurity removal bin are respectively connected to a circulating water system through pipelines, and the invention is characterized in that: The grading conveyor 1 and / or the grading conveyor 2 are respectively arranged on a variable inclination frame, and the grading conveyor 1 and / or the grading conveyor 2 include a horizontal section, a variable angle section and a straight section along the length direction, the horizontal section is located on the feeding side, and the end point of the straight section is located on the discharging side, and a base frame is provided at the bottom, and an intermediate roller is provided in the center of the top of the base frame, and a left roller and a right roller are provided on both sides of the intermediate roller, and a return roller is provided below the intermediate roller; the base frame of the variable angle section is a multi-section hinged structure, and adjacent base frames are connected by hinge bolts, so that the conveying angle of any section in the variable angle section is not greater than the repose angle of the ore, and at least one of the intermediate rollers of the variable angle section is a power roller.

2. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The discharge elevation of the grading conveyor 1 is 4.5 meters, and the elevation angle of the grading conveyor 1 is 15-16°; the discharge side elevation of the grading conveyor 2 is 4.8 meters, and the elevation angle of the grading conveyor 2 is 18-19°.

3. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The variable inclination angle frame is a steel frame or a concrete platform.

4. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The vibrating screen is a linear vibrating screen, the screen surface is installed at an inclination angle of 8°, the screen surface is suspended, and two vibration motors are arranged on a bracket above the screen surface.

5. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The arc radius of the variable inclination frame of the variable angle section is 30-35 meters.

6. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The base frame includes a longitudinal beam, a column and a return roller bracket, the front and rear ends of the longitudinal beam are respectively provided with hinged ear plates, the upper end of the column is hinged to the longitudinal beam, the relative angle between the column and the longitudinal beam is adjusted by an arc-shaped positioning plate, one end of the arc-shaped positioning plate is connected to the longitudinal beam by bolts, and the other end of the arc-shaped positioning plate is hinged to the column by bolts; the return roller bracket is provided with a return roller.

7. The low-grade magnesite ore washing and grading system according to claim 1 is characterized in that: The power roller includes a roller body, a reducer, a sprocket and a chain. Sprocket one is provided at one end of the roller body, and sprocket two is provided at the shaft end of the reducer. Sprocket one and sprocket two are meshed and connected by a chain. The roller body is a composite rubber roller with a friction coefficient of 0.4-0.

55.

8. The low-grade magnesite ore washing and grading system according to claim 6, characterized in that: The return roller bracket is provided with two return rollers symmetrically on the left and right, the center line angle of the two return rollers is 120-150 degrees, and a plurality of rubber rings are provided in parallel on the surface of the return roller.

9. The low-grade magnesite ore washing and grading system according to claim 1, characterized in that: A suspended vibrating chute is provided at the bottom outlet of the cleaning and impurity removal bin.

10. The low-grade magnesite ore washing and grading system according to claim 9, characterized in that: The suspended vibrating chute includes a chute, a vibrating feeder and a hanging part. One end of the chute is located below the bottom outlet of the cleaning and impurity removal bin, and the other end of the chute is located above the feeding side of the sorting conveyor. One end of the chute is connected to the vibrating feeder. The chute and the vibrating feeder are respectively connected to the shelf of the cleaning and impurity removal bin through hanging parts. When ore falls on the chute, the chute presents an inclination angle of 8-15° toward the outlet side.

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