Low-grade magnesite ore washing grading system

Abstract

The utility model 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 respectively arranged on a variable-dip-angle rack; the first grading conveyor and / or the second grading conveyor comprise / comprises a horizontal section, a variable-angle section and a linear section in the length direction, the horizontal section is located on the feeding side, the end point of the linear section is located 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 with a 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 overlarge local inclination angle are avoided.

Description

Technical Field

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

[0002] Magnesite is a carbonate mineral with high industrial value and a dominant mineral resource in my country. It is the main source of magnesium. When a solution containing magnesium acts on calcite, it converts calcite into magnesite, so magnesite also belongs to the calcite family. Magnesite crystals belong to the trigonal carbonate mineral system and are usually granular or cryptocrystalline, dense blocks. The latter is also called porcelain magnesite, which is white or off-white. Iron-containing ones are yellow to brown and have a glassy luster. Magnesite is mainly composed of MgCO3, and iron and manganese often replace magnesium. However, the iron content of natural magnesite is generally not high. Magnesite has a complete rhombohedral cleavage, while porcelain magnesite has a conchoidal 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. Low-grade magnesite also contains gangue minerals such as dolomite and quartz. Magnesite beneficiation primarily removes these gangue minerals to remove impurities such as CaO and SiO₂, yielding high-purity MgO. Dolomite is the primary calcium-containing impurity in magnesite. Its presence leads to the formation of CaSiO₃ during subsequent high-temperature calcination, which readily dissociates upon cooling and affects the properties of light-burned magnesia. Dolomite and magnesite are both carbonate minerals, sharing identical anions and some of the same cations. Their crystal structures and surface properties are very similar, making flotation separation extremely difficult. Therefore, the comprehensive utilization of low-grade, high-calcium, high-silicon magnesite containing gangue minerals such as dolomite and quartz is a global challenge. In particular, the effective industrial removal of dolomite and quartz from magnesite remains a challenge.

[0004] Chinese invention patent 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. The mixture is selectively ground to obtain a grinding product; the grinding product is screened and classified 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 and calcined at 570 to 670 ° C for 0.5 to 2 hours to obtain light-burned magnesium recovered by suspension calcination; the light-burned magnesium is then purified by air separation to finally prepare a high-purity light-burned magnesium product.

[0005] Chinese invention patent 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 ore powder; 3) pulping of magnesite: adding water to the ore powder after grinding in step 2), mixing evenly and preparing slurry to obtain ore pulp; 4) flotation of magnesite: sending the slurry after pulping in step 3) to 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 it.

[0006] The existing belt conveyor diverts and transports the screened materials. Due to the structural limitations of the belt conveyor, in order to obtain sufficient conveying height, the belt conveyor needs to be 25 meters long, which occupies a large area. Utility Model Content

[0007] The purpose of the utility model is to provide a low-grade magnesite ore washing and grading system, overcome the shortcomings of the existing technology, adopt a variable inclination belt conveyor to divert and convey the screened material, 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 angle, resulting in ore accumulation and collapse and causing safety accidents.

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

[0009] The low-grade magnesite ore washing and grading system includes a vibrating screen, a grading conveyor 1, a grading conveyor 2, a sorting conveyor and a cleaning and impurity removal bin. The inlet of the vibrating screen is provided with a feed bin, the outlet of the screen material is located on the feeding side of the grading conveyor 1, the outlet of the screen material is located on 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 on the feeding side of the sorting conveyor; the water supply and drainage of the cleaning and impurity removal bin are connected to the circulating water system through pipelines respectively, and the grading conveyor 1 and / or the grading conveyor 2 are connected to the circulating water system respectively, and the grading conveyor 1 and / or the grading conveyor 2 are connected to the circulating water system. 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. Left rollers and right rollers 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 articulated 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 degrees; 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 degrees.

[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 a bolt, and the other end of the arc-shaped positioning plate is hinged to the column by a bolt; 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 1 is provided at one end of the roller body, and sprocket 2 is provided at the shaft end of the reducer. Sprocket 1 and sprocket 2 are engaged 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 provided on the return roller bracket, the centerline 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.

[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 suspension component. 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, and the chute and the vibrating feeder are respectively connected to the shelf of the cleaning and impurity removal bin through suspension components. When ore falls on the chute, the chute is inclined at an angle of 8-15° toward the outlet side.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[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, effectively reducing the floor space of the production line and reducing investment costs.

[0021] 2) The variable inclination belt conveyor adopts a multi-section articulated structure base frame, which makes the angle adjustment of the belt conveyor more flexible, avoiding excessive local inclination angles, which may cause ore accumulation and collapse and lead to safety accidents;

[0022] 3) The ore is graded before cleaning, and the 12-30mm particle size ore 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 This is a schematic top view of the structure of an embodiment of the utility model;

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

[0025] Figure 3 yes Figure 1 Cross-sectional view along line BB;

[0026] Figure 4 This is a schematic diagram of the variable inclination frame structure of the variable angle section II in the embodiment of the present utility model;

[0027] Figure 5 yes Figure 4 Cross-sectional view along CC line;

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

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

[0030] Figure 8 This is a schematic diagram of the structure of the cleaning and impurity removal bin in an embodiment of the utility model;

[0031] Figure 9 It is a schematic diagram of the structure of the linear vibrating screen in the embodiment of the present utility model.

[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- hinged bolt, 13- suspended vibrating chute, 14- slide trough, 15- vibrating feeder, 16- hanging part, 17- roller body, 18- reducer, 19- sprocket 1, 20- sprocket 2, 21- chain, 22- longitudinal beam, 23- variable inclination frame, 24- sump, 25- column, 26- return roller bracket, 27- arc-shaped positioning plate, 28- hinged ear plate. DETAILED DESCRIPTION

[0033] The technical solutions of the present invention will be described clearly and completely 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 utility model or the technical solutions in the prior art, the specific embodiments required for use 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 utility model. 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 claimed invention, but rather represents only selected embodiments of the present invention.

[0036] See Figure 1-3 , is a schematic diagram of an embodiment of the low-grade magnesite ore washing and grading system of the utility model, comprising a linear vibrating screen 1, a grading conveyor 2, a grading conveyor 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 the material above the screen is located on the feeding side of the grading conveyor 2, a outlet for the material below the screen is located on the feeding side of the grading conveyor 2 3, a discharge side of the grading conveyor 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 water supply and discharge of the cleaning and impurity removal bin 5 are connected to the circulating water system through pipelines respectively.

[0037] Grading Conveyor 1-2 has a discharge elevation of 4.5 meters, with a maximum elevation angle of 15°47'. Grading Conveyor 2-3 has a discharge elevation of 4.8 meters, with a maximum elevation angle of 18°36'. Grading Conveyor 1-2 is a B650 belt conveyor with a belt speed of 1.25 m / s. Grading Conveyor 2-3 is a B650 belt conveyor with a belt speed of 1.20 m / s and a maximum elevation angle of 15°. Sorting Conveyor 4 is a B800 belt conveyor with a belt speed of 0.20 m / s. It is a parallel belt manual sorting conveyor that can also be used in conjunction with various artificial intelligence sorting machines.

[0038] See Figure 4-5Grading Conveyor 1 2 and Grading Conveyor 2 3 are each mounted on a variable-angle frame 23, which is a steel frame or concrete platform. Grading Conveyor 1 2 and Grading Conveyor 2 3 consist of a horizontal section I, a variable-angle section II, and a straight section III along their length. Horizontal section I is located on the feed side, while straight section III terminates at the discharge side. A base frame 7 is located at the bottom, and an intermediate roller 8 is centrally located at the top of the base frame. Flanking intermediate roller 8 are left and right rollers 9 and 10, respectively. A return roller 11 is located below 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 longitudinal beam 22 is provided with hinged lugs 28 at both ends. 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. Two return rollers are symmetrically mounted on the return roller bracket 26. The centerline angle between the two return rollers is 120-150 degrees. Multiple rubber rings are provided on the surface of the return roller 11 in parallel.

[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 2 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 Schematic diagram of the connection of multiple pedestals in variable angle section II. The arc radius of the variable angle frame in variable angle section II is 30 meters. The pedestals in variable angle section II are multi-section hinged structures, with adjacent pedestals connected by hinge bolts 12. This ensures that the conveying angle of any section in the variable angle section does not exceed the ore's angle of repose.

[0042] See Figure 8 A suspended vibrating chute 13 is installed at the bottom outlet of the cleaning and impurity removal bin 5, with a water collection trough 24 located below. 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 is located above the loading 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 each connected to the rack of the cleaning and impurity removal bin 5 via the suspension 16. The suspension 16 is an elastic suspension with a compression spring inside. When ore falls onto the chute 14, the chute 14 tilts at an angle of 8-15° toward the outlet to facilitate ore discharge. The vibrating feeder 15 is a GZ6 motor vibrating feeder.

[0043] See Figure 9 The linear vibrating screen 1 has an 8° screen installation angle and is suspended. Two vibration motors are installed on the bracket above the screen. The screen hole diameter is 12mm×12mm. The particle size of the oversize material is 12-30mm, and the particle size of the undersize material is less than 12mm.

[0044] When the utility model 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 of more than 12 mm and an undersize part of less than 12 mm. The oversize material is put on the grading conveyor 2, and the undersize material is put on the grading conveyor 2 3. The grading conveyor 1 2 and the grading conveyor 2 3 are both along the variable inclination frame 23, and their discharge ports reach an elevation of more than 4 meters 5. The end point of the grading conveyor 2 3 is the fine material yard, and the end point of the grading conveyor 1 2 is the 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, white or off-white. Iron-containing magnesite is yellow to brown, has a vitreous luster, and exhibits complete rhombohedral cleavage. Porcelain magnesite exhibits a conchoidal fracture. After thorough cleaning, magnesite is easily separated by manual or artificial intelligence sorting machines, allowing for the purification of low-grade (poor) magnesite and facilitating its further application.

[0046] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and 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. A feed bin is provided at the inlet of the vibrating screen, an outlet for the material above the screen is located on the feeding side of the grading conveyor 1, an outlet for the material below the screen is located on 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 on the feeding side of the sorting conveyor; the water supply and drainage of the cleaning and impurity removal bin are connected to the circulating water system through pipelines, respectively, and is characterized in that: The grading conveyor 1 and / or the grading conveyor 2 are respectively arranged on a variable inclination frame. 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. 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 articulated 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, 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 degrees; 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 degrees.

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

5. The low-grade magnesite ore washing and grading system according to claim 1, 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, characterized in that: The base frame includes a longitudinal beam, a column and a return roller bracket, and 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, and 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 a bolt, and the other end of the arc-shaped positioning plate is hinged to the column by a bolt; the return roller bracket is provided with a return roller.

7. The low-grade magnesite ore washing and grading system according to claim 1, characterized in that: The power roller includes a roller body, a reducer, a sprocket and a chain. Sprocket 1 is provided at one end of the roller body, and sprocket 2 is provided at the shaft end of the reducer. Sprocket 1 and sprocket 2 are engaged 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 rollers.

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 suspension member. 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 suspension members. When ore falls on the chute, the chute is inclined at an angle of 8-15° toward the outlet side.

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