CN106944224B - A high-voltage electric pulse crushing device for ore pretreatment - Google Patents

Abstract

The invention discloses one kind to be used for the pretreated high electric field pulse ore crushing apparatus of ore, and the ore belonged in mineral processing crushes preconditioning technique field.Its device mainly includes power supply, single-phase voltage regulator, exchange ignition transformer, six voltage doubling rectifing circuits, super-pressure ceramic capacitor, gas switch, high-field electrode, conductive cylinder, electric discharge muck bucket, vibration screen, dielectric, solid-liquid separator and product collector etc., and the above each unit is connected into a complete device systems by conducting wire and other auxiliary devices fixed installation.Ore alternative dissociation after the present apparatus is handled is broken, and running crack and crack is generated on ore internal mineral interface, and then improve mineral cleavage characteristic, reduces subsequent processing energy consumption, while avoiding the overground of valuable mineral, improves separation index.

Description

A high-voltage electric pulse crushing device for ore pretreatment

technical field

The invention belongs to the technical field of ore crushing and preprocessing of mineral processing engineering, and particularly relates to a high-voltage electric pulse crushing device for ore preprocessing.

Background technique

Most of the mineral resources in my country are lean ore, with many symbiotic and associated components in the ore deposit. The ore composition is relatively complex and the embedded particle size is fine. Therefore, the beneficiation of ore in my country faces many problems such as greater difficulty, low efficiency and high cost. Among them, the most important problems in the field of ore crushing are: high investment and maintenance costs for crushing and grinding equipment, high energy consumption, excessive production of unprocessable fine-grained grades and insufficiently dissociated coarse-grained grades, increasing subsequent sorting operations difficulty.

The crushing method currently used in the industry is mainly mechanical crushing. Mechanical crushing is to dissociate useful minerals and gangue minerals by reducing the particle size of the ore. For the ore with close combination of useful minerals and gangue minerals, mechanical crushing is prone to overgrinding of useful minerals during the crushing process. The recovery ability of useful minerals decreases with the reduction of particle size, so that some useful minerals are lost and cannot be recovered effectively.

The useful minerals in the ore and the gangue minerals (such as iron minerals and quartz minerals in the iron ore) have obvious differences in electrical conductivity. Development is important. On the basis of ensuring the quality of useful minerals, the operation cost of the enterprise is saved and the waste of resources is reduced.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the existing mechanical crushing technology, the present invention provides a high-voltage electric pulse discharge ore crushing device with the function of selectively crushing ore. The device is based on the difference in electrical conductivity between useful metallic minerals and gangue non-metallic minerals in the ore, and the useful mineral grains are fully dissociated through selective crushing, that is, the useful minerals are broken into individual mineral particles according to the grains, ensuring that the single mineral in the crushed product is broken. The particle size and quality of the dissociated useful minerals can meet the requirements of the subsequent sorting process and reduce the energy consumption of the subsequent processing.

A high-voltage electric pulse crushing device for ore pretreatment provided by the present invention is shown in FIG. Voltage doubling rectifier circuit (4), ultra-high voltage ceramic capacitor (5), copper rod (6), high voltage electrode (7), conductive cylinder (8), discharge crushing barrel (9), vibrating screen (10), Insulating liquid (11), ore feeding bin (12), insulating liquid bin (13), grounding wire (14), solid-liquid separator (15), product collector (16), gas switch (17), high-voltage wire ( 18), an insulating barrel cover (19), an insulating liquid circulation pipeline (20), a vibration device (21), and an insulating vibration rod (24). The single-phase voltage regulator (2) is connected to the AC ignition transformer (3), and the output end of the AC ignition transformer (3) is connected to a six-fold voltage rectifier circuit (4), which is a six-fold voltage rectifier circuit. (4) The output end is connected with the input end of the ultra-high voltage ceramic capacitor (5), and the two ends of the ultra-high voltage ceramic capacitor (5) are connected in parallel with the two ends of the gas switch (17), so as to form a device capable of outputting high-voltage electricity. A pulsed high-voltage rectifier oscillator circuit, the output end of the high-voltage rectifier oscillator circuit, that is, the output end of the parallel ultra-high voltage ceramic capacitor (5) is connected with the high-voltage wire (18), and one end of the plurality of copper rods (6) is connected in parallel with the high-voltage wire ( 18), a high voltage electrode (7) is installed on the other end of the copper rod (6), the copper rod (6) is insulated and fixed on the insulating barrel cover (19) located on the top of the discharge crushing barrel (9), and the The end installed with the high-voltage electrode (7) penetrates deep into the discharge crushing barrel (9); the outer layer of the discharge crushing barrel (9) is made of insulating material, among which nylon material is preferred, and the discharge crushing barrel (9) A conductive cylinder (8) is embedded in the inner lining of the discharge crushing barrel (9), the upper part of the discharge crushing barrel (9) is cylindrical, and the bottom is an inverted cone. The net (10), a vibration device (21) is fixed on the side wall of the upper insulating part of the discharge crushing barrel (9), and is connected with the vibrating screen (10) through an insulating vibration rod (24); the discharge crushing barrel (9) ) is connected with the solid-liquid separator (15) through the discharge port and the conveying pipeline. The upper side wall of the ore barrel (9) is respectively provided with an insulating liquid inlet and an ore inlet, wherein the insulating liquid inlet is connected with the insulating liquid silo (13) through a pipeline, and the ore inlet is connected to the ore silo (12) through a chute or a feeding belt. One end of the ground wire (14) passes through the outer layer of the discharge crushing barrel (9) and is connected to the inner conductive cylinder (8), and the other end of the ground wire (14) is directly grounded to form a loop of the entire circuit.

When working, the power supply (1) is started to supply power, and the voltage is transformed by the single-phase voltage regulator (2), the AC ignition transformer (3) is boosted, and the six-fold voltage rectifier circuit (4) is rectified and boosted to output high-voltage direct current to supply the ultra-high voltage The ceramic capacitor (5) is charged, and the rise time of the charging voltage is in the order of microseconds. When the voltage across the ultra-high voltage ceramic capacitor reaches a certain value, the gas switch (17) connected in parallel with it is broken down and turned on, and the output rise time is The high-voltage electrical pulse of nanosecond magnitude is loaded onto the copper rod (6) through the high-voltage wire (18) and conducted to the high-voltage electrode (7); the high-voltage electrode (7) and the conductive cylinder (8) are made of stainless steel and insulated The barrel material is nylon. The conductive cylinder (8) is a ground electrode and is connected to the ground through a ground wire (14); a vibrating screen (10) is installed on the cylindrical bottom of the discharge crushing barrel (9), and the vibrating screen passes through an insulating vibrating rod (24). ) is connected with the vibrating device (21) fixed on the side wall of the insulating part of the upper part of the discharge crushing barrel (9), and the size of the screen hole can be adjusted according to the requirements; The high-voltage electric pulse formed by the pulse discharge device is output to the large-particle ore (22) placed in the conductive cylinder (8) through the high-voltage electrode (7), and is connected to the conductive cylinder (8) with a ground wire (14) to form loop. A voltage difference is formed between the high-voltage electrode (7) and the conductive cylinder (8); when the voltage on the high-voltage electrode (7) reaches a certain value, a discharge occurs between the high-voltage electrode (7) and the cylinder (8) , the discharge occurs inside the ore immersed in the insulating liquid (11). Since the insulating strength of water as the insulating liquid is greater than that of the ore under the action of nanosecond pulses, the useful minerals and veins are formed along the inside of the large-grained ore (22). Plasma channels are repeatedly formed between the stone-mineral interfaces, and after multiple discharges between the high-voltage electrode and the conductive cylinder, the large ore (22) with a particle size of 10mm-100mm can be broken into small particles with a particle size of 5mm-60mm The ore (23) and the small particle ore (23) are screened by the vibrating screen (10) and then fall into the lower part of the cone at the bottom of the insulating ore crushing barrel (9). Out of the barrel (9) and into the solid-liquid separator (15), the small particle ore (23) separated by the solid-liquid separator (15) enters the product collector (16) for subsequent crushing and grinding operations. Continuous use. The final particle size depends on the mesh size, which can be adjusted on request.

The high-voltage electric pulse ore crushing device completed by the present invention should be used as follows.

(1) Start the vibrating device (21), and drive the vibrating screen (10) to vibrate through the insulating vibrating rod (24); its vibration frequency is 300 times/min～1200 times/min, close the bottom of the discharge crushing barrel (9) The valve of the discharge port is opened, and the valves of the insulating liquid inlet and the ore inlet are respectively opened, and a certain amount of insulating liquid (11) and large particle ore (22) are introduced into the discharge crushing barrel (9), wherein the insulating liquid (11) The volume ratio to the large particle ore (22) should be 1:2 to 5; when the insulator (11) and the large particle ore (22) are filled to 2/3 to 3/4 of the total volume of the discharge crushing barrel (9) Close the valves of the above two inlets;

(2) The starting power supply (1) supplies power, which is transformed by the single-phase voltage regulator (2), the AC ignition transformer (3) is boosted and the six-fold voltage rectifier circuit (4) is rectified and boosted to output high-voltage direct current to supply the ultra-high voltage The ceramic capacitor (5) is charged, and then continuously transmits electric pulses to the high-voltage electrode (7) through the subsequent circuit, and transmits it to the large-grained ore (22), so that it is cracked and broken. The pulse intensity is 50kV ~ 300kV, and the pulse frequency is 10Hz ~ 20Hz;

(3) Start the power supply (1) 10-15 minutes after the power supply, open the insulating liquid inlet and ore inlet valves of the discharge crushing ore barrel (9) again, and open the outlet valve at the same time to control the insulator (11) and the large particle ore. (22), to ensure that the volume ratio of the insulating liquid (11) and the large-grained ore (22) in the discharge crushing barrel (9) is maintained at 1:2 to 5, and the insulating liquid (11) and the large-grained ore (22) ) is filled with 2/3 to 3/4 of the total volume of the discharge crushing barrel (9);

(4) Open the discharge port valve of the discharge crushing barrel (9) and simultaneously start the solid-liquid separator (15) connected with it, and the small particle ore (23) separated by the solid-liquid separator (15) enters the product In the collector (16) for subsequent use, the separated insulating liquid (11) is returned to the insulating liquid silo (13) through the insulating liquid circulation pipeline (20) for recycling.

Compared with the prior art, the characteristics and beneficial effects of the present invention are:

Compared with the traditional sample crushing device, this highly selective crushing has many advantages: easy cleaning, no cross-contamination; selective crushing, without destroying the crystal form of minerals, etc. Electric pulse crushing is the most ideal intergranular fracture method, which can not only crush the ore, but also generate extended cracks and cracks on the mineral interface inside the ore, thereby improving the cleavage characteristics of the mineral. After the ore is crushed by high-voltage electric pulses, on the one hand, the strength of the ore can be greatly reduced, and it is expected to reduce the energy consumption of grinding by more than 30%; The degree of separation helps to improve the ore sorting index. The main innovations of the present invention are:

(1) The structure design of multiple electrode pairs realizes the high efficiency and continuity of the high-voltage electric pulse discharge ore crushing device for ore crushing.

(2) The size of the screen can be changed according to the requirements of the particle size of the crushed ore to meet the needs of crushing and grinding operations.

(3) The high-voltage electric pulse discharge crushing equipment can dissociate the ore along the mineral grain interface, that is, selectively crush it, instead of crushing it, so that the useful minerals can be removed from the surrounding while maintaining the original form of the components. separated from other components.

(4) The high-voltage electric pulse discharge crushing equipment can generate more single mineral particles without reducing the particle size of the useful mineral particles in the ore. Compared with mechanical crushing, it can increase the useful mineral content of the crushed products and improve the crushing products. The monomer dissociation degree is beneficial to the reduction of energy consumption in the subsequent treatment process and saves the cost of the enterprise.

Description of drawings

Figure 1 is a schematic structural diagram of a high-voltage electric pulse crushing device for ore crushing pretreatment, in the figure: 1 is a power supply, 2 is a single-phase voltage regulator, 3 is an AC ignition transformer, and 4 is a six-fold voltage rectifier circuit , 5 is an ultra-high voltage ceramic capacitor, 6 is a copper rod, 7 is a high-voltage electrode, 8 is a conductive cylinder, 9 is a discharge crushing barrel, 10 is a vibrating screen, 11 is an insulating liquid, 12 is a feeding bin, and 13 is a Insulating liquid tank, 14 is the ground wire, 15 is the solid-liquid separator, 16 is the product collector, 17 is the gas switch, 18 is the high-voltage wire, 19 is the insulating barrel cover, 20 is the insulating liquid circulation pipeline, 21 is the vibration device, 22 is a large particle ore, 23 is a small particle ore, and 24 is an insulating vibrating rod.

Figure 2 is a scanning electron microscope observation diagram of a standard crushed product of magnetite.

FIG. 3 is a scanning electron microscope observation diagram of a high-voltage electric pulse crushing product of magnetite.

Figure 4 is a scanning electron microscope observation image of a standard crushed product of extremely lean hematite ore.

FIG. 5 is a scanning electron microscope observation diagram of a high-voltage electric pulse crushing product of extremely lean hematite ore.

Detailed ways

The present invention will be further described below in conjunction with the embodiments.

The high-voltage electric pulse discharge crushing equipment used in the embodiment of the present invention uses the same device for crushing the ore as the structure described in the content of the invention. The device is used for ore crushing, and the yield of each particle size, metal content, metal content, and metal content of the crushed products are analyzed. Monomer dissociation degree, microscopic morphology, and compared with mechanical crushing products.

Example 1

The ore sample used in this example is Dagushan magnetite, and its main chemical composition is shown in Table 1. It can be seen from Table 1 that the valuable element in the raw ore is iron, the TFe grade is 32.61%, and the FeO content is 17.49%; the main impurity is SiO ₂ , accounting for 45.77%; the content of harmful impurities S and P is low. The chemical phase analysis of the Fe element in the raw ore is shown in Table 2. It can be seen from Table 2 that the iron in the ore mainly exists in the form of magnetite, and the iron occupancy rate in the magnetite reaches 79.70%, followed by siderite, red (limonite) iron ore It exists in the form of iron silicate and iron sulfide, and a small amount exists in the form of iron sulfide.

Table 1 Analysis of chemical composition of raw ore/%

Table 2 Chemical phase analysis results of iron in ore/%

The Dagushan magnetite is crushed with a high-voltage electric pulse discharge crushing device. The 500Kg ore with a content of +30mm accounting for 70% is fed into a high-voltage electric pulse equipment cylinder, the electrode spacing is 100mm, the discharge voltage is 60kV, the ore is continuously discharged and crushed 400 times, the power supply is disconnected, and the crushed products under the sieve are collected after the discharge is completed. The same weight of ore was crushed with a double-roll crusher to obtain a standard crushed product, and the characteristics of the two crushed products were compared.

The two crushed products were subjected to particle size sieve analysis and the iron content of each particle grade was measured. The results are shown in Table 3 and Table 4.

Table 3 Particle size distribution of standard crushed product and TFe grade of each particle grade product

Table 4 The particle size distribution of high-voltage electric pulse crushing products and the TFe grade of each particle grade product

It can be seen from Table 3 and Table 4 that the content of fine particle fraction of high-voltage electric pulse crushed products is higher than that of standard crushed products, the content of -1mm is increased from 20.35% to 29.19%, and the TFe grade is increased from 34.92% to 35.72%. This shows that the high-voltage electric pulse crushing equipment can crush ores more efficiently, and at the same time increase the content of useful minerals.

In this study, scanning electron microscopy was used to observe the microscopic morphology of the reduction products of magnetite, and the results are shown in Figure 2 and Figure 3 in the accompanying drawings.

It can be seen from Figure 2 that the magnetite crushed product of the pair of rollers has cracks in the useful mineral magnetite, that is, transgranular crushing; it can be seen from Figure 3 that the high-voltage electric pulse crushing of magnetite dissociates along the mineral grain interface, Preserves the original form of useful minerals.

Example 2

The ore sample used in this example was taken from the extremely lean hematite ore in the ore dressing plant of Anqian Mining Co., Ltd., and its main chemical composition is shown in Table 5. It can be seen from Table 5 that the main metal element in the extremely lean hematite ore is iron, and the TFe grade is 19.34%, which belongs to the extremely lean hematite ore. Among them, the FeO grade is 0.68%, and it can be seen that the content of magnetite in the ore is less. The highest content of SiO ₂ is 75.18%, indicating that the main gangue mineral is silica. Secondly, the contents of Al ₂ O ₃ and MgO are 0.17% and 0.28%, respectively, and the contents of other elements are lower.

Table 5 Analysis of chemical composition of raw ore/%

The extremely lean hematite ore is crushed in the laboratory with a high-voltage electric pulse discharge crushing device. Feed 500Kg of ore with a particle size of +20mm and a content of 85% into a cylinder equipped with high-voltage electric pulses. The electrode spacing is 100mm and the discharge voltage is 80kV. Continuously discharge and crush the ore for 600 times, disconnect the power supply, and collect the crushed products under the sieve after the discharge is complete. . The same weight of ore was crushed with a double-roll crusher to obtain a standard crushed product, and the characteristics of the two crushed products were compared.

The particle size sieve analysis test of the two crushed products and the determination results of the iron content of each particle grade are shown in Table 6 and Table 7.

Table 6 Particle size distribution of standard crushed product and TFe grade of each particle grade product

Table 7 Particle size distribution of high-voltage electric pulse crushing products and TFe grade of each particle grade product

It can be seen from Table 6 and Table 7 that the content of fine particle fraction of high-voltage electric pulse crushed products is higher than that of standard crushed products, the content of -0.1mm is increased from 21.96% to 24.73%, and the TFe grade is increased from 22.50% to 23.33%. This shows that the high-voltage electric pulse crushing equipment can crush ores more efficiently, and at the same time increase the content of useful minerals.

In this study, scanning electron microscopy was used to observe the microscopic morphology of the reduction products of extremely lean hematite ore, and the results are shown in Figures 4 and 5.

It can be seen from Figure 4 that cracks appear randomly in the double-roll crushed product of extremely lean hematite ore, and the crushing is achieved by mechanical force, and some cracks in the ore do not follow the hematite-quartz interface. From Figure 5, it can be seen that the fracture cracks of the ore particles are rougher and accompanied by burning marks and pores after the extremely lean hematite ore is crushed by the high-voltage electric pulse, which indicates that the hematite-quartz interface is broken during the high-voltage electric pulse crushing process. There is a high temperature environment in the discharge channel formed at the site, which aggravates the fragmentation of the ore particles; and the fragmentation is dissociated along the mineral grain interface to maintain the original form of the useful components.

Claims (1)

1. one kind is used for the pretreated high electric field pulse ore crushing apparatus of ore, the daily power supply unit of the device is power supply (1), Characterized by further comprising single-phase voltage regulator (2), exchange ignition transformer (3), six voltage doubling rectifing circuits (4), super-pressure ceramics Capacitor (5), copper rod (6), high-field electrode (7), conductive cylinder (8), electric discharge muck bucket (9), vibration screen (10), dielectric (11), ore storage bin (12), dielectric storehouse (13), earth lead (14), solid-liquid separator (15), product collector (16), gas are given Switch (17), high-voltage conducting wires (18), insulation bung (19), dielectric circulating line (20), vibration device (21), insulation vibrating arm (24), wherein power supply (1) is connected with single-phase voltage regulator (2), single-phase voltage regulator (2) again with exchange ignition transformer (3) be connected It connects, exchange ignition transformer (3) output termination six voltage doubling rectifing circuits (4), six voltage doubling rectifing circuits (4) output end and super-pressure The input terminal of ceramic capacitor (5) is connected, and the both ends of the both ends of super-pressure ceramic capacitor (5) and gas switch (17) are mutually simultaneously Connection, the high-voltage rectifying oscillating circuit that can export high electric field pulse is constituted with this, the output end of high-voltage rectifying oscillating circuit is Super-pressure ceramic capacitor (5) output end after parallel connection is connected with high-voltage conducting wires (18), and one end of multiple copper rods (6) is connected in parallel on On high-voltage conducting wires (18), the other end of copper rod (6) is equipped with high-field electrode (7), and copper rod (6) insulating mounting, which is fixed on, is located at electric discharge On insulation bung (19) at the top of muck bucket (9), and the one end for being equipped with high-field electrode (7) is deep into electric discharge muck bucket (9) in；The outer layer of electric discharge muck bucket (9) is made of insulating material, and the liner of electric discharge muck bucket (9) is inlaid with conductive cylinder (8), The top of electric discharge muck bucket (9) is tubular, and it is the installation of tubular bottom in place of the transition of tubular and back taper that bottom, which is back taper, Have vibration screen (10), is fixed with vibration device (21) in the upper portion insulating partial sidewall of electric discharge muck bucket (9), and and vibrating screen Net (10) passes through insulation vibrating arm (24) connection；Discharge muck bucket (9) back taper bottom by discharge port and conveyance conduit with Solid-liquid separator (15) is connected, and solid-liquid separator (15) is followed by product collector (16) and dielectric circulating line (20), puts Dielectric entrance and ore inlet are had in the upper portion side wall of electric muck bucket (9), wherein dielectric entrance is same by pipeline Dielectric storehouse (13) is connected, and ore inlet gives ore storage bin (12) to be connected by the way that chute or feeding belt are same；Earth lead (14) One end pass through electric discharge muck bucket (9) outer layer with its inside conductive cylinder (8) be connected, the other end of earth lead (14) It is directly grounded,

Wherein, the vibration frequency of vibration device (21) is 300 times/min to 1200/min.