WO2013038367A2 - Système pour la mesure dynamique de la dureté d'une roche permettant d'obtenir le paramètre kwh/ton (puissance/flux massique), équivalent au paramètre obtenu dans le procédé industriel de broyage ou concassage d'un minéral - Google Patents

Système pour la mesure dynamique de la dureté d'une roche permettant d'obtenir le paramètre kwh/ton (puissance/flux massique), équivalent au paramètre obtenu dans le procédé industriel de broyage ou concassage d'un minéral Download PDF

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Publication number
WO2013038367A2
WO2013038367A2 PCT/IB2012/054784 IB2012054784W WO2013038367A2 WO 2013038367 A2 WO2013038367 A2 WO 2013038367A2 IB 2012054784 W IB2012054784 W IB 2012054784W WO 2013038367 A2 WO2013038367 A2 WO 2013038367A2
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WIPO (PCT)
Prior art keywords
rock
dynamic measurement
rock hardness
self
computer
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PCT/IB2012/054784
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English (en)
Spanish (es)
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WO2013038367A3 (fr
Inventor
Iván Luino SOLÍS BLAU
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Sgs Lakefiled Research Chile S.A.
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Application filed by Sgs Lakefiled Research Chile S.A. filed Critical Sgs Lakefiled Research Chile S.A.
Publication of WO2013038367A2 publication Critical patent/WO2013038367A2/fr
Publication of WO2013038367A3 publication Critical patent/WO2013038367A3/fr

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/56—Investigating resistance to wear or abrasion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C13/00—Disintegrating by mills having rotary beater elements ; Hammer mills
    • B02C13/02—Disintegrating by mills having rotary beater elements ; Hammer mills with horizontal rotor shaft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C25/00—Control arrangements specially adapted for crushing or disintegrating
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
    • G01N2001/2866—Grinding or homogeneising

Definitions

  • the present invention relates to the mining industry and to rock metallurgical tests.
  • the present invention relates to a system and method of dynamic measurement of rock hardness, measured through the energy required for grinding or crushing, in kWh / ton (power / mass flow), equivalent to that obtained in the industrial process of grinding or crushing.
  • crushers are used, such as, for example, semi-autogenous SAG (Semi Autogeneous Grinding) mills, Ball Mills; crushers: swivel, jaw, impactor, cone, roller, hammer and vertical shaft impactors, among others.
  • SAG Semi Autogeneous Grinding
  • Ball Mills Crushers: swivel, jaw, impactor, cone, roller, hammer and vertical shaft impactors, among others.
  • the first is the SAG mill that produces the fracture of the rocks by the potential energy of the rock itself when it falls.
  • the second case is that of the ball mill, which is smaller in diameter than the SAG mill, there is a fracture of the rock by the potential energy of the steel balls when it hits the rocks.
  • the third case corresponds to the jaw or cone crusher that causes compression fracture of the rock between two metal walls.
  • Mill grinding SAG Reduction of rock size twelve times.
  • the jaw crusher like the ball mill, consumes high energy in a vacuum, since it has high-weight eccentric flywheels, which allow the continuity of fracture of the rocks and therefore high consumption of empty energy it does not admit to clearly discriminate different rock hardnesses because the energy with mineral load is very similar to the consumption of empty energy.
  • Static or indirect tests or tests are those where the measurement process is discrete of a sample and its result is empirical, while dynamic tests or tests refer to the direct and continuous measurement of the kWh / ton parameter (power / flow mass) in real time and are dimensionally equal to those that occur in an industrial plant, and therefore dynamic rock tests are more accurate and less error than static ones.
  • Empirical results are understood as the results obtained through the use of real data. These empirical results data are used to correlate laboratory tests and thereby obtain an approximation of reality.
  • the SPI test consists of a static test with a mill of approximate dimensions of 30 cm in diameter by 12 cm wide, with a load of steel balls inside and It has a rotation speed of approximately 50 rpm. In this mill 100% of a fixed sample of 2 kg of material is entered, with a grain size of less than 19.05 mm. This test is controlled periodically (every 10 minutes) and manually, how much of the load has reached the final size of 10 meshes (1, 7 mm) for which the load must be stopped and emptied for measurement. After successive downloads and reloads made by the operator, the test ends when 80% of the total has reached the control size of 1, 7 mm.
  • the final result is the time it takes to obtain the final control size (1, 7 mm), which must be correlated with an industrial database to know the value of the kWh / ton parameter, which is the one measured in The industrial plant.
  • Another difficulty of this test is the incorporation of energy meters to the motors, since they have a high energy consumption running in a vacuum due to their load of steel balls and therefore, it is difficult to discriminate, what part of the total Energy consumed corresponds only to the fracture of the rocks.
  • the JK test (Drop Weight Test, is a static test developed to be able to size a SAG mill in the construction phase of an industrial plant and make forecasts of production of plants in operation.
  • This JK test is cumbersome since it uses 300 rock particles in five different sizes (53, 37, 26, 19 and 13 mm) and the potential energy is used at three different levels by dropping a weight on the particle and measuring the degree of fracture suffered by the particle after impact. Each of the three energy levels is used for each of the five particle sizes and this series is repeated 20 times, that is, in total 300 particles are struck, one by one. A plot of potential energy (Joule) is then plotted versus amount of fractured material in a control size. The JK test measures the energy needed to fracture a rock from its initial size to a final size. The initial particle sizes are those defined above. The final size is not unique and is defined as 10% of the initial particle size (t 10 ).
  • t 10 is finally the weight of the pass-through size in the measure t i o-
  • the SPI and JK tests have the disadvantages of being static, using industry empirical databases to correlate and obtain the kWh / ton parameter, and measuring manually, which would generate a possible measurement error given the operator intervention, where they also have a measurement time greater than the time and difficulty in having statistical validity, given the complexity of obtaining more than 1,000 data in the tests.
  • Patent US6,752,338 describes a pilot SAG plant on an experimental scale with an external chamber diameter of between 0.6 and 1.5 meters, and a method to use it to test the properties of the mineral entered, this mill requires a sample of 2 kilograms of the mineral that works as a laboratory test per batch, but not continuously.
  • Patent application US20090199625 refers to an apparatus and method for determining the breaking properties of a particulate material, which comprises; a support, a rotor with a guide channel, a propeller, a particle feed channel, a stator with impact surface, a collector of pieces of particulate material, and a system for controlling and adjusting the impact speed of the particulate material.
  • the breakage result of the material entered is analyzed and the result is correlated with the material breakage properties.
  • Patent US6,752,338 and patent application US20090199625 do not dynamically measure, none simulate the fracture of the rock generated in SAG mill, ball or crusher and have the disadvantage of using industry empirical databases to obtain the kWh / ton parameter.
  • a dynamic rock hardness measurement system that obtains the kWh / ton parameter (power / mass flow), equivalent to that obtained in the industrial grinding or crushing process without requiring bases of empirical data of the industry, in an automated way, with statistical validity and with error less than 5%.
  • This system comprises an impact mill (20), which simulates the fracture of the rock in a mill or crusher, a self-calibrating scale (30) with two-way communication, a power supply (40), an electric servo motor (50) and a computer (60).
  • the present invention provides a dynamic rock hardness measurement system delivering the kWh / ton parameters equivalent to that obtained in the industrial milling or crushing process, without requiring empirical databases of the industry or the intervention of an operator, thus avoiding measurement errors and also has statistical validity, with an error of less than 5% in the measurement.
  • this system has the advantage that it fractures the rock avoiding shear, due to the cylindrical shape of interchangeable wear plates (21) and the cylindrical shape of interchangeable impactor plates (23), and thereby simulates one of the types of fractures that occur inside the mill or crusher, such as the impact with a steel ball (convex surface) on the rock, since compression is performed at a point of contact.
  • Figure ⁇ illustrates a scheme of the system of the present invention.
  • Figure 2 illustrates a schematic of a grinding chamber of a configuration of the present invention.
  • Figure 3 illustrates a side scheme of a grinding chamber of a configuration of the present invention.
  • Figure N ° 4 shows a graph of specific energy consumption (Soft Mineral Quarzite) in kWh / ton.
  • Figure 5 shows a graph of total torque as a percentage of the nominal electric servo motor (50) of 15.8 Nm.
  • Figure N ° 6 shows a graph of mass flow of 500gr. of feeding.
  • the invention discloses a system and method of fracturing laboratory scale rocks to simulate the specific energy consumption in kWh / ton of the rocks in a mill or crusher.
  • This system uses the impact and abrasion mechanisms for rock fractures using wear-resistant materials without requiring the adjustment or exchange of parts for a minimum duration of 1000 tests.
  • the fracture process is performed at a continuous feeding rate of 100 grams per minute and uses a sample of 500 grams of rock in a size 100% smaller than 12 mm, which fractures to a size of 100% less than 1 mm.
  • the entire process is controlled entirely through a computer and continuously measures the specific energy consumption of the rock in the control sizes.
  • the specific energy consumption determined is exactly equal to the consumption obtained in grinding or crushing for a typical industrial reduction ratio between the sizes of 152.4 mm of feed to 12.7 mm of product.
  • This system of high speed, precision and fully automated allows to measure large quantities of individual samples, achieving greater accuracy in the characterization of the deposit both for the stages of plant design and for the planning of production of plants in operation.
  • This invention consists of a system of dynamic measurement of rock hardness that allows to obtain the parameter of kWh / ton (power / mass flow), equivalent to that obtained in the industrial milling or crushing process, comprising:
  • an impact mill (20) which contains a grinding chamber (24) with a drum shape, where its inner surface contains a series of wear plates interchangeable (21) and a rotating element (22) in the center, which contains at its ends interchangeable impactor plates (23) that rotate fracture the rock against the interchangeable wear plates (21);
  • a self-calibrating scale which allows measuring a continuous mass flow and comprises an automatic calibration system
  • an electric servo motor 50, which allows to measure speed, torque, RPM and position of the rotating element (22); Y
  • a computer that connects with the self-calibrating scale (30), the power supply (40) and the electric motor servo (50).
  • the impact mill (20) contains in its lower part a discharge mesh or sieve (25), which is self-cleaning due to rotating the rotating element (22) the interchangeable impact plates (23) remove the mineral (70) whose Size is larger than that allowed by the perforations (29), not shown in the figures, of the discharge mesh or sieve (25).
  • the discharge mesh or sieve (25), in a preferred configuration, comprises conical perforations (28). These perforations prevent the entrapment of the mineral (70), because they have a smaller diameter through which the material (70) enters through the discharge mesh or sieve (25) and that has a diameter larger than the entrance, where said mill is surrounded by a housing (27).
  • the interchangeable impactor plates (23) and the interchangeable wear plates (21) have a cylindrical shape to prevent them from breaking and making the rock break, without producing rock shear.
  • Said self-calibrating scale (30) is connected to a computer (60) for zeroing each time a test is started and above said self-calibrating scale (30) is located the feeding means (40).
  • the self-calibrating scale (30) allows readings every one second to measure a continuous mass flow of ore (70) with an accuracy of ⁇ 0.1 gr.
  • the self-calibrating scale (30) has a bi-directional capacity which allows data to be read from the computer (60) and sends a signal from the self-calibrating scale (30) to the computer (60) and comprises a standard communication system, where said system Standard communication is preferably an RS-485 serial port.
  • the feeding means (40) in a preferred configuration is a vibrating feeder (41) which vibrates by means of a vibrating mechanism (44) and said feeder, is fed by the mineral (70) through a container or hopper ( 43).
  • the feeding means (40) in another preferred configuration is a belt feeder (42) (not shown in the figures) and said feeder is fed by the mineral (70) through the container or hopper (43).
  • the feeding means (40) in another preferred configuration is a screw feeder (45) (not shown in the figures) and said feeder is fed by the mineral (70) through the container or hopper (43).
  • the feeding medium (40) is commanded by the computer (60) for commissioning, regulating the intensity of vibration, to vary the flow of material (70) to the impacting mill (20);
  • Said electric servo motor (50) is powered by alternating current.
  • the computer (60) uses a computer program for digital data capture, with a sampling rate equal to or greater than 10 milliseconds, for the parameters of the electric motor servo (50) and calculates the weight loss of the self-calibrating balance (30 ).
  • the procedure of dynamic measurement of rock hardness that allows to obtain the kWh / ton parameter (power / mass flow) of the present system is the following: a) Obtain the energy consumption of the electric motor servo (50) in vacuum, to this is done by operating the electric servo motor (50) at a certain number of rpm for a certain time, without loading the ore (70), said variables are set in the computer (60). b) Zero the self-calibrating scale (30).
  • n ⁇ instantaneous motor speed in revolutions per minute
  • T v Torque at no load in percentage of nominal motor torque
  • 0.01 data reading frequency in seconds.
  • the expression of the specific net energy consumption is instantaneously calculated, which is equal to the sum of the instantaneous torque in percentage of the nominal torque of the motor multiplied by instantaneous speed of the empty motor in revolutions per minute, less the empty torque in percentage of nominal motor torque; multiplied by the instantaneous engine speed in revolutions per minute; multiplied by the factor of conversion 4,596x10 "5 to get the result in (kWh / ton) through the software that is Labview.
  • a dynamic measurement of rock hardness was obtained that obtains the kWh / ton parameter occupying the system and method of the present invention, for this a rotary impactor mill (20) was used, without dispersed grinding media, with the ability to process 100 grams per minute of ore (70) through a vibrating feeder (41).
  • the interchangeable impactor plates (23) are made of tungsten carbide, with a hardness of 200 Rockwell C, which rotate due to a power servomotor of 5 kWatt with a torque of 15.8 Newton-meters and a speed of 1,500 (rpm) ), directly coupled and commanded from a computer (60), through the software called Labview.
  • the impactor mill (20) has a drum (26) and a carbon steel casing (27), said impactor mill (20) has interchangeable wear plates (21) in a cylindrical shape of 10 mm diameter tungsten carbide called pantograph , which allows its quick and economical replacement once wear occurs.
  • the discharge mesh (25) which is 10 mm thick stainless steel with 2 mm conical perforations (28) on the side exposed to the mineral (70) and 3 mm output side; where with these conical perforations (28) the entrapment of the ground ore (70) is avoided.
  • the digital sampling rate of the torque signal of the electric motor servo (50) is 10 milliseconds and a self-calibrating scale (30) with a bidirectional RS-485 communication system to the computer (60) was used.
  • the specific fracture consumption of a mineral rock can be measured from a rock of size from 12.7mm. It is only necessary to know what is the proportion, reason for reduction of rock size, in which the rock is fractured in the industrial process and with it the input and output sizes are adjusted to have that same fracture proportion with what is obtained the fracture energy of the rock between those reduction sizes.

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  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Crushing And Grinding (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
  • Disintegrating Or Milling (AREA)

Abstract

L'invention concerne un système et un procédé de fracture de roche à l'échelle d'un laboratoire permettant de simuler la consommation spécifique d'énergie en kWh/ton (puissance/flux massique) des roches dans un broyeur ou un concasseur. Ce système utilise les mécanismes d'impact et d'abrasion pour réaliser la fracture des roches au moyen de matières résistantes à l'usure sans qu'il soit nécessaire d'ajuster ou d'échanger des pièces pour une durée minimum de 1000 essais. Le procédé de fracture est exécuté à un taux d'alimentation continue de 100 grammes par minute et il consiste à utiliser un échantillon de 500 grammes de roche d'une taille 100% inférieure à 12 mm, lequel échantillon est fracturé à une taille 100% inférieure à 1 mm. Le procédé complet est contrôlé intégralement par un ordinateur et il consiste à mesurer en continu la consommation spécifique d'énergie de la roche dans les tailles témoins. La consommation spécifique d'énergie déterminée est exactement égale à la consommation obtenue lors du broyage ou du concassage grâce à la réduction de taille de ces procédés. Ce système extrêmement rapide, précis et totalement automatisé permet de mesurer de grandes quantités d'échantillons distincts, ce qui permet d'obtenir une plus grande précision de la caractérisation du gisement tant au niveau des étapes de conception des usines qu'au niveau de la planification de la production des usines opérationnelles.
PCT/IB2012/054784 2011-09-15 2012-09-13 Système pour la mesure dynamique de la dureté d'une roche permettant d'obtenir le paramètre kwh/ton (puissance/flux massique), équivalent au paramètre obtenu dans le procédé industriel de broyage ou concassage d'un minéral WO2013038367A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CL2011002292A CL2011002292A1 (es) 2011-09-15 2011-09-15 Metodo y sistema para la medicion dinamica de dureza de roca que permite obtener el parametro de kwh/ton equivalente al que se obtiene en el proceso industrial de molienda o chancado de mineral, comprende un molino impactador, una balanza autocalibrable, un medio de alimentacion, un servo electrico y un computador conectado a la balanza y al servo.
CL2292-2011 2011-09-15

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WO2013038367A2 true WO2013038367A2 (fr) 2013-03-21
WO2013038367A3 WO2013038367A3 (fr) 2013-06-27

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WO (1) WO2013038367A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021248233A1 (fr) * 2020-06-11 2021-12-16 Starkey & Associates Inc. Broyeur semi-autogène (sag) continu à l'échelle du laboratoire

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB404608A (en) * 1931-04-08 1934-01-08 Babcock & Wilcox Ltd Process of and apparatus for measuring reduction in size of solids
ES385173A1 (es) * 1969-11-05 1976-04-16 Wedag Wstfalia Dinnendhl Gropp Procedimiento para la regulacion de una instalacion de mol-turacion con gran rendimiento de paso.
US4611763A (en) * 1981-05-27 1986-09-16 Sankyo Dengyo Co. Ltd. Method and apparatus for controlling a grinding mill
US20030038198A1 (en) * 2001-05-31 2003-02-27 Starkey Associates Grinding Design And Process Engineering Ball mill
US20050223798A1 (en) * 2004-04-08 2005-10-13 Starkey John H Testing method for ball mills
US20090199625A1 (en) * 2006-05-18 2009-08-13 The University Of Queensland Apparatus for Determining Breakage Properties of Particulate Material

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB404608A (en) * 1931-04-08 1934-01-08 Babcock & Wilcox Ltd Process of and apparatus for measuring reduction in size of solids
ES385173A1 (es) * 1969-11-05 1976-04-16 Wedag Wstfalia Dinnendhl Gropp Procedimiento para la regulacion de una instalacion de mol-turacion con gran rendimiento de paso.
US4611763A (en) * 1981-05-27 1986-09-16 Sankyo Dengyo Co. Ltd. Method and apparatus for controlling a grinding mill
US20030038198A1 (en) * 2001-05-31 2003-02-27 Starkey Associates Grinding Design And Process Engineering Ball mill
US20050223798A1 (en) * 2004-04-08 2005-10-13 Starkey John H Testing method for ball mills
US20090199625A1 (en) * 2006-05-18 2009-08-13 The University Of Queensland Apparatus for Determining Breakage Properties of Particulate Material

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021248233A1 (fr) * 2020-06-11 2021-12-16 Starkey & Associates Inc. Broyeur semi-autogène (sag) continu à l'échelle du laboratoire
GB2610980A (en) * 2020-06-11 2023-03-22 Starkey & Ass Inc Lab-scale continuous semi-autogenous (SAG) Grinding mill
GB2610980B (en) * 2020-06-11 2024-04-03 Starkey & Ass Inc Lab-scale continuous semi-autogenous (SAG) Grinding mill

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WO2013038367A3 (fr) 2013-06-27
CL2011002292A1 (es) 2012-01-20

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