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4
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3133
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Started by
Has anyone had any experience with the Outotec MillSense real-time mill charge analyzer? It is a very innovative approach but does it work? Are you using it for day to day decision making?
Has anyone had any experience with the Outotec MillSense real-time mill charge analyzer? It is a very innovative approach but does it work? Are you using it for day to day decision making?
2
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4390
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Started by
What may be the probable reason of high temperature in slide shoe bearings of cement mill?
What may be the probable reason of high temperature in slide shoe bearings of cement mill?
4
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3163
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Started by
Through continuous improvement and the use of advanced technologies like SmartEar™, Pueblo Viejo are improving the control and operation of their SAG mill, resulting in reduced liner wear, more efficiency.Volume Title: 12th Mill Operators' Conferen...
Through continuous improvement and the use of advanced technologies like SmartEar™, Pueblo Viejo are improving the control and operation of their SAG mill, resulting in reduced liner wear, more efficiency.Volume Title: 12th Mill Operators' Conferen...
13
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3281
VIEWS
Started by Obersturmbann
A few years ago, McGill University in Canada developed a new and more accurate test methodology for predicting steel media consumption. This test (Steel Media Wear Test) is licensed and currently being offered commercially by JKTech. The test also ha...
A few years ago, McGill University in Canada developed a new and more accurate test methodology for predicting steel media consumption. This test (Steel Media Wear Test) is licensed and currently being offered commercially by JKTech. The test also ha...
17
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3946
VIEWS
Started by Victor Bergman
Whether it is practical and/or worthwhile to run a Bond Ball Mill Work Index test at 500 mesh (25 micron)? Are there calculation alternatives? This would be for sizing of fine grinding or regrind mills.
Whether it is practical and/or worthwhile to run a Bond Ball Mill Work Index test at 500 mesh (25 micron)? Are there calculation alternatives? This would be for sizing of fine grinding or regrind mills.
Last replied to by Obersturmbann
We use grind curves over a range of work inputs using stirred media mills to determine the kWh/t to achieve the desired final particle size distribution. This can be done down to the sub-micron sizes ...
We use grind curves over a range of work inputs using stirred media mills to determine the kWh/t to achieve the desired final particle size distribution. This can be done down to the sub-micron sizes ...
18
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2564
VIEWS
Started by Rahil Khan
What is your idea about space between SAG mill shell liners? How much space would be appropriate?
What is your idea about space between SAG mill shell liners? How much space would be appropriate?
22
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8477
VIEWS
Started by
What is the effect of low ball % full on grinding efficiency?One of our clients is thinking of the future and has bought a ball mill that will be the right size someday, but is very large now.I know what happens to mill power from adjustments to % cr...
What is the effect of low ball % full on grinding efficiency?One of our clients is thinking of the future and has bought a ball mill that will be the right size someday, but is very large now.I know what happens to mill power from adjustments to % cr...
1
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1613
VIEWS
Started by Helena Russell
How to estimate the necessary flow rate of air to feed a row of six flotation cells agitators?
How to estimate the necessary flow rate of air to feed a row of six flotation cells agitators?
Last replied to by Obersturmbann
Take a look at this article for an approach:Miguel Maldonado, Rodrigo Araya and James FinchAn Overview of Optimizing Strategies for Flotation BanksMinerals 2012, 2, 258-271; doi:10.3390/min2040258http...
Take a look at this article for an approach:Miguel Maldonado, Rodrigo Araya and James FinchAn Overview of Optimizing Strategies for Flotation BanksMinerals 2012, 2, 258-271; doi:10.3390/min2040258http...
2
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1664
VIEWS
Started by
We are facing a problem at vertical raw mill that mill not getting feed according to designed capacity all things ok. Please share your thinking according to your experience. And one more thing if, in a vertical raw mill operating manual, it is descr...
We are facing a problem at vertical raw mill that mill not getting feed according to designed capacity all things ok. Please share your thinking according to your experience. And one more thing if, in a vertical raw mill operating manual, it is descr...
Last replied to by Kumar Choudhry
Did you change new liner for table and grinding rollers? Could not get the meaning of all things ok, whether it was running with a designed capacity before?
Did you change new liner for table and grinding rollers? Could not get the meaning of all things ok, whether it was running with a designed capacity before?
1
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1279
VIEWS
Started by Zander Barcalow
A laboratory grindability test made in closed circuit! Should it be regarded as a miniature of a commercial mill operation? Should its performance be scaled-up to the size of a commercial mill?Does the screen analysis of its product and circulating l...
A laboratory grindability test made in closed circuit! Should it be regarded as a miniature of a commercial mill operation? Should its performance be scaled-up to the size of a commercial mill?Does the screen analysis of its product and circulating l...
Last replied to by Obersturmbann
In general, the closed-loop tests are laborious and time consuming. The grinding environment within the ball mill is a first complicating factor for the scale-up. The type of classification used, have...
In general, the closed-loop tests are laborious and time consuming. The grinding environment within the ball mill is a first complicating factor for the scale-up. The type of classification used, have...
2
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1636
VIEWS
Started by Hauptsturm
I am looking for some information about pressure drop in dry SAG mills? How designers calculate the requirement air flow rate for this kind of mills?
I am looking for some information about pressure drop in dry SAG mills? How designers calculate the requirement air flow rate for this kind of mills?
Last replied to by Subhash-Kumar-Roy
Pressure drop is the most important parameter in dry SAG mills because it can make material discharge possible. I depend on mill length and the amount of material in front of the max trunnion opening....
Pressure drop is the most important parameter in dry SAG mills because it can make material discharge possible. I depend on mill length and the amount of material in front of the max trunnion opening....
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1629
VIEWS
Started by
Is it true that the lifter release angle of recent installed SAG mills are more than 15 degrees? Will it be the future of lifter geometry and design?
Is it true that the lifter release angle of recent installed SAG mills are more than 15 degrees? Will it be the future of lifter geometry and design?
Last replied to by Hauptsturm
Here at MEPSA, we manufacture cast steel liners for OEM's. The latest profiles designs we are working for them, consider SAG's lifters release angles with angles between 20 and 30 degrees
Here at MEPSA, we manufacture cast steel liners for OEM's. The latest profiles designs we are working for them, consider SAG's lifters release angles with angles between 20 and 30 degrees
4
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1451
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Started by
Do you know if it’s possible to supply a mill with Squirrel Cage Induction Motor Drive using low tension motors (480V) instead MT? (4160V) when power requirement is less than 1000kw?
Do you know if it’s possible to supply a mill with Squirrel Cage Induction Motor Drive using low tension motors (480V) instead MT? (4160V) when power requirement is less than 1000kw?
Last replied to by Gruppen
Below 1000 kW it is not a big problem to operate the mill with a low voltage motor. The problem is the start-up, where you have 6-7x nominal ampere which is typically not possible for the start-up tim...
Below 1000 kW it is not a big problem to operate the mill with a low voltage motor. The problem is the start-up, where you have 6-7x nominal ampere which is typically not possible for the start-up tim...
24
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6727
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Started by
Is there a general rule or a formula to calculate the ideal %ball charge in a SAG mill?
Is there a general rule or a formula to calculate the ideal %ball charge in a SAG mill?
8
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2064
VIEWS
Started by Amar
What's your suggestion for best recommendation for aP80 of cyclone overflow for lead & zinc to feed a flotation circuit?
What's your suggestion for best recommendation for aP80 of cyclone overflow for lead & zinc to feed a flotation circuit?
Last replied to by Kumar Choudhry
It is obvious thing that the mineral beneficiation process is to enrich the interested mineral quantity in the concentrate. It directly derives from the optimum liberation of the minerals from the hos...
It is obvious thing that the mineral beneficiation process is to enrich the interested mineral quantity in the concentrate. It directly derives from the optimum liberation of the minerals from the hos...
12
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4897
VIEWS
Started by Subhash-Kumar-Roy
In a grinding circuit, is there any relationship between SAG mill % solids and P80 (SAG mill product)? And what is the optimum % solid for sag mill?
In a grinding circuit, is there any relationship between SAG mill % solids and P80 (SAG mill product)? And what is the optimum % solid for sag mill?
Last replied to by Sandeep Bisht
Relation between Sag mill solid and product P80!Both are dependent on feed size. Dependent on Volume % solids in SAG mill. Dependent on ball charge volume. Hardness of ore. Recirculation load. De...
Relation between Sag mill solid and product P80!Both are dependent on feed size. Dependent on Volume % solids in SAG mill. Dependent on ball charge volume. Hardness of ore. Recirculation load. De...
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1459
VIEWS
Started by Unterstarm
Do the chemicals of grinding balls have any effect on the final processed product? What's the key chemical element of grinding balls affects the processed final products?
Do the chemicals of grinding balls have any effect on the final processed product? What's the key chemical element of grinding balls affects the processed final products?
Last replied to by Sandeep Bisht
•High chrome ball wear is less by 50% than hyper steel balls.•Contribution of wear in flotation is negligible. It is the shape of ball till disintegration to zero is the contributing factor. The m...
•High chrome ball wear is less by 50% than hyper steel balls.•Contribution of wear in flotation is negligible. It is the shape of ball till disintegration to zero is the contributing factor. The m...
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1875
VIEWS
Started by Obergruppenfuhrer
As a comparison between Ball mill and Gyratory mill for potash plant, which one is better? (With the aim of reducing fine particles)
As a comparison between Ball mill and Gyratory mill for potash plant, which one is better? (With the aim of reducing fine particles)
Last replied to by Sudhirkumar
Ball mills: They are used for coarser grinding. Mostly wet grinding. Wet process means multiple handling and more cost. Very rarely used for dry grinding. Cement, pellet feed. etc.Gyratory: It is used...
Ball mills: They are used for coarser grinding. Mostly wet grinding. Wet process means multiple handling and more cost. Very rarely used for dry grinding. Cement, pellet feed. etc.Gyratory: It is used...
3
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1901
VIEWS
Started by Rahil Khan
Does anyone know about determining the breakage function of SAG Mill using JKMRC method and determining the b(i,j) for all sizes.
Does anyone know about determining the breakage function of SAG Mill using JKMRC method and determining the b(i,j) for all sizes.
Last replied to by Maya Rothman
If you want to determine your breakage and selection function for any current operation you can use our Moly-Cop Tools SAG Model, we have an Excel routine to get your parameters, then you can use this...
If you want to determine your breakage and selection function for any current operation you can use our Moly-Cop Tools SAG Model, we have an Excel routine to get your parameters, then you can use this...
3
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1837
VIEWS
Started by
Apart from Bond's EF factors (CA Rowland), what other scale-up factors are applied to lab BWI for large-scale ball mill sizing?
Apart from Bond's EF factors (CA Rowland), what other scale-up factors are applied to lab BWI for large-scale ball mill sizing?
Last replied to by Maya Rothman
The EF factors are usually sufficient to size a large ball mill. There used to be a discussion in the industry about whether they were suitable above, if I remember correctly, 18 ft diameter. That dis...
The EF factors are usually sufficient to size a large ball mill. There used to be a discussion in the industry about whether they were suitable above, if I remember correctly, 18 ft diameter. That dis...
4
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2294
VIEWS
Started by Oberstorm
A laboratory grindability test made in closed circuit. Should it be regarded as a miniature of a commercial mill operation? Should its performance be scaled- up to the size of a commercial mill?Does the screen analysis of its product and circulating ...
A laboratory grindability test made in closed circuit. Should it be regarded as a miniature of a commercial mill operation? Should its performance be scaled- up to the size of a commercial mill?Does the screen analysis of its product and circulating ...
11
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4314
VIEWS
Started by
Which power model is the most efficient to predict the correct power consumption in sag mill with change in process variables?I have developed a few dynamic simulators for different mineral/metal processing plants. Prediction of correct sag mill powe...
Which power model is the most efficient to predict the correct power consumption in sag mill with change in process variables?I have developed a few dynamic simulators for different mineral/metal processing plants. Prediction of correct sag mill powe...
Last commented on by David
Do you have a grizzly ahead of you jaw crusher? What openning? Are you able to post a few photos of your working crusher? Ore pocket? Working crusher cavity? What about your coarse ore stockpile; d...
Do you have a grizzly ahead of you jaw crusher? What openning? Are you able to post a few photos of your working crusher? Ore pocket? Working crusher cavity? What about your coarse ore stockpile; d...
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2470
VIEWS
Started by Maya Rothman
Last commented on by David
Example signature plot https://redesign.911metallurgist.com/blog/ultrafine-grinding-test-report-isamill-signature-plot
Example signature plot https://redesign.911metallurgist.com/blog/ultrafine-grinding-test-report-isamill-signature-plot
1
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3569
VIEWS
Started by
Is the JK rock hardness method specifically A*b patented?Actually I want to know if I am able to define it myself and report it in a paper or not.
Is the JK rock hardness method specifically A*b patented?Actually I want to know if I am able to define it myself and report it in a paper or not.
3
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1897
VIEWS
Started by
For secondary grinding (Ball Mill), what discharge Configuration is ideal with regards to cost saving for atypical copper milling plant with a throughput of say 331dmt/h. Qualify the selection of your recommendation.
For secondary grinding (Ball Mill), what discharge Configuration is ideal with regards to cost saving for atypical copper milling plant with a throughput of say 331dmt/h. Qualify the selection of your recommendation.
64
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7154
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Started by
Hello: I would like to start a new discussion. When HPGR should be used instead of SAGs in a grinding circuit. What are the technical advantages, sensitivity to feed distribution, hardness of ore, efficiency etc? What are the trade-offs between SAG v...
Hello: I would like to start a new discussion. When HPGR should be used instead of SAGs in a grinding circuit. What are the technical advantages, sensitivity to feed distribution, hardness of ore, efficiency etc? What are the trade-offs between SAG v...
Last replied to by Unterstarm
Read:http://911Metallurgist.com/C/HPGR-SAG/Compare%20HPGR%20vs%20SAG%20USING%20THE%20SMC%20TEST-TO%20PREDICT%20COMMINUTION%20CIRCUIT%20PERFORMANCE.pdf http://911Metallurgist.com/C/HPGR-SAG/USE%20OF%20...
Read:http://911Metallurgist.com/C/HPGR-SAG/Compare%20HPGR%20vs%20SAG%20USING%20THE%20SMC%20TEST-TO%20PREDICT%20COMMINUTION%20CIRCUIT%20PERFORMANCE.pdf http://911Metallurgist.com/C/HPGR-SAG/USE%20OF%20...
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2390
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Started by
We recently converted a grate discharge type ball mill (size 5.7X8.6m) to an Overflow type. Before conversion, the ball level was 26%, and we were able to obtain a grind of 90%+ passing 75mic at a throughput of 350t/h. After conversion it’s a night...
We recently converted a grate discharge type ball mill (size 5.7X8.6m) to an Overflow type. Before conversion, the ball level was 26%, and we were able to obtain a grind of 90%+ passing 75mic at a throughput of 350t/h. After conversion it’s a night...
Last commented on by David
Thanks for this Johan
Thanks for this Johan
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4717
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Started by Standartenfurer
I’m looking for ideas to process the discarded material of a SAG mill. We have huge material stocks of this process that contains ore contaminated with metal balls and some scrap elements that makes it hard to process it on a crusher. I have seen a...
I’m looking for ideas to process the discarded material of a SAG mill. We have huge material stocks of this process that contains ore contaminated with metal balls and some scrap elements that makes it hard to process it on a crusher. I have seen a...
3
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3064
VIEWS
Started by
How to stop the leakage through seal ring and seal wiper in wet ball mill?
How to stop the leakage through seal ring and seal wiper in wet ball mill?
10
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2414
VIEWS
Started by Jean Rasczak
Auditing can be a key for continues improvement of mineral processing circuits specially grinding/comminution but every experts have their own way which might be achieved over the year by experience. It'll be perfect if everyone can make profit of t...
Auditing can be a key for continues improvement of mineral processing circuits specially grinding/comminution but every experts have their own way which might be achieved over the year by experience. It'll be perfect if everyone can make profit of t...
2
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1706
VIEWS
Started by
Interesting article link below, it gives a new approach on how to measure assets productivity. I think is more "real" than OEE. For commutation normally I would use a logic where OEE = (availability or run-time) * (Avg TPD/max TPD) * (recovery %). Th...
Interesting article link below, it gives a new approach on how to measure assets productivity. I think is more "real" than OEE. For commutation normally I would use a logic where OEE = (availability or run-time) * (Avg TPD/max TPD) * (recovery %). Th...
Last replied to by Jean Rasczak
Wrong metrics in my view. This thinking leads us along the mindless treadmill of more volumes and higher utilizations which are guaranteed to maximize (total) costs, even though they create an illusio...
Wrong metrics in my view. This thinking leads us along the mindless treadmill of more volumes and higher utilizations which are guaranteed to maximize (total) costs, even though they create an illusio...
10
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3095
VIEWS
Started by
As a grinding media designer/supplier SGI considers that an MBT is not the best method for media selection.Do marked ball tests help determine if you have selected the best media for you mill?
As a grinding media designer/supplier SGI considers that an MBT is not the best method for media selection.Do marked ball tests help determine if you have selected the best media for you mill?
5
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1439
VIEWS
Started by Maya Rothman
Deseocalcular el consumo de bolas diarias para losmolinos de bolas y sag, tengo el consumo de kg de bolas /tmineral; el tonelaje de mineral a considerar para loscálculoses la cargafresca o la carga total que vamoler (esdecircargafresca + cargacircul...
Deseocalcular el consumo de bolas diarias para losmolinos de bolas y sag, tengo el consumo de kg de bolas /tmineral; el tonelaje de mineral a considerar para loscálculoses la cargafresca o la carga total que vamoler (esdecircargafresca + cargacircul...
1
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6851
VIEWS
Started by
The crop load of ball mill. It =ore + mill medium +water. But usually, it was used in a percentage formation. So how to calculate this percentage. I know this is really a basic question, but it puzzled me, for most books and papers just use it but no...
The crop load of ball mill. It =ore + mill medium +water. But usually, it was used in a percentage formation. So how to calculate this percentage. I know this is really a basic question, but it puzzled me, for most books and papers just use it but no...
Last replied to by Paul Morrow
The ball charge and ore charge volume is a variable, subject to what is the target for that operation. The type of mill also is a factor as if it is an overflow mill (subject to the diameter of the di...
The ball charge and ore charge volume is a variable, subject to what is the target for that operation. The type of mill also is a factor as if it is an overflow mill (subject to the diameter of the di...
Hello everyone I'm sorry to bring the topic from the ashes but i need some help here too The question is that we have two ballmills and they couldn't work together because the millsense system is wo...