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1
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1478
VIEWS
Started by Venkatesh
Propose to employ free floating grinding roller instead of balls or rods in a ball mill. Can we run the mill at 150 to 200 percent critical speed? How to assess the mill drive power in this case? Any formula? Air flow through the mill can be up to 4 ...
Propose to employ free floating grinding roller instead of balls or rods in a ball mill. Can we run the mill at 150 to 200 percent critical speed? How to assess the mill drive power in this case? Any formula? Air flow through the mill can be up to 4 ...
5
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3271
VIEWS
Started by Maya Rothman
Hello, Of the gold produced at some mines, 4 per cent of the total was recovered from the ball mills and classifiers when the mills were relined. I hear that much gold can get trapping in the grinding mill liners of SAG, Rod mills or even Ball mill...
Hello, Of the gold produced at some mines, 4 per cent of the total was recovered from the ball mills and classifiers when the mills were relined. I hear that much gold can get trapping in the grinding mill liners of SAG, Rod mills or even Ball mill...
Last replied to by David
https://www.youtube.com/watch?v=-zF8apw5jPc
https://www.youtube.com/watch?v=-zF8apw5jPc
4
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3479
VIEWS
Started by SAKAR
i am designing rubber lining for ball mill with below given operating condition can you please suggest me approximate thickness of shell liners and lifter bar ? OPERATING CONDITIONS: 1. MATERIAL ...
i am designing rubber lining for ball mill with below given operating condition can you please suggest me approximate thickness of shell liners and lifter bar ? OPERATING CONDITIONS: 1. MATERIAL ...
Last replied to by David
Same profile. Just increase the spacing at the shell/head joint. See this photo of inside a ball mill and its liner arrangement.
Same profile. Just increase the spacing at the shell/head joint. See this photo of inside a ball mill and its liner arrangement.
4
REPLIES
1760
VIEWS
Started by Shahid Rind
How do I increase d 50 value for caco3 45 micron in ball mill? What are the parameters for ball mill to making d 50 value 10 to 13. We are running CaCO3 45 um in ball mill but D50 value is not increasing more than 8 for making more coarser. I also...
How do I increase d 50 value for caco3 45 micron in ball mill? What are the parameters for ball mill to making d 50 value 10 to 13. We are running CaCO3 45 um in ball mill but D50 value is not increasing more than 8 for making more coarser. I also...
Last replied to by
Shahid Rind answer the questions we need to help you and try increasing your classifier density. Read https://www.911metallurgist.com/blog/spiral-classifier-for-mineral-processing and https://www...
Shahid Rind answer the questions we need to help you and try increasing your classifier density. Read https://www.911metallurgist.com/blog/spiral-classifier-for-mineral-processing and https://www...
3
REPLIES
2775
VIEWS
Started by mohamedkrafi
Dear sir; I want to design the ROM ball mill (it's same of ball mill but it can accept the big size until 150mm): are there some process limitation for this technology? is it possible to design ROM ball mill (1 stage) from D80=100 mm to ...
Dear sir; I want to design the ROM ball mill (it's same of ball mill but it can accept the big size until 150mm): are there some process limitation for this technology? is it possible to design ROM ball mill (1 stage) from D80=100 mm to ...
5
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3687
VIEWS
Started by levina pangani
I want to optimize the grinding circuit so as to improve gravity and grind size. What may be the main factors should I consider in order to achieve my project. The recirculating load in the plant is 400% and type of the ore processed is the mixed sul...
I want to optimize the grinding circuit so as to improve gravity and grind size. What may be the main factors should I consider in order to achieve my project. The recirculating load in the plant is 400% and type of the ore processed is the mixed sul...
Last replied to by Charlie
https://www.scribd.com/user/161408287/Cristian-Dosque-Munoz
https://www.scribd.com/user/161408287/Cristian-Dosque-Munoz
7
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3804
VIEWS
Started by
what is better for classification of copper up to 75 micron size whether to use spiral classifier or hydrocyclone
what is better for classification of copper up to 75 micron size whether to use spiral classifier or hydrocyclone
Last replied to by David
A friend familiar with this told me the main problem with spiral classifiers is the cut size is directly proportional to retention time (flow rate, Stoke's law, that sort of thing). To get a fine c...
A friend familiar with this told me the main problem with spiral classifiers is the cut size is directly proportional to retention time (flow rate, Stoke's law, that sort of thing). To get a fine c...
13
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5963
VIEWS
Started by mohamedkrafi
I have lot of scats in overflow ball please help if I transformed overflow ball in grate discharge ball mill I will less scats production or not? (D80=10mm, P80=140 microns)
I have lot of scats in overflow ball please help if I transformed overflow ball in grate discharge ball mill I will less scats production or not? (D80=10mm, P80=140 microns)
5
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2044
VIEWS
Started by glocmines
Does making the ball mill close circuit, reduce its P80. (e.g letting the hydrocyclone produce an overflow of 130 um). this would mean, most of the pulp will go to the underflow. If we do this, what is the limit for the circulating load? The proble...
Does making the ball mill close circuit, reduce its P80. (e.g letting the hydrocyclone produce an overflow of 130 um). this would mean, most of the pulp will go to the underflow. If we do this, what is the limit for the circulating load? The proble...
2
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1566
VIEWS
Started by ricardo.pascor
If I have a ball mill 6x12, I wish to get better energy consumption, then It is possible to get when I change the trunnion bearing by roller bearing for mill grinding application? If it is possible, which is the percentage (%) to save from the act...
If I have a ball mill 6x12, I wish to get better energy consumption, then It is possible to get when I change the trunnion bearing by roller bearing for mill grinding application? If it is possible, which is the percentage (%) to save from the act...
Last replied to by raghdmuhi
dear, I didnt understand the question.
dear, I didnt understand the question.
2
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10729
VIEWS
Started by randzzzzzzzzzz
How did you derived the formula for the critical speed of the ball mill?
How did you derived the formula for the critical speed of the ball mill?
Last replied to by
When the ball mill rotates at the critical speed the theoretical trajectory of the charge is such that it would fall outside the shell as centrifuging occur at this stage and the medium is carried aro...
When the ball mill rotates at the critical speed the theoretical trajectory of the charge is such that it would fall outside the shell as centrifuging occur at this stage and the medium is carried aro...
1
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1414
VIEWS
Started by Hauptsturm
I am currently working on a study with a client on alternative Grinding Circuit energy intensity quantification methods based on the approaches in http://www.ceecthefuture.org. I came across your articles https://www.911metallurgist.com/blog/bond-i...
I am currently working on a study with a client on alternative Grinding Circuit energy intensity quantification methods based on the approaches in http://www.ceecthefuture.org. I came across your articles https://www.911metallurgist.com/blog/bond-i...
Last replied to by Alex Doll
Short answer is yes, the SMC test is one way that you can "benchmark" an operating mill against a theoretical power consumption for a "typical" grinding circuit. There is another method using Bond-ty...
Short answer is yes, the SMC test is one way that you can "benchmark" an operating mill against a theoretical power consumption for a "typical" grinding circuit. There is another method using Bond-ty...
1
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1982
VIEWS
Started by kocgium
Hi guys, I am new in the mining world, yesterday i was in a meeting with a lot of metallurgist, and all of them agree with this sentence: " we design the plant so that grinding/milling area is the bottleneck " Why is that or why the bottleneck c...
Hi guys, I am new in the mining world, yesterday i was in a meeting with a lot of metallurgist, and all of them agree with this sentence: " we design the plant so that grinding/milling area is the bottleneck " Why is that or why the bottleneck c...
4
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3725
VIEWS
Started by alaz
hello every one 1- i am working in gold plant and my co-worker calling the sag mill Pebble mill and i searched in google then i found sag mill is not same as Pebble mill if you can help me and explain the different to me i will be happy. 2- i...
hello every one 1- i am working in gold plant and my co-worker calling the sag mill Pebble mill and i searched in google then i found sag mill is not same as Pebble mill if you can help me and explain the different to me i will be happy. 2- i...
4
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3897
VIEWS
Started by Subhash-Kumar-Roy
Yesterday I calculated the power draw of our ball mill. I attach a graph of it. Is it possible to have calculated mill power draw to be greater than mill motor HP? Calculated mill power draw is 1,509 HP Mill motor HP is 1,500 HP Accordin...
Yesterday I calculated the power draw of our ball mill. I attach a graph of it. Is it possible to have calculated mill power draw to be greater than mill motor HP? Calculated mill power draw is 1,509 HP Mill motor HP is 1,500 HP Accordin...
Last replied to by Subhash-Kumar-Roy
Thanks everyone. I realize I had forgotten to detect the mill liners from my mill's dimensions. Therefore yes, my model was incorrect. This change results in a in the diameter going from 13.5 ft to ...
Thanks everyone. I realize I had forgotten to detect the mill liners from my mill's dimensions. Therefore yes, my model was incorrect. This change results in a in the diameter going from 13.5 ft to ...
4
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2715
VIEWS
Started by maino.kaupa
What can i do to get best grind sizing in the mill: add water? decrease water? add more balls? Speed up mill? or what more to do?
What can i do to get best grind sizing in the mill: add water? decrease water? add more balls? Speed up mill? or what more to do?
Last replied to by David
Also see https://www.911metallurgist.com/grinding/interpretation-of-power-draw/
Also see https://www.911metallurgist.com/grinding/interpretation-of-power-draw/
6
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4750
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2
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1890
VIEWS
Started by banyechan
Why should high chrome casting balls be only choice using in Platinum ore grinding? We know that both forged and casting balls are used in gold and copper mines, but we are wondering why the high chrome casting balls only choice in Platinum? Could ...
Why should high chrome casting balls be only choice using in Platinum ore grinding? We know that both forged and casting balls are used in gold and copper mines, but we are wondering why the high chrome casting balls only choice in Platinum? Could ...
4
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1917
VIEWS
Started by vekian
Is there a table/explanation/diagram or similar that exists online that explains in a simple format, how to interpret a graph/trend of power draw/KW/load. eg. what the trend/graph would look like if a ball mill has too much or not enough water, or if...
Is there a table/explanation/diagram or similar that exists online that explains in a simple format, how to interpret a graph/trend of power draw/KW/load. eg. what the trend/graph would look like if a ball mill has too much or not enough water, or if...
1
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5056
VIEWS
Started by Takue
How to compare a ball mill and wet pan mill in terms of energy consumption and efficiency in gold processing.
How to compare a ball mill and wet pan mill in terms of energy consumption and efficiency in gold processing.
Last replied to by David
Hello Takue and welcome to the forum. You know Arrastres, Chilean mills, and Huntington mills are types of pan mills. A Hardinge mill is a type of ball mill that was around in the days of pan mills...
Hello Takue and welcome to the forum. You know Arrastres, Chilean mills, and Huntington mills are types of pan mills. A Hardinge mill is a type of ball mill that was around in the days of pan mills...
4
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3557
VIEWS
Started by jamesd
How to establish a mass balance and derive the circulation load of a closed circuit given the specific gravities of the mill discharge to classifier, underflow and overflow from the classifier? An iron ore company milled ore at the rate of 150 t/h i...
How to establish a mass balance and derive the circulation load of a closed circuit given the specific gravities of the mill discharge to classifier, underflow and overflow from the classifier? An iron ore company milled ore at the rate of 150 t/h i...
Last replied to by
I need lots of details on your situation...otherwise just read https://www.scribd.com/doc/293372742/Mineral-Comminution-Circuits-Their-Operation-and-Optimisation-T-J-Napier-Munn-S-Morrell
I need lots of details on your situation...otherwise just read https://www.scribd.com/doc/293372742/Mineral-Comminution-Circuits-Their-Operation-and-Optimisation-T-J-Napier-Munn-S-Morrell
4
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2387
VIEWS
Started by Maya Rothman
Hello, in calculating the top size of grinding media for a ball mill, there are 2 methods/formulas (Fred C. Bond) and AZZARONI's. Am looking at a ball mill F80 1248um and 8m diameter, 78% Cs, BWi 14.3 and SG 3 Azzaroni's ball calc is almost 2X the...
Hello, in calculating the top size of grinding media for a ball mill, there are 2 methods/formulas (Fred C. Bond) and AZZARONI's. Am looking at a ball mill F80 1248um and 8m diameter, 78% Cs, BWi 14.3 and SG 3 Azzaroni's ball calc is almost 2X the...
Last replied to by Greg Henderson
Alex Doll is right in that these equations are based on empirical data and experimentation or benchmarking with mills processing similar ore is perhaps more practical. Another consideration is re...
Alex Doll is right in that these equations are based on empirical data and experimentation or benchmarking with mills processing similar ore is perhaps more practical. Another consideration is re...
8
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1710
VIEWS
Started by JOHN
Hello guys. I really need your expertise advice and ideas. The plant I work for is a gold processing plant. They have a real problem with the pumps from cyclone underflow to ball mill. The mill section comprises a ball mill, screen and cyclone. I ...
Hello guys. I really need your expertise advice and ideas. The plant I work for is a gold processing plant. They have a real problem with the pumps from cyclone underflow to ball mill. The mill section comprises a ball mill, screen and cyclone. I ...
2
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2464
VIEWS
Started by jerry andoh
Currently my SAG mill load cells aren't working so the quest is how to run the mill with only power draw indication. Assistance will be much appreciated. Jerry
Currently my SAG mill load cells aren't working so the quest is how to run the mill with only power draw indication. Assistance will be much appreciated. Jerry
2
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1385
VIEWS
Started by Charlie
Hi, If I calculated the grinding ball I need on this ball mill grinding circuit to be about 1/2 the diameter of the ball this mill is already using, is there a way to estimate the grinding efficiency gains I could expect of switching to that smalle...
Hi, If I calculated the grinding ball I need on this ball mill grinding circuit to be about 1/2 the diameter of the ball this mill is already using, is there a way to estimate the grinding efficiency gains I could expect of switching to that smalle...
9
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7590
VIEWS
Started by hllopez
What is the most reliable method to determine actual circulating load in grinding circuit? A simple one - ball mill w/ hydrocyclone. I observed that the most common methods applied are (1) use of water balance - taking samples of cyclone feed, c...
What is the most reliable method to determine actual circulating load in grinding circuit? A simple one - ball mill w/ hydrocyclone. I observed that the most common methods applied are (1) use of water balance - taking samples of cyclone feed, c...
Last replied to by David
Hi mlticzon, Welcome to 911Met and thanks for this useful question. This is one of those learn by reading/doing/trying. Have a good look at https://www.911metallurgist.com/blog/moly-cop-tools-downlo...
Hi mlticzon, Welcome to 911Met and thanks for this useful question. This is one of those learn by reading/doing/trying. Have a good look at https://www.911metallurgist.com/blog/moly-cop-tools-downlo...
1
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2554
VIEWS
Started by Gh99
I am a new in an iron ore plant were we are with magnetite ore using two Aerofall Mills but it's very hard for us to control the the mill feed rate, and we also have a problem with the Ball charge; we've tried different charges but it's still a prob...
I am a new in an iron ore plant were we are with magnetite ore using two Aerofall Mills but it's very hard for us to control the the mill feed rate, and we also have a problem with the Ball charge; we've tried different charges but it's still a prob...
Last commented on by Alex Doll
Big rocks need big balls to grind effectively. Small rocks need small balls to grind effectively.
Big rocks need big balls to grind effectively. Small rocks need small balls to grind effectively.
4
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2471
VIEWS
Started by Jose Ruiz
Hi, I have the following situation: Magnetite ore with a work index wi=10.2 kWh/t feed= 100t/h f80= 4000 microns p80= 40 microns . The question we have: is possible for just a single VM 3000 and cyclones to handle this condition + the ...
Hi, I have the following situation: Magnetite ore with a work index wi=10.2 kWh/t feed= 100t/h f80= 4000 microns p80= 40 microns . The question we have: is possible for just a single VM 3000 and cyclones to handle this condition + the ...
8
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2021
VIEWS
Started by antz001
If one has a low ball charge in a ball mill, what advice would you suggest? We do not add steel balls to the mill, thus the grind is too coarse. I am responsible for the metallurgical plant. The people above me just wants "tons"! I know what to do! I...
If one has a low ball charge in a ball mill, what advice would you suggest? We do not add steel balls to the mill, thus the grind is too coarse. I am responsible for the metallurgical plant. The people above me just wants "tons"! I know what to do! I...
Last replied to by David
Anthony, What size material are in feeding into your first ball mill? "It was advised not to operate the motor more than 75% of its design capacity" who is "it" that has set that 75% power limit?...
Anthony, What size material are in feeding into your first ball mill? "It was advised not to operate the motor more than 75% of its design capacity" who is "it" that has set that 75% power limit?...
9
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4055
VIEWS
Started by spaceexplorer
I need help in selecting the ideal hydrocyclone(s) for our intended application. Any suggestion would be greatly appreciated. The contemplated project involves the reconcentration of old tailing piles, using centrifugal concentrator, such as the ICO...
I need help in selecting the ideal hydrocyclone(s) for our intended application. Any suggestion would be greatly appreciated. The contemplated project involves the reconcentration of old tailing piles, using centrifugal concentrator, such as the ICO...
Last commented on by spaceexplorer
Hi JPearcy. Thanks for your comments and suggestions. I have already started looking into the Krebs D15 hydrocyclone and a possible cluster od D6 hydrocyclone. I will keep you posted on my findings. Y...
Hi JPearcy. Thanks for your comments and suggestions. I have already started looking into the Krebs D15 hydrocyclone and a possible cluster od D6 hydrocyclone. I will keep you posted on my findings. Y...
https://www.911metallurgist.com/blog/quick-grind-check-how-to-quickly-estimate-grind-size-or-p80