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5
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2842
VIEWS
Started by Usman Konneh
Hello everyone, I was given the responsibility of testing the cyclone efficiency of the process plant. Our current operation required percentage should be 80% passing the 75um screen. What should I do as a Metallurgical Laboratory Technician to meet...
Hello everyone, I was given the responsibility of testing the cyclone efficiency of the process plant. Our current operation required percentage should be 80% passing the 75um screen. What should I do as a Metallurgical Laboratory Technician to meet...
13
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4236
VIEWS
Started by longz
I am working in a plant with single stage grinding using a ball mill we operate the mill power at around 1400KW& the feed size is 20mm. we use 78mm/64mm steel balls. the ball mill is in closed circuit with classification cyclones. there are 3 cyclone...
I am working in a plant with single stage grinding using a ball mill we operate the mill power at around 1400KW& the feed size is 20mm. we use 78mm/64mm steel balls. the ball mill is in closed circuit with classification cyclones. there are 3 cyclone...
1
REPLY
1867
VIEWS
Started by mran haider
Why cement grinding ball mill is floating towards the Gear box (MAAG) which has resulted the damage of the second stage of gear box. As we have replaced the gear box now but still we are unable to find out the solution how to control the mill which i...
Why cement grinding ball mill is floating towards the Gear box (MAAG) which has resulted the damage of the second stage of gear box. As we have replaced the gear box now but still we are unable to find out the solution how to control the mill which i...
Last commented on by mran haider
Dear sir, we already have done the proper alignment by an Expert of the Gearbox as the Gearbox was newly installed & we have done alignment twice with Expert. Finally he quit that this is not an alig...
Dear sir, we already have done the proper alignment by an Expert of the Gearbox as the Gearbox was newly installed & we have done alignment twice with Expert. Finally he quit that this is not an alig...
9
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3065
VIEWS
Started by alaz
hello everyone my problem is we hardly get 80% smaller than 75µm we have a SAG mill and ball mill and we are running 300 TPH on the sag mill the pulp S.G is 1.8 the sag mill KW around 4500 and we are using 125 mm steel ball the ba...
hello everyone my problem is we hardly get 80% smaller than 75µm we have a SAG mill and ball mill and we are running 300 TPH on the sag mill the pulp S.G is 1.8 the sag mill KW around 4500 and we are using 125 mm steel ball the ba...
Last replied to by KRISHNADAS
The suggestion given by Richard is practical & I would also like to add thta- Please check your gratings in the SAG mill , maybe it is worn out and needs repair. Krishna
The suggestion given by Richard is practical & I would also like to add thta- Please check your gratings in the SAG mill , maybe it is worn out and needs repair. Krishna
3
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1598
VIEWS
Started by Hamid72
Hello everyone I'm hamid and from iran I am working in a plant. At our plant we have a ball mill that grinds the strontium carbonate. this material is sticky and makes the mill choke. The informations of our mill are: Diameter: 76 cm Length: 282 ...
Hello everyone I'm hamid and from iran I am working in a plant. At our plant we have a ball mill that grinds the strontium carbonate. this material is sticky and makes the mill choke. The informations of our mill are: Diameter: 76 cm Length: 282 ...
1
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1473
VIEWS
Started by Shashank
What are the reasons of failure of viton rubber plugs in a ball mill? Can iron fines produced during dry grinding accelerate the process of rubber failure? One of the reasons will be self hardening due to continuous exposure to high temperature. Alt...
What are the reasons of failure of viton rubber plugs in a ball mill? Can iron fines produced during dry grinding accelerate the process of rubber failure? One of the reasons will be self hardening due to continuous exposure to high temperature. Alt...
Last replied to by David
How long do they take to fail?
How long do they take to fail?
2
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1923
VIEWS
Started by Pablo
Hello, I'm working on a project involving a ISAMILL LME4 (I do not have the machine right know). I'd like to know which phenomenon is predominant when it comes to size reduction of my ore. F80 = 75um Media size = 1.5mm diameter of the mill : 30cm...
Hello, I'm working on a project involving a ISAMILL LME4 (I do not have the machine right know). I'd like to know which phenomenon is predominant when it comes to size reduction of my ore. F80 = 75um Media size = 1.5mm diameter of the mill : 30cm...
2
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1486
VIEWS
Started by hovan
Greetings there, I work at a phosphoric acid plant where we have a ball mill. Recently the mill has not been producing enough output, this is due to not being able to increase amount of ore going into the mill as air circuit temperature is dropping,...
Greetings there, I work at a phosphoric acid plant where we have a ball mill. Recently the mill has not been producing enough output, this is due to not being able to increase amount of ore going into the mill as air circuit temperature is dropping,...
Last replied to by MineralFrothFlotation
Dear Hovan , Are you having a hot air generator in the grinding circuit if so just try to operate it at earlier temperature when mill was running smoothly . i.e analyze the crude first . Are you o...
Dear Hovan , Are you having a hot air generator in the grinding circuit if so just try to operate it at earlier temperature when mill was running smoothly . i.e analyze the crude first . Are you o...
3
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1937
VIEWS
Started by Hamid72
I am from Iran and I am student in mineral processing. I can't understand these sentences about Hydrocyclone pressure drop at overflow. can you explain me easier? thank you so much Should the overflow be discharged against a positive head, some of ...
I am from Iran and I am student in mineral processing. I can't understand these sentences about Hydrocyclone pressure drop at overflow. can you explain me easier? thank you so much Should the overflow be discharged against a positive head, some of ...
4
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1459
VIEWS
Started by Helen
Hello all... I found out the scales forming are that of carbonate due to the lime and hardness of the process water. A little confusion i have is how can very large scales of carbonate form on a highly agitating component? the vibrating screen agit...
Hello all... I found out the scales forming are that of carbonate due to the lime and hardness of the process water. A little confusion i have is how can very large scales of carbonate form on a highly agitating component? the vibrating screen agit...
8
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1670
VIEWS
Started by Helen
Hello, I work in a gold processing plant where we have a vibrating trash screen in our milling circuit made from a polywedge material. We have a considerable amount of thin scales forming on the screens which are removed every shut down with Sulphami...
Hello, I work in a gold processing plant where we have a vibrating trash screen in our milling circuit made from a polywedge material. We have a considerable amount of thin scales forming on the screens which are removed every shut down with Sulphami...
Last replied to by Stewart Fernandez
I did a bit of poking around and I wonder if you are using that sort of screen layout, cause if you are - there is absolutely no surprise that you are having issues, that will not work - its way to ...
I did a bit of poking around and I wonder if you are using that sort of screen layout, cause if you are - there is absolutely no surprise that you are having issues, that will not work - its way to ...
4
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1567
VIEWS
Started by banyechan
why lead zinc ore grinding mills prefering casting high chrome grinding balls not forged balls? Can anyone give me some ideas?
why lead zinc ore grinding mills prefering casting high chrome grinding balls not forged balls? Can anyone give me some ideas?
Last replied to by Metsol
Max is quite correct re: the chrome balls are harder but after some laboratory and plant work a few years ago it was clear that the forged balls have an adverse effect on the redox potential of the fe...
Max is quite correct re: the chrome balls are harder but after some laboratory and plant work a few years ago it was clear that the forged balls have an adverse effect on the redox potential of the fe...
1
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1439
VIEWS
Started by mebrahtu
1.Hello everyone.we have a FOS with a total capacity of around 3000tonnes. All the day at the end of every month we take the stock by deducting the total tonnes milled from total tonnes crushed of that month but this no longer continued bcz on time s...
1.Hello everyone.we have a FOS with a total capacity of around 3000tonnes. All the day at the end of every month we take the stock by deducting the total tonnes milled from total tonnes crushed of that month but this no longer continued bcz on time s...
1
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1591
VIEWS
Started by Mshindo jr
How does mill power draw affect grindability?
How does mill power draw affect grindability?
Last replied to by Mike Rockandel
Cart before the horse. The question I think should have been "How does grindability affect mill power draw". When you say grindability I assume that you mean, "How much size reduction can you achieve ...
Cart before the horse. The question I think should have been "How does grindability affect mill power draw". When you say grindability I assume that you mean, "How much size reduction can you achieve ...
2
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1537
VIEWS
Started by Johannes
We are attempting to successfully grind Micaceous iron oxide (Hematite) down to -63 micron average 40/50 micron but maintaining the bulk of its lamellar structure,platelets after grinding should show up red under a bottom lit microscope, any one had ...
We are attempting to successfully grind Micaceous iron oxide (Hematite) down to -63 micron average 40/50 micron but maintaining the bulk of its lamellar structure,platelets after grinding should show up red under a bottom lit microscope, any one had ...
2
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1514
VIEWS
Started by Langton
Am looking to design a 4 to 5 ton per hour dry ball mill. What factors should I be looking for? The following is what I have: Feed size 20mm, product size 75microns, Wi 16.5kWh/ton. I do not what want to use any water as its washing away a lot of ...
Am looking to design a 4 to 5 ton per hour dry ball mill. What factors should I be looking for? The following is what I have: Feed size 20mm, product size 75microns, Wi 16.5kWh/ton. I do not what want to use any water as its washing away a lot of ...
3
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1701
VIEWS
Started by Tony Johnston
Does anyone have a couple of examples where iron ore is being ground using a ball mill with an inverter for mill speed control? And if you do, can you offer any commentary on how successful, in technical and economic terms, that approach is proving ...
Does anyone have a couple of examples where iron ore is being ground using a ball mill with an inverter for mill speed control? And if you do, can you offer any commentary on how successful, in technical and economic terms, that approach is proving ...
Last replied to by David
My friend from https://sagmilling.com/ says most iron ore mines don't use ball mills for a couple of reasons: 1. The grind is coarse enough that you can do it in a single stage (Eg. Labrador Trench) ...
My friend from https://sagmilling.com/ says most iron ore mines don't use ball mills for a couple of reasons: 1. The grind is coarse enough that you can do it in a single stage (Eg. Labrador Trench) ...
4
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2603
VIEWS
Started by Simeon
How long would a hydrocyclone typically last (Barrel, lower cone, mid cone, spigot) before being worn out? It can be rubber lined, Polyurethane whatever material... When feeding rough like d50 1mm - 4mm ? High pressure range 90 - 120 kPa F...
How long would a hydrocyclone typically last (Barrel, lower cone, mid cone, spigot) before being worn out? It can be rubber lined, Polyurethane whatever material... When feeding rough like d50 1mm - 4mm ? High pressure range 90 - 120 kPa F...
5
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2299
VIEWS
Started by vekian
Hi people. I've put this idea by 2 metallurgists at the gold plant I work at. 1 agrees with me that it is worth trying. The other disagrees. They want a COF density target of 46 with a SG of 2.7. Extra water is needed to be added to the mill discha...
Hi people. I've put this idea by 2 metallurgists at the gold plant I work at. 1 agrees with me that it is worth trying. The other disagrees. They want a COF density target of 46 with a SG of 2.7. Extra water is needed to be added to the mill discha...
Last replied to by Dielgarcia
Vekian: Hi, can you tell me the thickener u/f?, if you have 46% in the COF, but, what density have in your CIL tanks?
Vekian: Hi, can you tell me the thickener u/f?, if you have 46% in the COF, but, what density have in your CIL tanks?
6
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1722
VIEWS
Started by Pabloski
Hello everyone, After the SAG mill there is a SAG box, where the output of the SAG is transferred into. There are 4 pumps (2 operational and 2 in stand-by) that transfers the material to a cyclones battery and then to two ball mills. When the ma...
Hello everyone, After the SAG mill there is a SAG box, where the output of the SAG is transferred into. There are 4 pumps (2 operational and 2 in stand-by) that transfers the material to a cyclones battery and then to two ball mills. When the ma...
4
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3354
VIEWS
Started by mohamedkrafi
I want know if you have an idea about the best comminution circuit selection basing on Ore hardness and competency (SABC, AG, ROMBALL MILL) we have two type of ore compétent and hard (AxB=24, ball work index = 18) and moderate and soft (AxB=40,...
I want know if you have an idea about the best comminution circuit selection basing on Ore hardness and competency (SABC, AG, ROMBALL MILL) we have two type of ore compétent and hard (AxB=24, ball work index = 18) and moderate and soft (AxB=40,...
3
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1489
VIEWS
Started by THIRU
Dear sir, We need grinding machine for grinding scrap of iron mill scale chips in size 25 mm width, thick 2 mm can be reduced into 1 to 2 mm powder. Also the iron mill scale chips contaminated with some another hardened iron lumps may thickness 10 ...
Dear sir, We need grinding machine for grinding scrap of iron mill scale chips in size 25 mm width, thick 2 mm can be reduced into 1 to 2 mm powder. Also the iron mill scale chips contaminated with some another hardened iron lumps may thickness 10 ...
1
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1391
VIEWS
Started by Fabian Rebolledo
I would like to know if there is some technologies that can measure the mass flow of an open channel that carries pulp from grinding and feeds milling
I would like to know if there is some technologies that can measure the mass flow of an open channel that carries pulp from grinding and feeds milling
Last replied to by OberstGruppen
Fabian, What are you trying to achieve?
Fabian, What are you trying to achieve?
3
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3201
VIEWS
Started by sajid
My grinding mill has length and diameter of 4.57 m. the maximum size of the balls selected is 77 mm, as there are two or three kinds of ball sizes used..how to select the second ball size. are there any formula or equation that i can calculate the ba...
My grinding mill has length and diameter of 4.57 m. the maximum size of the balls selected is 77 mm, as there are two or three kinds of ball sizes used..how to select the second ball size. are there any formula or equation that i can calculate the ba...
4
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3086
VIEWS
Started by Helena Russell
Is it the right practice to increase the density when too much material is reporting to the cyclone underflow for a diamond processing plant? Cyclone pressures were a bit down but within specs, manual and instrument densities were right but still too...
Is it the right practice to increase the density when too much material is reporting to the cyclone underflow for a diamond processing plant? Cyclone pressures were a bit down but within specs, manual and instrument densities were right but still too...
Last replied to by
If cyclone feed pressure and operating density are within acceptable ranges, you might want to have a look at the media density differentials. By measuring the feed and overflow stream densities you c...
If cyclone feed pressure and operating density are within acceptable ranges, you might want to have a look at the media density differentials. By measuring the feed and overflow stream densities you c...
1
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1441
VIEWS
Started by AR
How to decrease Copper lost in tail and what should upstream plant (grinding) to do to decrease Cu lost in tail ? Thanks you
How to decrease Copper lost in tail and what should upstream plant (grinding) to do to decrease Cu lost in tail ? Thanks you
3
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4158
VIEWS
Started by SAKAR
Dear Friends, Hi....I have one question about type of Wear Resistant Liner for Grinding mills. Why & Where to use metal Liner & Rubber liner ? I want to know about type of Grinding Mill Liners and where to use it.... Thanks & Good day. Jignesh
Dear Friends, Hi....I have one question about type of Wear Resistant Liner for Grinding mills. Why & Where to use metal Liner & Rubber liner ? I want to know about type of Grinding Mill Liners and where to use it.... Thanks & Good day. Jignesh
Last commented on by Alex Doll
FYI, the attachment Stuart provided is a chapter from the SME "Advances in Comminution" (Ed. S.K. Kawatra). It is a great book and I would recommend anyone interested in comminution pick up a copy of...
FYI, the attachment Stuart provided is a chapter from the SME "Advances in Comminution" (Ed. S.K. Kawatra). It is a great book and I would recommend anyone interested in comminution pick up a copy of...
1
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1470
VIEWS
Started by AR
What corellation between efficiency hydrocyclone and valuable mineral lost in tail? What corellation between grind size P80 overflow product of cyclone and valuable mineral lost in tail? Thank you
What corellation between efficiency hydrocyclone and valuable mineral lost in tail? What corellation between grind size P80 overflow product of cyclone and valuable mineral lost in tail? Thank you
Last replied to by Zander Barcalow
In a rougher flotation circuit: if you are more than 55-60% liberated on your target mineral = a coarser or finer P80 will not immediately matter. If you are say 80% liberated = coarser P80 may red...
In a rougher flotation circuit: if you are more than 55-60% liberated on your target mineral = a coarser or finer P80 will not immediately matter. If you are say 80% liberated = coarser P80 may red...
5
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1439
VIEWS
Started by Romain CADENAT
Dear All I have a hydrocyclone for which I need to send the overflow +1.5m above the head of the hydrocyclone. Is this configuration possible ? On the file attached I show standard configuration and the one I want. The feed pressure of the hyd...
Dear All I have a hydrocyclone for which I need to send the overflow +1.5m above the head of the hydrocyclone. Is this configuration possible ? On the file attached I show standard configuration and the one I want. The feed pressure of the hyd...
Last replied to by Romain CADENAT
Ok, thank you for your help Andrew. Thank you for the links Jean, interesting. In fact it is not a grinding circuit but a classification line.
Ok, thank you for your help Andrew. Thank you for the links Jean, interesting. In fact it is not a grinding circuit but a classification line.
7
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3403
VIEWS
Started by Ibrahim
Hello, We measured the thickness of sheet plate and lifter bar rubber liner in a ball mil for a gold mine to estimate when we have to change them. What is the minimum thickness of sheet plate to preserve the drum of the ball mil? And what is the mi...
Hello, We measured the thickness of sheet plate and lifter bar rubber liner in a ball mil for a gold mine to estimate when we have to change them. What is the minimum thickness of sheet plate to preserve the drum of the ball mil? And what is the mi...
Last commented on by David
It's about time you show up Stewart 🙂
It's about time you show up Stewart 🙂
2
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1564
VIEWS
Started by joy1484
We started our hammer mill (Williams mill) after doing several maintenance to solve some electric problems. The plan was to get in spec and then not make any adjustments and watch grind. With a starting grind of 76 (spec is 74-86) we let the mill go...
We started our hammer mill (Williams mill) after doing several maintenance to solve some electric problems. The plan was to get in spec and then not make any adjustments and watch grind. With a starting grind of 76 (spec is 74-86) we let the mill go...
3
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1403
VIEWS
Started by AR
What the correlation between throughput and grind size, throughput and power utilize, throughput and ore characteristic (WiBM), grind size and recovery Cu lost on tail? Thank you
What the correlation between throughput and grind size, throughput and power utilize, throughput and ore characteristic (WiBM), grind size and recovery Cu lost on tail? Thank you
5
REPLIES
3783
VIEWS
Started by Josh Wright
How does a "modified bond ball mill work index" test vary from a standard ball mill work index test?
How does a "modified bond ball mill work index" test vary from a standard ball mill work index test?
Last replied to by Josh Wright
Hi Dave, Peter, Chris, and Greg, Firstly, thank you so much for taking the time to reply. One of my colleagues mentioned that a recent RFQ requested a modified bond ball mill work index. We had susp...
Hi Dave, Peter, Chris, and Greg, Firstly, thank you so much for taking the time to reply. One of my colleagues mentioned that a recent RFQ requested a modified bond ball mill work index. We had susp...
1
REPLY
4160
VIEWS
Started by Takue
I need help in the determination of the power drawn by a wet pan mill in gold milling
I need help in the determination of the power drawn by a wet pan mill in gold milling
Last replied to by Alex Doll
Short answer is you measure the root-mean-square Amps and Volts going into the motor driving the mill, correct for the motor efficiency (and possibly power factor) and calculate power using equation P...
Short answer is you measure the root-mean-square Amps and Volts going into the motor driving the mill, correct for the motor efficiency (and possibly power factor) and calculate power using equation P...
1
REPLY
1568
VIEWS
Started by Shahid Rind
We are making silica flour in ball mill but production coming too much down because the main blower amperage downs from 50 ampere to 30 amp after giving feed material. I also checked the classifier, main blower motor, filter but still did'nt find ...
We are making silica flour in ball mill but production coming too much down because the main blower amperage downs from 50 ampere to 30 amp after giving feed material. I also checked the classifier, main blower motor, filter but still did'nt find ...
Last replied to by David
Have you closed off a duct? Amperage goes down as resistance to airflow increases. It is like free spinning. Is it possible the material you are feeding would block/restrict the airflow intake to you...
Have you closed off a duct? Amperage goes down as resistance to airflow increases. It is like free spinning. Is it possible the material you are feeding would block/restrict the airflow intake to you...
And could you please send me a sample spread sheet?