Grinding & Classification Circuits

Grinding & Classification Circuits2018-06-17T09:51:34-04:00
  • To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Grinding.
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

4
REPLIES
639
VIEWS
Started by epiphane
good evening friends, I need your help, I'm looking for a way to increase the life of the SAG liners. someone can help me find a solution to that. what study can I lead?
Last replied to by Shivam_Nigam
Hello Epiphane, were you able to get the info requested above for the guys.It will be important to know the Size of the Mill and especially the Liner Type with its present Wear Life. There are options...
3
REPLIES
757
VIEWS
Started by Hamid2017
Dear Specialists, I'm designing a ball mill circuit to grind the crushed gold ore from F80 9.5mm to P80 130 microns, simulation showed if we use one ball mill it would be 3m x 4.3m with 800hp motor, and if I use 2 ball mills with same power then eac...
Last replied to by NK
circuit one is best, circuit two although provides controlled production, its capital intensity, space required resulting in surging operational costs.if operational costs are managed well option 2 lo...
0
REPLIES
363
VIEWS
Started by Simba marshy
I want to to scale down a plant mill so that i can do simulations and grinding tests the plant overflow mill receives feed from only a classifier under flow at 260 t/h  and has  diameter 4.5m and length 6.3 m with ball charge of 33%   The lab mi...
0
REPLIES
395
VIEWS
Started by Rahul bhoraniya
I have attached clip of my ball mill which is turning on lathe. Is it really best method to increase vbelt life?  
2
REPLIES
900
VIEWS
Started by isqui
Hello, I was checking the Table of Ball Mill Index. Regarding the source 1 (Bond), I checked the source and the values are different. I thought the reason was that the values reported by Bond were in short ton instead of metric ton. However, ...
Last replied to by RayMartin
The number from Fred C in 1961 was an average of 10 determinations and the Table has the rider that values can vary for the same material from different sources.  Therefore it is only a guidline. Th...
1
REPLY
436
VIEWS
Started by Rahul bhoraniya
Please tell me which design of ceramic ball mill will be more effective to grind material in less time, energy efficient and economically good and best life?
Last replied to by SmartDog
Unfortunately your question is of the "what is the best car" variety.  You have left out too many key factors, because the answer (unfortunately) is "a properly sized one".  So what material are you...
5
REPLIES
523
VIEWS
Started by kfalus
Hello Dear Experts, I bought a new ball mill which's 900x3000 size. I am planning to grind river sand that has %60 silica in it's chemical proportion. But for me it's unnecessary to grind very fine like 600 micron or near, I just want to receive 0-3...
Last commented on by Morteza Mousavi
Hello guys. I read comments and i think it performs unsuitably. because of mill length it can not be possible.
2
REPLIES
481
VIEWS
Started by ritwik117
In a rod mill of diameter 3.8m I have three types of rod size distribution like 100 mm ,85mm ,70mm.In petcoke operation the vendor suggest that the wear rate is 52gms per ton of dry petcoke charged. I want to know the wear rate of individual rods lik...
Last commented on by SmartDog
Probably the best examples are from time management but use the basic principles see: https://www.youtube.com/watch?v=v5ZvL4as2y0
1
REPLY
361
VIEWS
Started by Rahul bhoraniya
I have ball mill which operates on gear motor. i want to to maintain 0 degree inside temperate inside and there is 68% alumina lining inside mill. ball mill rpm is 35. how can i make 0 degree temperature inside mill?  
Last commented on by Rahul bhoraniya
Can i see ball mill like you have told that small insulated box around mill? Thanks todd harvey.
3
REPLIES
634
VIEWS
Started by moayyad
i want to know we have ball mill for cement grinding the cooling water for mill bearing inter and exit in the same reading or higher in just one degree is these normal or we have problem and if we have problem what is the cause and the solution for t...
Last commented on by moayyad
I use portable temp sensors installed one used to give shoe bearing temp only and water pump works normally
1
REPLY
421
VIEWS
Started by babygenius76
I have a pendulum roller mill with closed circuit air classifier that is used for the dry fine grinding (d50--10 micron/ d97--18 micron) of calcium carbonate. The grinding mechanism of the pendulum roller mill does not rely significantly, to the bes...
Last replied to by adrianh
I'm puzzled that you can't change the feed rate. How is the feed rate controlled? I would have thought that providing a finer feed will allow you to increase the the feed rate to achieve the same prod...
2
REPLIES
462
VIEWS
Started by emilyfreire
The cyclone has a amount that pass to underflow and the other to overflow, the rolling load it will be the underflow mass divided by the feed. How can I control this, only by feed pressure or inside pressure in the cyclone?
Last replied to by Alex Doll
Get yourself one of the many mathematical models of hydrocyclones that are floating around.  Arterburn's model is one of the simplest, the Plitt model is more complete but also more complicated.  An...
4
REPLIES
648
VIEWS
Started by Peter.Li
Herbst et al. proposed a procedure for ball mill scale-up. It is based on linear relationship between selection function S (1/min) and specific power P/H S= SE×(P/H)  Question 1: "H is the mass of the charge in the mill excluding the media" Doe...
Last replied to by emilyfreire
Peter, to determinate the power in the ball mill or in the rod mill, we can use the Rowland's equation.  The equation is attached. Regards.  
2
REPLIES
390
VIEWS
Started by Chama Kapambwe
Recently put inserts to reduce wear in cyclone inlet but have found re-circulating load increasing as we are now failing to operate on 5 cyclones but 6 due to high pressure. Noticed high pebble generation as well. could that be as a result of high re...
Last replied to by SmartDog
The cut point of the cyclone is also determined by the cyclone dimensions and the feed pressure.  Adding the inserts which caused the increase in pressure also shifted the classification cut point ca...
0
REPLIES
308
VIEWS
Started by jono1028
I have a problem that I'm seeking input.   I have a pressure roller in a paper document reader which runs roughly at 2,000 RPM at bursts of 1000 revolutions per cycle and always a 10 second or more pause between cycles.   My current roller mat...
2
REPLIES
741
VIEWS
Started by Rahul bhoraniya
Is any one have fundamentals of ceramic ball mill? is there any method or material so i can decrease grinding time of CERAMIC BALL MILL? please help me.
Last commented on by Rahul bhoraniya
Its wet type. And material is slurry used for glazed body. Hello please help me to optimise size of grinding mill - Reducing ceramic ball mill design mass of MS
3
REPLIES
624
VIEWS
Started by CHILOBA
Hi I am new in mineral processing industry and I need to know when and how you charge grinding media when ball mill is in operation
Last replied to by David
A friend sent me this: Grinding media management in ball mills Grinding ball additions Grinding balls should be added each shift. Mill performance is negatively impacted when the mill is not drawin...
7
REPLIES
1168
VIEWS
Started by oguzgunes
Hi all, I am wondering about the time of grinding in ball mills. How can I calculate the retention time? Which parameters should be considered? Thanks in advance..
Last commented on by SmartDog
You did not mention the rate you are adding more media. This also should be accounted for. see: https://www.911metallurgist.com/grinding/charging-grinding-media/
2
REPLIES
566
VIEWS
Started by SAKAR
which rubber is excellent for ball mill rubber liners? what should be physical properties and qualities of ball mill rubber liners?
Last replied to by Sandip Trivedi
Nice information to make a best formulation. But SBR and PBR have a poor tear properties compare to NR, PBR has own reliance and abrasion properties good, mill where high tear and cut resistant requir...
3
REPLIES
554
VIEWS
Started by Jaime Jacob
Hello I am begining to study the modelling of the comminutions systems and I would like to have some examples of determinations of the breakage and selection matrix. Anyone have some documents that explain this?   Thank you very much..!!
Last replied to by MillMan
As Alex said, if you love hardship, see this PDF. Its conclusions are that an in depth review of the PBM used to simulate industrial wet grinding has found major flaws in the model showing- There ...
1
REPLY
399
VIEWS
Started by srinu1234
Dear all,  Have a good day! I am trying to determine ball mill work index for a very soft . If I follow bonds procedure to do experiment, not able to determine. The following is the data of ore sample. F80% = 2300mic Mesh of grind =300mic -300mi...
Last replied to by Alex Doll
The objective of the Bond work index tumbling tests is to arrive at a steady-state where the amount of ground material is constant between the stages.  One way to short-circuit the early instability ...
1
REPLY
378
VIEWS
Started by Sayed9
Hi we have replaced the girth gear of a ball mill used for coke grinding, and we have completed gear alignment. our procedure to use four holes of the gear fixing bolt , drill these hole to increase the diameter and then for reaming out . The purpo...
Last commented on by Sayed9
Hi , We are using magantic drilling machine with HSS drilling bit . Have you used Rotabroch for drilling a girth gear ? Annular Cutter will do the job with a good accuracy ?
6
REPLIES
451
VIEWS
Started by Hermann
Hi All, we want to mill a relatively soft galena in limestone ore to prepare it for gravity concentration. Flotation is not possible at the site. The ore is easily liberated, so a grind down to about p80 of 1mm is ok, to feed it to spirals and shak...
Last replied to by Deano
To produce a milled product at around 1mm top size the most efficient way to get the material milled with minimal fines is by using a three stage jaw crushing circuit with 1mm interstage screening bet...
1
REPLY
536
VIEWS
Started by Charlie
Could you recommend a suitable calculation for ball mill charge volume using the chord length of the ball charge? We are currently using the calculation for distance between charge to top of mill. We would like to use the chord length method as well,...
Last replied to by Todd H
https://www.911metallurgist.com/blog/ball-mill-charge-volume-calculation https://www.sagmilling.com/tools_millfilling Might be something here to help your calculations Todd
4
REPLIES
1049
VIEWS
Started by samuel82
Whats your opinion for TPL (turbo pulp lifter) for SAG mill? It seems that by adding a TPL could help increase energy efficiency and reach the SAG mill maximum capacity.    
Last replied to by David
Samuel, here is an excerpt of a paper by https://www.linkedin.com/in/david-royston-02765013/ Modern Semi-Autogenous (SAG) Grinding Mills can be up to 12 metres in diameter (absorbing up to 20 MW of ...
4
REPLIES
1162
VIEWS
Started by FarshidBsr
Hello Dear Friends, We are working in a plant with single stage grinding using three parallel wet three compartment ball mill. Each ball mill operates in a close circuit with Classifier. The fineness of ball mill product is OK so the circulating loa...
Last commented on by FarshidBsr
There are 3 ball mills in our plant so we should differentiate between ball mill power and total power of ball mills which is sum of each ball mills power. By increasing throughput the mill power will...
2
REPLIES
575
VIEWS
Started by Guelb22
Hi All, The shell liner of the SAG mill wear in different rate depend on the position of the liner ring. Do we replace the half shell liner due to only wearing discharge end ring ? how we can manage that to replace the worn ones in time without repl...
Last replied to by David
What you are trying to do is not something I have ever done or seen. We change either the complete shell or half (in a High/Low setup).  We do not change half the DE or FE. You need to review your ...
3
REPLIES
606
VIEWS
Started by hulk
hi,how are you What are the reasons and solution for Sag mill bolt breakage? Tell us about effect of changing liner geometry type of material and metallurgical operation conditions on bolt  breakage. thanks
Last replied to by sslupsky
As mentioned earlier, there could be a number of reasons.  We helped investigate bolt breakage of a rod mill by monitoring bolt tension.  The key finding from that work was minimizing liner movement...
4
REPLIES
669
VIEWS
Started by mokhtaraazami
Hi everybody I work in a iron ore beneficiation plant in Iran. in this plant the feed size is less than 10 mm which first enter to the HPGR (in open circuit) and its product size is less than 6 mm which goes to the open circuit ball mill. my questi...
Last replied to by raghdmuhi
https://youtu.be/Fr9XHChvKIY
3
REPLIES
814
VIEWS
Started by Simba marshy
how can I reduce the the tonnes of rejected by a grate discharge ball mill    
Last replied to by Todd H
Further to above - did the amount of rejects suddenly increase? Ore type change; Feed rate change; Pulp density changes; Feed size change? Has the grind size changed? Is this a new mill with an ungr...
4
REPLIES
730
VIEWS
Started by sajjadaghazadeh
Hello Dear Friends, I hope all of you are doing great. I do have a question related to ball mill liner types.  We are using a ball mill with diameter 3m and length 4.5 m in our plant. The ore is Magnetite with low amount of hematite. Gangue minera...
Last commented on by sajjadaghazadeh
Hi sure; Ball mill 1: 700kw with current working amper 1000 A average. Product size D80:45 micron. Critical Speed 75-80%. Ore work index 12kwh/t. Solid percent 70-80%. Ball mill charge 40 and 60 mm. N...
4
REPLIES
773
VIEWS
Started by Solaris1987
Hello In our iron concentrator plant we use a wet ball mill for grinding of fresh feed. It operates in a close circle with hydrocyclones. The overall data of ball mill and hydrocyclones are following:  Ball mill: F80: 4 mm Diameter: 5.5 m Lengt...
Last replied to by Robert
You might find this approach (see article and webinar) useful.   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>...
2
REPLIES
717
VIEWS
Started by banyechan
what reasons for the increasing ball consumption after converting my overflow mill to grate discharge mill?
Last replied to by Robert
From SME Mineral Processing Handbook, Ed. N. Weiss, SME, 1985, page 3C-28 and surrounding article on grinding: “In grate-discharge mills, due to the lack of pulp in the zone just in front of the gr...
2
REPLIES
830
VIEWS
Started by Hauptsturm
How to increase the density when too much material is reporting to the cyclone underflow? 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...
Last replied to by
I presume we are talking heavy media cyclones here? If so then you should increase the medium density to reject a higher proportion of light minerals to the overflow. But as with everything there is a...
1
REPLY
881
VIEWS
Started by richardh
Hi I am trying to build up a library of papers on the function of a hydrocyclone in a closed ball mill circuit and not as a means 'of doing any grinding'. I am often faced with the question "We have a grind of 'A' micron in our ball mill circuits b...
Last replied to by Robert
Not knowing your situation re accessing technical literature? For some additional details look at: Seitz, R.A. and Kawatra, S.K., Further studies on the use of classifiers for the control of wet gri...

Please join and login to participate and leave a comment.

BUY Laboratory & Small Plant Process Equipment

We have all the laboratory and plant equipment you need to test or build/operate your plant.

ENTER our Mining Equipment' Store

We Sell EQUIPMENT for all types of Mineral Treatment PROCESSES and Laboratory Testing needs

Do you need METALLURGICAL TESTING of your ORE?

View the Services we Provide

911Metallurgist Mineral Processing & Process Development Laboratory

We have a metallurgical test for every possible mineral type and treatment.

Need ENGINEERING Services or Plant TROUBLESHOOTING?

We can IMPROVE ALL PLANTS / Mineral Processing Engineering & LABORATORY Ore Testing

911Metallurgy Engineering

Contact us for process engineering, metallurgical investigations, plant optimization, plant troubleshooting, needs. WE “FIX” METALLURGY.

I Need Consulting Engineering Help
I Need Ore Laboratory Testing