Grinding & Classification Circuits

Grinding & Classification Circuits

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Effect of Liner Type on the Ball mill Product size (4 replies and 3 comments)

s
sajjadaghazadeh
6 years ago
sajjadaghazadeh 6 years ago

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 mineral are mostly clacite, silicates and clays minerals too. 

The fact is that we are producing -45 micron magnetite concentrate in 2 series ball mills and both liners are Equal Height Liners. I think this type of liner could not fit secondary ball mill because friction in this type of liners is low. Can someone help me about the best optimum used liners in the secondary ball mill, specially in our plant.

I would appreciate your time and attentions.

My Best Regards

b
Robert
6 years ago
Robert 6 years ago
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Would you provide some additional details about this circuit:

  • First and Second Mills: Is first mill open or closed circuit, reverse or forward? Is second mill closed circuit, reverse or forward? 
  • First Mill: What is F80 and P80?
  • Second Mill: What is P80?
  • Is your reference to wave liners or are their equal height lifters? 
s
sajjadaghazadeh
6 years ago

He dear Robert;
We use first ball mill with D*L 3.2*4m.
First Ball mill is open circuit. (Hydrocyclone is existing but not in the circuit right now).
Second ball mill is also the same dimension as for first ball mill. Second ball mill works with 12 hydrocodones of 150mm in diameter.
Plant feed is about 65 t/h right now.
P80 is 50 micron right now but the nominal capacity of the plant should be about 75 t/h.
The plant feed D80 is about 6 mm and both ball mills have liner types of Equal Height lifters.
I am thinking that is the second ball mill liner type is correct because we are going to produce -45 micron but this type of liner mainly impose breakage (collision) effect on the particles rather abrasion

F
Otlanto40
6 years ago
Otlanto40 6 years ago
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Dear sajjadaghazadeh,

I can help you with your questions, but I think is necessary that I can know FlowSheet from you Plant.

I remain attentive to your comments.

Sincerely,

FR

s
sajjadaghazadeh
6 years ago

Dear Friend;
Thanks for your reply. Unfortunately right now I dont have access to the plant PFD but I think I have described the process here. If it is not enough Please let me know
Best Regards

s
sajjadaghazadeh
6 years ago
sajjadaghazadeh 6 years ago
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Can Someone help with this issue?

b
Robert
6 years ago
Robert 6 years ago
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Can you advise about the following:

  • size grinding media (balls) in both mills?
  • are the mills drawing available power? Along with this, what is installed power? 
  • circulating load and cyclone efficiency for second circuit?
  • transfer size from Mill 1 to Mill 2?
  • % critical speed for both mills
  • Bond Work Index for the ore?
  • what % solids in each mill?

 

 

s
sajjadaghazadeh
6 years ago

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. No hydrocyclone with first ball mill i.e. open circuit

Second Ball mill: 700kw with current working amper 950 A average. Product size D80:180 micron. Critical Speed 75-80%. Ore work index 13kwh/t. Solid percent 70-80%. Ball mill charge 25mm. hydrocyclone with first ball mill with circulating load 350%. Hydrocyclone diameters 150mm with pressure 1bar to 1.5 bar.
Total plant feed 65 t/h

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