Crushing, Screening & Conveying

Crushing, Screening & Conveying2017-04-04T06:57:13-04:00
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Hammermilling Mohs hardness 5 & 6 (6 replies and 3 comments)

Kedougou gold
2 years ago
Kedougou gold 2 years ago

Hello All 

Have a newbie question. 

we have a geology for a new site and the ore we need for final hammermill 

The mineralogical study carried out on this ore allowed us to make the following observations:

Gold ore is macro-grained, whitish, greyish or ocher in nature;

It is composed mainly of quartz, plagioclase, chlorite, pyrites, oxides, iron hydroxides, carbonates and gold;

The crushing and spraying of the quartz ore is done without any significant constraint: although the quartz is generally hard and abrasive, the development of cracking systems (microtectonics) in the ore considerably reduces grinding efforts.

Now my question is from the cone crusher we will have 10mm to put through our hammermill to reduce to +40 mesh (0.420mm or below). (15 to 20tph)

Because the quartz is 7 on mohs scale can we still use a hammermill that is normally spec,d to do mohs5 max 6 ? 

I understand the hammermills will wear out quicker but will it still do the job if we recirculate oversize. 

This will just be a temporary measure as we have the correct machine on order but lead time is 3 months. availability on correct machines are scarce in the region but can source hammermill that is 5 mohs scale told it can do 6 max. 

Thanks for any help 



Image result

2 years ago
Vortex 2 years ago

If you are in Australia we are about to run a new 20tph vortex plant, we are looking for wide range of test materials, Melbourne site, require about 500kg minimum for individual tests, no cost.

Our vortex uses high pressure air and acoustic pressure to reduce ore to a very fine powder. In your case if the feed is at 10mm we will get that down to under 80 micron immediately and far lower if we pass it twice.

We are establishing wear rates on quartz an similar ores from December 2017.

The test programme will run through BOF slag, any ores, and coal. the supplementary programme will cover almost any material from wheat to limestone.

Kedougou gold
2 years ago


2 years ago
Robert 2 years ago

You will likely be performing much more maintenance with the hammermill. Observe the high wear areas and it may be possible to make modifications to improve wear resistance.

What is the 'correct' machine you have coming in the longer time?

Kedougou gold
2 years ago

Hi robert thanks for taking the time to respond
The equipment is from america a dreamcrusher and another made to measure.
So basically it will crush but more wear and tear
AS said its just a stop gap for 3 months

Master Q
2 years ago

Excuse my ignorance but what is a "Dream Crusher" ?
A brand I assume but I cant find anything on them?

2 years ago
David 2 years ago

Here Master Q Big and Little DREAM CRUSHER

Use the Social Share Bar on the Left. Tell everyone you can about It's FREE & GOOD.

2 years ago
Deano 2 years ago

I am very interested in your vortex plant, any chance of getting some detailed information on how it works, plant sizes, results so far, costs and availability.



2 years ago
Robert 2 years ago

I don't know about the liners that come with the referenced 'dream' machines. However, it may be possible to improve wear life by following some of the principles used with VSI crushers & creation of dead particle beds through liner design. This autogenous bed may protect at least parts of the crusher internals. 

2 years ago
JJA 2 years ago

Hello Kevin,

I would see if it's possible to upgrade the wear parts to something more robust. AR400 or AR500 steel for liners, rotors, and screens, and maybe a chrome alloy for the hammers. Based on the Mohs rating I would think the mill would work okay, but that the wear parts would be worn out prematurely. I've seen standard steel or manganese steel hammers last about 30-50% of the life of chrome hammers with quartz ore, for example. I would be curious to learn more about what they're using on the inside of the mill. It might be worth the increased cost to upgrade if it means it pays for itself in extended life of the wear parts. 


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