Laboratory Testing & General Mineral Processing Engineering

Laboratory Testing & General Mineral Processing Engineering 2017-04-04T06:57:51+00:00
  • To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Mineral Processing or Laboratory Work.
  • 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.

Sources of head grade variation-difference (7 replies)

Alan Carter
2 years ago
Alan Carter 2 years ago

What could be the cause of getting different Head grades from two plants which receives the same Ore type from the same mine? The feed to the plants is only split by time or silo availability.The two plants uses FAG mills in close circuit with a classification screen. The one plant is consistently showing higher feed grades to the primary rougher float than the other. What affect the grade output from a mill?

Dizzy Flores
2 years ago
Dizzy Flores 2 years ago

1. Are there differences in sampling to determine ore grade between the two plants, i.e. is this a quality of measurement issue?

2. Is feed for the two plants pulled from different locations in a common silo/stockpile?

Carmen Ibanz
2 years ago
Carmen Ibanz 2 years ago

1. There is basically no difference in sampling since the samples are not taken manually unless the maybe the preparation which could be different however the consistence seems to be suggesting something else.

2. The feed is pulled from the same stockpile and the same bunker locations from the same mining shafts.

Although it will be difficult to determine if it is quality issue/people, other factors cannot be ruled out as well.

Helena Russell
2 years ago
Helena Russell 2 years ago

Perhaps there is a segregation issue in the stockpile? Is there a noticeable difference in feed size distribution to each train? Is there a grade-by-size relationship?

John Koenig
2 years ago
John Koenig 2 years ago

Some questions:

- Do you look at the difference daily?
- If you plot the difference Stockpile A - Stockpile B; is the difference sometimes positive and sometimes negative OR is it always positive or negative?
- What is size of difference as % of the average metal content?

Need some data to comment on your problem!

Jean Rasczak
2 years ago
Jean Rasczak 2 years ago

I would start by asking how different are they? Marginal or big difference? If its marginal its normal but if the difference is huge it might be one of the following

* haulage is split by time, it’s possible to receive Ore from different stopping areas which suffered different dilution factors

* analysis is done by separate labs for each plant, it’s possible that the equipment in use maybe different in accuracy or the skills of analyst.

Marshal Dienes
2 years ago
Marshal Dienes 2 years ago

We are having segregation issues I guess that is the main factor leading to the difference - there is consistently more coarse material going to the other plant than the other.The difference is similar throughout and positive.

Bill Fraser
2 years ago
Bill Fraser 2 years ago

Of course segregation in stockpile will cause the difference. The line with coarser feed size has less head grade and vice versa. But of course it depends on mineralogy of deposit. It refers to porphyry copper deposits.

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

Have a Mineral Processing QUESTION?

Come in, ask your question

911Metallurgist Community Forums

Talk to other metallurgists and be helped.


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.

Checkout our Mining Process & Lab Equipment SelectionCLICK HERE TO ENTER
+ +

Pin It on Pinterest

Share This