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optimize particle size in sphalerite-galena flotation (3 replies and 2 comments)

6 months ago
hani 6 months ago

hi all

i want to know, what is optimize range of particle size in sphalerite - galena flotation?

thanks alot

Paul Morrow
6 months ago
Paul Morrow 6 months ago

Hani درود و خوش آمد

What is the optimum grind size for good Pb-Zn metallurgy by froth flotation depends your mineralogy and liberation size indicated by it.

I have never seen primary grinds coarser than P80 of 150um nor finer than 50um.

You need to look at your ground samples at 150 um, 100um and 50um if needed and evaluate how much of the galena and sphalerite are liberated from each other and  from gangue minerals.

Another option is to perform rougher flotation tests at varied grinds and see where you get the best results.

6 months ago
David 6 months ago

Thanks Paul and hello Hani,

I'll add to Paul's reply that in a rougher flotation circuit, you are looking to have around 60% of the valuable minerals be liberated.

To get good final metallurgy, you need over ++90% liberation in the cleaner circuit.  Therefore, in sme cases, you will need regrinding your Pb and Zn rougher concentrates.

The definition of liberated minerals varies by metallurgist and laboratory. Here is a common one:

If you have little money/resources, have a review of https://www.911metallurgist.com/blog/size-microscopy-optical-mineralogy

6 months ago

I have been getting a lot of this kind of stuff coming up along with tiny gold flakes and nuggets about the size of a grain of sand. This stuff is really hard to seperate from the precious metals. I knew it was some kind of mineral but couldn't figure it out. Its kind of a pain in the neck to deal with.

6 months ago

Hi D,
what stuff and where? Photos?

6 months ago
Dynamo21 6 months ago
1 like by David

I don't know too much about galena, I have found some good samples of the stuff that contained much silver. But I have not tried to work any of them. I have been working a river containing much zirconium I know that because I have held a blacklight to the river sand and it blows orange under a blacklight indicating zirconium. I knew a physicist who used I think it was either soap or detergent to foam up the lead from galena with an eggbeater. I don;t know if the silver came up with the lead. The lead came up with the foam and he just dried it out. It was so long ago I just can't remember remember what kind of detergent. I think it was dawn.

I have not gone into the Colorado mountains for a few years now. This was a few years back. I'm trying to get back up there. We are located in the Denver area. I put all the float material in the crucible and melted it. Only got one quarter of a gram of gold from six grams of float material something might have messed up the process. I don't usually take pictures but I could probably get some pics to you next time I work the river.


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