Best method for used crucibles PM recovery?

[nickvc]

Deano my thoughts were towards cheapness and the fact this will not be an ongoing process once done the job is finished until the OP collects enough crucibles to make it worthwhile to run again so I was trying to find cheap and easy ways for him to process his material without spending large amounts of money.

If you are going to mill and separate the concentrates down to metallic prills then it makes more sense to use acids, it's quicker and more efficient as it will dissolve everything regardless of size which cyanide will struggle to do.

 

[kurtak]

Deano just a thought would adding soap to the water and simply keep a running stream going into one container and onto another one remove a lot of the light valueless material before trying to do a better separation with the table, I'm thinking the less junk to start the easier to recover the values, I'm thinking the water would need to disturb the material, make the water cloudy and then be poured into another container and so on.
This is not my area of expertise as you well know just trying to think of ways to make life easier cheaply.

Nick

I am not sure how well that would work for crucibles milled to a fine powder (as milled crucible powder would be heavier then prolized/incinerated IC chip ash/carbon) but it works very well for IC chip ash/carbon

I have a 5 gallon bucket set up just for this purpose - its very simple to make (as shown in the pic) its just a matter of cutting a piece of the bucket lid out & putting it back on the bucket to create a lip on the bucket

The lip on the bucket allows you to make a faster & more complete pour off of the water as it holds back the heaver material

using this bucket to "pre" concentrate my IC chip ash/carbon reduces the amount of material I then take to my concentrator table in about half - AND - cuts my total time concentrating in at "least" half if not more then half

Like I said - I am not sure how well this would work on "fine" milled crucible material - so I don't want to hi jack this thread with details - so will try to post a new detailed thread on the process in a couple days (as I am going to be busy with some smelting for the next couple days)

Kurt

 

[nickvc]

Kurt I think that you would need a heavier flow than with ash but I have never followed this procedure so I'm just thinking out loud, if my thinking is wrong then I'm happy to have it pointed out, I know Deano is the expert with mining materials so if he says it's a no no then that's good enough for me, like you Kurt I was hoping to reduce the time needed on the table which needs watching whereas the set up I had in mind could be set up and left to its own devices to a large extent.

 

[autumnwillow]

Of course with Deano's table in mind you wouldn't have to separate the ash. With a common sluice box that will really take up a lot of time.

 

[kurtak]

autumnwillow

Correct - with the shaker table there is no need to do the bucket "pre concentrate" as it is so much more efficient then a sluice box/miller table (when it comes to IC chip ash/carbon)

What size is your shaker table ? --- one of these days I want to get the 2' X 4' table - just haven't "quite" been able to justify it yet

Kurt

 

[autumnwillow]

How I wish I already have one, can't even find a local supplier yet. I think I may need to import.

Edit to add: Come to think of it, why not build one? Only the grooves seem to be the hardest part of it. Not sure what they are made of, the rest is just a pump, 2 catch basins, a vibratory motor, etc.

 

[Deano]

Yes I was referring to the Wilfley type table.

They are available quite cheaply from China but the tops have top be replaced before using, they are very crudely made.

Do not get one as shown in the photo with a bend in the top side half way along.

This form is almost impossible to run for a clean concentrate line, at the discharge end there is no room for either a dedicated concentrate discharge or a splitter, you need both.

The spray bars as fitted are good but a feed box needs to be fitted in the top right hand corner.

A water supply is fed into this feed box and the spray bar is correspondingly shortened.

This ensures that the feed is fully wetted before it is subjected to the table action.

Read my post on Oct 10 in this thread for why you do not want to leach the pulverised material.

The prills are resistant to strong oxidising leaches (aqua regia) as well as cyanide.

Deano

 

[nickvc]

Autumnwillow am I correct in thinking that most of the crucibles are from jewellery manufacturing rather than refining and recovery, the reason I'm asking relates to Deanos worries about the prills and residues been resistant to leaching, in my mind if the values are basically carat alloys you should be able to leach or fully dissolve the resultant material with AR, dependant on whether you work with large amounts of silver a nitric digest first may pay dividends also whether you use the crucibles for only gold or silver, if this is the case then melting the residues with more silver or copper and cornflaking before leaching with nitric would be advisable.
If the material is all from recovery and refining them follow Deanos advice to the word.

 

[autumnwillow]

Autumnwillow am I correct in thinking that most of the crucibles are from jewellery manufacturing rather than refining and recovery, the reason I'm asking relates to Deanos worries about the prills and residues been resistant to leaching, in my mind if the values are basically carat alloys you should be able to leach or fully dissolve the resultant material with AR, dependant on whether you work with large amounts of silver a nitric digest first may pay dividends also whether you use the crucibles for only gold or silver, if this is the case then melting the residues with more silver or copper and cornflaking before leaching with nitric would be advisable.
If the material is all from recovery and refining them follow Deanos advice to the word.

A mixture of both actually.
I would use silver as a collector after recovery to smelt. Assay, inquart, nitric digest then AR.

You aren't referring to the whole crucible being digested in AR right? What you are referring to is the recovered material after milling and using a concentrator table?

With what Deano said, crucible prills/slag whether milled or not will not be properly leached in AR and/or cyanide due to contamination of base metals.
While most ores are usually high karat gold, they should work fine in a cyanide/AR leach.

 

[nickvc]

In this case with mixed material I would follow Deanos suggestions, his knowledge on this sort of material is far greater than mine.