Pyrometallurgy: Roasting, Smelting, Refining & Electrowinning

Pyrometallurgy: Roasting, Smelting, Refining & Electrowinning2017-04-21T02:33:06-04:00
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Started by Rahil Khan
I want to know if it is possible to extract the gold in ashes fine carbons. Smelting is the method I know could be used but i want to know if anyone has another recoverable method. Remember, it’s an ashed fine carbon we are trying to extract. Inten...
Last commented on by rob riggir
Hi Mishaka - during ashing of loaded activated carbon you will drive off cyanogen and oxidise any non noble elements. During direct smelting of the ash you will disassociate the aurocyanide into more ...
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Started by Roselyn Yeboah
Please can someone help me with ways to ash gold activated carbon followed by smelting! . I tried ashing 300g using a pot on a gas cooker but we couldn't get the carbon to burn so we tried smelting the granule with borax and salt peter as flux. The s...
Last commented on by Roselyn Yeboah
Thanks
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Started by Reidy
Hi, has anybody melted gold concentrate and poured it without using any flux's? Our goal isn't to refine the gold as the mint does that anyway and the cost will be the same. We have low iron and lead levels and I was just curious of anybody having ...
Last commented on by Joeram
Auexplorer. I am trying to find out best way for me. I have gold with alot of pyrite/sulfides. I want to get the gold from the pyrite/sulfides? Was told crush fine 400 mesh, roast with charcoal and sa...
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Started by Sachin Prakash
I am looking at a quick and cost effective method to recover the gold in the fine carbon ashes we have. Currently we are trying to use smelting but we want to try some other means of getting the gold. Can I try Mercury in amalgamation and also gravit...
Last replied to by Keisyakeith03
The best think is use litharge as a flux for ash smelting.
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Started by Ahmed Zaky
Hello  i want to ask  about the efficiency of gold recovery from ash of activated carbon by aqua regia (active carbon loaded with gold from cyanide leaching )  where this ash contains average gold 15 gram per kilo ash   thank you
Last commented on by giom
mr ahmed please do you have any idea how to refine microscopic gold .iuse aqua regia on gold ore and i do precipate with smb a orange brown gold powder but no way i can melt it it fuse to black slage ...
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Started by Oberstorm
Is there any disadvantage in using nitric acid for acid washing activated carbon? I am currently using hydrochloric acid, between 3 and 6%.
Last commented on by hulk
what is the disadvantage of sulfuric acid for carbon wash?or heat exchanger plates wash.,?
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Started by Japhet
Hi Team, I getting trouble to improve fineness on Dore' as most of the time i am getting more  50%+ Ag, Is there a specific flux recipe or extra additive that has been tested to improve the fineness of the gold bars? 
Last commented on by .999
The process David is referring to is called " inquarting " or " quartering." It's when refiners lower the percentage of gold to 25% by the addition of silver or a base metal such as copper. 3 parts si...
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636
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Started by CA
We've been successfully running a small scale alcohol (isopropyl) zadra stripping process for a while now.   We've begun a carbon stripping service for clients and today ran into something we have never seen.  During the electrowinning process, a...
Last replied to by Jorge
I think the leaching agent is responsible to form the black deposit on the anodes. The oxidants and electrowinning process can form a black deposit on the stainless steel. There are several secret re...
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Started by EcoBlu
In an RDO induction furnace, we are trying a new flux recommended by a friend who is supposedly having success with it.  The ingredients are: 1# Silica, 1# Lime, 1# Soda Ash, 1# Anhydrous Borax, 400g Baking Soda, 4 teaspoons Potassium Nitrate, and 4...
Last replied to by
The recipe sounds like baking cookies, pretty bizarre. Too many elements competing with each other. The flux would be suited to reducing an impure iron ore, not much else. Boiling over is likely caus...
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Started by Mikhail
I need a method of burning carbon and smelting to extract the gold. Can anyone suggest a method? What are the potential losses of metal can be?
Last replied to by Mikhail
Hello dear colleagues, thank you for the comments to my question.I'm working on a project to extract gold from the dumps of amalgamation. The technology of heap leaching. Gold-bearing solutions are fe...
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Started by Amir
  I recycle metal (gold. Silver and palladium) from pcb by hydrometallurgy process. Before i dismantled component  from pcb with  air hummer. But now i decided chemically by  organic solution  like  alkane sulfonic acid and glycol ether  sel...
Last replied to by David
Amir, this may help (not perfectly) ...but have a read to https://www.911metallurgist.com/blog/electrolytic-method-recovery-lead-scrap-batteries page 14 talks on Tin separation of Lead. Fortunately,...
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Started by Colin
Can someone explain the process of extracting gold once you have obtained a concentrate after putting your alluvial material through a gravity machine. We put about 200kg of soil through a gravity machine and ended up with about 2kg of concentrate. W...
Last replied to by Jorge
You do not mention the gold recovery. It is important to calculate it to evaluate the metallurgical performance of the gravity circuit. I think you should clean your gravity concentrate using a shaki...
2
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703
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Started by ameer
Hi, I faced problem in  our pressurise  zadra cell. High voltage appeared 12 volt during gold stripping, ampere was set to 660A, flow rate is 11.5  Temperature is 150 C, anyone can help me to solve this problem
Last replied to by Wayne
Hi,  i would check all your connections in the system, at first glance it sounds like an electrical problem like a partial short causing current to spike, not sure why your voltage would go up though
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Started by sarchery
Is there a specific flux recipe or extra additive that has been tested to improve the fineness of the gold bars that contain high copper content during smelting. The current flux constituents are borax, silica and potassium nitrate
Last replied to by David
Try adding 5% feldspar.
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Started by Charlie
I am having a problem of gold not coming off from the steel knitted mesh in the cathodes in the electro-winning cell. I tried putting the steel knitted mesh in nitric acid before washing it off with a high pressure wap machine but still doesn't co...
Last commented on by Subhash-Kumar-Roy
very inexpensive steel wool=mild steel
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Started by goldinvestor
Hi, I have been invited to invest in a new gold mine (in Scotland) which has just announced preliminary results from a tailings bulk processing trial and I'm trying to get a rough idea of revenues. The Au grade of the tailings is 8g/t (the mine when ...
Last replied to by max skinner
My suggestion, you need a 34 or 64 element ICP to see what is in the concentrates so you know where you stand. The lead concentrates will be the most difficult to get rid of, there are smelters in Mex...
2
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1278
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Started by Madungo
Hello, I need help to releasing gold lock up from my CIL circuit's carbon. I want to run more frequent elution in order to get more gold out but we seem to only recover what we're putting in only. My gold locks up in the tanks and it increases each...
Last replied to by Cyanide
Madungo, Good practice to do monthly gold inventory so you can track circuit inventory and establish good optimum. Most of it is carbon related. Gold on slurry normally only in circuit for 24 hours b...
4
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Started by Panashe
My Company is involved in toll elution using the pressurized Zadra (350-400kg carbon load), we are now considering using an AARL elution for toll carbon desorption as an upgrade from the pressurized Zadra and the Peter Goossen plants are there any po...
Last replied to by ThabisoKwenane
For water treatment, you can use cat-ionic resins in columns to soften your water. Use brine (NaCL solution) for flushing into your water softener plant. The ultimatum goal is to reduce as much calciu...
7
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Started by Rahil Khan
AARL Method of Elution is used for gold recovery at our Plant. I really want to run an optimisation test on our elution circuit and i wish I could get some help with papers concerning elution Optimisation and what will cause high barren carbon assays...
Last commented on by Panashe
is there a possible way to in touch with you on general manuals for AARL process
3
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Started by Helena Russell
Some friends are operating a small carbon elution plant. Their gold electrowinning processes 300kg of carbon per month. They have low-pressure boilers and usually leave the carbons in for 48 hours per elute. They test the pH strength every morning...
Last replied to by ameer
What  about over voltage  12 volt  
1
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Started by Omurvama
Hi all! I want to smelt an ore with 4 kg/Ton of silver. I have been reading about the process and there are several kind of fluxes can be used. What could you tell me about it? is enough the silver in ore to think in smelting? is the flux selection ...
Last replied to by grant.k.harding
Dear Omar,  The ore has silver worth about $2,500 per ton, so its not worth direct smelting at that concentration, unless you already have the facilities to smelt it. If that’s the case I would ne...
2
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Started by girishchandra
I want to know about electrorefining of gold to get  higher purity of gold metal. Input of gold would be up to 98% or above . Please help me.
Last replied to by girishchandra
  I am trying to achieve purity of gold about 99.99% Using chlorauric acid for electrorefining.
6
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Started by applelab
i read that borax (flux) reduce the melting temperature of gold during smelting. How is this so? Thanx.
Last replied to by dhaefi
how we can we determine the concentrate of borax that is use to burning gold ore
1
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666
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Started by CA
We are using the alcohol Zadra method to treat our carbon.  However, due to the origin of the ore we are treating, we wind up with leaves, roots, etc. that catch on the carbon screen i.e. Trash in elution column.  Separating these plant products f...
Last replied to by
I think you should screen it out from the grinding circuit cyclone overflow. It really is not that hard/complicated. It might cost you $200 to build a trash screen with 1 cm holes in it. https://www....
3
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Started by kahonde
hello, how does carbon get contaminated with manganese and iron during electrowinning using a single boiler?  
Last replied to by David
It is in your question. You don't know what it is?
5
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Started by kannan
I wonder how to increase the panning of gold containing borax slag? Is the particle size affect the panning yield?  
Last replied to by kannan
Which flux is more oxidizing potassium nitrate or sodium peroxide? for smelting with borax.
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Started by kannan
We are currently trying to remove only iron,zinc and indium in the alloy gold in the melting stage itself , other than copper and silver with gold. The reason for this trials is direct usage of the resulted alloy gold to the further process by adding...
Last replied to by Marshal Meru
The metals slag out in the following order, as oxides: zinc, iron, antimony, arsenic, lead, bismuth, nickel, tellurium, copper. In doesn't mention indium, but I would guess it would oxidize, too. Ther...
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Started by Sturmbann
We do acid washing on our carbons and regeneration as well, but our current barren carbon loading is very high compared to the previous loadings. This is a major worry now since our protocols are still being followed as before. I want to know, in the...
Last replied to by jculver
I have found in a zadra strip process the fouling of carbon by silicates due to the very high pH used (11.5-12.2). Acid washing of the carbon showed no benefit, we ended up feeding the fouled carbon t...
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Started by CA
We are using the atmospheric Zadra process with 10g/L NaOH  and 1-2g NaCN/Lat about 90 deg. C. to strip our carbon.  We do not have access to electrowinning cells or a traditional Merrill Crowe circuit, so we are passing the heated eluate over zinc...
Last commented on by CA
Thanks for the great information; I never considered the micro-pockets of low pH. I will let you know how we make out over the next week. It doesn't sound like zinc precipitation is something we ar...
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Started by Kumar Choudhry
The practice of discharging waste acid after acid was in elution into leach tanks as a form of disposal is being practiced. Is this a normal practice or it has severe impacts on the leaching kinetics as well as the leaching parameters. Please educate...
Last replied to by Kumar Choudhry
Wonderful suggestions and advice here! Thanks to you all for your invaluable contributions. I now know what might and what is happening once we discharge the waste acid into the leach tanks. Especiall...
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Started by Obergruppenfuhrer
What happens if I boil pregnant carbon in aqua regia? Does it remove the adsorbed gold into solution? If so, can I bring the carbon loading to below 2gpt insuch a process?
Last replied to by Tarun Karakoti
Continuing with the discussion as it appears to have generated some interest: In acidic solutions such as loaded C in AR, the CN complex will precipitate out as AuCN solids with liberation of HCN gas ...
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Started by
What are the effects of Calcium on elution?
Last replied to by Paul Morrow
Basically Ca ions form into scales at high temp during elution process that blocks the heat exchanger and other pipes, during reagent circulation.It has less effect on the kinetics of the reaction.
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Started by
I am chemist and I want to recover silver from jewelry rubbish by electrowinning. Does somebody have some information or book where I can find detailed information about it?
Last replied to by Obergruppenfuhrer
If you read the method I wrote above: Silver chloride and caustic soda turn silver into oxide and the glucose reduce it into silver metal. That method even can also bypass the silver chloride process....
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Started by Maya Rothman
Are there any definite solutions for passing/leaking Pump Cell Circuit valves/gates? It has becoming a constant reappearance of losing gold to solution tails due to these faulty valves for us. It is such a labour intensive work for operators to seal ...
Last replied to by Maya Rothman
Yes I have just read that report recently. There will still be a lot of work to do to get these valves sealed properly!
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Started by Helena Russell
Is it possible to do the carbon elution using a solution contains only caustic soda and no cyanide? If it is possible and known, is there any name of this process?
Last replied to by Sturmbann
It is possible. We had tested for three strips. The barren carbon grades were less than 100ppm.

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