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Started by ramine
hello i working in Crud Recovery in copper SX (solvent extraction) i separate the organic phase by bentonite clay then organic phase separated from crud ... i can load this organic to system ?
Last replied to by Farhad Baghery
Hi Kevin, Could you please explain your calculation? how many clays for how much organic?
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Started by Irene Ibz
Hello, apart from arranging regular screen maintenance, how can I check for interstage screen leakage manually during the shift?
Last commented on by mashudu
no carbon is suppose to be visible when you do the check on the discharge sample, if any carbon is visible it will mean : 1. if its finer than the screen appeture it will mean you are creating fines i...
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Started by Rob.Earth.20
Can I make a Copper Sulfate solution with this unknown copper ore and sulfuric acid without using a burner or roasting? How?  Can I just using a crushing and just directly dissolving the copper using the sulfuric acid? Thanks
Last commented on by inOr
Rob. I don't know the answer to this question. The only chromium ore I know of is chromite, Fe Cr2 04. The chromium in chromite is trivalent (in the +3 oxidation state.) and not terribly toxic. Ho...
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Started by Wadzanayi
I would like to know how I can modify the cyanidation process to leach a gold ore which has got the following characteristics:  Au grade 3-4 g/t   Hg grade  1-2.5 g/t  Cu, As,Sb grades: trace FeS: trace The ore has produced unsatisfactory r...
Last replied to by Auexplorer
I am curious, Please excuse my question, Why the amalgamation circuit when grinding to 75 micron, seems like an extra circuit. Any free_mill material would be caught in the grinding and classification...
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Started by Colin
We are in the process of building a VAT Leaching plant and I have just received the 32 element test from SGS with a breakdown of the elements. The As and S content look a little high so I was wondering if I need to pre treat the tailings before loadi...
Last replied to by David
Colin, the 0.7% Arsenic you have may be enough of a leachability roadblock but it does not confirm it 'the problem'. The Influence of Arsenic in the Cyanidation of Gold Ores is explained by W. B. B...
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Started by Parmanand
I want to recover gold and iridium from element with below combination. CU - 63% Ir - 17.61% Ag - 16.20% Au - 3.04% Nickel - 0.13% Mercury (Hg) - 0.002%
Last commented on by inOr
From what I read, it looks like the cyanide waste is deliberately acidified to drive off HCN gas. Like they say, do not try this at home. I can see why doing so safely requires a substantial investm...
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Started by Ozgun
    In HPAL (High Pressure Acid Leaching) of nickel, pressure leaching is used to be done in pachuka tanks but it has become obsolete and instead of pachuka tanks, titanium lined autoclaves are being used. From a technical point of view how can tit...
Last replied to by Rheomet
If you are referring to laterite Ni-Co leaching, HPAL is a well established process (Moa Bay, Murrin Murrin, Coral Bay, Ambatovy, etc.). It is essentially an acid digestion, but recovery is increased ...
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Started by vekian
I have years of hands-on experience on various CIL/CIP plants but the one I am currently at have an almost manual process of when a carbon pull has finished from the 1st carbon tank (usually about midnight), to straight away transfer carbon from the ...
Last replied to by Jorge Ganoza
I think the first tank collects more gold because it receives fresh slurry from the grinding or leaching circuit. In one operation, when we started up the operation, carbon was added in the first tank...
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Started by Irene Ibz
hello, In our plant there are carbon which were dumped back then, they are known as reject carbon. These reject carbon consist of grits. In order to save the cost we have decided to reuse these carbon in which their activity is about 12% and they ha...
Last replied to by Vault Dweller
Another option for separation could be; if you already have a Gemini or Wilfley table set up, or access to one, you could possibly split the carbon out. Or if you could rig an old cyclone up with the...
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Started by Irene Ibz
hello, I have been given a project on carbon inventory and carbon activity improvement. Currently in our plant we are getting a huge change in carbon inventory in CIL circuit during opening and closing stock. Also the activity of carbon is lowering....
Last commented on by Irene Ibz
Thank you so much wayne, but i also wanted to know how to minimize these losses on carbon. The history is that the open stock as per September 2016 was 100t, added carbon was 15t therefore required c...
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152
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Started by Jaime Jacob
Hi my name is Jaime I'm trying to Learn modelling. I would like to model the moving the solution leach in heap leaching and may be the metal extraction. I have seen many of this studies of modelling in differente journals but only show some equatio...
Last commented on by David
READ https://www.911metallurgist.com/blog/heap-leaching and its +200 pages of PDF. 
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Started by kahonde
hie, can caustic soda at pH 12 affect carbon adsorption of gold ?
Last commented on by kahonde
we sometimes reach pHs of around 12,let me read the pdfs thank you.
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169
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Started by kahonde
hello i'm using vat leaching but im having a problem with the carbon absorptivity, usually we would get 1 kg recovery but these days we are only achieving atleast 500g. i have tried to use surf in hope to get some improvement, i'm yet to check the r...
Last commented on by Wadzanayi
Surf (soap) contains sulfonic acid which is a an organic carbon foulant thus lowering carbon activity or absorptivity. The only best way to overcome organic fouling is to regenerate the carbon so t...
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Started by Dan88
Good day, I am trying to figure out the optimal flow rate for a large tank. I am used to 30 ton VAT tanks but have since started using a 150 ton VAT tank. I know that with a 30 ton tank the flow rate is around 5 l/min but if i use the same flow rat...
Last replied to by kahonde
0.1% is the ideal but if you leaching high grade ores you might need to use 0.18-0.2%  
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Started by Louise
I just want to ask on how to calculate the harvest time of carbon in cyanide leaching. Its the time that the carbon will reach 1500 grams/tonne? The carbon loading is linear. Thank you for answering 🙂
Last replied to by Wayne
Hello Louise, I am not sure how you are set up, however in our Demonstration plant we had 7 carbon columns arranged in successive order where one would take the overflow from the previous and so on....
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Started by Biglizer
Hello everyone Is vat leaching the best method to extract high grade gold with coarser particle, if not why? What is the best method of extraction besides mercury amalgamation Thanks 
Last replied to by max skinner
You will need to get the course gold out first, like anything larger than about 100 mesh. Course gold just doe's not leach well, very slow. As ace says above you can use Knelson or Falcon concentrator...
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201
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Started by Adelnini
Clay from ROM is 10%, and it contains 0.05% copper.. What should we do to clay before feeding to SABC? Can we still recover Cu from clay?
Last replied to by Sugar Watkins
0.05% copper = What does it matter THAT IS NOT ORE. On an industrial scale, clay is there to stay. 10% is bad news. What are you doing: Leaching gold or floating copper/copper-gold? Can you clarify......
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Started by kenyaAurefiner
USING ACTIVATED CARBON: Hello there... Could someone help me with info about using activated carbon in heap leaching method. We have acquired goldix 570 and realized the recommended method by using activated carbon. Considering we have never used it ...
Last replied to by Cyanide
Hello Adam, you handle Goldix just the same as if it were cyanide; from carbon loading to stripping.
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Started by Handerson
Gold Dressing Agent (GDA) product that has Chinese origin, meets environmental requirements and reduces the leaching time and energy costs and effluent treatment.Do you know any application on a large scale? I'm the product for testing, I know some s...
Last commented on by McDeejs
your emai please
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271
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Started by Mikhail
Dear colleagues Does anyone have any information on possible leaching of water amino acid solutions of gold, of peptides, proteins, nucleic acids
Last commented on by Mikhail
Thank you very much, I will be very grateful pinyasov.estageo@mail.ru
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Started by nurdyme
A mine is planning on increasing the leaching density from 40% solids to around 50% solids, with the aim of increasing the dissolution rates, although right now they are working at recoveries of 85%. what would be the effect on the kinetics of diss...
Last replied to by nurdyme
FINISHED LAST WEEK  Leach test at different densities Methodology  Bulk samples of thickener underflow was used for the test work  All samples were done in triplicate  Pulp was made up...
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170
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Started by ChemEngStudent
It will be much appreciated if i can get good articles or information about bioleaching of gold and how it differs from more traditional methods.     Thanks
Last replied to by John Koenig
Gold extractability was measured by cyanide leaching in the same manner before and after biooxidation. Small samples of ground ore from shake flask experiments were leached by slurrying samples of t...
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Started by firebird
Hi everyone. I am now engaged in a CIL circuit. I tried to calculate my final gold bullion recovery after smelting but I cant. The problem is I had a total of 76kg gold fed to the grinding for 11 days.in the final circuit of the CIL a total of 4kg of...
Last replied to by Greg Henderson
Reconciling feed gold with back-calculated gold based on change in inventory + dore gold + tails gold can be tricky as sampling of feed in a representatives manner is notoriously difficult, especiall...
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Started by New Era
Is there any test procedures to know the physical strength and adsorption ability of activated carbon for CIL application.
Last commented on by David
Wonderful Procedure & Method for Activated Carbon Testing Mr. Bhaduri. Thank you for this.
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Started by biteyaboy
Is there any method to check either sodium cyanide is expired or still OK? If yes what is the procedures?
Last replied to by ThabisoKwenane
Good day. Well I don't think NaCN would expire. The procedures stated on how to test the CN- or NaCN are on point. Free cyanide can react to form HCN gas of which there will nolonger be free cyanide p...
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Started by evakahwili
Hello friends, Can someone please help me with the reason why leach solution turned blue in a vat leach tank and the possible solutions to it.
Last replied to by kahonde
this is an Fe-S-Au ore.
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Started by kahonde
hello i have been trying to vat leach a sulfidic gold ore using cyanide at 0.2% and a pH of 10.5-11 but gold of about 3g/t is still reporting in tails after 40 hours of leaching from a head of 5.88 g/t. HELP...vat leaching is the only method i can us...
Last replied to by max skinner
Yes, the above answers are good. Always when doing any type of extractive metallurgy on a sulfide gold ore  you must find out if the gold is in the sulfides or with the sulfides, a big difference. If...
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Started by Wadzanayi
The unit operation consists of vat leaching of stamp mill dumps.The dump is created after artisanal miners surrounding the custom milling center have taken out their gravity gold. Sequence of events is as follows; Site began experiencing high sol...
Last replied to by Mr_Weseni
Good day...  Mrs Wadzanayi please get in touch with me on +263717214189.... i am also facing that similar problem with our VAT leaching tanks.... Our head grade its 1.30g/t and our tailings are 1.10...
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Started by Nyasha Jawanda
hi guys what are factors that affect gold adsorption onto carbon in carbon in solution process.
Last replied to by Sugar Watkins
Activated carbon is used to recover gold from cyanide leach solutions, owing to its large surface area. There are 3 major mechanisms controlling the rate of gold adsorption onto activated carbon: 1...
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Started by m16 mine
Is there anyway you can test presence of Gold in cyanide solution using handheld electronic instruments without the use of test tubes and chemicals.
Last replied to by ThabisoKwenane
Yes. You can try using ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometry)  
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Started by Dane Smith
I have a leach feed thickener with a serious over-flocculation issue. Has anyone seen any papers/ data on the effect of synthetic flocculants on cyanide/ gold leach reactions? I know enough about the flocculant/ particle bond to know there will alway...
Last replied to by David
Hi Dane, I looked in http://www.onemine.org/ and found nothing specific to the effect of flocculant on leaching rates. I just know that too much is bad... Here is what Marsden says.
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Started by makke
We are using steel tanks with of 3000mm diameter, 3600 height and a 2400mm cone at the bottom. Agitation through air at the bottom and 15 cbm of solution. we are looking for teh ideal slurry density (ideally 30 tons of solids) for an 18 hour agitatio...
Last replied to by makke
I am sorry, I asked a question without giving all the information. we are not running a CIP or CIL. What we are trying to do is to retreat the tailings of artisanal miners without grinding. To date we...
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Started by Tumurchin
Does anyone have experience with leaching tin (cassiterite) from complex ores?  Any advise or referrals will be appreciated.
Last replied to by Bill Fraser
Hello Tumurchin, I do not think leaching tin out of cassiterite or complex ores is possible. I think you can do Alkali leaching of tin slag but not cassiterite. Tin oxide does not get chlorinat...
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Started by Mikhail
Dear colleaguesBefore my company faced an interesting challenge to design a mobile unit for gold leaching. The set includes: car an agitator for leaching pulp, filter press, a container of water and carbon column. Also auxiliary equipment, pumps, hos...
Last replied to by Mikhail
Hello & thank you! Russia also welcomes all)) If we talk about the ore, the gold recovery in 10 hours leaching is 85-90%, the original content of about 3 g/t, this amalgamation tails. The reagent us...
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Started by Andrew Eden
Hello all, I have a 40% contained copper oxide with 7% tin contained in it. And about 20 ppm Hg. What is the best way to put the copper into sulfuric acid solution and leave the Tin behind as a solid. And what to do with the mercury?  
Last commented on by Andrew Eden
It looks like its worth a shot. Cheers inOr.

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