• To participate in the 911Metallurgist Forums, be sure to JOINLOGIN
  • Use Add New Topic to ask a New Question/Discussion about Hydrometallurgy.
  • 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.

0
REPLIES
13
VIEWS
Started by peyman
what is the hydrolyses role in carbonization process ?
2
REPLIES
62
VIEWS
Started by nicolas
hello, i operate a gravity vat leach plant, i treat tailings from artisanal workers after recovery of free gold. I got twelve 30 tons tanks. As tails are argillaceous, i melt 15kg/ton cement to pelletize the tails . What flow rate do i need in tank ...
Last replied to by Jorge Ganoza
If you don't perform a testing program to evaluate operating parameters, the gold extraction would not be as high as you want. It is important to evaluate the pellets too. You can try 30 l/h/m2, you c...
3
REPLIES
95
VIEWS
Started by Irene Ibz
Hello, I work in a plant where there are a lot of carbon losses of about 7 to 9 tonnes per month.. Now I have been given a project to minimize the carbon losses and of course I know carbon is lost due to attrition losses in the agitators, kiln, due ...
Last commented on by Irene Ibz
Thanks a lot Jorge!
1
REPLY
41
VIEWS
Started by Fabian Rebolledo
i would like to know if someone knows about technologies that can measure the organic entrainment in copper solvent extraction without lab tests.
Last replied to by David
Typically two ways, most common is a dairy centrifuge tester see link of typical unit; https://www.indiamart.com/dairy-instruments/# Also used in a Horiba IR tester that uses infrared and special so...
3
REPLIES
125
VIEWS
Started by Mahmoud Abdelmonem
Hello I have never work in gold processing. I'm trying to understand how the circuit of the CIL process goes and the flow of ore and cyanide and carbon in it , but still somethings confused in tank design. Suppose there are 4  tanks . The ore ent...
Last replied to by Ashraf Ali
Dear mr Mohamed I have same project and I face some problem , can we discus this issue if you want can chat WhatsApp 00966535646526 
2
REPLIES
95
VIEWS
Started by kudzisa
Which ion exchange resin is the best for processing gold rich solution from a heap leaching process of oxide rich Banded Iron Formation.
Last replied to by shukeri
Hi Kudzisa A few types of resin work excellent, one of them is Minix gold selective resin. I have been working in comparing resin and activated carbon performance in carbonaceous ore and high base or...
1
REPLY
25
VIEWS
Started by Sandeep Bisht
Over a week and a half, the dissolved oxygen content of my flotation concentrate carbon-in-leach tank drops by 80% to around 5 ppm. My gold recovery is still OK at almost 90%. This is a batch/Vat setup.   What could explain the oxygen being consu...
Last replied to by Charlie
Hi Sandeep, I saw something similar discussed elsewhere and here is what they say: Susan (Sue) Ritz This sounds like a mechanical problem to me. Do you inject directly into the tank or do you have a...
8
REPLIES
121
VIEWS
Started by SDHILLBILLY
I have been experimenting with direct smelting and sulfuric acid leaching/electrowinning of oxide copper/silver ores on my property. My great grand father used direct smelt 150 tons per day. I Would like to setup a pilot process of 4 to 8 tons per da...
Last replied to by David
Some processing ideas: https://www.911metallurgist.com/blog/heap-leaching see the last 3 PDFs at bottom https://www.911metallurgist.com/blog/agitated-copper-leaching-ore https://www.911metallurgist...
6
REPLIES
259
VIEWS
Started by mashudu
our final gold bullion contains about 19% of copper whist gold fines is 65%. i would like to ask as to what flux composition can we use to reduce such high copper in the final bullion .
Last replied to by Collin Amonde
Hallo Mashudu What fluxes are you using, and what is your ratios. The ore that you treat at your plant does it have high copper content? At what Amps do you run your electrowining cells rectifier.  ...
1
REPLY
98
VIEWS
Started by Mikhail
Hello colleagues!Anyone can suggest a method of laboratory research of ores before heap leaching? I am interested in the method of determining the height of the heap. I saw a device that allows you to simulate a column of ore height of 9-12 meters. S...
Last replied to by Rheomet
Hi Mikhail, I suspect that you are rather looking for percolation response, as heap leaching specifically precludes the need for filtration, that being its key benefit. Complete Heap leach testing  ...
4
REPLIES
267
VIEWS
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?
2
REPLIES
188
VIEWS
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...
6
REPLIES
266
VIEWS
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...
5
REPLIES
290
VIEWS
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...
1
REPLY
153
VIEWS
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...
3
REPLIES
240
VIEWS
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...
1
REPLY
144
VIEWS
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 ...
1
REPLY
149
VIEWS
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...
4
REPLIES
306
VIEWS
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...
1
REPLY
213
VIEWS
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...
2
REPLIES
186
VIEWS
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. 
3
REPLIES
309
VIEWS
Started by girishchandra
Need help for recovery of copper from copper nitrate solution   
Last replied to by mishaka
In order to recover copper from you just raise PH of your solution to 6 there you will have almost 90% of copper precipitated
1
REPLY
178
VIEWS
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.
1
REPLY
198
VIEWS
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...
3
REPLIES
260
VIEWS
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%  
1
REPLY
202
VIEWS
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....
2
REPLIES
233
VIEWS
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...
2
REPLIES
223
VIEWS
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......
1
REPLY
369
VIEWS
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.
3
REPLIES
637
VIEWS
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
2
REPLIES
337
VIEWS
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 gratefulpinyasov.estageo@mail.ru
5
REPLIES
303
VIEWS
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...
1
REPLY
207
VIEWS
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...
3
REPLIES
426
VIEWS
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...
4
REPLIES
433
VIEWS
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...

Please join and login to participate and leave a comment.