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7
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2581
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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...
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...
7
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4681
VIEWS
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...
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...
15
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5128
VIEWS
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...
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 ...
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 ...
11
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3118
VIEWS
Started by Subhash-Kumar-Roy
Are there in general set point minimums of calcium percentage that can't affect gold stripping efficiency? Hence don't need to do acid wash.
Are there in general set point minimums of calcium percentage that can't affect gold stripping efficiency? Hence don't need to do acid wash.
Last commented on by Walter silas
Hi could you perphaps have a literature back up of a minimum calcium % on the carbon. i mean a literature that suggests a 1%is fine
Hi could you perphaps have a literature back up of a minimum calcium % on the carbon. i mean a literature that suggests a 1%is fine
4
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9383
VIEWS
Started by Sachin Prakash
How to avoid abnormal long elution period from a zadra elution circuit, is this cyanide depletion, eluant composition, flow of eluant to electrowinning cells or temperature?
How to avoid abnormal long elution period from a zadra elution circuit, is this cyanide depletion, eluant composition, flow of eluant to electrowinning cells or temperature?
3
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4070
VIEWS
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...
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...
2
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2408
VIEWS
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.
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.
I am trying to achieve purity of gold about 99.99% Using chlorauric acid for electrorefining.
1
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1467
VIEWS
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...
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....
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....
1
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2192
VIEWS
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...
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...
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...
3
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2360
VIEWS
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...
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...
3
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1856
VIEWS
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...
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...
10
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1677
VIEWS
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...
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...
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...
5
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4145
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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?
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 ...
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 ...
5
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1762
VIEWS
Started by
What are the effects of Calcium on elution?
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.
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.
22
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2767
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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?
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....
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....
10
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1474
VIEWS
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 ...
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!
Yes I have just read that report recently. There will still be a lot of work to do to get these valves sealed properly!
9
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2794
VIEWS
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?
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?
9
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1561
VIEWS
Started by Sachin Prakash
What can cause weight discrepancy in a Dore bar (Gold alloy) between the initial value (after refining and quenching) and the value after shipping from 312 m elevation to 218 m elevation.Discrepancy is about 3.5 g out of 24 kg. Sources considered:Gr...
What can cause weight discrepancy in a Dore bar (Gold alloy) between the initial value (after refining and quenching) and the value after shipping from 312 m elevation to 218 m elevation.Discrepancy is about 3.5 g out of 24 kg. Sources considered:Gr...
Last replied to by Oberfuhrer
This difference is caused by encrusted water in small pores, look at the appearance of the bars Dore, and if these have too many pores, you must first remove the water with a compressor will come out ...
This difference is caused by encrusted water in small pores, look at the appearance of the bars Dore, and if these have too many pores, you must first remove the water with a compressor will come out ...
15
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1788
VIEWS
Started by Raje Singh
What is a good coagulant for carbon fines? What is the best way to measure the temperature of a molten Dore bar in a furnace? Good software for determining angularity/roundness of carbon?Currently, we have a de-watering screen "for the stripped carbo...
What is a good coagulant for carbon fines? What is the best way to measure the temperature of a molten Dore bar in a furnace? Good software for determining angularity/roundness of carbon?Currently, we have a de-watering screen "for the stripped carbo...
Last replied to by
Suggest you try removing water faster such as a plate and frame press or vacuum rather than putting too much cost into flocculants and other devices. OK you will need to do some testing to find the ri...
Suggest you try removing water faster such as a plate and frame press or vacuum rather than putting too much cost into flocculants and other devices. OK you will need to do some testing to find the ri...
5
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1462
VIEWS
Started by Sachin Prakash
What options are there for the chemical refining silver bars with 2-5 % gold?
What options are there for the chemical refining silver bars with 2-5 % gold?
Last replied to by Sachin Prakash
Small volume for example:The precipitated from Merrill Crowe has this values in 75 kg : 0.5% Au, 22% Ag, 20% Pb and 57% Zn after the first foundry the new values in 15 kg are 2% Au, 88% Ag, the rest P...
Small volume for example:The precipitated from Merrill Crowe has this values in 75 kg : 0.5% Au, 22% Ag, 20% Pb and 57% Zn after the first foundry the new values in 15 kg are 2% Au, 88% Ag, the rest P...
10
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6005
VIEWS
Started by Raje Singh
Is there any suitable oxidizing agent for conversion of copper nitrate into copper oxide which will be useful in separation of copper from silver nitrate electrolyte in HSSR process?
Is there any suitable oxidizing agent for conversion of copper nitrate into copper oxide which will be useful in separation of copper from silver nitrate electrolyte in HSSR process?
Last replied to by Unterstarm
I agree; you can see a detailed explanation in United States patent US 8,282,903 B2
I agree; you can see a detailed explanation in United States patent US 8,282,903 B2
14
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3029
VIEWS
Started by Sachin Prakash
We prepare our gold concentrate, which contains about 8ppm Ag, for smelt through treatment with nitric acid? This silver is not seen in the final bullion because I suppose it is dissolved in the nitric acid as silver nitrate. I want to recover this s...
We prepare our gold concentrate, which contains about 8ppm Ag, for smelt through treatment with nitric acid? This silver is not seen in the final bullion because I suppose it is dissolved in the nitric acid as silver nitrate. I want to recover this s...
Last replied to by
Addition of the Chloride has to be such that the [Cl-] is kept in exact stoichiometric balance to the silver molarity, too little silver nitrate will remain room much and soluble silver di Chl...
Addition of the Chloride has to be such that the [Cl-] is kept in exact stoichiometric balance to the silver molarity, too little silver nitrate will remain room much and soluble silver di Chl...
14
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3401
VIEWS
Started by Rahil Khan
What might be the some of the possible causes of high Au on Barren Carbon after elution (AARL), when all your temperatures, pressures and flow rates are good!
What might be the some of the possible causes of high Au on Barren Carbon after elution (AARL), when all your temperatures, pressures and flow rates are good!
Last replied to by Standartenfurer
Poor acid washing resulting in inorganic fouling can definitely increase your barren grades. At a previous mine we had many problems with acid washing such that we were not acid washing for almost one...
Poor acid washing resulting in inorganic fouling can definitely increase your barren grades. At a previous mine we had many problems with acid washing such that we were not acid washing for almost one...
6
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1749
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Started by
How I can prevent oxidation in the anodes in electro-winning cell to get gold in cathodes?
How I can prevent oxidation in the anodes in electro-winning cell to get gold in cathodes?
Last replied to by Obergruppenfuhrer
In addition to the previous points (low caustic, high chloride levels, and high current density) you will get corrosion if your flow rate through the cell is too low. Typical safe flows are about 7m3...
In addition to the previous points (low caustic, high chloride levels, and high current density) you will get corrosion if your flow rate through the cell is too low. Typical safe flows are about 7m3...
14
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2091
VIEWS
Started by Tarun Karakoti
I need some data for approximate carbon losses as fines after regeneration of carbon (every cycle) and after new carbon attrition.
I need some data for approximate carbon losses as fines after regeneration of carbon (every cycle) and after new carbon attrition.
Last replied to by Oberstorm
The manufacturer considers normal to lose up to 4% of carbon after each cycle. In the regeneration process are the main attrition.
The manufacturer considers normal to lose up to 4% of carbon after each cycle. In the regeneration process are the main attrition.
25
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3794
VIEWS
Started by
When testing for Au concentrations using Lead Collection Fire Assay Methods; what valuable information is lost when only conducting Fire Assays?
When testing for Au concentrations using Lead Collection Fire Assay Methods; what valuable information is lost when only conducting Fire Assays?
Last replied to by Hauptsturm
Concentration and temperature are two fundamental kinetic drivers in any chemical reaction. Could it be that as you increase cyanide concentration you overcome the activation energy required for chemi...
Concentration and temperature are two fundamental kinetic drivers in any chemical reaction. Could it be that as you increase cyanide concentration you overcome the activation energy required for chemi...
3
REPLIES
1216
VIEWS
Started by Amar
How can we separate out Pb, Cu, Sb impurities from BiCl3 solution? Ultimate target is to produce salable Bi-compound.
How can we separate out Pb, Cu, Sb impurities from BiCl3 solution? Ultimate target is to produce salable Bi-compound.
Last replied to by OberstGruppen
Chlorination roasting should solve part of your problem instead of acid leaching. BiCl3 fumes at low temperature.
Chlorination roasting should solve part of your problem instead of acid leaching. BiCl3 fumes at low temperature.
9
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1676
VIEWS
Started by Tarun Karakoti
Fire assays are returning double the Au reading when using a standard aqua regia method. Suggestions are that the preg robbing material could be adsorbing the gold during the acid digest, which would not be transferred to the aqueous phase to organic...
Fire assays are returning double the Au reading when using a standard aqua regia method. Suggestions are that the preg robbing material could be adsorbing the gold during the acid digest, which would not be transferred to the aqueous phase to organic...
Last replied to by
It is a possibility, pay close attention to your ashing temperature and time. Higher and longer are not necessarily better.
It is a possibility, pay close attention to your ashing temperature and time. Higher and longer are not necessarily better.
9
REPLIES
2067
VIEWS
Started by Paul Morrow
I have question about Electrowinning with (NaCn Solution and H2o2) what is the best Amperage to get maximum result? How to test if there is no more gold in the solution?
I have question about Electrowinning with (NaCn Solution and H2o2) what is the best Amperage to get maximum result? How to test if there is no more gold in the solution?
Last replied to by Sudhirkumar
Sorry did not see earlier comments about the absence of AAS/FA; suggest you access Vogel's text on Qualitative Analyses there are a number of easy colorimetric techniques to define the presence of sol...
Sorry did not see earlier comments about the absence of AAS/FA; suggest you access Vogel's text on Qualitative Analyses there are a number of easy colorimetric techniques to define the presence of sol...
3
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1408
VIEWS
Started by Hauptsturm
What do you think about controlling the electric current through the dosage of sodium hydroxide?We have problems with control the electric current in the electrowinning. The actual concentration is 1,5% (NaOH), the pH is 11,0 to 11,8 in the solution....
What do you think about controlling the electric current through the dosage of sodium hydroxide?We have problems with control the electric current in the electrowinning. The actual concentration is 1,5% (NaOH), the pH is 11,0 to 11,8 in the solution....
Last replied to by Obergruppenfuhrer
Caustic levels below 0.75% will cost you electrowinning efficiency. Many operations run as high as 2% caustic. It is important to determine the caustic level by titration and not just control by pH. I...
Caustic levels below 0.75% will cost you electrowinning efficiency. Many operations run as high as 2% caustic. It is important to determine the caustic level by titration and not just control by pH. I...
1
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3357
VIEWS
Started by jeremy_911met
Hi, my name is jeremy and a geologist, hence the simple questionWhat is the minimum feed size fraction for tin smelting. In other words, at what feed size causes the Cassiterite ore to vaporise and you lose the tin?
Hi, my name is jeremy and a geologist, hence the simple questionWhat is the minimum feed size fraction for tin smelting. In other words, at what feed size causes the Cassiterite ore to vaporise and you lose the tin?
Last replied to by David
Hi Jeremy,I do not think size matters much. Maybe 100 mesh. See the PDF here at movie.https://www.youtube.com/watch?v=IKqTCvMEodA
Hi Jeremy,I do not think size matters much. Maybe 100 mesh. See the PDF here at movie.https://www.youtube.com/watch?v=IKqTCvMEodA
i totally agree with you, most of time the poor elution performance is caused by temperature and flow rate as he explained above and about high barren carbon is caused by poor elution which in turn ca...