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1817
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Started by Amar
Professor gave me an Eh meter that it isn't calibrated.I want know how I can make calibrated an Eh meter.If I can make its calibrated, then I can use it.
Professor gave me an Eh meter that it isn't calibrated.I want know how I can make calibrated an Eh meter.If I can make its calibrated, then I can use it.
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1585
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Started by
In a Acid water treatment System with hydrated lime, if the amount of Sulfates (SO4(2-)), ranges between 60 and 120 mg/L, Fe ranges between 3-5 mg/L, and Aluminum ranges 2-5 mg/L, Fe can be eliminated as Fe(OH)3, and Aluminum as Gibbsite (Al(OH)3)), ...
In a Acid water treatment System with hydrated lime, if the amount of Sulfates (SO4(2-)), ranges between 60 and 120 mg/L, Fe ranges between 3-5 mg/L, and Aluminum ranges 2-5 mg/L, Fe can be eliminated as Fe(OH)3, and Aluminum as Gibbsite (Al(OH)3)), ...
Last replied to by Maya Rothman
Thanks for your reply. At the time of writing I was not aware it was an existing system. Yes, if you have an existing system it's hard to convince people to invest in capital expenditure. I am not sur...
Thanks for your reply. At the time of writing I was not aware it was an existing system. Yes, if you have an existing system it's hard to convince people to invest in capital expenditure. I am not sur...
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1689
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Started by
Under what conditions is really a feasible option for reverse osmosis plant, to treat Acid rock drainage?
Under what conditions is really a feasible option for reverse osmosis plant, to treat Acid rock drainage?
Last replied to by
When we talk about treatment of mine water, RO is simply a unit operation that concentrates contaminated water - not so much a "water treatment" process in its own right. Pre-treatment of mine water a...
When we talk about treatment of mine water, RO is simply a unit operation that concentrates contaminated water - not so much a "water treatment" process in its own right. Pre-treatment of mine water a...
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1522
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Started by Zander Barcalow
Does anyone have a PHREEQC file that can exemplify the arsenopyrite oxidation along the time in a column experiment? I have the mineralogical data (Rietveld X-ray), chemical composition (52 elements) and acid-base account data of the solids.Being mor...
Does anyone have a PHREEQC file that can exemplify the arsenopyrite oxidation along the time in a column experiment? I have the mineralogical data (Rietveld X-ray), chemical composition (52 elements) and acid-base account data of the solids.Being mor...
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1428
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Started by Jean Rasczak
Does anybody know what the most active Universities in this field? Who is funding more projects, PhDs, publications?
Does anybody know what the most active Universities in this field? Who is funding more projects, PhDs, publications?
Last replied to by
In Spain some of the most active universities are:Universidad de Huelva - Prof Jose Miguel NietoUniversidad de Oviedo - Prof Jorge LoredoInstitute of Environmental Assessment and Water Research (IDAEA...
In Spain some of the most active universities are:Universidad de Huelva - Prof Jose Miguel NietoUniversidad de Oviedo - Prof Jorge LoredoInstitute of Environmental Assessment and Water Research (IDAEA...
9
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1459
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Started by
I am new into the AMD topic. Does anyone know a good source to catch up with the most up to date AMD remediation technologies? (Proven and not-proven technologies) other than www.gardguide.com
I am new into the AMD topic. Does anyone know a good source to catch up with the most up to date AMD remediation technologies? (Proven and not-proven technologies) other than www.gardguide.com
Last replied to by OberstGruppen
Also try here http://www.infomine.com/publications/search.asp?action=16384&search_text=acid%20drainage&search_dt_all=true&search_type=and&search_field=allanother onehttps://www.linkedin.com/pulse/mine...
Also try here http://www.infomine.com/publications/search.asp?action=16384&search_text=acid%20drainage&search_dt_all=true&search_type=and&search_field=allanother onehttps://www.linkedin.com/pulse/mine...
4
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1373
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Started by
Does anyone have information (based on field data, preferably, but a well-documented experiment also would be helpful) they can share for a reaction path under partially-saturated conditions for a conversion of Jarosite to Melanterite (or another hyd...
Does anyone have information (based on field data, preferably, but a well-documented experiment also would be helpful) they can share for a reaction path under partially-saturated conditions for a conversion of Jarosite to Melanterite (or another hyd...
Last replied to by
Alas, no sealed, old samples - I agree that would be a neat experiment (and we may try that). I am hesitant to use H2 (because I don't want to introduce a new electron donor that is not present), but ...
Alas, no sealed, old samples - I agree that would be a neat experiment (and we may try that). I am hesitant to use H2 (because I don't want to introduce a new electron donor that is not present), but ...
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1437
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Started by Marshal Meru
It is now apparent that sulphide waste dumps are associated with an unrecognized atmospheric hazard. Following the confined space accident at Sullivan mine, it became apparent that sulfide waste dumps are associated with an unrecognized atmospheric h...
It is now apparent that sulphide waste dumps are associated with an unrecognized atmospheric hazard. Following the confined space accident at Sullivan mine, it became apparent that sulfide waste dumps are associated with an unrecognized atmospheric h...
Last replied to by Marshal Meru
That is true. The risk at Number 1 Shaft Dump was high during May (the time of accident). However, the risk would be higher during the Summer.
That is true. The risk at Number 1 Shaft Dump was high during May (the time of accident). However, the risk would be higher during the Summer.
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1170
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Started by
I need to have an average composition of acid mine drainage including (pH, Heavy metals, sulfates, nitrates etc), It is an information that will help me to have a general idea on the range of various minerals found in acid mine drainage. Also can i g...
I need to have an average composition of acid mine drainage including (pH, Heavy metals, sulfates, nitrates etc), It is an information that will help me to have a general idea on the range of various minerals found in acid mine drainage. Also can i g...
Last replied to by Obersturmbann
Well, i need to know whether you are looking for composition of AMD from coal mine or metal mines, or both, because the metal concentrations significantly varied between two.
Well, i need to know whether you are looking for composition of AMD from coal mine or metal mines, or both, because the metal concentrations significantly varied between two.
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1155
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Started by
Potential Major Sources of Error in Predicting Future Sulfate Levels in neutral mine drainage.Any input for the questions below would be appreciated.Not counting flow estimates and predictions, what are some major sources of error associated with mod...
Potential Major Sources of Error in Predicting Future Sulfate Levels in neutral mine drainage.Any input for the questions below would be appreciated.Not counting flow estimates and predictions, what are some major sources of error associated with mod...
Last replied to by
Thanks for elaborating important issues. One quick thought on your important comments on understanding the conceptual basis of kinetic tests. It is of central importance that design and excite test wo...
Thanks for elaborating important issues. One quick thought on your important comments on understanding the conceptual basis of kinetic tests. It is of central importance that design and excite test wo...
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1392
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Started by Victor Bergman
I am more particularly specialized in water treatment.I wanted to know if some people have had some problems with broken pump due to a deposit of barium and what solutions exist. Generally, is barium can precipitate by electrolysis or other chemical ...
I am more particularly specialized in water treatment.I wanted to know if some people have had some problems with broken pump due to a deposit of barium and what solutions exist. Generally, is barium can precipitate by electrolysis or other chemical ...
Last replied to by
My initial guess was probably correct; you have Calcium Sulfate building up on the pump. This stuff loves to build up in high energy places. I'd test the water for sulfates and if they are around 2,00...
My initial guess was probably correct; you have Calcium Sulfate building up on the pump. This stuff loves to build up in high energy places. I'd test the water for sulfates and if they are around 2,00...
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1308
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Started by Maya Rothman
3 million gallons of AMD goes into Animas River bring heavy metals as well as mustard colour.
3 million gallons of AMD goes into Animas River bring heavy metals as well as mustard colour.
Last replied to by
Video of the event remarkablehttps://www.facebook.com/Mark.Douglas.Canfield/videos/1648111835426695/?pnref=story
Video of the event remarkablehttps://www.facebook.com/Mark.Douglas.Canfield/videos/1648111835426695/?pnref=story
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1528
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Started by
I am working in a Titration model of acid water with hydrated lime - In the below PHREQC code, why gypsum does not precipitates?SOLUTION 1 pH 3.62unit mg/ltemp 16.0Na 3.6K 3.9Ca 3.7Mg 2.5Cl 1S(6) 93 as SO4Fe(+3) 3.5Zn 0.15Al 3.9Mn(+3) 0.61Cu
I am working in a Titration model of acid water with hydrated lime - In the below PHREQC code, why gypsum does not precipitates?SOLUTION 1 pH 3.62unit mg/ltemp 16.0Na 3.6K 3.9Ca 3.7Mg 2.5Cl 1S(6) 93 as SO4Fe(+3) 3.5Zn 0.15Al 3.9Mn(+3) 0.61Cu
Last replied to by
I think the basic answer is that the sulphate concentrations are very low and therefore it takes a large amount of Ca to approach saturation with respect to gypsum. In fact, it looks like gypsum satur...
I think the basic answer is that the sulphate concentrations are very low and therefore it takes a large amount of Ca to approach saturation with respect to gypsum. In fact, it looks like gypsum satur...
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1704
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Started by
Has anyone seen defensible water quality or tailings geochemical data regarding the Samarco tailings toxicity? There are a lot of news reports citing toxicity but I could not find much in the way of details or supporting evidence.
Has anyone seen defensible water quality or tailings geochemical data regarding the Samarco tailings toxicity? There are a lot of news reports citing toxicity but I could not find much in the way of details or supporting evidence.
Last replied to by
Until one knows exactly what the material is, it is impossible to say who is correct. There is clearly a propaganda war going on and everyone is just expected to swallow what they're told (by both sid...
Until one knows exactly what the material is, it is impossible to say who is correct. There is clearly a propaganda war going on and everyone is just expected to swallow what they're told (by both sid...
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1367
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Started by Kumar Choudhry
I am looking for summary or a literature on innovative and cost effective methods for AMD treatment to be converted to potable water, agricultural water etc.
I am looking for summary or a literature on innovative and cost effective methods for AMD treatment to be converted to potable water, agricultural water etc.
Last replied to by Standartenfurer
Our efforts are focused in AMD alkaline typical treatment followed by an acidification and modification with nutrients in order to produce irrigation water. All of our projects have as main goal the b...
Our efforts are focused in AMD alkaline typical treatment followed by an acidification and modification with nutrients in order to produce irrigation water. All of our projects have as main goal the b...
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1411
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Started by Paul Morrow
How is possible to extrapolate the information from Humidity cells tests (HCT) along the time? It is possible?
How is possible to extrapolate the information from Humidity cells tests (HCT) along the time? It is possible?
Last replied to by Obergruppenfuhrer
It depends on what you conclusions you are trying to extrapolate. SRK uses HCTs extensively to predict drainage characteristics of waste rock, tailings and reactive surfaces. The trick is the use of s...
It depends on what you conclusions you are trying to extrapolate. SRK uses HCTs extensively to predict drainage characteristics of waste rock, tailings and reactive surfaces. The trick is the use of s...
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1764
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Started by
Depend on the ABA testing and geological model. Some lithologies have potential acid generation. We need additional neutralization capacity (limestone as CaCO3) for closure part. How to calculate average mass balance values (NP),NNP, AP etc. to predi...
Depend on the ABA testing and geological model. Some lithologies have potential acid generation. We need additional neutralization capacity (limestone as CaCO3) for closure part. How to calculate average mass balance values (NP),NNP, AP etc. to predi...
Last replied to by Standartenfurer
Also you can use the standard methods and guidance in ASTM E 1915.
Also you can use the standard methods and guidance in ASTM E 1915.
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2002
VIEWS
Started by Tarun Karakoti
Humidity Cell test: How many & how long? For instance, 1 week cycle HCT result corresponds to how many years?
Humidity Cell test: How many & how long? For instance, 1 week cycle HCT result corresponds to how many years?
Last replied to by Tarun Karakoti
Thank you all for your support, I will keep my mind to your ideas and continue deeply research HCT results and correlate with static test results.
Thank you all for your support, I will keep my mind to your ideas and continue deeply research HCT results and correlate with static test results.
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1253
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Started by Subhash-Kumar-Roy
Could you please share with me a journal, link or books about the correlation/relationship between pH, TDS, TSS, and Conductivity?
Could you please share with me a journal, link or books about the correlation/relationship between pH, TDS, TSS, and Conductivity?
Last replied to by Oberstorm
An excellent primer on natural water quality is Hem, Study and Interpretation of Chemical Characteristics of Natural Water. A bit dated but available free from the USGS. Correlation between measured c...
An excellent primer on natural water quality is Hem, Study and Interpretation of Chemical Characteristics of Natural Water. A bit dated but available free from the USGS. Correlation between measured c...
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1427
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Started by Raje Singh
Could you please send me some links of journals or books for my reference (with authors in it) that explains very details of what's happening when water, sulphide and Oxygen reacts and make AMD, like why acidity can dissolved metals in water? How aci...
Could you please send me some links of journals or books for my reference (with authors in it) that explains very details of what's happening when water, sulphide and Oxygen reacts and make AMD, like why acidity can dissolved metals in water? How aci...
Last replied to by Paul Morrow
A good start is the global acid rock drainage guide (www.gardguide.com). This site is an international project on ARD which covers the science and the practical aspects. It is comprehensive and fully ...
A good start is the global acid rock drainage guide (www.gardguide.com). This site is an international project on ARD which covers the science and the practical aspects. It is comprehensive and fully ...
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1654
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Started by Rahil Khan
I need some explanation and need books, or links or journal about it Why do the sulfur dissolve into water and the water turn into Acid mine drainage? And only sulfur can make AMD?Is there any connection/relation between grain size of ore and quality...
I need some explanation and need books, or links or journal about it Why do the sulfur dissolve into water and the water turn into Acid mine drainage? And only sulfur can make AMD?Is there any connection/relation between grain size of ore and quality...
Last replied to by Obersturmbann
The Global Acid Rock Drainage Guide (GARD Guide) is a good online resource atwww.gardguide.com. It has an explanation of the basic geochemistry of acid drainage and chapters on methods for characteriz...
The Global Acid Rock Drainage Guide (GARD Guide) is a good online resource atwww.gardguide.com. It has an explanation of the basic geochemistry of acid drainage and chapters on methods for characteriz...
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1248
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Started by Sudhirkumar
I need your help againcould you please send me some links of journals or books for my reference (with authors in it) that show and explain minerals which act as base in solution? And I have result from thin section's lab it came out with mineral kua...
I need your help againcould you please send me some links of journals or books for my reference (with authors in it) that show and explain minerals which act as base in solution? And I have result from thin section's lab it came out with mineral kua...
Last replied to by Hauptsturm
Apart from the oxidation of sulphide minerals and dissolution of acid consuming minerals, pH will also be controlled by the precipitation and dissolution of secondary minerals. In order to be sure, ha...
Apart from the oxidation of sulphide minerals and dissolution of acid consuming minerals, pH will also be controlled by the precipitation and dissolution of secondary minerals. In order to be sure, ha...
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Started by Sandeep Bisht
I’m a student from mining engineering, could you help me with books, and journal and anything related to "Determination of limestone dose of AMD" your help will be great.
I’m a student from mining engineering, could you help me with books, and journal and anything related to "Determination of limestone dose of AMD" your help will be great.
Last replied to by Sandeep Bisht
Thank you all for your recommendation 🙂 How so, according to some literature that I have read, limestone got the highest percentage on reducing acid in AMD?
Thank you all for your recommendation 🙂 How so, according to some literature that I have read, limestone got the highest percentage on reducing acid in AMD?
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1232
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Started by Kumar Choudhry
I got questions: Do we need time to reduce metal in AMD?Is there any impact if I make just 2 settling pond and 4 settling pond in reducing TSS, Metals and pH in AMD?
I got questions: Do we need time to reduce metal in AMD?Is there any impact if I make just 2 settling pond and 4 settling pond in reducing TSS, Metals and pH in AMD?
Last replied to by Gruppen
When using ponds as the sole source of precipitating metal, I highly recommend a duplicate system, by which as one set of ponds fill up (thus the detention time is reduced), the other set can be used....
When using ponds as the sole source of precipitating metal, I highly recommend a duplicate system, by which as one set of ponds fill up (thus the detention time is reduced), the other set can be used....
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1885
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Started by Bob Mathias
I am interested in obtaining synthetic pyrite for research purposes. Does anyone know of any international organizations that supply synthetic pyrite?
I am interested in obtaining synthetic pyrite for research purposes. Does anyone know of any international organizations that supply synthetic pyrite?
Last replied to by
https://www-s.nist.gov/srmors/viewTable.cfm?tableid=82NIST also has a pyrite standard for use as a control in bioleaching.
https://www-s.nist.gov/srmors/viewTable.cfm?tableid=82NIST also has a pyrite standard for use as a control in bioleaching.
79
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6061
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Started by
Government regulators are beginning to ask proposed or operating mines to treat for sulphate. As I become involved in these projects, I see that this is a daunting challenge and I would like to hear from people who have experience in this area. As a...
Government regulators are beginning to ask proposed or operating mines to treat for sulphate. As I become involved in these projects, I see that this is a daunting challenge and I would like to hear from people who have experience in this area. As a...
Last replied to by Marshal Meru
Let me know if you need any help with the round-robin.
Let me know if you need any help with the round-robin.
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1484
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Started by OberstGruppen
CSIRO has been active over the past few years developing and patenting an alternative to lime based on hydrotalcite precipitation.
CSIRO has been active over the past few years developing and patenting an alternative to lime based on hydrotalcite precipitation.
Last replied to by OberstGruppen
Thank you for your input - much appreciated. I am aware of the use of MgOas an alternative to CaO. What differentiates the hydrotalcite (HT)-basedtechnique is the requirement to optimise the M2+ to M3...
Thank you for your input - much appreciated. I am aware of the use of MgOas an alternative to CaO. What differentiates the hydrotalcite (HT)-basedtechnique is the requirement to optimise the M2+ to M3...
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1290
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Started by Obergruppenfuhrer
Can anyone recommend for removal of arsenic and aluminum ion from the leachate collecting pond? I found some methods but i want to get benefit from your experiences.
Can anyone recommend for removal of arsenic and aluminum ion from the leachate collecting pond? I found some methods but i want to get benefit from your experiences.
Last replied to by
Maybe start from a fundamental level. Al is strongly pH-dependent and can be removed quantitatively (certainly to levels of environmental concern) by manipulating the pH. This is the standard basis fo...
Maybe start from a fundamental level. Al is strongly pH-dependent and can be removed quantitatively (certainly to levels of environmental concern) by manipulating the pH. This is the standard basis fo...
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Started by Gruppen
How can I relate short term leach test results with releasing time, releasing percentage and PPE? Can I connect with whole rock analysis results and leach test results to determine releasing speed?
How can I relate short term leach test results with releasing time, releasing percentage and PPE? Can I connect with whole rock analysis results and leach test results to determine releasing speed?
Last replied to by Maya Rothman
You made such an effort in replying - but QAQC has little to do with scaling and the processes are different at different scales and the interact between the scales.
You made such an effort in replying - but QAQC has little to do with scaling and the processes are different at different scales and the interact between the scales.
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Started by Oberfuhrer
Is there any effective and efficient method (way) to forecast or model dissolved metals in water? I have 4 times LCT results
Is there any effective and efficient method (way) to forecast or model dissolved metals in water? I have 4 times LCT results
Last replied to by Bob Mathias
The best way to "forecast" is to build a predictive geochemical model. This includes, but is not limited to: an appropriate conceptual model, a reasonable accurate water balance, an associated mass ba...
The best way to "forecast" is to build a predictive geochemical model. This includes, but is not limited to: an appropriate conceptual model, a reasonable accurate water balance, an associated mass ba...
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1364
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Started by Standartenfurer
What is the track record of modern copper mines for ARD in North America? Are modern U.S. and Canadian porphyry copper mines protecting water quality?I'd like a good critique if this Earworks paper:http://www.earthworksaction.org/files/publications/P...
What is the track record of modern copper mines for ARD in North America? Are modern U.S. and Canadian porphyry copper mines protecting water quality?I'd like a good critique if this Earworks paper:http://www.earthworksaction.org/files/publications/P...
Last replied to by Standartenfurer
The paper does use all post-NEPA mines but selection was purposeful, not random. I disagree with EPA's current pre-emptive veto action, but Pebble is a unique project in a unique place. Does it need d...
The paper does use all post-NEPA mines but selection was purposeful, not random. I disagree with EPA's current pre-emptive veto action, but Pebble is a unique project in a unique place. Does it need d...
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1333
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Started by Obersturmbann
Does anyone have experience on how flood and / or drought affect the water quality of pit lakes? I appreciate any bibliographical reference with this acid mine drainage ARD topic.
Does anyone have experience on how flood and / or drought affect the water quality of pit lakes? I appreciate any bibliographical reference with this acid mine drainage ARD topic.
Last replied to by
On the surface aspects of AMD, I was able to monitor the effects of monsoon at a copper mine in India. The first one is a quick flush of surface waterways and exposed AMD-affected rocks and waste. It ...
On the surface aspects of AMD, I was able to monitor the effects of monsoon at a copper mine in India. The first one is a quick flush of surface waterways and exposed AMD-affected rocks and waste. It ...
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1305
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Started by Sturmbann
Any suggestions on lab equipment / infrastructure to support a mine closure teaching, mine water management, at a mine engineering educational institute?I am a member of the SENA Educational Institute in Colombia, South America. Currently we are plan...
Any suggestions on lab equipment / infrastructure to support a mine closure teaching, mine water management, at a mine engineering educational institute?I am a member of the SENA Educational Institute in Colombia, South America. Currently we are plan...
Last replied to by Zander Barcalow
Your educational goals are admirable; I am quite envious. The Colombian government too should be applauded for its willingness to fund your group. As a passive treatment design engineer, I would recom...
Your educational goals are admirable; I am quite envious. The Colombian government too should be applauded for its willingness to fund your group. As a passive treatment design engineer, I would recom...
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1621
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Started by Hauptsturm
We are using the terms “mine water”, “mine drainage” of “mine effluent” on a daily basis – but do we have a definition for this expression?If you know one from your country or use one, could you please post it here, as I am currently pu...
We are using the terms “mine water”, “mine drainage” of “mine effluent” on a daily basis – but do we have a definition for this expression?If you know one from your country or use one, could you please post it here, as I am currently pu...
Last replied to by Bob Mathias
To confuse the issue further, as of late some differentiate mine drainage into two parts: acid mine drainage and neutral mine drainage; the former being self explanatory while the latter would be mine...
To confuse the issue further, as of late some differentiate mine drainage into two parts: acid mine drainage and neutral mine drainage; the former being self explanatory while the latter would be mine...
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1201
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Started by Oberstorm
I read that in the processing of metal ores HCl is employed. Does this mean that later on there is a need to remove any remnants? Do chloride removal absorbents find any application within this industry?
I read that in the processing of metal ores HCl is employed. Does this mean that later on there is a need to remove any remnants? Do chloride removal absorbents find any application within this industry?
Last replied to by Sandeep Bisht
HCl is extremely corrosive to most materials of construction...likely dissolution in sulphuric, caustic or ammonia for base metals & cyanide for precious metals; in the mineral processing world, gener...
HCl is extremely corrosive to most materials of construction...likely dissolution in sulphuric, caustic or ammonia for base metals & cyanide for precious metals; in the mineral processing world, gener...
The fact that you have indicated the value is an Eh measurement rather than a redox (EMF or ORP also used interchangeably) suggests not. The EMF reading that is made in mV is a function of the type of...