Gravity Separation & Concentration Methods

Gravity Separation & Concentration Methods

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Started by Blackcows
Has anyone built or seen a nugget trap design to catch oversized gold coming out of a large trommel. Trommel screen holes are 12mm * 20mm so anything over 20mm is ending up in the oversize. Have found a few large nuggets with the detector. Plant oper...
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Last replied to by rob riggir
Hi David, Did you ever resolve your issue?  Cheers, Rob
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Started by JJ1
Hi Am trying to work out what the grade of a concentrate will be. I have the ore head grade fed to the float plant, the optimal flotation recovery rate and corresponding mass pull.  Are these all that is needed to calculate the concentrate grade o...
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Last replied to by Jorge
If you know the head grade, mass pull and metal recovery, it is possible to calculate the concentrate grade. This consideration is valid for two products (concentrate and tails). It is necessary to pe...
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Started by Millza79
Hi all, What is the lowest DMC medium SG that is realistically possible in a coal prep plant and why?
Last replied to by SmartDog
The dense media specific gravity is based on the amount of medium that is suspended in the water.  So the answer to your question is obviously 1.0 which is when you have no media added.  In effect t...
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Started by Millza79
We are reviewing some testwork for a client. In their plant flowsheet, they have three stages of gravity separation (Knelsons), but in the testwork they only did two stages.   Is this reasonable, or should they have done a 3rd stage to replicate t...
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Last replied to by Todd H
The plant and lab are not fully connected in testing.  What matters is did the lab work achieve the results required.  Lab units are more efficient than plant units and they also treat the whole str...
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332
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Started by Blackcows
Does anyone know what the right back pressure settings should be relating to a G700M Great concentrator. Pretty much the same as the big Knelson. We are losing fine gold in the tails still. Can't find anyone who know much about concentrators in gener...
Last replied to by David
" Pretty much the same as the big Knelson" PS: The only thing that is "pretty much the same as the big Knelson" is a Falcon & The only thing that is "pretty much the same as the big Falcon" is a Knel...
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Started by Yathil
I am looking for methods that you may have for the separation of Alumina from MgO. I am working on a design for a refractory brick recycling plant and I need to separate these 2 oxides to have a viable final product.
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Last replied to by Todd H
It is not easy to separate oxides of this nature. Gravity wont work because their density is similar.  You could you pyrometallurgy but that is difficult and expensive.  I think you only option is t...
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396
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Started by Cpt.Popeye
Hello everyone. I am not really sure about the point of this site and I am probably doing something wrong but I am a mining engineering student and having a hard time with this question.Is it possible for me to get some help to understand and solve t...
Last replied to by SmartDog
Start here: https://www.911metallurgist.com/blog/hydrocyclone-efficiency-curves
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475
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Started by usman hameed
We are dealing in gold washing/placer gold mining at the Northern side of Pakistan. Unfortunately, the placer mining industry has not been flourished in Pakistan yet. The use of primitive gold washing techniques i.e., panning is common.  The gold r...
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Last replied to by
In placer gold mines, gold usually exists in the form of single natural gold, and its density is generally greater than 16 tons/m3, which has a large difference with the density of gangue. Therefore, ...
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351
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Started by richardh
Hi  I need some assistance on something very new to me. Has anyone had any experience with a DMS cyclone using fine Barite as the medium? If so what would be the parameters used in terms of cyclone configuration and feed parameters?   Thanks R...
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Last commented on by richardh
Hi Thabo, I'm fully on top of standard FeSi/Magnetite media circuits. Barite was used in Barvoys medium baths, read up on that and you'll see the recovery method used, which was flotation. Farly old ...
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804
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Started by Gerbrand
Hi Guy's I am new to your site. I was reading with interest discussions on the gravemetric processes to concentrate diamonds. I see references to soil/ clay used as medium to form the dense slurry . Could you enlighten me on what materials are used f...
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Last commented on by richardh
Hi Gerband, the kimberlite overburden itself is used and the smectite clays form a type of medium. This is fairly old technology and was/still used in areas like Kimberely and once the medium is made ...
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658
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Started by David
We installed our iCon i150  some time back but something isn’t ok as there is no separation of gold and black sands despite following all the procedures. I wonder if there is perhaps a problem withthe electric engine RPM not being high enough....A...
Last replied to by Gene Cheeseman
From my experience high upgrade ratios will be difficult as the black sand tends to saturate the bowl quite quickly.  The high fluidizing flow reccomendation is correct as it will keep the riffles di...
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739
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Started by Reid
Hello Everyone, Thank you for your time.  I would like feedback on a project we attempted years ago, and would be interested in your input. I guess it would be best to tell you about the back story of what we are trying to do.  About 12 years ago...
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Last commented on by Glymin
Hi, do you know if the metals in your water are Cation or Anion ? What kind of analysis to get your metal quantities ?
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706
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Started by midnightcrazy
Hello and welcome everyone. Thank you for your time reading this post. My name is Martin, 3rd year Petroleum Engineering student. As a part of my project I am designing a hydrocyclone to separate solid micro particles (clay and silt) from the liquid...
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Last replied to by midnightcrazy
Thank you SmartDog, greatly appreciated. I'm checking it now.
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421
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Started by MMKG
Hi community, I'm an ambitious graduate mechanical engineer trying to find a way of making emerald mining easier. Lets say we were to put the rocks containing the emerald through a crusher, could we then apply the HMS process to the substance and get...
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Last commented on by MMKG
Thanks for your response. Very informative. At the mine where I worked for experience,there wasn't a jig concentrator either lol
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720
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Started by Hamid72
Hello evrybody I wanna to know after performing davis tube test for a iron ore sample how can we predict the number of roughing and cleaning stage for plant design? Is this completely on previous experience? Thanks for your guidance
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Last replied to by Todd H
The Davis tube only gives you a rough idea of whether the material is separable by magnetic methods.  It cant/should be used to define a flowsheet.  You need a more detailed laboratory test using we...
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798
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Started by darylwise
How do I set up a plant or operation to beneficiate Lithium Ore? We are mining Lithium Ore which is between 1.0% to 1.4%. We would like to start beneficiating it. We are looking for a simple process, do it yourself type of process. Our production pl...
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Last replied to by Todd H
The answer is it depends on your mineralogy.  What is your lithium host mineral hectorite, spodumene, claystone, etc..  Also do you want to produce a final product like lithium carbonate, hydroxide,...
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846
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Started by Jackpot Joe
I had the opportunity to clean a rifle range.  I came here.  I learned. I built here it is: https://youtu.be/N_LRjNRIxAs It was done out of a wheelchair with what I had laying around.  So don't be too hard on me. It work's great that is what cou...
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Last commented on by Jackpot Joe
I was under great time and funds limits. No power had to haul water in barrels. It rained and rained I was dealing with a muck and bullets mix at times water running out of the back stop dead center r...
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1361
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Started by Seeker
Please help me! I have mixed metal dusts ( coarse grains ) of copper, solder & aluminum. Can I separate all those metals by using Air Knife for grain separation? Link to the video: https://www.youtube.com/watch?v=tVu3_0l0tmE Thanks in advance!
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Last replied to by Todd H
There is big difference between the SG of grain and that of metal!  It might work with some modifications.  Why not look at using a shaking table? Google it there are lots of videos. Regards Todd
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Started by j.honarpazhouh
hello everyone We have hematite deposit that Our ore contain hematite(65%), quartz(25%) and feldspar(10%), and at 400 micron about 80 percent of our hematite particles are free. in your opinion Can I use Reichert cone for ore concentrating? And whic...
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Last replied to by m_aazami
Dear Dr. Honarpazhouh Greeting For your information the best gravitational method for  concentration of hematite is spiral system and Reichert cone has lower priority in comparison with spiral.  ...
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737
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Started by JGR
Hi, I have extensive experience in DMS for a number of commodities however, I have been asked to investigate the use of rotary pans for the recovery of diamonds. I have spent some time on the web trying to find a fairly detailed process flow diagram ...
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Last replied to by rob riggir
Hi Ian, I can help you with your investigations, having been involved with the operation and design of diamond pans in South Africa, Brazil and Australia. I have design calculations as well. You ca...
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1162
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Started by Peter J
What equipment is best to separate mill oversize from carbon after a disastrous mill run put about 200tons of grit into CIP circuit? I once used a spiral wheel but it would be very slow at this tonnage:  Would an agricultural grain destoner work?
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Last replied to by SIMetallurgist
We use a coal spiral to separate grit and carbon. Our ore SG in 2.6 so similar to yours.
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860
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Started by Char
Hi, can someone tell me from experience, what the smallest gold particle size is that will fall through water due to gravity of 1g? I.e. will not stay suspended. If possible, can you give a range for clear and silty water? Thanks C    
C
Last replied to by Char
Thanks SmartDog for the response and links. Much appreciated. There is a lot of interesting topics on your website that will keep me busy for a while. Regards, c  
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682
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Started by Hamid72
Hello everyone We have an manganese deposit that contain todorokite, cryptomelane, pyrolusite, hausmannite. at 60 micron about 80 percent of our manganese particles are free. in your opinion what is the best method for this ore concentrating? thank...
Last replied to by SmartDog
Flotation
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682
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Started by Cash Positive
Has anyone done any research with light spectrum to increase recovery on gold table? Has anyone done any work with different light spectrums and or dyes to increase recovering on gold shaker tables?
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Last replied to by Todd H
I am not sure that anything you do will change your ability to influence the table performance - I would simply experiment and use assays to zero in on the right settings.  Tables are fairly rudiment...
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778
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Started by Eduardo JImenez
Good day for all: Do sanding in cilindrical flotation cells, Wemco type, in continiuos service, will produce an increase or decrease in motor power draw? https://www.google.com/search?q=fls+flotation+cells&rlz=1C1GCEU_enCL842CL842&source=lnms&tbm=i...
Last replied to by SmartDog
First off let us discuss why and how sanding occurs, because that does have an impact.  Sanding can occur for many reasons, the two main and most common being; 1) poor classification ahead of flotati...
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Started by tichalfred
On carrying out tracer tests on a HMS cyclone; the tracers of varying density report to both the floats and the sinks. Seems no separation is occuring and it's a random placement of the tracers. Have varied the pressure and SG to no avail. Have also ...
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Last replied to by richardh
tichalfred Hi, sorry. I have been off line for a while. In terms of DMS. What are your cyclone dimensions, i.e. size, cone angle etc. What is the mineral you are sorting? What are is the medium you...
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967
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Started by Sam
I recently purchased a trommel from a friend. It was built by an engineer who is now deceased. It incorporates a shaker deck, a scrubber trommel and a jig. It works fine without the jig (sluicing). The friend didn’t use it. I am curious as to what ...
Last replied to by David
Hi Mike, here is what Sam sent me  https://youtu.be/ysFnPB57zXY
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675
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Started by ALanyon
Hi,   I am wanting to examine some methods to reduce the vibration in our Falcon unit. Primarily the high vibration occurs early in the cycle (first 5 minutes). I can see the fluidized bed coming away from the bowl when the high level of vibration...
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Last commented on by ALanyon
Thanks for the input. From what I can tell our fluidizing pressure is adequate, running at around 6.2 BAR. I think your second point about sporadic dense feed is more likely the case as the vibrati...
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831
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Started by Millza79
Hi all, could somebody please tell me the typical top size/maximum size that can feed a Knelson and a Falcon?
Last replied to by Gene Cheeseman
Typically the recommended protection screen size would be 10M (2 mm).  They can handle particles up to 1/4" as SmartDog mentioned but you will see a massive increase in wear rates with minimal benef...
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698
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Started by Peter.Li
Hello guys, I am doing a GRG test and analyzing the results according to the paper "Laboratory procedure to characterize gravity-recoverable gold" . I do not know the meaning of "Yield", "Calc.: 4.787 g/t" in Table 2 and how to calculate them.  I ...
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934
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Started by B James
Warning: I am no chemist, so excuse me if I seem green.   How I ended up with Sodium Aluminate: This is a by product from dissolving cast aluminum with sodium hydroxide mixed with hotter and heated. I do this in very small batches. 55 gallon dru...
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559
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Started by spsatyananda05
I've activated bentonite with HCl. due to the activation the SiO2 has increased and Al2O3 decreased, i don't have the reason why the SiO2 has increased and Al2O3 decreased. Do anyone know the exact reason why this change happening?
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Last replied to by Jorge
Al2O3 is partially leached. If you perform the activation using different levels of HCl, the leaching will increased gradually with increasing HCl concentration. In this way, the relative SiO2 cont...
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659
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Started by Sam
I have a project in Arizona. Old manganese mines that contain medium quality gold ore. The manganese ranges from10% to plus 30%. I have 900 tons of ore reserves on two small claims. Water is an issue. Lack of it. I have captured gold via dry washing ...
Last replied to by SmartDog
The big issue is the amount of ore you have.  900 tons is not a lot of ore. Any system beyond what you are already have is going to be in the 50+ t/hr range and cost over $50,000 plus auxiliary equip...
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934
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Started by Raulacun
I have a Knelson 7.5 with vibrating screen. Someone stole the electric motors of the concentrator and the screen. To replace them locally, I need to know the rpm of the motor and the diameter of the original pulley, here we use 110/220 V 60 hz monofa...
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Last replied to by jaimecarmonaa@gmail.com
Good morning Raul. Chris' answer is correct. You should only know that the cone should rotate at 400 RPM. Commercially the 3 / 4HP engine can be purchased at 1750 RPM. I do not remember the diameter...
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688
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Started by tom peragine
Being a gold prospector for years, I have used small amounts of mercury to recover the fine pieces. A buddy found a large vial of mercury and gave it to me, but it's not shiny clean. The vial seems heavy, even including the water/mercury ratio. It se...
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Last replied to by Todd H
Tom, Mercury is tough as no one wants to test it anymore due to the environmental issues.  Its color could be any number of contaminants.  Burning off a small portion is going to be pretty dangero...

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