Electrostatic separation of dry concentrates how to commercial or self made.

It would be interesting to test different charged sets of plates at different distances for material that is passing over them. This would give a different magnitude of the electrostatic force between these charges as the material passes over them. Maybe the air blower is more important then you may think to move the material through or over the different sets of plates.

Looks like I may need a number of transformers to make this work.
 

Amazon Forum Fav 👍

Minelab PRO-FIND 35 Waterproof Pinpointer Metal Detector for Experts with Tone ID & Adjustable Sensitivity - Grab it through Amazon!
Looks like this set up is not going to be on the light side to carry out in the field with a generator. Still once set up a lot of material can be run through. I'm still thinking that a air blower may work for moving materials or maybe a shaker.
 

If the values from the near by rock is only very fine you can see that most people will give up on it as they are not able to recover this type of very fine size values. This is the real reason I'm willing to check this out.
 

If I have some positive results from this I may not post it here.
 

Is this finally the 'age of the smart dry washer'.........LOL.
 

To give some control a 10Amp Variable Transformer AC Voltage Regulator before the main transformer could be used.​

 

high voltage transformer is used for our HV power supply

input voltage: 300V (20-60Khz)

output voltage:DC 2KV~15KV

output Current: DC 0-10mA

rated power :100W

$27.00
 

How to Make 30kV High Voltage DC Power Supply with Flyback & Cockcroft-Walton Multiplier Tripler



How to make a high voltage DC generator/power supply using a flyback transformer and a Cockcroft-Walton voltage multiplier or 30kV tripler. This one generates up to 30 kilovolts with milliamps of current. I demonstrate it using sparking and by powering a lifter or ionocraft. It uses: - 220 ohm, 3 watt resistor - 27 ohm, 2 watt resistor - 4700 microfarad, 35 volt electrolytic capacitor - two 2N3055 power transistors - flyback transformer with no additional electronics attached to it - 30kV Cockcroft-Walton voltage multiplier, also known as a 30kV tripler I show how to power it using my homemade 24 volt power supply, a simple wall adapter and a laptop power supply. For a video showing how I fixed this power supply when it broke, watch this: http://youtu.be/Kb0WwsJgTMM For details about my homemade 24 volt power supply, go to: http://rimstar.org/equip/24v_pwr_supp... For my webpage about this high voltage power supply, go to: http://rimstar.org/equip/30kv_pwr_sup... If you want to make your own tripler/Cockcroft Walton voltage multiplier, see my webpage here as a starting point: http://rimstar.org/equip/negative_vol... For a flyback transformer without a built-in diode (the one for this power supply must not have a built-in diode) see here: http://www.ebay.com/sch/sis.html?_nkw... The Sanyo F 0241 listed there might be a good one, but I can't say for sure. WARNING: This power supply delivers a lethal amount of current, in the milliamps. It is not like a small homemade Van de Graaff generator whose current is in the microamps. Notice the precaution of using a grounded discharge stick in this video. Do not make this one unless you understand how to use it safely. Also watch: How to mount/attach transistor to heatsink (2N3055) http://youtu.be/hNRacVQRgBc Lifter Voltage/Current and Smoke/Aiflow Test Measurements http://youtu.be/LOGAaObsN4g How to Make High Voltage Capacitors - Homemade/DIY Capacitors http://youtu.be/MPD7skZ8OSo
 

This will help out. I like the control on the input voltage.

Nice to see the project all in a video,
 

Last edited:
Xenon or high-intensity discharge (HID) headlights have a ballast that typically are 9 – 18 VDC input and around 230000 volt output at about 35 watts. This should work however is dangerous if you come into contact and can be dangerous to life.
 

You can smelt too an article from 1958, very informative.

Additional pdf file, Electromigration

static.png

static2.png
 

Attachments

  • You-Can-Smelt-Too.pdf
    2.7 MB · Views: 66
Last edited:
It appears then that around 15,000 volts is a good place to start with.
 

If you google 'rotary triboelectric separator' you'll find some research papers and thesis from the Mining Engineering dept at the University of Kentucky. They are focused on coal but some it may apply to what you're working on. I know they also did research on a shaker table design that blew air across the table instead of water.
 

gold_miner said:
If you google 'rotary triboelectric separator' you'll find some research papers and thesis from the Mining Engineering dept at the University of Kentucky. They are focused on coal but some it may apply to what you're working on. I know they also did research on a shaker table design that blew air across the table instead of water.
Click to expand...
You are thinking like I do. I'm thinking of making a dry washer where the air is blown over the drop riffles. I'm calling it a 'supercharged dry washer'. There will be a bag catcher as well.

Thanks.
 

gold_miner said:
If you google 'rotary triboelectric separator' you'll find some research papers and thesis from the Mining Engineering dept at the University of Kentucky. They are focused on coal but some it may apply to what you're working on. I know they also did research on a shaker table design that blew air across the table instead of water.
Click to expand...
I did look here for information about the shaker table and found nothing.

https://www.engr.uky.edu/research-faculty/departments/mining-engineering

Is there a link for the information?
Thanks.>
 

Last edited:
Air Gravity Concentrating Tables on line information:

http://mine-engineer.com/mining/minproc/air-table.html

http://mine-engineer.com/mining/minproc/air-table2.htm

The mechanism is attached to the table, and it moves the table along the long axis a distance adjustable between ½" and 1" and then back to the starting position between 200 and 300 times per minute. This reciprocal movement is faster on the reverse stroke than it is on the forward stroke. This shaking movement helps transport the concentrates or heavy material to the concentrate end of the table. A very important operating variable of a shaking table is the tilt adjustment. Normally, the feed side is lower, and the concentrate end is higher on a air table, which creates an upward slope where the heavy material will ascend, while the light density material will not, and consequently, flow over the riffles. The tailing (low density) side is near level to lower than the feed side. Another important variable in air table operation is the volume of air, and this is typically adjusted by a series of valves, or plate type regulators, allowing more or less air to flow to the deck. It is important to have a uniform flow of air across the deck, to prevent "blow outs", which is why multiple air regulator points are provided for air tables. A comment on the art of operating gravity tables, is that the optimum operating settings must be obtained experimentally, by making minor adjustments to the air flow, end tilt, stroke length and frequency and the side tilt of the table. Generally speaking, the frequency and stroke relationship are similar to screens, short stroke, high frequency is better for fines (-80 mesh), while a shorter stroke and lower frequency is better for coarse material (1/8" to 80 mesh).

Feed is introduced to the feed box in a narrow size range. For air tables to function effectively, the feed needs to be in a narrow size range, usually with a ratio of 2.8:1, from the smallest particle to the largest particle. The maximum particle size is about 1/8" and the typical fine size is normally 60 mesh that can be separated on a air table. 60 mesh is 0.0098 inches. So, if 60 mesh material were to be separated, the feed size range would be from 0.027 inches, or about 25 mesh, to 60 mesh. In all gravity separations, a difference in specific gravity of the materials needs to be significant, at 1 or greater. I.e., a 2.2 SG material will usually separate from a 3.2 SG material. Air tables can also separate, somewhat, on particle shapes, also, as differing particle shapes react differently in the rising air columns. Generally, these will show up in the middlings (discharge between tailings and concentrate).

There has been very few successful applications of gold recovery, using air tables. Even though the difference in SG is great, the gold, during crushing, becomes flat and forms little aerodynamic wings, that tend to float across the riffles to the light density tailings side of the table. Air tables have been successful in many mineral separations, such as tungsten, fluorite, garnet and they work well in coal.
 

Since most crushed gold is very flat maybe air blowing over the top of the material will work the best. I will try shallow channels in rubber / plastic with a air blowing over the top.
 

You must log in or register to reply here.

just for fun where would you dig??

⬅️ Previous Thread

Whippet dry washer

Next Thread ➡️

Top Member Reactions

Users who are viewing this thread

Total: 3 (members: 0, guests: 3)
Simplex Metal Detector

Latest Discussions

Back
Top