Need help understanding fluid bed principle

Ragnor

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Dec 7, 2015
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I did some quick searches on the internet and didnt get much useful information

Searching fluid bed and fluid+bed in the seach feature here yields 0 results for me.

Anyone know a good video, or drawings or detailed description that would help be to realize this concept?

I get the basic principle (I guess) but I would like to have a much more complete understanding of the forces in play that allow for this method of aggregate separation. As much as I do embrace the art of reinventing the wheel , sometimes that route is a bit more costly and time consuming than I would prefer.
 

Goodyguy

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The basic concept is.......

The continued introduction of fluid into a chamber filled with a medium of variable size and weight particles in order to achieve a saturation point so that gravity would allow the heavier/denser particles to settle through the viscosity while the lighter particles would continually be eliminated by washing over the top of the chamber.

In other words..... To create a fluid bed gold trap just introduce water into a container with just enough pressure to keep any sand and gravels fluidized to the point that heavies will settle to the bottom.

Important details....
The plumbing is key to the efficiency of the trap. You want the plumbing to fluidize the entire trap as evenly as possible thereby eliminating any dead zones where the material would not be fluidized, which would be the case if the fluidizing tubes were spaced too far apart from each other or the jets are too far from the sides of the trap, or if the jets are spaced too far apart from each other or the size of the jets themselves are too large or too small for the velocity of the water being introduced.

Too deep of a trap could cause a scenario whereby the plumbing could be overwhelmed by the weight of the material above the tubes causing too much back pressure against the fluidizing jets.

Yep it's a balancing act to achieve top efficiency. However even a poorly constructed unit will usually produce some gold recovery if it's not too far out of the ballpark.

Click here: http://www.bazookagoldtrap.com/content/BazookaInstructions.pdf for a complete diagram and more details


GG~
 

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arizau

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Found a couple of things that will help explain it to you. Just look at these and substitute a bazooka for the material delivery and processing equipment.
https://en.wikipedia.org/wiki/Fluidized_bed
https://en.wikipedia.org/wiki/Elutriation

Here are the search pages for further sites to look at.
https://www.google.com/webhp?source...=1&espv=2&ie=UTF-8#q=fluidized+bed+technology
https://www.google.com/webhp?source...S576US576&ion=1&espv=2&ie=UTF-8#q=elutriation

PS: I think it is possible to improve the bazooka if the tube introduced water is at or near to the bottom, as are the commercial production versions of fluidized bed technology, and my homemade one does just that. No tests yet so no proof.
 

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Ragnor

Ragnor

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Thanks, that gave me what I needed to start hashing on it.
 

SpecJet

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May 8, 2013
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Once you start to wrap your head around how fluid beds work, have a look at this study.
http://pubs.dggsalaskagov.us/webpubs/mirl/report_no/text/mirl_n76.pdf

It'll give you some insight into gold particle settling velocities.
Balancing the rising water velocity of the induced fluid with the settling velocity of gold particles is the key to capturing gold of a particular size/shape.

I'm looking for a Thesis I read some time ago that did a really good job of describing fluid beds as we use them.
If I manage to find it again, I'll post it here.
 

Goldwasher

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Found a couple of things that will help explain it to you. Just look at these and substitute a bazooka for the material delivery and processing equipment.
https://en.wikipedia.org/wiki/Fluidized_bed
https://en.wikipedia.org/wiki/Elutriation

Here are the search pages for further sites to look at.
https://www.google.com/webhp?source...=1&espv=2&ie=UTF-8#q=fluidized+bed+technology
https://www.google.com/webhp?source...S576US576&ion=1&espv=2&ie=UTF-8#q=elutriation

PS: I think it is possible to improve the bazooka if the tube introduced water is at or near to the bottom, as are the commercial production versions of fluidized bed technology, and my homemade one does just that. No tests yet so no proof.
If the holes in the bazooka tubes were any closer to the floor of the trap it wouldn't fluidize properly. Keep in mind what the end consumer gets at this point is not the first generation attempt. there has been a lot of testing to get it to the point its at.
 

arizau

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If the holes in the bazooka tubes were any closer to the floor of the trap it wouldn't fluidize properly. Keep in mind what the end consumer gets at this point is not the first generation attempt. there has been a lot of testing to get it to the point its at.

I should not have tagged it as "bazooka" but more appropriately as a new concept for a fluidized bed concentrator for stream use which is akin to a bazooka gold trap. I know you work for them and you/they make a fine and proven product.:icon_thumright:

Like I said, I have not tested mine so the jury is still out for my design but is more in line with conventional fluidized bed concentrators.
 

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SpecJet

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Like everything, the Bazooka is a compromise.
There are a lot of variables to contend with when trying to make a product that works well for most people in all the various conditions we find around the world.
And at a price point that most people find acceptable.
I think they hit the nail squarely on the head, so to speak.

There are a lot of ways to build a fluid bed, some better than others for a particular application.
 

SpecJet

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I've got a rotary drum fluid bed designed for a sub-dredge application that I'm dying to build.
With all the crap going on with California dredging, I don't think I'll ever get a chance to use it, so it sits.:BangHead:
 

motohed

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Hey SpecJet build it and I will run it . LOL
 

jcazgoldchaser

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Searching is pretty easy, but just "fluid bed" isn't much help because of all the industries that use a fluid bed either for separation or coating stuffs.

Beginner's class: Add prospecting or gold to fluid bed to narrow down the industry.
Intermediate class: Select the search engine's image or video selection. It's faster to scan information by image. Add the keyword "forum" to get discussions and less of technical papers.
Advanced class: Reduce the search to specific websites "site:". So "fluid bed site:www.treasurenet.com" only searches here.
 

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Ragnor

Ragnor

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I don't know man. I'm not sure if I should thank you or cuss you for that one.
but seriously, thanks, That is more than enough information on the subject :laughing7:
Once you start to wrap your head around how fluid beds work, have a look at this study.
http://pubs.dggsalaskagov.us/webpubs/mirl/report_no/text/mirl_n76.pdf

It'll give you some insight into gold particle settling velocities.
Balancing the rising water velocity of the induced fluid with the settling velocity of gold particles is the key to capturing gold of a particular size/shape.

I'm looking for a Thesis I read some time ago that did a really good job of describing fluid beds as we use them.
If I manage to find it again, I'll post it here.
 

Hoser John

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Just take a pan with black sand and plop a nice lil'ol' nugget-shake for 1 single second-viola gone-wet or dry between specific gravity and gravity the work is done for you-John
 

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