Trommel Designs

IMAUDIGGER

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In a situation where the oversized rocks are being cleaned sufficiently, but the fines need further washed (think dirty clay material) does a separate smaller reverse spiral drum for the fines have any advantage over just using a longer scrubber drum?

You don't see the separate reverse spiral drum used very often..so I'm wondering if it has its place or not. Obviously it's more moving parts but less wear and tear on the scrubber drum.

I'm kind of thinking if the heavier clay isn't broke up well enough in the main scrubber, it will just have the tendency to ball up in the spiral.

I'm not talking about a micro trommel (no shovel or 5 gal buckets involved).
 

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Clay Diggins

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A trommel is a type of autogenous mill. In autogenic milling the larger pieces of ore help break down the smaller pieces of ore.

It's sort of like a ball mill with rocks instead of steel balls doing the work. Surprisingly autogenous milling is most effective at abrading the smaller particles rather than working by impact. You want the material to mostly slide and tumble only slightly. That will clean off the smaller rocks and break down the clays much more effectively than removing the larger rock and processing your smalls separately.

Autogenous milling is used extensively in the mineral processing industry and is a well understood process, Leave the larger rock in the trommel as long as you can without overloading to get your most effective recovery. :thumbsup:

Heavy Pans
 

Bonaro

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Without adding a second trommel, you can add a minor reverse helix inside your existing trommel. This would work the rocks toward the feed end and retain them in the trommel longer, allowing them to clean the fines

MULTOTEC-TROMMEL-SCREENS-PIC-02.jpg
 

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IMAUDIGGER

IMAUDIGGER

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I can get it to fully wash and break up the material by feeding it slower and holding the material back longer in the scrubber drum..problem is, I want to increase the production rate.

I think the scrubber drum would have to be longer.
 

arizau

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Seems to me that the pitch of the drum effects the drum load and the retention time. Maybe changing the pitch is part of your solution(?).
 

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IMAUDIGGER

IMAUDIGGER

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A prewash shaker deck before the trommel should speed things up :icon_thumright:



GG~

Yup, but that's outside the budget and scope.

Conveyors would be awesome too.

I was just wondering if the smaller separate reverse spiral drum is something people are using to increase the washing of the fines. Seems advantageous due to the ability to adjust the RPM independently and less time between blurbs of material.
 

N-Lionberger

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Spotted this guy years ago in a yard in Hayfork, thought it was a neat set up, looked like a shaker hopper to big trommel to smaller trommel.

IMG_2222h.JPG
 

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