Hey guys, my name is Jason with Mt. Baker Mining & Metals.
Today I wanted to do a quick video on our Spiral Classifier and Dewatering Screw.
This is actually a really pretty versatile piece of equipment.
It's designed to take the tailings of off the Shaker Table and the larger material will
settle down and get augered and dewatered and only the fine material will go into the
tailings pond and turn into tailings.
Let me walk you through a few features of the screw and then we will take a look at
how it works.
So we place our Spiral Classifier right at the discharge of the Shaker Table, it takes
the number 4 material off of the Shaker Table and into this settling pond in the Spiral
Classifier.
The way the Spiral Classifier works is the size of the settling pond will determine the
size of the material that comes out into the tailings pond.
I always equate it to a pebble in a teacup you can flush out with just a little bit of
water but a pebble in a swimming pool, you can never flush it out of the bottom of the
swimming pool.
It's the size of your retention pond which is going to determine the size that goes down
into the tailings and that's regulated by these three different ports.
Right now it's set on the uppermost port which allows for the settling basin to be the largest,
largest volume and only the finest material will come out, the lower you set it the smaller
the settling basin will be and the larger material will come out.
Roughly speaking the lowest port down here discharges about 100 mesh minus, this is about
200 to 250, and this is 300 to 400 and smaller and that will depend on the feed size as well.
So the large particle size material falls down through the settling basin here and makes
a pile on the bottom and then gets augered out by the screw and as it augers out it,
it augers it up and out of the basin and then the water runs back down so the material is
effectively dewatered.
It augers it all the way up and into either a pile, or a bin that we have here and one
of the big advantages for a lot of our customers is, their mining in areas where they don't
have a lot of water and so they have to recirculate a lot of their water or over and over again
and one of the main uses of this pieces of equipment is to actually just dewater the
tailings, their not necessarily going to take them and re-run them through the system but
they don't want to have them go into their tailings pond and fill it up cause that water
is very valuable to them, so they auger them out, dewater them and that allows for a lot
more reciculation of their water and their tailings pond doesn't fill up with rock.
This screw turns about 10 RPMs, so it goes really really slow and the flights are a quarter
inch material and we put holes in them so the water can run down more easily, there's
about a half inch to three quarter inch gap between the spiral flights and the trough
on the Spiral Classifier and that allows for a sandbed to build on the bottom of the trough
and it keeps the wear on the trough to a very minimum, so the sand is working over a sandbed
rather than right on the steel.
A lot of people ask how long the flights will last, we've had this in our system for a couple
months now, we've run several tons of material out of it and you can see the paints not even
worn off of the flights yet.
So the wear on the machine is very very little and these flights will last a long long time.
If you come down to the end here you can see one of the things about our Spiral Classifier,
we keep the bearing outside the slurry, the bearing is completely separate from the water,
the shaft penetrates the basin here and that way you don't have any grease in the water
but you also don't have your bearing getting slurry and grit in the bearing and wearing
out the bearing so the bearing is completely removed from the high wear area.
So this is the discharge side of the screw and the material augers up the trough, there's
a hole cut in the trough here with a drip lip and the material is augered up and falls
out the hole and falls into this bin, it can be a bin, it can be a supersack, it can be
a pile but I wanted to show you the dewatered material and the size, this is anywhere from
probably 20 up to 30, 40, 50 mesh is most what you can see here.
And Its nice, it's dewatered, it's either ready to be disposed of or if there is still
appreciable values in here you can run it back through the system to grind it finer
and that's one of the ways a lot of our customers say I need 100 or 200 or 300 mesh grind size,
Spiral Classifier will auger the larger material up out of the Ball Mill or out of the Hammer
Mill that can then be re-run through the system to get the desired grind size and only the
finest two or three hundred mesh material will go out to the tailings pond.
So here's the material that I dug out of the bottom of our tailings pond and as you can
see it's extremely fine material, you really can't even feel the grains in your hand and
so it's somewhere between that 325 mesh and smaller.
We've sold these machines for Spiral Classifiers, dewatering screws, and Screw Conveyors, the
current version is 16 feet long and it will do up to about 5 tons an hour.
I hope you enjoyed the video, please let us know if you have any questions and thanks
for watching!
We will see you on the next one.