Department of Energy slideshow (interesting)

[phil (admin)]

https://mfix.netl.doe.gov/workshop/CMFS-2014/multiPhase_topHat.pdf

[bbain]

A bunch of that is way above my paygrade, but they seem to be saying that for their particular application a Thien seperator is more efficient than a cyclone, but together they are more efficient then the individual components.

Interesting that their concern is the actual recovery of the particulate to keep their process going where we are interested in collecting the particulate to get rid of it.

[phil (admin)]

It would be interesting to hear any sort of presentation that went along with the visuals.  Or read anything that had been prepared.

It is hard to take away too much from the slides, but I did think the separation efficiency of the differing models was valuable.

[tomservo]

It looks to me more like a comparison between various exaggerated possible thien baffle setups. I expect the excessively tall shapes are due to materials on hand based on what it says. Looks like putting a helix at the top to guide the flow, with the blower inlet in the middle and an effective height of about 3x input diameter showed both high efficiency and low pressure drop. It doesn't show a bellmouth. If you look at the page titled "Final Design" you can come up with some ideas. I've finally got my hands on a barrel so this is timely indeed.

If I scale up the approximate ratios I see on the rendering, I come up with an 8" blower inlet, 21" separator diameter and 6" inlet with maybe 20" from the top of the inlet to the bottom of the separator. I'll try it. The helix will be a pain but I have some ideas.

I have no idea if it will work, though, he is clearly dealing with much higher velocities than we are: the lowest pressure drop was 2124 pascals = 8.5" water.

[tomservo]

Heh, so obviously I got right on this, but anyways, I spent some time today and made some progress.. I think all the parts are done except the barrel inlet, and I want to do that last, maybe out of sheet metal at work where we have a little brake. I cut the barrel in half, made plywood "rings" I put around the cut edges, so I can put it back together for now. I plan on putting either a bigger barrel or a brute or something under some day.

I found a piece of 8" PVC a few weeks ago, so I also made the collector - > blower pipe. I used my router to round the ends on the inside, as I don't have a bellmouth. At the blower end the rounded edges will meet up nicely with the inside of the impeller. There's a round lip on my impeller that will fit in the recess formed by the plywood rings.

I made a preliminary baffle with more 18mm birch ply. Haven't decided whether to mount it in the top half or bottom half of the barrel.

I also constructed a spiral ring out of some 1/8" hardboard, two pieces which will be glued in place (and together). It's made to have a tight fit on the PVC pipe and a reasonable fit on the barrel. It will be glued into the barrel with hot glue (and a heat gun to preheat the barrel).

The barrel top plywood piece is actually the circle I cut out from one of the barrel flanges, and the baffle is the other.

Specs of blower: 8" inlet, TEK355 BC airfoil impeller, 4.5HP motor. The unit draws 3HP worth of power once it's running. The impeller is supposed to flow ~1600CFM @ 9" so I think I'll have enough flow no matter what.  The separator will have a 6" inlet with an 8" outlet to the blower. I will be making an air straightener.

[phil (admin)]

Looking interesting, looking forward to more progress.

[tomservo]

I bet you thought it'd be another 6 months before the next update, but I am here to report:

Progress!

I made the vortex manipulator today, tack welded the center pieces together and it is installed. I put it about 1 1/2" from the inlet of the blower intake. It's an "X" shape but that was just the easy way out so I took it. It's already an 8" pipe.

The spiral is installed, and I did the fitting of the center to fit the pipe. I just stood above it and cut away until I could just sight down the outside of the pipe, all around. I have pictures of how I set it up, I put the blower upside down on top of the bottom barrel piece (to accomodate the motor) and then put the top barrel piece right side up on top of the intake pipe. I used 4 bottles of oil as stands to get the right height. The fitting took maybe 20 minutes with a die grinder.

All that's left is to align/fasten the barrel halves, cut the inlet hole and make a square to round adapter.

The blower is attached to the inlet tube with 4 1/4" bolts and t-nuts.

[tomservo]

Back from the dead again! Progress! I have built a stand out of angle iron - it's built over tall on purpose as I will get another barrel to make a full sized waste barrel later on.

I am working on the molded inlet, here are a couple of pics of the early shape. I am waiting on my local plumbing store to come up with a 6" PVC ("weeping tile") coupler to mold in at the business end. Overall outlet will be about 7.5x4". I'm using the 'lost foam' method described by another forum member. The outlet size is more or less tuned to be the same as the area provided by 6" DWV PVC.

The foam is some super ugly used 6" roofing insulation, polystyrene foam. It's got tar and crap all over it but mostly that cut away. I'll be coating the outside of the mold with something to smooth it down before fiberglassing as well as some plastic wrap or similar over the top to keep the polyester from melting the foam. Probably some drywall comp as I have a box of some old and it's easy enough to work with and inexpensive.

You can see the hoses I have been using for testing the static pressures.