Separator / Filter for Transferring Very Fine Powder

With very small particle size, cyclone separators are not ideal, but could help. There is a kit available as a pre-seperator for hobby woodworking shops. In this test, the Dust Deputy did best on fine dust. To work well, I'd guess that you might need more volume than a shop vac usually provides, but it is worth a try.

You can also get huge HEPA filters at woodworking supply places, one of which would allow you to transfer the 500 lbs. Then it could be wacked, reverse vacuumed, etc to clean it off. (Wear dust protection stuff.)

Go Big.....er

http://www.filtersales.com/pdf/Camfil_Farr_xh_absolute.pdf

Found this.....

http://www.dtic.mil/dtic/tr/fulltext/u2/402934.pdf

If you have to do this pretty often then I would look for a vac that has a water filter. The dry chemical collected wet will be much less of a mess to handle. Most filter though the water first before the HEPA filter. Also if possible I would look for one that has a tangent vac motor. The air through ones put all the dust though the the motor. Which can contaminate the brush and commutator. Reducing the vac motor life.

Usually only one 500 pound tank per year. Hard to justify too much money for an expensive vacuum that someone is going to ruin anyway. Thanks for the idea though.

I was going to suggest a small pulse jet filter, but once a year won't justify much. Unless you have someone with some time and ingenuity to fit one on your HEPA rig.

The video from K Fry offers three suggestions that seem to be exactly what I was looking for. If there is any custom fitting to be done, I'm the guy. Thanks.

Try a DIY water filter. 5 gal bucket with two holes the size of the vacuum hose. One to draw air at the top which will be attached to the vacuum. The other will have a pipe to drop below water level.

There are several closed loop systems that are made for this type of operation. You can transport powders great distances as well with these units. I am not sure why you need to do what your seeking to do but, given the lack of knowledge of your operation is hard to answer your question.

How far do you need to xport.

How often are you having to refill.

Try Whirlair Flow they make all kinds of xport systems for powders and bluk materials

It is a 500 pound dry powder fire extinguisher mounted on a large fire engine, used at an airport. We have three trucks with the 500 pound system, and near by we have a 3,000 pound system , also truck mounted. Currently we carry the 50 pound pails to the top of the truck, so distance is only fifteen feet with the hose setup we have now. If possible. I would like to let the vacuum, separator, and shipping pails stay at ground level. The top of the tank is about twelve feet from the ground. Normal procedure is a yearly demonstration for the FAA by one truck only. Any aircraft incident could require filling all three trucks. The 3,000 pound truck is only when needed, but drills require about 100 pounds per month.

I will look up Whirlair and see what they have

After Mt St Helens erupted the air was full of super fine dust.Most vehicles were disabled due to clogged air filters.There were a few, 4X4's however, that kept running with no problems.The local police stopped some of these vehicle to determine their secrets.

The owners, "Rednecks",by local standards,were using panty hose as a pre filter wrapped around outside of the regular air filters.

This back woods trick may work for you.Cheap and easy to try,anyway.

Thank you. The pour method is becoming a problem for the newer firefighters.

A local extinguisher service company sent me to Getz, but there is not much for the large systems we have. But, I will search the attached information for new ideas. Thanks again. Bob.

After reading both links, the Getz site offered nothing that was usable for our 500 &3,000 pound systems. But the Texas A&M report was enlightening. Although we do not refill the smaller extinguishers that they do, all of the dust and weather issues they face, are also present here. Our department has done training at T. A&M over the years. I will find out who here knows who there, and contact them.

Again thank you for an excellent post. Bob.

Um . . . am I missing something here.

You only do this once a year and the system you presently have allows you to transfer 250 lbs before the filters become clogged.

Why aren't you just replacing the filters after the first 250 lbs is transferred and finish the remaining 250 lbs with new, clean filters.

Because the boss does not want to have to change filters in the middle of the process.

I have seen industrial bag filters that have a blow-back function on a D/P switch.When the filter gets sufficiently blocked, it reverses flow and blows the filters off.Perhaps a second vacuum hooked discharge- to- discharge,into the primary vacuum, with the primary vacuum turned off, would clear the filters enough to finish the job.Or, use 2 vacuum cleaners.When one gets clogged, turn on the other one.While#2 is running, change filter on number 1 vacuum.

As it stands now, I have contacted an industrial vacuum company and they have suggested an improved vacuum combined with a filter/separator used in conjunction with the tank adaptor we purchased from the powder manufacturer. We are preparing for a Sept 12 demonstration. The issue I have with this system is the cost of the high powered vacuum, and the fact that the separator contains a filter that costs more than most "normal" shop vacs.

Thanks to the replies here, and some information gathered from Lee Woodworking, I have a few other options so far, and still have two leads to chase.

The water filter would work I'm sure I will have to give it some thought.

I am also looking at the adaptor that attaches to the tank. In the design built by the powder company, the inlet and outlet are close phisicly, with no baffeling. I am first going to try to extend the adaptor by means of a PVC extention for the adaptor and an extention for the powder inlet pipe. This should add 24 inches of seperation. Beyond that, I may try to install some baffeling to pull the powder out of suspention.

Again thanks to all that have brought idesa and products to the table. I will post developments as we go. Bob.

PS the site for Lee"s products are:

http://www.leevalley.com/US/wood/page.aspx?p=30282&cat=1.42401

I took a look at the Veritas® Cyclone Lid and my experience suggests the system will work well for wood chips, however most of the fine powder will stay in suspension and get conveyed into your vacuum. The volume of the can is not sufficient to slow the flow below the interstitial velocity of the powder.

Best of luck with your testing and I sincerely hope you can prove me wrong.