Simple Filters for Simple Fire Systems

[TomC]

Is the inlet to your sock/towel filter at the bottom? If so, doesn’t the vacuum at the top tend to suck the sock closed and flat?..Would a fine wire cage on the inside to hold the shape make it more efficient? TomC

[Jeff]

Tom, the inlet is at the bottom The out let is on the top And yes the sock has a cage inside. I do not remember if this one is a wire cage or a PVC pipe with big holes drilled in it. I think I liked the fence wire cage better but so much time goes by I forget.

Edit: I mixed up my inlet and outlet.

[bsoutherland]

Jeff,
Is the small clear filter for catching big dust? Instead of cyclone? Interesting. A simple visible coarse filter followed by a fine sock filter. My wife sewed some filter socks for me from an old wool blanket.
I have used that kind of clear filter as a final/safety filter and wrap the screen with white fiberglass cloth to visually judge effectiveness of main filter.

How about 40 mesh screen followed by wool sock, followed by 40 micron safety screen?

[Jeff]

Hi Bruce. The final filter is the clear water filter, 30 micron. The course filter is the sock that is inside the the long red thin wall PVC pipe. Seems to work pretty much as is.

[bsoutherland]

OK, got it.

I was confused because you said that the inlet is on top and the picture shows the clear filter in the hose before going to the top inlet.

How many hours do you have on the 30 micron filter?

[Jeff]

How many hours do you have on the 30 micron filter?

I never kept track. I just run the stuff now a days. Don’t have to think about, just light the fire and kick the tires!

[Jeff]

was confused because you said that the inlet is on top and th

Bruce, I’m the one confused. I woke up this morning and it hit me that I had the inlet and outlet mixed up. Oops.

[trigaux]

Dave, Thierry,

Is there any other reason for a narrow vessel to perform better other than that a greater portion of the the fuel will be freshly added?

I am not able to answer this question. Koen and Aleksandr probably have explanations on this subject.
I suppose narrow reactors (like those of Koen and Aleksandr) realize a more complete reduction of CO2 and water, it generates a richer gas

Thierry

[trigaux]

Is there any other reason for a narrow vessel to perform better other than that a greater portion of the the fuel will be freshly added?
[/quote]

I am not able to answer this question. Koen and Aleksandr probably have explanations on this subject.
I suppose narrow reactors (like those of Koen and Aleksandr) realize a more complete reduction of CO2 and water, it generates a richer gas

Thierry

[k_vanlooken]

Hi Thierry,

There is indeed “some” influence between the diameter and length vs the amount of power to be generated.
size and position of the nozzle included.

The biggest role however, in making good charcoal gas, besides good fuel, is the filter setup ( the topic )

The less “drag” your “filter” creates, the more easy the system can “breathe” the more gas can be conveyed to your engine.

I will try to extract some data to compare from my research material and post it here.

[TroyMartz]

i will be running with 3 tiny cyclones (in parallel), like a Dyson vacuum cleaner, and fine-grade perlite as a final media filter. I like perlite because it has a massive surface area, won’t burn, can get wet, is washable, and you can burn off the particulates and reuse the stuff almost indefinitely… it’s also cheap…

Anyone else using perlite? I love it…

If the cyclones are operating at 90%, it should be a pretty good system.

[bsoutherland]

What do you think about a filter lid for a wide bodied reactor/hopper that has a layer of coarse perlite followed by fine perlite? A coarse screen to support the coarse perlite and a fine screen above and below the fine perlite. No cyclones or filter plumbing, just one tall column with a clean gas outlet at the top.

[Jeff]

For a plug style filter wall action can be an issue. For example a five gallon bucket filled with some kind of media. Inlet at one end and outlet at other. Gas is like electric it takes the path of least resistance. So, the gas will tend to fallow the walls of the bucket and somewhat skip the filter media. Not completely but some.

[BillSchiller]

I can’t help to think that that a charcoal filter would work well. Why wouldn’t it work? I envision a vertical pvc pipe or 2-3 in parallel sharing a condensate tank.One could attach a tee at the bottom so one can use couplers. A flush style screw cap on top so it could be easily emptied.

[bsoutherland]

Jeff,

Thanks for the wall action reminder. What if we glue wool blanket, window screen or foam rubber or something else to the walls? Are there other simple solutions for this phenomenon?

[Jeff]

Bruce, I think that would do the trick. Anything to break up the path along the wall. I remember reading something about that. The dirty filter media should tell the story.

[bsoutherland]

I was reading down through this old topic as I’m designing a new gasifier for Africa. This discussion went a little sideways about the difficulty starting up on previously run charcoal. Then I saw this screw in earth anchor at tractor supply.

I thought it might auger down to the nozzle in my MGB to lift old charcoal away and let fresh char fall into place.

After giving it a try, I made this modification:

[Bobmac]

Great find on a off the self item. That is going to work great for reconditioning the char bed and fluff it up with new char.
Bob

[Handy_Andy]

Clever use of materials. But the real question is,did it help ease the startup as hoped?

[k_vanlooken]

This is a great example of having a thought and finding the right tool for it… :+100: = * 100