Discuss/Detail out THE PEGASUS UNIT

Hi, Don!
2.9.2017

The reference you put forward describes fuel moisture, moisture in the gas is another thing!

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What temp is needed for gas?

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Hi,Don!
2.9.2017

Only reaching a dry status; after a good cooler the gas is 100% wet (damp, steamy) and cannot be put through a paper filter, which will ruin it straight away!

So, a few degrees above cooler output temp will do, a bit more makes it safer.
10–20 degrees above cooler output temperature is OK.

Then after the paper filter the temp may go down again, but keeping it still above dew point is avoiding problems at the mixer.

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So Max explanation has finally clicked in my head ( I think ).
Air or gas at a certain temperature and pressure will hold a certain amount of moisture, in solution, if you will. So by cooling it, we will condense out and drain away much moisture. Then when heating again above that temp, I will have less moister than the maximum it will hold, we will call it “dry” because at that temp and pressure it will not condense out even though there is in fact still moisture in it.
I’m imagining it as a sponge. freshly pulled from a bucket, water will easily drip from it. Once dryed some by squeezing or heat, it will not drip, even though it still contains some water.
Have I got this right?

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Hi, Andy!
2.9.2017

A very good similarity! Quite right! Now perhaps a preheat and warm kept paperfilter start to make sens?

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Andy good explanation! On my next build l plan to do something similar, only change is l will not use paper for filter media and l will filter prior to condensing, with gas temperature higher of water boiling point. Then its coolong, condensing, and mildly reheating right before the engine to feed the motor dry gas.

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Page 81, Fig 13, comes closest to the Simplefire

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Hi JO,

The picture/schematic with hopper condensation= on page 96, fig 22

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Page 104, fig 35, is close to my work…

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For the die hard’s, not the readers but those who prefer schematics instead of words… start after page 114… lick your fingers…

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@ Steve Unruh,
thanks for sharing this, indeed a must read book…

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Fellows this now AdminHidden (thanks ChrisKY) so-called post by me was a trashing-hack-attack.
No ME.
Not me cursing and bad-names calling.

Ha! Ha! Welcome to my world since ~2008. BenP’s world. Jim Masons world too. Anyone who would step on the toes of the current cultures lock-steps. “ALL Carbons are ba-a-a-ad! All Carbons users are planet killing, pee-loot-ers!!”
My newest wear about hat is black. Custom made hat. Says: “Free The Carbons!” You know like; Free Tibet. Free Willie; the killer whale.
Sadly I could not get them to make me up the shirt that would one side say: “No Carbons Should be Allowed to Escape, Free!!” The other side say: "ALL Carbons Should be Enchained, Locked-Up to two Oxygen’s!
tree-farmer Steve Unruh

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Hi All.I cannot speak to the best gas temp into the carburetor/mixer. I will defer to MaxG’s learned wisdom on this. When MaxG expressed that Dutch John on his MicroGasifier works had benefited from collaboration, one area WAS on gas cooling/dryind/dehumidifing . . . then engine exhaust reheating for a lower apparent relative humidity.
MUST DO for a final paper filter. ALSO you must heat the incoming air too so it will not re-cool the gas back down below to dew point!!

I personally fall strongly in the camp if just letting the engine eat gas moisture’s and soot’s. The prices that has - for system simplification - are those I am willing to pay.
tree-farmer Steve unruh

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A contraversal and provocatory shirt that wuld be :slight_smile: but a true one. People (politics) blame the relatively harmless CO2 for global warming just to distract the eyes of the masses from the real crimes that happen in terms of poisoning the earth. Sad.

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I feel a new button coming on soon! :grin:

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One correction, and one addendum from my comments yesterday.
J.O. I think now that the Fig 52 system does indeed have “two grates”. Stupid me. BenP’s unique three link grate activator does a ~15-20 degree back and forth movement. Like a kitchen hand cake flour sifter.
The pins could indeed stick up into arc-slots through a floor plate.
Why? I do not know. Advantages? None that I can see. A, have-to-try, to learn thing.

My add-comment is about GaryG’s works learned and shared.
His use now of sheeps wool blanketing for final filtering.
Sheeps wool fibers are actually hollow with a shingled outer walls. They absorb much moisture’s and oils. They will then just by gravity 90% drain out. The remaining moisture fiber wall surfaces clinging is much lower energy evaporated away.
Sheeps wool has one of the highest temperature resistances of all natural fibers.
And IT IS a grow-your-own, sustainable!!

Go soak an open cell square of modern foam. Squeeze it out. THREE days now trying to salvage dog beds foams from our recently gone-on cancer dog. Still not dry.
And MaxG has pointed out from hard learned experiences that foam for filters once moisture and soots laden blows gas-flow bubbles. These bubbles pop. Passing on what you were trying to filter out in the first place.

GaryG, I could kiss you, man
Steve Unruh

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Hard to find a bigger sheep wool fan here, from sox to shirts, winter to summer, thats the material l love to wear. Never cold, never hot. I took great care when l was about 12 years old, learning the art of makeing woven sox and clothes for the day my grandgrandmother will not be able to suply me with them. But, l must say, l question wools performance in woodgas filtration.
Yes, as a “hay filter” hay substitute, but not as a “paper” or “cloth” filter style filtration.
A hayfilter plays on the card of vast surface area. Presumeing the soot particles/droplets will sooner or later hit a wet grass blade, glueing to it. And if it doesent hit it?
Since all the effects of wool Steve had destcibed above, yes, wool is a perfect material for a hayfilter media. Drains water the same way it drains sweat.
I have alway been more in to “ziher” (sure) things. Not alowing any particles to pass. But its a hell of a jurney to make it happen, efficiantly and DIY.
My venturi scrubber DID catch all the soot. But like the “bubbling effect” Steve mentioned above on the foam filter, well, its eaven worse in a scrubber.
A scrubber with a final cyclone(s) to drive out the sooty droplets? Maybee… but for now, l think l will stick to fabric/towel filters.

Edit: one more positive thing about a wool “hay” filter media. Once used and saturated with soot, one culd compost it. Wool makes great rich compost.

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Yes sheep’s wool is defiantly for a “wet” filtering system.
VesaM in his book shows he has used both hot/dry and wet filtering systems.
Dutch John has used both hot/dry and wet - his hot Volvo system hot/dry versus the other smaller, as wet-washing.
Their HOT/dry were both nomex fabic/gore-tex coated, made up tubes assemlies.
O.K. When they were personally using.
Both relate experiences of hot-filter soot-lit-off, burn down fires, when others using.
I had two industrial hot-box bag-house filter fires myself. Aluminum/magnesium and iron/steel oxides dusts from the steel shot-blaster process makes what self-oxidizing compound?!
Soot fires at least could be oxygen deprived.
Regards
Steve Unruh

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Been using a wet paper filter for about three years with no problem. Maybe it only works with a single cylinder engine. Maybe a paper water filter is more course. Verified at Argos for two years.

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Jeff, culd you explani a bit more? Is it real paper filter or a sintetic substitute? How is it with filter cleaning?

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