Author Topic: Wood gas.  (Read 14627 times)

n2toh

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Wood gas.
« on: January 12, 2006, 04:27:54 AM »
Has anyone tried fueling their lister type with wood gas?
About 60 years is all it takes to make science fiction a reality.

Doug

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Re: Wood gas.
« Reply #1 on: January 12, 2006, 07:51:36 PM »
I've read a little about the subject, I don't think a precup inject engine will work well and you would need to reduce the compression ratio to about 15:1 (hard starting). Maybe a GM 90 electric start in dual fuel would be better. With a spark plug conversion and compression ratio change a GM 90 might work better than a converted gas engine...

Doug

Tom

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Re: Wood gas.
« Reply #2 on: January 12, 2006, 08:28:54 PM »
You might be able to use wood gas to supplement the diesel similar to LP injection. I have a file with the Mother Earth plans if you want them.
Tom
2004 Ashwamegh 6/1 #217 - ST5 just over 3k hours.

Doug

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Re: Wood gas.
« Reply #3 on: January 13, 2006, 12:12:05 AM »
Good Idea, now we need a place to save files...

Doug

SHIPCHIEF

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Re: Wood gas.
« Reply #4 on: January 14, 2006, 05:49:40 AM »
Wood gas?
Are you talking about Producer Gas? Like the civillian world used during WWII when all the combatant nations were using all the petroleum? Except in the US which had gas rationing?
I've been web searching Producer Gas, it's fun! Imagine running your engine on wood chips!
http://listserv.repp.org/pipermail/gasification/1999-November/003773.html
This link refers to Listers modified for Producer Gas.
http://www.woodgas.com/History.htm
This one has some history.
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

n2toh

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Re: Wood gas.
« Reply #5 on: January 14, 2006, 06:37:54 AM »
It goes by many names, and my intention was a duel fuel setup.

The only reason I mentioned it was for those of us who can't easily get waste fuels.
About 60 years is all it takes to make science fiction a reality.

SHIPCHIEF

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Re: Wood gas.
« Reply #6 on: January 14, 2006, 07:30:11 AM »
I was always worried that it would be hard to get started. I mean, if you were starting without any power to operate a fan to suck thru the gas generator, and also to roll the engine over to get the gas into the engine?
Also building the gas generator to use the local available fuel source, like wood chips or sawdust from a nearby mill?
This is an area of engineering that was well established before petroleum fuels took over the market. Fairbank Morse built whole powerplants to run on producer gas. The problem is finding anyone alive locally that can help. There are old engineering books, and now third world web forums that are helpful, but I have not followed thru yet because I'm still setting up my "Engine Room", plus now 'desanding' my engine.
I used to want to build a steam engine, but this is more interesting, and potentially alot more efficient.
I bought an oversize Listeroid 25/2 because the power output on producer gas is fairly low, and I still wanted enough to run a house / farmette.
I have plans in my little engineering binder for conversion to spark plugs, lowered compression, and LPG, natural gas or Producer gas carburators.... Don't know how far this will go... :-\
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

n2toh

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Re: Wood gas.
« Reply #7 on: January 14, 2006, 10:47:03 AM »
Funny you mention steam, The acrcile I was reading that inspired this thread started off with steam, and ended up saying that wood gas fed into a diesel is better and safer then steam.
About 60 years is all it takes to make science fiction a reality.

Tom

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Re: Wood gas.
« Reply #8 on: January 14, 2006, 07:41:18 PM »
Do you have an on-line link to the article???
Tom
2004 Ashwamegh 6/1 #217 - ST5 just over 3k hours.

dwkdnvr

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Re: Wood gas.
« Reply #9 on: January 15, 2006, 12:15:13 AM »

I'm quite interested in wood/producer gas in a Listeroid. From what I can determine, it should be a pretty good fit. IMHO the best approach is a multi-fuel arrangement where you use diesel (or hopefully SVO) as the ignition fuel and augment this with some level of producer gas drawn in via the air intake. The SVO option is particularly interesting, as the waste heat from the gasifier can pre-heat the SVO. It seems you can use producer gas to cut conventional fuel consumption down to maybe 1/3 of normal.  It's not clear to me whether the compression ratio would have to be reduced for a multifuel setup.

One challenge seems to be that a 6/1 would need a very small gasifier - most of the discussion around the net seems to be around how to make machines more appropriate to auto engine scale devices - 20kW+.  You'd almost certainly need a mechanically produced fuel - wood chips or maybe shredded material compressed into pellets. or briquettes. Even 'small' branches/logs would be too big for a 3-5 HP unit.  This fits my fuel source reasonably well I think - I have lots of pinon/juniper on the property, and I think that shredding the branches and needles would be a good briquette source if mixed in with a binder (waste paper for example)

The other main challenge is cleaning/scrubbing the gas to remove any particulate matter, although the Listeriods might be slightly more tolerant than modern high-rpm engines.



kpgv

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Re: Wood gas.
« Reply #10 on: January 15, 2006, 05:30:50 AM »
Hi,
My worry about introducing "fuel" into the intake "air" on a diesel is there is always the risk of an uncontrollable runaway.
That said, more alternate, and CHEAP fueling options are ;D ;D ;D.
Can one stop the fuel flow from one of those "generators" easily, and safely quickly ???

Kevin

SHIPCHIEF

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Re: Wood gas.
« Reply #11 on: January 15, 2006, 10:22:39 AM »
Easy;
The governor control arm could be connected to the carb throttle as well as the fuel injector.
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

Doug

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Re: Wood gas.
« Reply #12 on: January 23, 2006, 07:20:00 PM »
Hey dwkdnvr :

If you havent already look up the Gassification Archive.
And shreded wood products even compressed won't work they have to chunks or blocks in the 1 to 2 inch range with a moister content below 30%

However the Kaile charcole gassifier deveoloped in Sweden durring the war might be a better choice if you don't mind building you own retorte to process the wood.

Doug

I read and tinkered for several months with a small copy of the Fluidyne pioneer class before I abandoned the idea of generating my own hydro with wood.

dwkdnvr

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Re: Wood gas.
« Reply #13 on: January 26, 2006, 04:30:41 PM »
Hey dwkdnvr :

If you havent already look up the Gassification Archive.
Yes, I have spent a fair bit of time there, and on the more 'consumer grade' Yahoo group. I'm currently working through a few books I picked up from Tom Reed's site as well, which help to pull things together

Quote
And shreded wood products even compressed won't work they have to chunks or blocks in the 1 to 2 inch range with a moister content below 30%

Well, that's not really consistent with what I've found so far - at least in theory. From what I can tell, virtually any wood product can be gasified, but the challenging aspects are
a) gasifier design is critically dependent on feedstock, and vice-versa. If a gasifier is designed for wood blocks, it won't work on shredded material for example
b) getting it to run predictably without bridging
c) ash content (this is one place I'd be worried about pine needles)
d) getting a reliable continuous fuel feed.

This is in addition to the question of whether it's even possible to actually create compressed briquettes out of the type of stuff I have around with reasonable effort. Certainly I can' t see loose shredded material being a viable fuel - pyrolisis would happen too fast and unpredictably, and I'd imagine that ash and bridging would be a real problem.

Quote
Doug

I read and tinkered for several months with a small copy of the Fluidyne pioneer class before I abandoned the idea of generating my own hydro with wood.

Well, it is pretty obvious to me that if one is looking for a full-time/production grade solution for power, woodgas is not the answer. Far too finickey to be a 'start and forget' solution at the small scale. For thermal I think it has promise, but since our cabin is in southern Colorado we have solar thermal opportunities out the wazoo, and so just don't have that much in the way of thermal needs.  However, since my application is for a weekend cabin,  I may be able to make use of something like a '2 hour batch run' setup to recharge batteries etc, and it's the only way I can see to get power out of the 1 resource I have for 'free'.
 Even so, I'm beginning to wonder whether simply trying to compost all the wood waste and generate decent soil to try to grow a small ~1/4 acre patch of sunflowers might not be a better approach - run them through an oil press for maybe 25-50 gallons of SVO per year. Seems like a lot of work (and water, which is very scarce) for maybe $100 of fuel payoff, though.

Mr Lister

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Re: Wood gas.
« Reply #14 on: January 26, 2006, 04:52:59 PM »
List,

An idea occurred that might be possible - thermal distillation of veg oil waste.

Just as wood can be pyrolysed into wood-gas, but suffers from the sticky tars, which the valve gear hates, is it possible to pyrolyse waste oil and fat?

Any pan full of oil will start smoking when heated, and with sufficient air supply will ignite and burn your kitchen down.

What if all the yucky gloop in the bottom of the waste veg oil can was heated in a heavy duty tank and a small amount of it thermally vapourised using some sort of glowing electrical heating element, about 500 watts, driven from say a 12V alternator.  It would produce just enough heat to vaporise the fuel at the rate the engine was using it.   About 0.58 US gallons per hour for an 8hp engine.

If you exclude the air it will not ignite in the vapourising vessel, and should be cold enough not to pre-ignite when mixed with the inlet air.

This vapourised oily gloop can then be drawn into the engine via the air intake, to offset the amount of oil injected.

I guess it's like a vapourising carburettor,  but for oil rather than gasoline?

One other idea is to use a Babington type nozzle, to atomise the pre-heated gloop and blow it in with the airstream.  If the nozzle is driven from an air pump synchronised with the induction cycle, it will only atomise the oil when the intake valve is open.

The governer control arm can be used to control the auxiliary fuel supply so that it can be adjusted when the correct rpm are reached.  It would also allow the engine to be shut down for stopping and to prevent run-away.

This method might allow other waste oils, used tranny fluid and other less than idea fuels to be used - without having to put them through the injector.



Any ideas,


Ken