Author Topic: Wood gas.  (Read 15045 times)


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    • Flint Hills Diesel
Re: Wood gas.
« Reply #15 on: January 26, 2006, 05:12:53 PM »
Would this drive off light fractions as vapor, leaving heavy stuff behind? (like asphalt is left when cracking petroleum)
If so, what could you do with those leftovers? Would they pose the same disposal problems as glycerol which is left behind after turning vegoil into biodiesel?


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,

A country boy can survive - Hank Williams Jr.


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Re: Wood gas.
« Reply #16 on: January 26, 2006, 10:32:50 PM »
  The cam collar and cover on the left side of the block could be replaced with a cam and an end cover from a twin Lister. Then you could set the cam timing for your auxilliary fuel supply to the intake manifold. If you ran a fuel tube down the manifold you could release the fuel into the airsteam right near the valve seat. By using an injector pump with a low pressure 'nozzle', you could introduce viscous fuels without (excessive) precipitation in the intake manifold? The governor could also control it.
  Anyway, the cam could push a small air piston compressor to run the Babington atomizer, or any other timed event for 'special fuel'.
Scott E
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