Leitinger wood gasifier

Kristijan, be careful my friend, refuel only with a cold Gasifier, would hate to see anything happen to you or your love ones. Gas fumes can ignite from just smoldering ash.
Bob

Bob, l realy apreciate the concern. Yes, this is not my favorite thing to do (mostly becouse of the smoke) but l dont realy have much options. I only have a range of about max 30miles on one hopper. But this small hopper allso doesent hold much gas, so if it does ignite (and l light it with a lighter sometimes to kill the smoke when refueling in more public areas) it just burns like a camp fire. The hopper holds just about 5 gal of wood and is only 10" high.

But l did a stupid mistake once, trying to blow off the smoke with my mouth to see how much wood l have left, my moustaches got a haircut :smile:

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I have only gas up my truck three time sense it has gone back on wood gasification driving, and third time was just the other day. My routine is to go to the gas station with the gasifier cold. GAS UP. Now Iā€™m ready, after leaving the the Fueling station to light up the gasifier. It is the only safe way to do it. You only use a little bit of gas getting to the station to refuel. I always keep a 1/4 gas in my fuel tank and do not let it get any lower than that before filling it up.
Bob

Haha l think we have a missunderstanding here. I thod we are talking about refueling a gasifier :smile:

Refueling gasoline is of corse a nother thing. I fill mi petrol tank at home with canisters.

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Ha, Ha, Ha, that is so funny. You had me going there, my mistake. Duh, the laugh is on me. Reread it a gain, lol. Refueling (wood)
Bob.

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I drove with my kiln dryed hornbeam/beech chunks for the first time today. Althugh the chunks were not 100% dry yet, l wuld estimate at least 20% moisture content, the overall performance was improved over 4 year old air dry oak/chestnut/cherry chunks l used till now.
Torque was better, better turndown ratio and for the first time since l DOW the chevy, l culd ldle on 100% wood for on a traffic light and driveof without stumbleing!

Beech/polewood is considered premium firewood here. It burns steadyer andd longer in a fireplace, but l wonder what is risponible for the difference l am seeing here? Oak and beech have about the same caloric value so is the difference in charcoal perhaps?

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Hi Kristijan,

Yes, the behavior of the fuel, from chunks to charcoal and the way this charcoal can react due to its density ( less dense/more reaction surface )

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This is exactly what puzzles me, beech gives the densest charcoal of all wood growing here (exept plum, this was premium charcoal for forge welding). Ill hsve to look in the charbed to see if the shape of charcoal has changed.

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Char, preheat, insulation - I think anything that will keep the temp above that magic 650C in the reduction will help. Itā€™s all about heat.
Been driving for some time now below freezing and itā€™s obvious the gasifier needs longer warm up time before it can handle ideling.

Hi Kristijan,

I double checked, beech does have other behavior, different from oak and cherryā€¦
apparently it has to do with the fiber lenght and the cell structure ( whatever they mean ) and beech has another burning behavior as well ( more nice flame compared with the dense oak.
Also the kind of beech could play a roleā€¦

anyhow, the good news is, you prooved that things can be done, either way, and that changing fuel does have influence on the carā€™s engine behavior.

Kristijan, JO, why not build a cooler rack, next to the hopper, where the walls are heating up the next batch to be used in the gasifier hopper ? you can use the condense liquid to drip on the outside cooling tubes as well to ad to the cooling effect for cooling the gas below ambient ?
( imagine a basket inside a coil / heat exchanger )

Reading comments from another topic, slipped char in a WK, gives a great idea:
1: using a WK to produce char and energy ( running a generator )
2: using a Gilmore style with the char from the WK, and the condensate, to drive a smaller set, if needed, or even a smaller carā€¦
Combining WK and GGā€¦ unbeatableā€¦

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I would call that an Imbert. TomC

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Most of this effect you are seeing is the Rate-Of-Energy release from the one wood speices type to the other.
Rate-of-energy release is not the fuels energy density as measured by weight or volume.

A motor fuel gasifier/generator needs a higher energy release/conversion than a woodheating stove.

To ā€œadd more fuelā€ to the discussion fire . . . I have found that my Douglas Fir conifer woods vary a lot in rates of energy release from sapwood, heartwood, tops-woods, limb-woods portions.
Even though a low weight density wood - just need to use 2X more of it! Great energy.
Marvelous low, low ash wood. Easy grating needs.
The bad-for-fireplace tendency of Douglas Fir to pop and spark from the sap/pitchā€™s gassing out just adds more energy release in a gasifier.
Douglas Fir is also a low acid wood. Except for the thick matured bark, used as a leather tanning base. So. Do not gasiffy the bark chunks.Better as a pathways mud mulch topping anyway.

My point is ANY wood local to you can be made into a motor fuel gasifier input stock.
Design for its good; and bad characteristics.
High mineral ash content wood? Better use a higher flow velocity system with a command-active grate to make the ash march on through.
High acid wood? Use acid-proof metals. These are different than stainless. Read VesaMā€™s book for recommendations.
High sap/pitchwood? Follow the leads of those using pinewoods exclusively.

Regards
Steve Unruh

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Kristijan, donā€™t forget that you just cleaned the gasifier out. The clean gas filter could be helping out too.
Bob

I think l have found the reason for my power increase. The day l filled up the gasifier with kiln dryed beech l allso mixed in few chunks of charcoal in that were planed to be used in a experiment on ā€œwinter grade fuelā€. It wasnt much, maybe 10% by volume so l didnt realy give it much attention. Culd it be the reason? I think its likely.
So to clarify what l hawe in mind as ā€œwinter woodā€.
The idea is to score a perfect ratio of carbon to water so that the carbon cracks all the steam producet, that wuld normaly collect in the cooling rails while still makeing hydrogen rich gas and not melt the hearth. This was done before in ww2, a hybrid charcoal/wood gasifier, but l found no info on performance.
This morning l filled up the gasifier with a mix of charcoal and beech chunks at a ratio of af about 50/50 by volume. This is a refference ratio and l will move from there.
The performance? In one word: great. Turndown ratio and idleing were greatly improved, but the engine seem to run better at lower rpm. Infact, l usualy reech my top speed in 4th gear and then shift to 5 to maintain that speed, but today was different. I only got to 80kmh in 4th, then shifted and went up to 90kmh.
I think this is due to slower (less H2) gas, this indicates to much charcoal was mixed with wood. So, 25/75 ratio is next to test.
A nother absorvation is a MUCH cooler gasifier/cooling rail. The hopper barely got warm, so this allso means there is not much offgas at idleing after a hard pull.

Ill see how much water will collect in my condense catcher later when it all cools down.

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ā€¦and a light whisper was heard from a white, frozen landscape up north:
ā€œā€¦hopper condensationā€¦ā€

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Perhaps this cold, north whisper culd be more specific? :wink:

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Reading about your charcoal adding.
Weā€™re already producing pure charcoal, donā€™t we? Collecting the hopper moisture should have the same effect as adding charcoal in a non-monorator, right?

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Yes, you are right. My problem is eaven with the fan in the alubox l cant cool the hopper enough to condebse any water. It just cools it enough to reduce offgasing a bit. Allso, it has very litle surface. I havent got much time these days to experiment with the ā€œWK condensing pipesā€ style condensor, so this is my tempirary solution.

You have a condensing hopper but still get condense in the cooling rails right?

Yes, I do collect water later on. Maybe 1/4 to 1/2 the hopper amount. I guess I could use additional hopper condensation.
Please report your results. Itā€™ll be interesting to see how close to zero water you can get.

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Hi Kristijan,

i have some more cents to trow inā€¦

First cent: You have more ashes then ā€œnormal/otherā€ gasifiersā€¦
That means: more C is converted into C+O ( CO)
because if no O present ( From H2O , O2, or even better from CO2 ) then the char will slip thruā€¦ ashes will be formed when C is completely burnt.
Now, simple testing: hook up your gasifier , at a autotest station, to the exhaust measuring device and check for your CO2 levelā€¦ ( testing your gas, not your exhaustā€¦ :grin: )

Second cent: Water or moister in the gas: if it comes from H2 level, then a simple test with steel wool, will indicate the acid level, hence water coming from the Hydrogen formed and reformed.
More reforming, more fast the corrosion will take placeā€¦ )
With reforming, i mean reacting after the hot zone from the reduction, to form small % CH4, CO2 and H2O

Can you play with the airflow from your two layers of nozzles ? then try to increase the flow at the lower onesā€¦ or even better, ad another nozzle, pointing upwarts thru your grate, directly in your char bedā€¦

The cooler gas cooling system can also indicate a hotter burn / better conversion , less CO2 passing your char bedā€¦ a better balanced reduction zoneā€¦ = much better gas overallā€¦

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