Water bubbler - scruber

Well you make the same point I made when I asked the question because I love the oil bath in my old tractors. They work great for dust. But I figured since I have not built a gasificer I would just accept the word of those who have. LMAO. I guess that is devided into two camps now. I wonder if the oil gives more trouble with wood not charcoal. Just wondering if maybe the fileting needs are different? No idea on my part just collecting information for the time when I get my tractors and loads ballance enough I can afford the power hit to DOW one. Right now they are really all overloaded on gas.

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I have not seen you use oil bath filter with your charcoal gasifier?

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Hi Thierry,

Just look more carefully :wink:
The bottom of the drum on my tata…

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Hi Dan,

Part of my life is “rejecting” the words what others say…
Only what they “do” and can “show” …
I never follow what i have been told…
If i did that, i would still making fire with 2 stones…

The oilbath filter will collect dust and also condense some heavy tar period
The colder the filter, the more tar (if any present) will stick in the wire fiber…

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Saying this off hand, l wuld say the problem with oil bathing woodgas is water. All the condensated steam wuld soon build up in it, riseing the surface, putting more drag. Allso, mayonese might start to form. This oil contaminated water wuld be a biogazard.
Perhaps use a oil bath filter instead of the paperfilter in a gas reheat filter sistem? And allso (like Koen said) bennefit the carburated gas effect from it.

Hmm oil bathwith small amount of ethanol in it… Good for tar removal and carburation…

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I’m enjoying this discussion. I’ve been waiting for a good DOW conversation on filters like we had for charcoal nozzles. To Wayne’s point if you have the engine pulling a vacuum on the water chamber your “venturi” will just be a short circuit hole to suck unfiltered gas into the water chamber. The highest vacuum is on the engine side outlet not on the reactor side inlet.

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It was a rainy day today so l decided to go ahead with the scrubber.

Here it is!

And in action (engine running on petrol, a peace of glass instead of the hayfilter lid)

As you can see, it works! Pulls lots of aspirated water on top.

The drive was great. The venturi choke doesent seem to effect the pressure drop too much. I started with a 22mm choke, l think l wuld get by with a 20mm.
The water was indeed black after a short drive, but its too soon to say anything about efficiancy.

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Always fun to watch your progress reports.
Btw, have you been driving enough to say anything about how your new reduction design handles ash?

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Good discussion. I think more approaches and thinking on this issue can only be positive, success and failures all add to the body of knowledge.

Kristijan, brilliant concept and execution! The video is unequivocal proof. I agree that motors shouldn’t be considered disposable, I know I like mine to last. Conceptually I can agree with Steve U that for a first gasification attempt, that engine should be considered disposable.

I would like to hear data on how much vacuum this system adds, and compared to other filtration systems, and post scrubber tests for any particulate. (But I can’t imagine much getting past your scrubber).

I am sure we will have reports in time about how often the scrubber liquid needs to be cleaned, and disposal issues.

Settling followed by wick siphoning should be practical to periodically clean soot, tars and ash from the liquid, allowing re-use. Or how about a centrifuge?

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Jan,
Thank you!

On the reduction, all l can say is after 500km, so far so good.
Actualy, not to be cocky, but it seems it runs better each time. I think ash insullation accuulation on the right places might be the cause.

Garry,

Thank you too!

We have a saying, “luck is on the side of the brave”, so l kind of followed that, althug l agree on what you sayd.

Ha data will be hard. All l have to offer is subjective observations.

I was driveing well with the scrubber for the last 2 days, but the a/f ratio was set more to te rich side, indicateing bigger pressure drop. But l noticed a partialy dissconnected gas hose, leaking air in, so l have to make some more testing.
Other ghings seem to run quite well…

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Ok this is the sistem l currently have installed. So far, it all looks good. I abandoned the secondayry bubbler, too much pressure drop.

Now, the water has much less movement in the water pool. This means soot can settle down on the bottom over night, then not get disturbed at operation. Yesterday l took a look in and saw about 3mm thick sediment of fine soot on the bottom.

This scrubber allso seems to do a good job at demoisturiseing the gas. Kind of funny, drying the gas with water :wink:
l drain the water out of the cooler each day, yet still find a lot more water in the scrubber thain l put in.

ps. there is allso a thin film of tarry compounds on the surface of the water. It does catch tar, but to what extent is hard to say.

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Yes, if your fuel has 10% moisture, and, for example, if you convert half of it to H2 and O2, then you still have half of that water in the output gas stream. There’s even more to it, because there is always moisture in the air. That moisture also ends up in your scrubber if it’s not decomposed to HOH.
This is a very normal thing in my Chinese JXQ-10 gasifier. I have to watch the water level in the scrubber carefully on a day with high humidity. I can gain so much water then, that it upsets the pressure balance in the system on long runs. It’s similar to trying to check engine oil while the engine is running.

Pete Stanaitis

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Too high water level allso caused me some problems, exspecialy at idle.

Culd you describe your sistem a litle bit? Perhaps a picture or two?

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Hello KristijanL.
Go here and click on the picture with the green generator set in the center:
https://spaco.org/Woodgas/Woodgas.htm

Pete Stanaitis