Test of resistance of cloths.
After cleaning cloths when driving on highways at 60kmh 150-200mm vp up to 500-750km driving.
(500km = 310miles)
Then the resistance increased by 65-75mm vp per 1000km.
Test of cascade scrubber 270mm vp 88.5% degree of purification in laboratory tests.
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Steve, I am of the same opinion, the blue flame is not my goal, as it burns quite “cold” (probably the combustion of CO to CO2, which you can see above the glowing coals), also in the engine it develops a low temperature and therefore low power. My goal is to produce a gas that burns with a bright (yellow) flame, this is a sign of hydrogen and methane, if you watch the combustion of propane or acetylene, they both burn with a yellow sooty flame, but when they are mixed with air beforehand, a light blue appears high temperature flame. Even wood gas behaves similarly, as an interesting fact I can say that I made a mixer out of a beer can that nicely mixed wood gas and air, so when the gasifier is heated I soon get a stable flame, but when the gasifier is at the “working” temperature, but this aluminum can melted in an instant.
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This is the kind of blue flame i get when i adjust the air mixture into the flare gas , filtration is wood chips and lambs wool .
Dave
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To put it quite simply, when Wayne Keith flares his gasifier he does it before the filter.
The unlit gas only looks like a slight haze. It’s hardly dirty. All he really has to do is coalesce moisture and some soot out.
The gasifier is what prevents the nasty nasty stuff from ever reaching the engine.
Edit: Another guy to see his results is Goran. He uses a hot filter. Recently checked his plumbing up at the engine and there’s barely a spec of carbon soot. But he also has a solidly designed gasifier, a hot filter won’t save you from a bad gasifier.
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Hi Thomas, as your thread is called Over engineering filtration, you should really look at electrostatic precipitators, complex, sensitive, but for a stationary setup it would work great, i believe.
These are known to separate almost all soot, tar mist, droplets, probably the most effective filters, the problem is designing them to easy clean, probably “batteries” of filter tubes, safety filters, valves that shift battery, if one gets clogged/shorted out.
A sensor that reads amps is probably a good thing.
And: what others said: a good gasifier, that is operated carefully is the most important thing.
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Just one consideration I have Thomas. You mentioned “other” gas-burning appliances, so I have a caution for you.
90% of residential gas-burning appliances would be found indoors. A gas leak, while dangerous from a flammability point of view, is easily found due to the mercaptan mixed with propane and natural gas.
Making your own gas will not contain the mercaptan, and the composition is a very high percentage of carbon monoxide. This incredibly deadly gas will go undetected should it leak uncombusted in the house. For that reason, I’ll give you the #1 safety rule of woodgas:
NO WOODGAS IN THE HOUSE!
(Also no gas in the vehicle interior, same principle.)
If you only intend to run this outdoors, well ventilated, then OK. But it bears repeating, if it prevents even one death or injury:
NO WOODGAS IN THE HOUSE!
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Exactly why I am not filtering yet, you have no idea how clean the gas comes from the gasifier. The better the gasifier, the less filtering is needed.
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lol, not to worry, i had no intention of pumping that much carbon monoxide into my house. be sure to not tell my dad but ive been working really hard at trying to get him able to get out and camp again. i think im close to getting him aa tracked wheelchair so that he will be able to get out in the woods again, and i plan on selling off some of my lumber on my land to fund a toy hauler thats nice and comfy so that he can rest anytime he needs to. hes getting up there in age and i dont want him to get into a rut of thinking he has to give up on enjoying life.
as a sort of unintentional bonus, theres a lot of “mini” appliances i can take with me that can be gas powered that i can setup in a little outside kitchen area and have some of the modern luxuries while camping.
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Electrostatic is the way I want it, but like every attempt only easy on youtube. No time yet for mounting the new electronics, hopefully this will do the job right.
If anyone has any idea how to build an electrostatic filter first time right, please thanks.
BTW, velocity is just pressure put into speed, no more no less. And if you can, I would have laminar flow as much as possible to have the lowest pressure drop and make up with extra surface if possible.
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That really is the number one rule where I dont have a solution yet.
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Hi Joep, i would keep an eye open for used welding fumes filters, there are some pretty effective electrostatic ones to be found.
Two would be great, to make a double filter-one operating, the other one cleaned.
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I never throw anything away, except…. And a few years later……
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Hello friends, do you consider that an oil bath filter unnecessarily filters gas impurities too finely?
I mean, filter until the gas is depleted! 
Thierry
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I have trouble beliving this truth be sayd… even if there is a sizeable quantity of longer chained hidrocarbons, if filtration does indeed remove them, where do they go? I sure never saw any and the law of thermodinamics say they cant just vanish.
As a mater of fact, l observe the oposite. On my BCS l have a motor oil soaked towel as a filter. After a few hours of work, the towel gets dry. Those are some real long chain hidrocarbons and the gas flow slowly evaporates them.
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So if the towel drys out the oil is being carried off into the engine and burned with no problems. This is the bath towel method you develop. This is what @JocundJake needs to use on his boat project.
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Had to. The filter is so close to the one cyl engine the pulsation shook off all the dust before it could form a cake. All the dust passed the towel. Its better now, the oily cake forms well.
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Okay thanks Kristijan, now I understand why you went from dry filter to a oiled filtering towel.
I will have the roof cooling tubes go down to the front under the bumper with your tube filter towel setup on the Subrau gasifer system. Using your idea just took 30 lbs. Or more off the my back bumper and put it up front on the Subrau. I need to find your thread on how you built that filter for your car. I had forgotten about it. So many great ideas that have been thought up on the DOW site.
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Maybe it is easier to run a liquid solvent fuel on shut down versus filtering the last 1% of tars during the full run time? Say methanol, ethanol, DME, acetone, etc?
What if you used titanium push rods…. Would they be strong enough to unstick tarred valves? If not titanium, maybe something else? May be overhead cams run by chains so valve actuation avoids long skinny rods? Would that be robust enough?
Not trying to derail the conversation re: electrostatic filtering but if the goal is tar tolerance maybe other methods are easier.
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When I am done running my gasifier for the day. I switch it over to gas for a few minutes to put some fuel through the engine valves ect. I think this is good. But not necessary on a gasifier shut down.
If you are not producing tar everything will be fine when you start it up cold.
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The main reason why any accidental tar is cleaned from the engine is because the engine is hot enough to keep it liquid and runny. When you switch to gasoline it’s simply rinsing it out. Maybe someone else could chime in but I doubt there’s much tar on the exhaust valves of an engine that got properly warmed up. I feel like it’s mostly the intake valves.
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