Woodgasing for Multiple Engines and Flares

Hi All
A new member Jim LaPlant posted this a question over on the Premium side about using a large Cadillac vehicle sized WK woodgasifier to woodgas fuel supply a 4400 watt generator, his two cylinder bandsaw mill and a house hydronic heater.
Valid inquiry. Had it myself. Tried this some myself. I wanted to dump out my experiences, observations and equipment base information sources about attempting this.

First it is important to come to the firm understanding that a gasifer/producer does NOT supply fuel gas.
The gases flows MUST be pushed-forced out, or dragged-forced out through a flow restriction packed char bed and downstream of the reactor/producer on a filtering/cooling system.
Goona’ take physical power to do this. Normally we let the IC engine hard capable sucking do this flow making. This is really one of the prime reasons for engine power derating of shaft out power versus gasoline/propane/natural gas before even considering the lower woodgas fuel BTU’s, and different combustion pressure rise characteristics.
Woodstove, fireplace, open air woodfire your heated rising combustion gases are your flow pump. The fuel woods are laid/set loose and flow past capable. (Or; too tight and then real smoky!)

Want to multiple variable loaded engine and heat flare burner supply then you DO have to convert to a fuel gas SUPPLING system.
Ha! They do make off the shelf equipment to do just this.
Combustion Blowers
Draft Inducers
Combustion Power Venters
Always best to hippy, skipping past the university geek, and never used woo-woo patent stuff go directly to the actual in-use equipment informations.
Here is a site link way above small engine use needs that will familiarize you with the pressures/vacuum’s, material selection, staged booster types and power type inputs AND POWER NEEDS to handle the real world sucking, pumping and pressurizing of dirty nasties gasses:
Read completely through thier six Blowers & Gas Booster sections to get your info overview.
They will tell you when and where they will use 304SS, 316SS, Hastalloy, Inconel, coatings or just simple make thicker sacrifice materials and why.
This is for the guys on the Premium side now active materials testing for corrosive acetic, hot, wet, woodgas and tar vapors.

Now to a more practical affordable pushing/pulling flow making flow blower sources then search out the manufacturers names and products of:
Tjenlund; Nordyne; and Eclipse

What I’ve actually used has been Amtek Nautilair
If this link works you will see a picture of a guy looks just like me kicked back in front of a wood stove reading just like I do.
On these brands pay attention to power needs in amperges, voltages, and combustion gasses/temperature materials capabilities. You want to avoid the cheaper made in China boosters with plastic blower wheels if used on the HOT gasifier suction side. Even a blower on the air-in side can have gasifer heat driven self-pressurized woodgas backed flow exposure. Corrosion. Worse. On the next blower powering up if has exposed motor electric contact brushes then an ignition lite off KA-Booom WILL happan to you! You really want combustion rated equipment.

For variable supply woodgas delivering you will want to both blow and suck the gasifier with cut in and out powered boosters or variable speed controled the flow boosters.
Even the cheapest of these at $150 to a single Amtek Nautilair at ~$500 USD is going to be More than the combined SEVEN ganged up ~$20. each plactic bilge blowers Wayne Kieth now uses to blow and suck up his vehicle system to good using heat. Note: he ONLY uses these for cold gasifier heating up - NOT engine fuelgas supply power boosting.

System fuel gas SUPPLING now independent of the engine sucking you will have to flow blower power-up blow/suck contiously.
Only the Amtek has the 20,000 hour bearing rating with an internal variable speed brushless design. Real LOW wattage to operate at ~178 watts. But as a small single only then able to flow supply one small engine and one small flare.
Why you can see pictured multiple series, and parallel ganged up small blowers. This is for either a higher pressure draw or a greater flow rate capabilties. Three of these would be ~ONE horsepower equivalent to power. So your little IC engine sucking a woodgas system is having to use at least one shaft produced horsepower to do the system flow sucking. Vehicles this can be 10 and higher hoursepower to system fuel making/pulling in sucking.

You can see it get stacked up expensive in costs and input power needed to play the pressure fuel gas suppling game.

So much cheaper, and simpler, to just make a couple of different sized gasifiers for different ranges of engines needs and just then let the individual engine do the proportional flow making.
Making and supply “producer gas” for heating combustion was never easy, or power input free either.
Search up pictures of the the “Seattle Gasworks Park” and see the big powered blowers needed to producer make and to home pressure deliver the fuel gas.
Early on they steam engine powered these suction/pressurizing flow blowers. Later hydro-electric motor powered them. Other places powered their gasplant blowers with produced gas fueled engines or diesel fueled engines.

I’ve made my biggest woodgas Ka-Booms playing with split system woodgas making and woodgas pressure delivering.
Had my biggest carbon monoxide headaches, disorientation and dizziness pressurizing gasifier hearths, downstreams and to engine/flare woodgas suppling.
Every leak then no matter now small then not safe air-in sucking, but carbon monoxide out blowing sneeky. Producer gas WAS the suicide gas. Propane and supplied/delivered natural gas artificially mandated doped to be make you puke gases before asphyxiating.
Woodgas has no such safety build in.

#1 reason that I cannot recommend pressure suppling it in any way. An engine suction system is the hands down proven safest.
#2 reason I cannot recommend pressure supplying it is then common DYI simplicity is lost.

I think that the only way to really woodgas produce and SUPPLY flow to multiple variable loaded engines AND heat combustion burners is going to requires some electronics feed back controlling of the blowers and split gas out supply feeds.
DYI electronics controlling designing, fabricating and then later diagnose troubleshooting and repairing is a very small percent of the DYI woodgas user base.

So you fellows go ahead and kick this back and forth around all you desire. I’ll say nothing more here. Edit no one out.
Did teach me to move past intake pulsating single cylinder engines to multiple cylinder engines with their steadier, more even intake suction.

Steve Unruh

1 Like

Howdy Mr Steve,
Glad ya posted on this subject…
I’ve been wondering for a while now about Max’s Mixer and whether it might be suitable for this application… I think you have some experience with it?
Good to see ya goin to Argos!

Hey TerryL
Yes if by Max’s Mixer you mean the large diaphragm pressure differential “flow” sensing type I did make up three versions.
For actual engine mixer used; DJ with his duel single action “Mickey Mouse Ears” Volvo car version is the one with the most actual engine running experiences. He did not do these on his small engine projects as he says unnecessary. Woodgas has such a wide range of engine runnable A/F that for small stationary generators as he, ArvidO., and many other have show fine active mixture tuning is unnecessary. Pre-Set valve mixing just fine once past a starting up “choking”.
Ha! Of Course I had to try anyhow. Absolutely will not work on a pulsating intake single cylinder four stroke engine. Be even marginal with the intake pulsation’s on a twin four stroke engine down speeded to 2200 to 2600 RPM like I use.
Useable on three cylinder and above engines. DJ’s, Max’s were four cylinder engines.
The active “users” here I was involved with on these larger engines always drifted into engine exhaust O2 sensor active controls. Once at that level of electronic control dependency in place then mixture control is just another ElectronicControlUnit channel-out stepper controlled actuator motor. So my made up diaphragm assemblies were set aside and got tossed I am sure for silicon based controls.

I’d never thought until you ask of using them for flow blower motor controls.
Easy enough to set up as roller arm MicroSwitch activators. Plunger cam grinding on the movement rod.
Or throttle valving the inlet or outlet of a flow blower motor. Interesting that. Strangled then your blower wheel speed INCERASES and the power wattage DECREASES as you are then blower motor loading less. I find this works just as well as a blower motor speed controller. One of the supplier sites above talks about suppling this kind of flow controlling.
Making these diaphragms actuators for woodgas is tricky.
At our low pressures the housings need to be at last 6" to 8" (150mm to 200mm) to have any usable force produced. Housing have to be thick and rigid enough so movement is not lost in housing “tin canning” but all transfered to the actuator rod. Diaphragm needs to be center rigid stiffened to generate the greatest actuator rod movement. Still the flexible outer diphram edge wants to “bubble gum” and “balloon” limiting the center response movement. And then the actual mass and weight of the diaphragm center stiffener, plunger rod and attachment will affect response time.
Look at street gas control valves and pressure dropping regulators for the sizing needs. Housings if you could get them. Diaphragm material if you could get it. The best diaphragms would be outer edge pleated and stiff rings.
Duel sided double acting has to have the actuator shaft bellows sealed. I used a pleated bellows seal out of an oil bath clutched diesel forklift starter. Some motorcycle cable covers would work also. This has to be set at the system in use neutral point to minimize alcuator shaft affect. Wants to be a compression/pull spring. Why DJ went with two opposing single action diaphragm actuators.
Work past all of these, make it work, mistakes gives a great appreciation for the experience and knowledge in the old vacuum/mechanical controller designer-builders.
They weren’t so dumb.
Done again for woodgas I’d recommend starting with a min 10"-12" (25cm-30cm) diameter housings.

Steve Unruh

Hi Steve;
I agree with you on the dangers of pushing the gas thru. I came up with one way to run more than one small engine with a large gasifier that normally runs my 4 cyl. ford genny. Just make more gas than you need with your suction fan at the flare stack. Then just draw what you need from this flowing gas for one or more engines. There is some waste gas this way but it can be kept to a minimum with a reostat control by making just a little more gas than you need. Be careful of the unused gas for carbon monoxide poisoning. You can see me drawing what I need for my log splitter while letting excess go by. Dan C.
EDIT: Forgot to mention that the point I was making when I designed this setup for my splitter was to keep the reactor temps. high enough in a larger gasifier while running a smaller engine or two. This was to keep tars from forming because of the weak draw from the small engine.
- YouTube

Hey Dan,
Glad ya posted that link, I’ve mentioning it on the Friday night Hangout…
Ya saved me hunting it down!
Thanks for sharing.
Thats good stuff.

I was thinking Max’s mixer in suction mode, not so into pressure feeding anything gasified. I should have made that clear, not my greatest strength :slight_smile:
All the Best.

Good example of how to pull a gasifier, and push wood gas safely at the same time. Makes me want to try it.

Hey Dan, according to Steve U, your engine should benefit power wise by not having to waste power sucking on the gasifier. Do you see this happening with your generator setup?

Well to do this pull/push technique you will want long lived contstant duty capable SUCTION/blowers.
Plenty of these available AC powered.
Very hard to find low voltage DC powered.
Again this link for small engine suppling capable:
The Nautilair line has 24 and 12VDC models.
Expensive. Yes. But metal blower impeller, all metal housings up to an actual ~600F/316C intermittent and 400F/204C continuos capable. Brushless with 20,000 hour life rated ball bearings.
Once you stack up the prices of two 12vdc batteries and a HD 1500 watt DC to AC inverter for for an AC motor solution for a mobile or stand-alone then simpicty, even expensive, wins out in the long term.

DanC the way to handle the excessive gases production is to flare them off.
This gets tricky as when the engine is variable loaded for flare stabilty. Look at any older electro/mechanic oil furnace igniter systems as pilot-less systems. They self-sence burner head combustion tempeature and will repeat, repeat, re-spark to make a lite-off until re-heat is sensed. I have one of those also set back aside.
Ha! AC powered.

Steve Unruh

Steve, the link (www.ametecktip.com/index.php) does not work. But I will gladly add that I have used (and am using) Kirby suction blowers under the hood pushing woodgas into the engine. On my first rig, we would run the Kirby continuously (off an inverter) while driving. It was the only way to keep her running…
Thanks, JohnS

Thanks for the catch JohnS
I fixed my slurred “teck” (instead of old speak “tech”) in my link above to the proper new speak of of “tek” in their registered name.
Works now.
Filter Queens and Rainbows are also good suction vacuums to woodgas with too. Much quieter than a Kirby. ALL amp hogs.

Best Regards
Steve Unruh

I see you mentioned these blowers before and they are brushless. When I look on the ametektip site there are also ‘combustion fans’ but they don’t mention brushless. The blower fans are brushless. So I’m curious which category of fans on this site do you recommend? It appears to me the blower fans would adapt well.