Can pyrolysis oil be re-gasified to fuel a gas engine?

Hello Ken.

This whole pyrolisys oil isnt quite clear to me. Is there a reason why you want to go trugh the trouble with it when runing a stationary engine straight from a producer on wood chip fuel is well understood and countlessly prooven?


Hi Ken, it is good to have another west coast member wanting to do some gasification for running practical machinery like a water pump for irrigation of your orchard.
Keep it simple is one of the main keys to success. Here on this site there are many gasification builds that have done this. Look around at the many builts Charcoal being the simplest and then the wood gasifier builds. The cool thing is they both work. It is just the type of fuel in the pyrolysis stage that is different and that makes the gasifier complexity different.


Hi thank You for each of you comments and questions. I will try to answer some of your questions and give some more reasons why I am trying to use pyrolysis oil to run an engine.
One reason for going the pyrolysis oil direction is wood chunkers are not really available but wood chippers and grinders are very available. The first PTO chipper I bought made a very small 1/4 in. chip that is the right size for a pyrolysis oil reactor.
Another reason is my irrigation pump engines uses around 100 gal. of diesel fuel a day which is about the same as 2000 Lbs. of wood. That is a lot of wood to chunk with a saw! Also my pump engines are sized to the load and are not able to have the 25% to 30% loss in power. This is the reason I am trying to make a higher BTU gas using pyrolysis oil. One of my pump engines is a propane engine that I sized to be able to run on natural gas; so if I can make a gas that has about the same BTU as natural gas then I can run that engine.

20 years ago I was trying to make a higher BTU gas by making charcoal in a retort I built. I caught the gasses in a tank and when I burned them a few days later the gas started to burn as a light blue flame typical of wood gas then it changed to a heavy orange flame. ( methane?) I also made a black liquid that I later learned was pyrolysis oil.

The idea of putting the pyrolysis oil in the air intake of the gasifier would work.
Ken S.


First of all, there is no need to make chunks for a gasifier. Countless wood chip sistems exist.

Pyrolisys oil or tar is the nasty thing we all try to avoid geting in an engine. Haveing anything to do with it is risky.

Im afraid adding the oil to the gasifiers air intake will not make more potent gas thain a wood gasifier does. Because then it becomes just a more complicated wood gasifier.
Think of a wood gasifier like this. It consists of a charcoal gasifier (charbed) and a charcoal kiln (hopper) where wood chunks or chips break down to charcoal and oils prior to being combusted.

If power is the problem, then the solution is not being a purist. Runing hybrid will solve your problem. If you run 75% woodgas 25% petrol mix the power drop will be minimal.


Sounds like pretty big heap of wood. Are you sure your almonds produce enough wood to satisfy the investment into gasification? No matter of that, I agree with @KristijanL , that hybrid or dualfuel would be the best choice for you.


ChuckW turned us onto some info I think you might be able to use.


Thank you for the explanations, KenS.
So, your 100 gallons of fuel oil a day is for days you irrigate.
And that is one day a week for each section of trees? Correct?
How many days a week must you operate the pumping?
How many irrigation days a productive season must you irrigate operate?

I think KamilK was correct you can not possibly have enough self generated tree pruning/thinning/culling to annually supply your needs.

Using wood-for-power any system that throws away 25%-35% of the energy potential will be in a deep dark energy hole.
O.K. if you own a timber lot watching overgrowths and weather damaged fall and rot on the ground.
Some here love charcoaling. O.K. . . . (only using the white chicken breast, so’s special breeding hybrid breast makers. Saddest chicken we ever raised)
Your pyrolysis oil is only a possible 10-20% of refining down whole raw wood.
So, is the charcoal portion sold for a side income stream? A few come here to the DOW where that is their primary concern.
And they come asking the reverse. What can be done with the wastes off-gases and tars?
And some fryer oils diesel drop-in substitutes have come here asking how to gasify their accumulating barrels of heavy glycerin’s contaminated with methanol. Geez Dude. IF it has a fuel value why did you not focus on the using it up in the power making engine directly??

Most here are trying to direct use all of the wood’s energies, as directly as possible. So wastes and fractional utilizable thinking is not in our pursuits views.
Only interesting are DIY integrated systems that can evolved to 70% cycle full use efficiency. My bulk in-house wood stove sets this standard.

No offences intended. Just explaining the responses you will get.
Steve Unruh


Sounds to me like a hybrid diesel or diesel-electric system with wood-gas as a range extender to lessen overall fuel cost. Like Patrick Johnson. Build the whole thing on a skid or trailer structure. :cowboy_hat_face:

Ken, If you can build a refinery for pyrolysis oil, you can certainly build a wood chunker. Several proven formulas exist that could even be partially automated. maybe start a sawmill side business and have lots of scraps to use for fuel.


Do you shell the almonds? I’m not familiar with the shell. My almonds come in plastic bags, but I am familiar with burning cherry pits and they burn super hot. I believe many other pits and shells have the same BTU value. If almonds shells are the same it seems like an Ideal fuel source.


I can’t add much technical help but will add a caution. When I got into gasification (for a Fischer Tropsch project) in '08, I worked with a couple of chemists. One of them gave me some pyrolysis oils to “play with” as I’m in the industrial chemical business. He cautioned me that not only did it stink to high heaven, it contained lots of really toxic components.

Be careful handling the oils!


Yeah, its preety much what gives ciggaretes their hazard to health…

Tod, have you shared your experiances wih the FTS reaction here?


Hi. to answer the question if I have enough wood to run pump through out the irrigation season? The answer is yes! The irrigation pumps run 3 to 5 days a week April through October, less at the beginning and end of the season. I use around 5,000 gal. of diesel fuel and 10,000 gal. of propane per year. On the wood supply side; I sell 20 cord of fire wood per year and then the pruning’s that I chip, 25 to 30 tons per year. Also I am 200 acres surrounded by 1000’s of acres of almond orchards. Some of the pruning’s are ground up and left in the orchards which is good but a lot is pushed into piles and burned.
I am realizing the direction I need to go is a gasifier that is designed to use wood chips and continue to use some diesel or propane so there is not much power loss as Kristijan L. suggested.
Can you give me a link to wood chip gasifier plans?
Thanks for all the suggestions and questions.


Hello Ken, I am almost a beginner in the world of wood gas, but let me express my opinion on your situation:
-5000l of oil = 50000 kWh of energy
-10000 gall of propane (38000 l) = 250000 kWh of energy

so together you use 300000 kWh of energy, if we say that the efficiency of the motors is 30% you actually need 90000 kWh of energy to drive the pumps

-if we take 30,000 kg of dry wood = 120,000 kWh of energy, which would at best produce 30,000 kwh of propulsion energy, …

so I can easily conclude that you only have a third of the energy needed in wood, but even that is already a good proportion.
How powerful are your engines? Have you perhaps considered using electric motors for propulsion if your location allows?


Hey Ken,
With that level of power use, you would have a reasonable payback interval with a commercial offering.
Doubtful an R&D project is what you want when the pumps really must be working.
Quite a few offering out there for chips to electric power, but buyer beware.
Here is one western company with quite a few installed and running plants at the scale you are looking at, using a fuel you seem to have:

Don’t know much about them except through the testimonials.
They seem to be using parallel, hopperless, downdraft gasifiers to scale to the desired output.


Hi Tone he said 5,000 US gallons of diesel used. Not liters.
So that energy used line would need to multiply by 3.8


The translator translated it into liters, I apologize Steve, …
This makes the numbers even more unfavorable, with wood representing only a fifth of the energy, but even that is something. On this consumption, I would first study the pumps themselves, at what height the water is pumped and in what area of its characteristics the pump operates, there can be big savings, or energy losses, …
Otto engine produces 10kWh of working energy on the consumed 8-10 kg of wood and loses 40-50% of power.
Diesel with the addition of wood gas produces 10kWh per used 1l of oil and 4-5kg of wood and loses about 20-30% of power.
Please correct me if I made a mistake … :thinking:


These calculations are made at recent prices for diesel. Suppose the prices radically rose or supplies became limited. Prognostication? I’m not smart enough for that.

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Yup, you are a commercial grower. So I would suggest a ‘turn key’ setup. There are some around. I’m not selling anything here but one commercial gasifier maker would be Community Power Corporation, Englewood, Colorado


I was more involved on the gasification side than the Fischer Tropsch research. The group I was working with was commercializing some technology from a university. They had a nanotech angle to the catalyst but that’s all I know.


Sorry for the late reply
To answer the question directly, you technically don’t need to. These guys who are located in cali, actually have a patented way to take the condensate from the char making process and in one step turn it into a usable fuel. It is based on work at Uni of Georgia.

I have not much insight on the process, they have facilities in china and like indonesia.

Second, I just read a paper that said you could irrigate a bit less during the hot months without crop loss.

I know almonds use quite a bit of water so you may be already using the method.

I would probably look at putting a shipping container or two at the top of the property, then use a solar power pump to fill them up with water, and use it to feed a drip irrigation system. The new soil monitoring stuff is starting to look pretty decent for row crops. I would assume the same for orchard crops, but you can zone the areas and only water if they need it.

Certainly you can use woodgas, woodchips or even convert to charcoal for fuel for the generators. If I had that much usable wood product, I would be calling tolero to see if you can’t license like a mobile unit or something. You get the fuel, and you will get a bunch of biochar, and probably lots of minerals that you can reapply to your trees.

The other thing -I- would look at is the biological activity in the soil itself, which is my personal latest kick. Mychrozial fungi can actually invade a tree root, and they trade nutrients and water for carbon (they also like biochar) , they kind of act like root extensions except fungus excretes acids that break down minerals. THEY ALSO can excrete natural fungicides to help prevent some tree diseases. I am only mentioning it because I know there is a fairly high rate of fungicides in some orchards which end up killing the mycorrhizae fungus and beneficial bacteria.

Then there are nematodes that can kill a number of pests in the ground especially larvae that can help you out as well and reduce the need for the pesticides. Some of the packs with the mycorrhizae have some bacteria like the brasilia’s whatever that gets in a plant and produces nitrogen. It is worth testing because just have the mycorrhizae hold water in the root zone is going to reduce irrigation costs, and I am guessing it will also help hold rain water and let that soak in better rather then run off.

I wouldn’t go totally overboard for 200 acres but you can get mixes and test it out on a few trees. They actually say the noticeable difference in years of extreme types of weather like drought or heavy rains so it may not be a huge difference especially the first couple of years.

take it for what it is worth, which is just stuff you may or may not be aware of that may help you or it may not. i read all the organic techniques like that. some you might be able to use, and others are impractical at a larger scales and almost ALL changes seem cost prohibitive even if they will pay for themselves down the road.

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