Pyrolysis Oil - Free fuel from wood / plastic

[farmerjohn]

Hey guys,

Thought I would share my quick experiment with Pyrolysis Oil
https://photos.app.goo.gl/D2TRXR9GM3PEmr83A

I made a crude reactor just to test the concept..  Made about a liter of oil from a few handfuls of wood pellets

The listeroid ran on it for almost an hour

This spring I plan to scale things up..  I have access to a machine shop with a CNC machine.  I'm building a screw auger reactor out of stainless

We live on 10 acres of land with TONS of trees/brush..  My goal is to be 100% energy independent before the end of the year.

Right now I collect WVO but its becoming harder and harder to source for free

Next tests will be figuring out a good catalyst to improve the quality of the output.  As-is the oil is pretty acidic and will wear out the engine.  I may rebuild the fuel pump and injector with stainless and maybe get the piston coated..  But improving the oil will be better long term.

It is a carbon neutral process

I'll share more in a few months when I get back to it.  But so far its showing promise

John

[dkmc]

Interesting. I have a few questions. How long time wise did it take to make the 1 liter of oil?
Also, how is the 'reactor' powered, and how much fuel was consumed making the liter of oil?
And how much energy and time would be spent converting your woods into pellets?
Not to mention the cost of the pelletizer, unless you have one already?

[farmerjohn]

dkmc,

It only took about 15 mins or less..  plus I hacked that thing together in about 20 mins from scraps laying around

In the pictures there is a propane burner that it is sitting on..  cannot see the flame in the photos but I heated it up to about 550C

There is no need to use pellets - I just happened to have some and it was convenient.  Wood chips would be fine

When running full scale it would first start off with electric resistance coils to get things started..  then switch to the gas produced by the process (It becomes self sufficient)

The process generates roughly 1/3 condensible gas, 1/3 un-condensible gases (mainly carbon monoxide, hydrogen, CO2) and 1/3 biochar (Carbon black)
The biochar can be fed back to plants (making the process carbon negative) or burned as a source of fuel for heating, etc..  its basically charcoal powder that comes out

You basically heat up any carbon based material in the absence of oxygen and the heat will break up the carbon bonds into more volatile compounds

There are a ton of scientific papers out there that go over the process in detail..  Plastic is MUCH easier than wood..  but I have a lifetime supply of free wood

If you plant hybrid poplar trees - you can coppice them every 4 years right down to the stump and they will re-grow again in 4 years and continue to do so for about 25 years.  Plant 4 rows of them and harvest one each year and you are set for life

I have some parts machined for it already over at .the machine shop..  I'll take some pictures when I am there next week

I'm building a ground source heat pump from scratch right now so wont be working on the pyrolysis till that is done

Let me know if you have more questions..  happy to go into more detail and inspire others to follow suit.  Can easily become energy independent even if you only have limited space.  Look into hybrid poplars used in the paper industry

John

[dkmc]

Very interesting. Will follow this thread for updates.

[snowman18]

What you have is wood tar, your Lister will run on it but it's going to coke up the engine real quick.

Wood tar, liquid obtained as one of the products of the carbonization, or destructive distillation, of wood. There are two types: hardwood tars, derived from such woods as oak and beech; and resinous tars, derived from pine wood, particularly from resinous stumps and roots.

https://en.wikipedia.org/wiki/Wood_gas

Wood gas is a syngas fuel which can be used as a fuel for furnaces, stoves and vehicles in place of gasoline, diesel or other fuels.

During the production process biomass or other carbon-containing materials are gasified within the oxygen-limited environment of a wood gas generator to produce hydrogen and carbon monoxide.

These gases can then be burnt as a fuel within an oxygen rich environment to produce carbon dioxide, water and heat. In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons.

[farmerjohn]

Snowman,

You are way off base here..  its not simple wood tars..  there are over 300 compounds in the condensible gases - some more volatile than the rest.   With the proper catalyst - the oil is closer to diesel
Have you ran pyrolysis oil in an engine before??  Aside from the acidic properties - which can be solved with the proper catalyst - there are zero coking issues.   

The main benefit is the ease of storage compared to wood gas...    Wood gas is an on demand process that requires a ton of attention to keep it going whereas pyrolysis oil is near the same as diesel and can be stored long term and used on demand the same as any other liquid fuel - in a tank

In my case - I have an abundance of free wood at my disposal and excess solar power during the summer months to process the oil

Wood gas does not scale.. its a fallacy..   I can make thousands of liters of oil from wood in the summer and burn it all winter on demand

Read the research papers...  google wood pyrolysis..  the science is clear

Nobody has time to monitor a wood gas plant...   its a pain in the ass..  the process of converting wood to oil is self sufficient and wood is in an abundance (for me)..  spend a few days making a few thousand liters of oil and then rest easy till winter

[farmerjohn]

Aside from the acidic properties - which can be solved with the proper catalyst - there are zero coking issues.   

I don't know why you would have a problem with acidity. Acid can only exist in water and if the fuel is properly cooked and captured, all moisture should have already been driven off before the actual phase change reaction happens.
At very least, running the output through the super heater should allow the output to be light enough for the moisture to stratify in the output collection vessel and be avoided.

Glort - you are correct..  without a catalyst the bio-oil produced from wood contains near 20-30% water which cannot be easily driven off..  mainly because of the other volatile compounds that you would lose in distillation, etc..   its doable but not necessary..  the water actually aides in the combustion process

Even if you started with 100% dry wood - the process converts some of the wood into hydrogen and oxygen which then combine to create water vapor

The setup that I am considering will use fractional condensation of the gases in 3 -4 steps..  each providing a different quality of oil and water content

On my office PC - I have a huge list of scientific research papers on the subject..   I'll make a list of those on Monday and post here

Wood is far more difficult than plastic or tires, etc...  I am interested in wood because I have ample supply on my own land..  I am not dependant on some outside source

[farmerjohn]

Hey guys,

Thought I would share my quick experiment with Pyrolysis Oil
https://photos.app.goo.gl/D2TRXR9GM3PEmr83A

I have done a bit of cracking so please take the following comments as a helpful heads up. I have not done wood, I did Veg and engine oil but I believe much of it is the same in practice. I have done charcoal in a semi sealed vessel though.

There is no need to use pellets - I just happened to have some and it was convenient.  Wood chips would be fine

If you can heat the vessel the wood is in evenly ( or not so evenly)  You could use chunks as well. Smaller Pieces would give more surface area and may make the process quicker but you can easily cook 4"  branches and splits and more as well.  Just mmight take a bit longer but not necessarily more fuel/ Input.

When running full scale it would first start off with electric resistance coils to get things started..  then switch to the gas produced by the process (It becomes self sufficient)

That gas/smoke is uncondensed Fuel. by burning that you are reducing the amount of final product you get. You are also investing electrical energy which I assume you are paying for one way or the other when you could just use the free wood supply you have.
While I understand your test setup was just that, it was also highly inefficient. That smoke is raw product. I have seen other vids on YT with crude and ineffective condensers with smoke billowing out and a few drips of liquid and I just cringe. I would suggest 95% of what is coming out the cook vessel is condensible fuel and letting it blow away as smoke or feeding it back into the fire is like having a hole in your fuel tank and dropping fuel along the road as you go. 

One would be far wiser to just fuel the reaction with other raw material ( I used crappy oil and dropped out solids in my playing around)  in your case wood and keep the energy invested in the precess to making product and maximising the output from each batch.
On that, If you were to use something as I did, a stainless steel Keg with a welded on piece of pipe and screw on end cap, I think that would be much easier and more effective than a screw auger arrangement.  To me that invites the presence of oxygen which will give you ash not product. The other major problem I see with the screw feed method is you will have a continual output of water vapor that will condense back into your  fuel output.  It may settle out as a layer but I'd suggest far better to drive off all the vapor first and have the rest of your output completely dry.
 If you got a litre of output from that little test devise, you are going to get a very worthwhile amount out of something the size of a keg.
If you upsized to something the size of a 200L drum, maybe an old water heater or Gas tank....  One batch  may be enough to keep you going some time.

I would also suggest using a decent size output line on your cook vessel so there is no chance of blockage or pressure build-up in the cooking vessel. You will also need to get it hot enough to completely phase change all the tars etc to ash to ensure the process is complete and the vessel is clean. 

You don't need a super powerful condenser but something is good. An oil vehicle oil cooler brazed with hard copper line with a fan blowing through it is a great approach.  I found that putting the end of the output tube in the collection vessel and bubbling it up through the distillate does a great job of getting the most yield and very little product is lost through smoke. For the first run you can just put a bit of diesel in the output container so the end of the output tube is submerged.  I let the initial steam go and then when I was getting smoke I started collecting the output.

I think your output going by the colour and my own mucking around is also very raw and as said, would not be good for the engine. It looks like it may have also gelled when it cooled down. This is what mine did the first time which indicated to me I hadn't actually Cracked the oil.
What I did was make a super heater and ran the output through that before  it went to the condenser.  The technical sounding super heater was nothing more than running the output line back under the boiler in my case, down through the fire which made the line run red hot and then back out to the condensor and collection vessel. This properly cracks the output by separating it into fractional  components.
You can then take them off separately to different fractions like petrol or diesel like our  absent resident Genius ED does here ( Look up his posts on this) or just recombine it all together.  Mine came out just like a Diesel petrol mix in that you could put it in a saucer and it would light like petrol but wouldn't burn all together unless you heated it up like diesel.

It did come out very clear ( although somewhat black/ brown) and a thin liquid.  I believe just taking it off the initial cook leaves a lot of impurities which are burned off or changed in the superheating process. Whatever takes place, I can tell you the output is vastly cleaner, less viscous and much improved. With wood I would suggest it would either burn off or refine the tars.

DO NOT SoLder anything with the output, Braze it or use screw/ flare fittings only.  Solder won't last 2 Minutes once you get the thing up to proper temp.

The process generates roughly 1/3 condensible gas, 1/3 un-condensible gases (mainly carbon monoxide, hydrogen, CO2) and 1/3 biochar (Carbon black)

I don't believe that is accurate.  I would suggest the great majority of the gasses are all condesable as  fuel. You just have to actually condense them properly by cooling them sufficiently. Any smoke to me after the initial moisture being driven off IS recoverable fuel. Having the output come out as in your test is very wasteful and any escaping vapor is lost product. Co2, Hydrogen etc are all invisible gasses so you may see them bubbling through the distilled output but if you are seeing smoke, that's lost yield. I found the bubbling method to be VERY effective even with minimal output cooling.  Be careful of any connections you make though with the output tube. what  running through it is effectively live steam and that cam reach VERY high temperatures far beyond the materials phase change temp.

You basically heat up any carbon based material in the absence of oxygen and the heat will break up the carbon bonds into more volatile compounds

And when you re condense the output, you can get a clean, liquid fuel that is more volatile than what you started out with.  In my observations, the hotter you can get at least the vapours from what you are cooking, the better. Running mine through a length of pipe ( about 30CM was enough) of glowing red hot gave Vastly superior results than just catching the vapours that basicly boiled off.
Being your raw material is wood, I don't know if you would get any ash in the output so putting it through a good filter initially and seeing if you catch anything I would suggest would be worth while.

Catching the lighter fractions also make the fuel easier to light off and a great blending agent. You can mix the more flammable output with your WVO or WMO to make it go further and be much more diesel like. Also cuts down on the time and effort you have to put into your cooks with the Wood or what ever.  Plastic I think would work well but could be a problem processing the raw material into small enough pieces to get into the reactor.  A large wood chipper would be a great tool for this although it would have to be big to deal with the large and different shapes of the plastic you'd likely encounter.
The other thing that makes a good raw material if you have the ability to process it or a large enough cook chamber is old Tyres. They are cooked in a lot of countries to recover the diesel type oil they get, the steel and the carbon black which is a profitable commodity in itself.
I think wood is a material that would give pretty low returns by volume but if it is what you have... OTOH if you could get a supply of engine or pretty much any other oil, you'[d get a lot more fuel for a lot less effort.

I'm building a ground source heat pump from scratch right now so wont be working on the pyrolysis till that is done

Is the heat pump for cooling I take it?

Glort,

I love the input - I appreciate it

I have to show you the research..  I will do so on Monday - I have a bunch of papers bookmarked on my office PC

First of all - my crude experiment was just that - very crude!!  my cooling water heated up before everything finished and the smoke you saw was not condensing..  that being said..  when processing wood and depending on the feedstock and catalyst - approx 1/3 of the output will be un-condensible gasses..  mainly carbon monoxide, hydrogen and C02..  its the nature of the beast..  depending on the catalyst used - this will be less or much more.  they are invisible..  again my hacked together crude demo was not fully condensing all of the condensible gasses..  hence the smoke

The good thing is that aside from the C02 - those gasses are all flammable and will self sustain the process..  the initial heating process with electricity takes less than an hour - then so long as you keep feeding the system with wood - it will keep going on its own.  I obtain that electricity from either solar or my listeroid (which could be running on this bio-oil)

Retention time is a key factor..  Ideally you want to material to phase change as fast as possible..  more advanced reactors use fluidized beds or ablative rollers that both change the wood to gas in a matter of seconds..  The auger style that I am building is much easier / cheaper to construct but has a retention time of minutes vs seconds..

Higher quality oils are produced with lower retention times..  so the size of the feedstock is important..   Yes - you can put logs into a sealed chamber and heat them up and condense the gas - this will work but the output will be much lower quantity and lesser overall quality

The auger method with small woodchips is the best compromise for the DIY person with a reasonable budget

Think of a tube inside of a larger tube..  the outside tube is full of flames heating the inside tube..  the inside tube has an auger that moves the feedstock along at the correct speed so that all of the gasses escape and whats left is charcoal which drops into a bin..  (the whole thing is sealed from the atmosphere).  The input would be a continuous hopper of woodchips that get batch loaded every 30-60 seconds or so..  this leads to several conical condensers  at varying temperatures which both drop out the solids (ash) and condense the various compounds into a liquid..  which can later be blended or further upgraded

If you want to go real nuts - you can flow the remaining vapours into a cold trap which will condense even more..  but its kinda fruitless at that point

Efficiency does not really matter so much with a feed stock that is abundant and free of cost..  so long as I can make enough during the summer months to hold me over for winter


My heat pump project is for both heating and cooling..  I bought an overstocked ground source heat pump unit for cheap and replaced the single phase compressor with a 3 phase that now runs on a VFD..  I also replaced the TXV valves with a bi-flow EEV valve (electronic expansion vavle)..  I have an open loop well source that empties into a nearby creek..  the pump is also driven by a VFD..  I have a superheat controller that maintains the superheat at the minimum possible value without sending liquid back to the compressor..   the whole thing is driven by a PLC with lots of sensors, etc..   I plan to store the heat from the listeroid in several 1000L insulated tanks and then draw on that low grade heat with the heat pump until its exhausted..  then switch to the well..  I run the listeroid for a solid 24-30 hours every 3-4 days..  I plan to store the heat in the tanks and draw from them as I need until they are depleted..  When the generator is running and the heat pump is running at the same time - the heat pump will lower the water temp going back into the exhaust heat exhanger making for a greater delta and higher thermal efficiency..  when running off the well - I get a heating COP of approx 6-7 when everything is modulating perfectly..  the heat pump (like everything else) runs off my batteries which are charged by the lister

Anyways - the heat pump is a whole other topic! 

Wood as a feedstock really sucks and is difficult to produce good quality oil compared to other feedstock such as plastic or tyres..    But I do not have a mound of plastic or tyres on my property..  I have a shit ton of trees and bush that will forever grow back

The good thing is the listeroid does not really care..  it will run on nearly anything and be just fine with a few timing tweaks, etc

[farmerjohn]

  its doable but not necessary..  the water actually aides in the combustion process

Ohhh not it doesen't and the LAST thing you want is 20-30% water in your Fuel. You don't even want 1%!

I have been running veg oil for 17 years now and unlike most I have done a LOT of hands on testing.
Water is not something you want in your fuel under any circumstances.  It will allow growths to propagate in your fuel system and it will screw your injector pump and injectors. 20-30%  water in the fuel would be a complete and utter disaster and would fk up an injector pump in no time.  I can only imagine how poorly the engine would run as well.  Barely I think would be the best description.

I have actively dried My WVO from the beginning. Not drying off even the dissolved water produces a noticeable drop off in performance, both in power and starting. that would be at best 1-2% Moisture content. 20-30% could have an even larger percentage fall off in performance.... and again I have reservations if an engine would run on that sort of moisture content.

Thing is though, there is no possible way one could have that much water in the fuel. There is no way it's going to stay in suspension so it would drop out to the bottom of the tank and stratify with the fuel itself.  If the pickup got a snoot full of that water sitting on the bottom......
No way the fuel is going to be 1/5th suspended water. Just not going to happen.  I don't know what the percentage could be but it's not going to be anything like that I can tell you.

As for the claim of making the engine run better, I hope you are not basing that in some  flawed ideal and parroted mantra that the water will break down into oxygen and hydrogen which will then burn and make the engine go better.
No, it won't, that is an internet Myth.

Firstly the temperatures required for that to happen would melt your Pistons in 60 Sec flat.
Secondly, the energy required to split the water into it's base components is more than the energy given off when they burn so you end up with a net result or a power loss. as You seem to be a man who does his homework, you can easily look this up.

Even if you started with 100% dry wood - the process converts some of the wood into hydrogen and oxygen which then combine to create water vapor

Again I'm sorry but No, that cannot happen at the temperatures you could reach in the process. These gasses will stay separate and bubble out through the output.

On my office PC - I have a huge list of scientific research papers on the subject..   I'll make a list of those on Monday and post here

With respect, if they are proper scientific papers from credibly sources that may be interesting.
If they are the typical crackpot psuedo science particularly from places like india where they seem desperate to believe in getting something for nothing and the claims are as defiant of the laws of physics as as they are of practical demonstration, please don't bother.

There is enough misinformation on the net and sorry to say but it's clearly you have fallen for some of it.  I think we all have at some time but hands on testing and real word experimentation goes a long way to clear those errors up real fast. 
I have found so much Bunkum and misinformation in the Veg fuels field it's not funny and have discovered much the same with my more recent interest in solar power generation.

Too many people out there claiming their untested opinions as facts which get parroted around till people who have also never put them to the test will argue them as indisputable fact even though they are laughable poppycock.

Wood is far more difficult than plastic or tires, etc...  I am interested in wood because I have ample supply on my own land..  I am not dependant on some outside source

That certainly makes logical sense.
For me WVO has been my go to energy supply. I can get as much oil as I want literally and it's the easiest fuel source I know of.
It is IMHO the easiest fuel source to process.  I can process 200L in my DIY processor in easily under 30 Min nad have ready to go fuel.
Having far too much experience cutting down trees, cutting them up and splitting them for firewood for my father, I know how much work and effort goes into that.  I'll take the oil any day. If he'd let me, I'd convert his woodfire heater to oil and save myself a ton of work and  buckets full of sweat.

There is nothing like the feeling of independence and self sufficiency one gets by providing for themselves no matter how much work is involved.

Glort - I am sorry but you are wrong on many levels

While water content in fuels such a diesel or WVO can be undesirable - water mixed into other fuel sources is desirable in some cases.  There have been several credible studies that show that water changes the cetane rating of some fuels to be more desirable for compression ignition

I certainly do not believe that the water is magically changing into hydrogen..   its being blown out the exhaust as steam / water

Again - I will post the credible research that I have been studying here when I get back to the office this week

Water in wood pyrolysis oil is a common problem and not easily solved..  Fractional condensation allows you to obtain various fractions that vary in both water content and volitile compounds

The main issue is that many of those compounds are fully soluble in water..  which is both a good thing and a bad thing..  the water does not stratify out nor can you easily "dry it"

Wood bio-oil does however separate and degrade over time if you do not use a catalyst during production..  mainly from the acids, suspended solids and water..  I have made several batches with my crude reactor and left the oil to sit for several months..   You will get a much thicker darker oil that settles to the bottom that easily mixes back in when you shake it up..  but never any water stratification

I have run several liters of my crude unfiltered oil in my lister..  it generated the same load as running on WVO..  only difference is that is smells like texas BBQ!  Very smoky wood smell

You will never get 100% dry wood to begin with..  there is always going to be at least 10-15% moisture content even from properly seasoned wood..  water is going to transfer over from wood weather you like it or not..  Like I said - many of the compounds are soluble with water - they keep it in suspension

I encourage you to try it for yourself..  you saw my crude setup..  its as basic as it gets..  Make some - test it - run it in your roid

The studies that I read and base my information from are credible studies that have actually built something and seen a result..  no theory..  I combine that with my real world experiments

For a long time I had a very reliable source of WVO - and I loved it..  You are right its a near perfect fuel! but for where I live - those sources that were giving me thousands of liters per year are slowly drying up

I have approx 2 -3 years worth of clean/dry processed oil left and then its gone..  For me - wood is the answer.  For others its crazy
If I had a super reliable source of waste plastic - I would not even be talking to you about wood..  Plastic is 100x easier to process and the zeolite catalyst is cheap and abundant..  For wood you need more exotic things like zeolites coated in ultra fine layers of noble metals or fumed silica mixed with titanium or aluminum oxide..  it gets far more complex

For plastic you can buy zeolite rocks from the garden center at your local walmart and pass the gas though a bed of it and come out the other end with near diesel fuel with zero water.. 

For me processing the wood into chips is a walk in the park..  I have tractors and machinery that allows me to sit on my ass while I feed a whole tree into the chipper..  the output blows into a trailer

Look up how wood pulp is made from hybrid poplars..  they have special attachments for tractors that basically mow down the 4 year old saplings to the stump and spit wood chips out the back end..  those trees then re-grow to the same size or greater in 4 years..  they keep doing that for 25 years or so. 

You either upgrade the oil or you modify the engine to handle the acidic acid..  upgrading the oil sounds more challenging and fun to me

Make some oil - have some fun with it

John

[StrawHat]

This is a spin off of the old Fischer Tropchse process invented by the Germans well before world war two. Most modern refineries use all sorts of variations of this process to make the "blended" fuels we burn today. "Straight run" refinery fuels haven't been used much since the 1950's. The Germans didn't have many petroleum reserves so they made most of there gasoline and diesel from coal using many variations of this process. We bombed a lot of there processing plants during WW2 too! These days gasoline and diesel are made from anything from crude oil to natural gas, and 90+ percent of every barrel of oil *can* be made into fuel if they want to spend the money on the refinery equipment needed to do so. Most of that remaining 10% is used to generate the energy needed to refine the other 90%. It's all a choice of raw material cost, profit and capital expense, not any technology challenge. Also, modern "full synthetic" lubricating oils are made this way.