Thanks Matt, do you mean that it is impossible to get any gas?
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Oh that stuff make plenty of volital gas. Its not going to be usable unless you can get that stuff out. This tar is not any tar you want to deal with. That stuff cures like concrete, yeah there is no fixing the vavles you will mushroom the stem trying to remove it even with a ton of heat.
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This was before I started charcoal gasification. So I have no idea if you can make it into engine grade charcoal or not. I would assume it will make very good charcoal as its already very dense. Make charcoal is not hard or labor intensive. The retort does the work, refine your fuels first its worth the added process. Take the easy road not the hard road.
Larger engines you can wood gas but the smaller the engine the more dificult it will become. There is point where constant intervention becomes too much for it to be viable. Even a solid system that is as easy as it can get is still a chore. Its not like filling it up with gasoline pulling the rip cord and it runs until the fuel runs out. Oh no you make the fuel, then you have to get the unit loaded up and fired up then get the engine running, get things warmed up before loading, Then all is good right? Yayyy you walk away and 5 min. later you are right back there fiddling with air mixture kicking the stupid thing trying to keep it flowing, then you tar up a valve. Off with the Head!! Then you get it back up and running only to repeat this process over and over. Sometimes you get lucky but with no fuel standardation, your success is in your hands.
Charcoal is where everyone should be starting. You dont become a brain surgen overnight. You go to college for years to get there. Learn this foundation first. I wish I could start over and start with charcoal. I wasted many years of my life chasing this and I dont care if makes people here angry. Im being realistic and pushing the right path forward.
When you can opperate a retort and learn to do this without any smoke then you have mastered the pyrolysis and distilation process. You will have to learn to use pre dried fuels and how much moisture you can get away with to get to this result. You will learn to make good charcoal that is a requirement in any gasifier. It is the heart of it. There a lot you can learn here before you build an actual wood fuel system and this knowledge to shape your project and be more successful.
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Because it is small bits of wood stuck together with glue, you are going to have a hard time getting a bed of char that cracks the tars from the actual wood and still has enough gaps to let air pass through it like is normally done with the gasifier designs we typically use. So you could add it to say other actual wood, to keep the bed going, but wood is at a premium in Ireland.
Honestly, I think Matt is on the right track.
Here is one study on making char, and the study itself isn’t that important. the citations section is. (Plus it isn’t behind a paywall that you have to use sci-hub.se to try and access the paper). https://www.desirabletomorrows.org/assets/files/Conversion_of_MDF_wastes_into_a_char_wit.pdf
They reference a study that is making bio-oil, char and a gaseous product with both a screw retort and a microwave.
The char is easily usable as say biochar, and most of ireland has very poor rocky soils, add the right microbes via say compost or vermiculture, then plants/garden, etc will go boom.
If you condense off the liquid fraction, into what they are calling ‘bio-oil’, there are enough chemical companies in ireland that would buy it. One other issue is MDF contains urea-formaldehyde which a study in Brazil was saying could be used as a fertilizer. You may also be able to dewater the liquid (heat it to 105C) and use it as a diesel fuel. You probably have to dewater it before selling it to a chemical company anyway.
When briefly looked at the screw retort study, they were using 15 minute residence times, so it actually sounds like it goes very quickly and a lot faster then I would trust for just burning off the gases to sustain the reaction. Thus I would highly recommend looking at something that condenses the liquids off. Which is a closed retort, and used for making “wood vinegar”. A batch process would system is essentially a pot still. The screw is a continuous system. They used like 1mm particle size and smaller, and another study used up to 20mm in size, so it would probably need to be chipped.
The bottomline is you can get heat plus some other valuable materials out of it as well as avoid disposal costs. It very well could be worth your time. I suspect you have quite a bit of it.
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Its an issue here as well. They dont want that stuff in the landfills and they charge extra to dispose of that stuff. The guy built a huge outdoor wood boiler to heat his shop with that stuff but even though he has tons of it he still has to process fire wood to burn with it otherwise it will make everyone within a miles range sick.
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I thought MDF was allowed, but you are probably right. I don’t usually use it. You have to landfill pressure treated lumber because of the arsenic.
I was looking for the reaction products from burning it, and I haven’t found them yet. that is also why I was suggesting condensing it out. I suspect most of the stuff that reacts will be condensed out.
I eventually will get back to looking at what bacteria break it down. It may not be the fastest, but it could be the easiest. I don’t want to breathe the fumes. I don’t think anyone else really does either.
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Its only an issue for big shops that produce tons of the scap on a daily basis.
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According to this, UF urea-Formeldahyde is the most widely used bonding agent in MDF. Soaking in water for a month it will dissolve in the water… There are also bacteria that will decompose it.
https://www.sciencedirect.com/science/article/pii/S2590123023004048
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Yeah look that stuff up, its extremely toxic. In mass concentrations I can see why they dont want it.
Asked google AI: UF urea-Formeldahyde does water nuetralize it?
It returned: No, water does not fully neutralize urea-formaldehyde (UF); while water can cause UF to break down and release formaldehyde over time, especially in high humidity or temperature conditions, it does not completely neutralize the resin, meaning the chemical bonds within the UF structure remain largely intact unless exposed to significant heat or specific chemical treatments.
Edit: Asked AI: uf urea-formaldehyde biodegradable?
Returned: * Biodegradation
UF resin is difficult to biodegrade and can remain in the environment for a long time. In one study, UF resin was buried in soil for over 32 years and showed no evidence of biodegradation.
- Recycling
UF is difficult to recycle because of its chemical composition and the difficulty of separating it from other plastics. Mechanical recycling, where UF is ground into small particles, is limited in its effectiveness. Chemical recycling, where UF is broken down into its constituent parts, is more effective but can be expensive and energy-intensive
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I’m ready for some more schooling so I’m going to risk being a dummkopf. All the reasons given for MDF or it’s courser cousin Particle board to be unsuitable for producer gas production seem valid. In a updraft charcoal design much of the volitiles in the glues would go with the smoke. My understanding is that the problem with downdraft charcoal is that the reaction can be too hot and cause more rapid deterioration of the vessel.
My experience burning MDF in my wood stove is that since I run the stove full bore for intermittent periods the glues are never allowed to smolder with the fibers. Going outside with the stove burning has never given a hint of unusual odors. I therefore think that these products can be a resource for building heat with various storage methods, hot water production, ect, if they are used in a furnace engineered for the purpose. Anything can be basically purified with enough heat. Even tires can be safely converted to a fuel to heat the water in power plants if it is fed enough supplemental oxygen.
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I think that maybe refuruing to a wood gasifier running pure charcoal? Water injection should not ever allow it to get that hot. Thats not my experience with any machine Ive ever built. I have never seen a core degrade in anyway ever. When they are power washed they look like they have sand blasted is all.
Yeah as long as you can burn off all the gases it shouldnt be an issue.
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Hydrolysis/water cleavage and/or high temperatures break the urea formaldehyde bond. Once that bond is cleaved then nature can take over as both mononers, urea and formaldehyde, are found in nature and there are bacteria that treat it…
Formaldehyde itself burns primarily to CO, CO2, water.
The article in post 22, actually goes through a number of ways people have tried, including pyrolysis and includes the references to studies. One issue is either the writer of the overview or the study itself, was focusing on the reuse of the wood fiber.
We are looking at a broader scope of how to get some value out of otherwise trash that we would have to pay for.
So as long the gases are burned off with say a secondary burner, you wouldn’t have much if any formaldehyde left.
However, again that isn’t the only resin used…
Here is google AI contradicting itself slightly.
Urea-formaldehyde (UF) resin, while not easily biodegradable, can be broken down by microorganisms under certain conditions. The decomposition process involves the hydrolysis of the resin into its constituent monomers, urea and formaldehyde, followed by further breakdown of these monomers by various microorganisms.
Here’s a breakdown of the biological decomposition of urea-formaldehyde:
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- Hydrolysis:
The initial step involves the hydrolysis of UF resin, breaking the bonds between the urea and formaldehyde molecules. This process can be accelerated by factors like moisture, temperature, and the presence of certain enzymes.
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- Urea Degradation:
Urea, a nitrogen-rich compound, can be broken down by microorganisms through the enzyme urease. This enzyme hydrolyzes urea into ammonia and carbon dioxide.
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- Formaldehyde Degradation:
Formaldehyde, a toxic compound, can be degraded by various microorganisms through different metabolic pathways. Some bacteria can oxidize formaldehyde to formic acid, which can be further metabolized to carbon dioxide and water.
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- Microbial Communities:
The decomposition of UF resin involves a complex interplay of various microbial communities. Aerobic bacteria, anaerobic bacteria, and fungi can all play a role in the breakdown process.
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- Factors Affecting Decomposition:
The rate and extent of UF resin decomposition depend on various factors, including:
- Moisture content: High moisture content is essential for microbial activity and hydrolysis of the resin.
- Temperature: Optimal temperatures for microbial activity are generally within the mesophilic range (20-45°C).
- pH: The pH of the environment can influence microbial activity and the effectiveness of the decomposition process.
- Nutrient availability: The presence of other nutrients, such as nitrogen and phosphorus, can enhance microbial growth and decomposition.
- Type of microorganisms: Different microorganisms exhibit varying abilities to degrade UF resin, with some species being more efficient than others.
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Hey guys,
Thank you all for such useful info and thank you for taking the time to go into so much detail.
I’m going to run a few tests this week and will come back with some pics and results.
Looking forward to this project and sharing it with you guys.
Chat soon
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Hey guys,
Planning on my first test just trying to see if I can get MDF to gas and going to set up a simple rig like this.
Anyone know what sort of temperature I would need to get it to to gas? Even what do you guys get your gasifiers to would be a good guide.
Thanks in advance.
Ian
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Hello Ian
The video may not be a good example of a gasifier . It would lock up a motor on the first run .
The gasifier is an up draft design which is not good.
You should not see any smoke being produced and the cooler the gas the more btu.s it will have and should light off easier . The video mentions the wood was spent but it is now refined and ready to produce gas .
As far as the temperature of the gasifier the core should be at metal melting temps but built in such a way that those high temps never reach the metal.
Happy new year 
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What that is a closed retort charcoal maker. You should end up with charcoal in the first container. Ironically you can use a similar system for plastic to oil.
Wood is for charcoal gasifiers is usually on the hot side, like 700-1000C.
Make sure you don’t breathe the gas coming off. over 300C the UF breaks down and creates a bunch of radicals.
From google AI.
The thermal breakdown of urea-formaldehyde (UF) occurs in four stages, with each stage involving partial volatilization and chemical modification of the polymer:
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Below 200°C: Methylene ether bridges are converted to methylene bridges, and branching and crosslinking reactions occur.
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Above 200°C: Radicals formed by chain scission cause the formation of cyclic structures in the polymer.
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Above 300°C: The polymer undergoes extensive fragmentation.
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Final stage: The carbonization process occurs over a wide temperature range.
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Lan, I agree with what Mr. Wayne wrote, this video only shows the pyrolysis process, where oily pyrolysis gas is released, which you cannot use in the engine, as it will quickly create a thick coating of tar in the pipeline and intake manifold. Wood consists of three elements (carbon, hydrogen and oxygen) in an ideal ratio, so that the energy of the exothermic reaction that takes place above during pyrolysis would be sufficient to convert the gases in the lower part, where the endothermic reaction takes place (splitting of water vapor and tar gases in glowing coal). Due to the heat losses of the gasifier, we have to additionally burn the wood, and thus excess water vapor is created, which is condensed above and separated from the process.
Since particle boards contain a lot of glue, conversion in this way is questionable, the “modern” and controlled method of gasifiers is based on electric plasma, where electricity is used to maintain a plasma layer with a temperature of over 4000°C, which is about 10% of the energy produced by the gas.
Another picture of what wood gas looks like just before the engine starts.
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Hey guys,
Thanks for all the info. Fully agree the vid I showed isn’t suitable, just wanted to do something simple to see if the MDF I have can gas before I go making a gasifier that can deal with all the tars etc.
I have a good idea of what temp I need to get to and I’m sure I can mock up something very simply just to test if something is actually achievable.
Also, if there is some tried and tested designs I should be looking at for my gasifer id really appreciate if you could show me where to get them on the forum.
Thanks guys
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Following tried and true procedures from those you have gone before is the best plan but sometimes a few failures can teach you more than a lot of proven successes by others… As St Paul taught. “test everything and hold fast that which is good.” 
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Here’s a link to my small beginning. I still think it was a good way to get started.
Rindert
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