Troy Martz Gasifier

[abeconnally]

Ray, I used to live in Texas on the border, near Big Bend. Not much in terms of wood our there! And boy, there’s enough heat to spare!

Here we have juniper, a bit of oak, a bit of pine, not much mesquite, but in the river valley below there’s a lot of poplar, willow and things like that. I have a decent amount of juniper, but I don’t know how good charcoal is from that. My main source of wood for charcoal or wood gas would probably be from the apple/fruit orchards. Lots of prunings and small stuff people don’t use for wood stoves. Most of it is in the 1-2" range, which goes through our chipper easily. We have a rocket mass heater in the house, but we rarely use it. I have a pile of small, split oak I use for that.

I do have some small engines around here, a welder, a chipper, hammermill, all of them could be put on a charcoal setup and for those it makes great sense. I don’t use any of these that much, so a few batches of charcoal would last a good amount of time for them. I had thought of making something like Stephen’s Victoria gasifier to run those small engines on wood chips, but I may jump straight to a simple fire or something like Koen’s setups on charcoal. I’ve been collecting parts for a gasifier for years, got several tanks together, lots of spare metal and fittings. Anything that simplifies that first gasifier will help me get my feet wet and get something running. I like the simplicity of the charcoal setups for that.

As for cheap solar, you can search online for deals and sales, I saw some recently on sun-elec for $.32/watt, and even with shipping, they’d be pretty cheap. You have to order a pallet at a time, but it is still worth it. I’ve been on solar for about 14 years, and in that time I’ve seen it go from $5/watt to less than $.50 a watt. I imagine this time next year it will be $.40/watt or less. I have considered an electric car for local travel many times, especially with solar getting as cheap as it is. But finding an electric car here is difficult, at best. I’d have to convert one, and that’s a project that would have to wait on the backburner.

Part of the reason for getting on gas for things around here is help my neighbors do the same. There’s a lot of old ranch trucks around that would be great candidates for running on wood.

Is anyone running bigger vehicles on charcoal?

[k_vanlooken (Koen Van Looken)]

Actually one can not do without the other

For me a charcoal unit is the half part of a wood gas set, as where my charcoaling unit is the other part.

now i have to get them working on the same spot and at same pace… there lays the challenge…

Solar, wind, waterpower Hydrogen, those are Non Carbon emitting fuels , within reach and preferable for the future.

But using wood as energy source instead of wasting it by natural decomposing, is already useable and basically the only option in a process of transition. You can make any old car run on wood gas, any IC engine, any gas turbine…

Just do it…

The choice of charcoal for colder regions and specially for of grid situations, are perfectly explained in a setup case as with David Baillie
Use the heat from the charcoaling process for household and the charcoal as engine fuel seems to me as a perfect idea…

Using straight wood in your gasifier… nothing wrong with that
Using charcoal because it has its advantages … nothing wrong with that either…

Actually our ancestors gave use the example, already those days they where spare with using energy and weight on vehicles…

My statement seconds many statements already made by others… use your BTU’s don’t waste them

[Troy_Martz]

Chris, we reached out to Marcin Jabukowski about adopting the OpenFire. In order to “play ball” we had to agree to releasing our design in the MOST non-restrictive open source license around (CC-BY-SA). This was a tough decision for us, because we have a business we want to build around alternative energy.

In essence, the Creative Commons license allows others to build and profit from it. or even modify and profit from it… Because I’ve stood on the shoulder of giants (Gary and Koen in particular), we eventually thought it was a good thing, and will release this to the world as CC-BY-SA.

https://creativecommons.org/licenses/by-sa/2.0/

We hope to leverage the talents of electronic hackers as well, for Arduino / Raspberry Pi, actuators, servo motors, sensors, etc. The Open Hardware movement is thriving, and I hope this gasifier design evolves into a solid solution.

Troy

[k_vanlooken (Koen Van Looken)]

On topic: using designs to generate as much as possible energy from the carbon source wood, all off us have jump a few hoops.
a full raw wood gasifier combines two main processes, which a charcoaler has separated.
turning the raw wood into a glowing mass to reduce useless smoke, gasses and carbon into energy.

after reading this topic http://driveonwood.com/forum/1614
i am more convinced and learned, separating the two processes is ideal to overcome quite a few issues what comes with raw wood.

we all know how difficult it can be to turn raw wood into charcoal…
how many different styles we can use to make the charcoal… the smoke, the avoidance of the smoke, the residue’s building up in the tank ( but we have an auto-clean function by burning that away ) and the moister…

ranging from a good basic simple fire (Gilmore) to an good open fire ( Troy Martz) there are little issues left to adress in a charcoal gasifier.
Problems are taken care of in the charcoaling process. Read all the comments in the earlier mentioned forum topic and understand which problems they solved or have to solve.
We don’t have much of those problems… we have the advantage that we can focus on the process getting more power out our charcoal, adding water to generate more free power, using exhaust return to improve the working. little tweaks at low cost and no headaches… more power on the wheels whit less hassle…

lets take 2 similar trucks, put an equal weight on them (gasifier and feedstock) and start driving and refill, driving refill, on and on
i think the simple solution win’s way ahead.

put those two original trucks next to a junkyard and a huge pile of wood, choose your build style gasifier and try to get as far as possible as soon as possible…
I think the simple solution win’s again…

Keepin it “simple” convinces more people and create followers… thats what we need, followers… following the footsteps of those who did build and use wood as fuel…

I bow my head for those who did build before me and inspired me, and encourage others to follow…

Keep your solution simple, it brings you further…

[abeconnally]

I agree that simple is better. But, when you talk about a pile of wood and getting the most mile/km out of it in your vehicle or hours of run time on your small engine, there’s a significant difference in each approach. The charcoal generator is simple, no doubt, but you’ll get less hours and less miles/km from that pile of wood. That’s only one perspective and way to look at it, though.

From an infrastructure and materials standpoint, the charcoal gasifier has less parts, but when you include equipment to make charcoal, I doubt you come out ahead. Sure, you can make charcoal in a simple way, but making charcoal efficiently and simple don’t go hand in hand, it seems.

For long-term use, it’s not necessarily simple that wins. It’s resilience, ease of operation, and labor involved. I think charcoal comes out ahead for the first 2, but labor, it is far behind wood gas.

Charcoal gasifiers, like the simple fire, are a great way to get people involved in gasification, but we need to take it a step further. The char production process needs attention, as well. 18% efficiency in making charcoal seems low, it seems like we could do much better with that.

I think each approach is appropriate to certain situations/circumstances. Charcoal gasification has it’s uses, as does wood.

[k_vanlooken (Koen Van Looken)]

I did mention 2 identical cars, with 2 different scenario’s.
in that perspective, what do you think is the outcome ?

In another perspective; 2 same cars, pile of fresh wood and junkyard… closed circuit to drive around, count the mileage, time, carbon exhausted,
i can use the water to drip in and the tar condensate and recycle the carbon dioxide…

i agree with any outcome, but lets put it to the test in a friendly competition? A kind of world cup, canonball race on wood ?
So much fun to develop for the sake of a greener future.

[abeconnally]

A World Gasifier Cup is a wonderful idea, Koen. We should really do that. You could have different categories, depending on engine size, etc. That would certainly start getting people interested in gasification. I remember an article in Make Magazine several years back about electric drag racers. Some of those vehicles were amazing, and could run circles around petrol vehicles. Things like that grab people’s attention and show them the potential of the technology.

In your original scenarios, simplicity wins, but that also depends on your definition of simple. To me, something like a Victoria gasifier where you can throw in a bunch of wood chips is simpler than making a retort, then making charcoal, then putting it into a simple fire. The other side of that is that none of us are really living those scenarios. We all have time and are able to select appropriate parts and materials. Yes, simple is better in certain scenarios, but for regular use, simplicity is not the only factor (though it is certainly a major consideration). Labor involved, efficiency, longevity, etc should also be considered.

I would certainly like to see results of a straight comparison between charcoal and raw wood from the perspective of a limited supply of raw material (one pile of wood, same vehicles).

Another consideration, as you have mentioned, raw wood gasifiers are gasifying charcoal as well, could the raw wood gasifier use water and exhaust in a similar way to your charcoal models? It seems like if you have a nice hot bed of charcoal in your hearth, that cracking water and recycling exhaust should also be possible.

[tritowns (Arvid Olson)]

you won’t need to add water to a wood gasifier… the wood itself will always have water in it.

[abeconnally]

Arvid, does it have as much water as Koen’s system, he’s using 1 kg of water per kg of charcoal. That would make some pretty wet wood, no? And in a raw wood gasifier, does the steam get cracked like in Koen’s design, or does it pass through to be condensed out later?

[Chris (Chris Saenz)]

Wood gasifiers always have enough water, at least using air dried wood with normal air humidity. Sometimes the wood is wet enough that we can try very hard to condense it all, and some will still pass through the process, right to the motor. That’s why we have to air-dry the wood to some extent. At 12% moisture (normal air dried wood) 70 lbs of wood will contain around a gallon of water. We can run twice that % with no major issues in the Keith design.

[abeconnally]

1 gallon to 70 lbs is considerably less water than Koen is using. Even if you doubled that, you’re still less than 1/4 of the water he’s using. Also, from what I can tell, a lot of the steam makes it way through uncracked in a wood gas system, so is not really helping you. In Koen’s system, he is actually thermally cracking the steam into H and O. It may be that wood gas systems don’t get hot enough to do this in significant quantities.

[Troy_Martz]

First, let me start by saying the gasification challenge would be a great one for publicity! You can count me in… Argos (next year)?

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I’ll never be a guy that tries to put down or diminish biomass gasifiers. It’s ridiculous to say one is “better” than the other… “Better” is subjective. All we can do, is separate the functions of both types into smaller sub-systems, and use science to measure and explain our observations.

Arvid makes a good point about the latent amount of water in dried wood. And with a biomass gasifier, some of the H2 comes from that water, and some comes from the hydrocarbons. However, we are not talking about apples to apples here. Let me explain myself…

I have several books here I purchased – Mostly about Hydrogen production. I looked deep, and read, and re-read, and re-read until it started to make sense for me. (I’m not particularly smart… just driven… takes me a while). This whole steam cracking business is not new at all. before steam reformation of methane, the preferred way to produce H2 was through coke gasification. Well… We don’t use coke, but we can assume that pure carbon (charcoal) will behave in a similar manner… Fair assumption?

It all comes down to TEMPERATURE and a large SURFACE AREA catalyst. It’s my assertion that the Imbert design will never achieve the volume of steam cracking as a properly designed charcoal gasifier, because it just can’t – by design.

Issue#1: Nozzle air velocity… Unless a multi-nozzle, Imbert-style “hot zone” can reach 1,200 C – and stay there, steam cracking can’t ever be complete. Imberts are usually multi-nozzled, and sized to match air flow to hearth diameter… Something like ~5% of the total air nozzle area to hearth area. There is nothing inherently wrong this practice, but there is a direct correlation between air nozzle velocity and heat.

Because of the Imbert’s dual-role in both pyrolysis AND oxidation/reduction, you can’t use a single nozzle in the hearth. if you did, you would have incomplete oxidation of tar gasses, because of combustion “dead spots,” and it would gum up your system.

On the other hand, because we are NOT trying to solve two problems, pyrolysis not being an issue, the single nozzle in a charcoal gasifier can reach enormous velocities, makes it’s own oxidation/reduction zones, and can be placed just about anywhere you want it to be placed. We chose to place it in an updraft position so that it would keep the smaller sized feedstock in a kind of suspended animation – just floating there in extreme heat and turbulence. Any dust sized charcoal pieces are vaporized and converted into useful CO, and the ash will either caught in the filters, or slip through the ash grate.

Issue #2: Surface area… Our best results – which are inline with Koen’s – was with a fuel size range of 1/16 - 1/2". This is what the char bed might look like AFTER the oxidation / reduction zone in an Imbert. This is where I think the APL guys made the most progress, in my opinion. That new basket design essentially forced char down over that cone, in all directions, then back upwards, forming a kind of torroid shape for better, longer reduction time. This is as good as it gets for Imberts. There just isn’t enough charcoal for full, complete, endothermic reduction.

There can’t be… Because if that was not the case, then why does the gas need to be cooled down in an Imbert?

Additionally, and in my experience, the size of the feedstock in a biomass gasifier once it reaches the combustion zone, is still about twice as big as the ideal surface area for cracking steam. This is why tar still makes it into the gas flow, and is one of the biggest challenges for Imberts. Because it’s a downdraft design, smaller feedstock sizes effectively plugs up air channels for pyrolysis gasses and heat to make it’s way through.

The prototypical 1" x 1" x 1" cube-sized feedstock is only ideal because it’s large enough for pyrolysis gasses and heat to flow freely, but will reduce in size enough to still allow for decent incineration of pyrolysis gasses, and to a lesser extent, steam. Just imagine of somehow the surface area in an Imbert’s combustion zone was quadrupled? No tar would escape…

Issue #3: Carbon burns hotter… There is a reason that blacksmiths use charcoal for metal-smithing vs. wood… Carbon burns hotter… Thus, by it’s very nature, it’s giving operators a head-start in cracking steam from the get go. Wood burns twice: First the pyrolysis gasses; and secondly, the carbon.

So, with much higher oxidation zone temperatures, and exponentially higher surface areas, steam will readily crack, and will do so completely if the temperatures are maintained.

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Biomass gasifiers can’t ever be as efficient and as complete as a “steam cracker” as a charcoal gasifier. Why should we even care about steam cracking? Two reasons:

1. Essentially, for the cost of clean water, we have 50-100% more fuel… free fuel?

2. H2 in the gas flow affects the burn characteristics, thus acting as a kind of kindling for CO. This is called a “Hydrogen characterized burn.” H2, at sufficient quantities, and when mixed with other fuels, acts more like an H2 burn that the other fuel. Because of Hydrogen’s extremely fast flame front, we can then retard our spark ignition to nearly top-dead-center, for an increase in engine efficiency.

We’re still dealing with “heat engines,” right? And an explosion, acting against an upward moving piston stroke – to me – is anti-productive with regards to efficiency.

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So, my contention is that charcoal gasifiers aren’t better than biomass gasifiers… Nope. To each his own… It’s all about “context.” More accurately, it’s all about “holistic context.” What makes more sense for the situation? Am I going to convince a guy like Wayne Keith to convert? Heck no! His context is already dialed in and optimized… The trucks, the farm, the trees, the processing equipment, etc. is already in place and dialed-in for biomass… Nicely done, sir.

But my context – being a die-hard Permaculture advocate – I believe that biochar is a remarkable substance (for a variety of reasons), and is the byproduct of making feedstock for my charcoal gasifier… To me… that’s awesome!

Troy

[Troy_Martz]

If you’re interested in H2 production – especially with gasification – here are some books I recommend. You can purchase them from Knowledge Publications, except for the green one… You have to purchase that directly from Vesa.

[abeconnally]

Troy, I think you hit the nail on the head. Holistic context. Some situations/setups (like Wayne’s) will favor wood gasifiers, others (like Koen’s) will favor charcoal/H2.

Thanks for the explanation about why biomass gasifiers aren’t great at cracking water. The addition of water in the quantities that Koen’s doing is certainly an advantage for charcoal, cause you are able to make up for some of the engine power losses common with biomass systems. In big trucks, that’s not as big of an issue, but small engines need to make the most of what they have, as they don’t really have a lot of power to spare.

1200C should be hot enough to crack lots of potential fuels, as well, like waste/raw oils.

[Chris (Chris Saenz)]

I’m very curious Troy - what percentages of hydrogen and CO are you getting from a water-fed charcoal gasifier?

Wayne’s gas has been analyzed at about 20% hydrogen, 20% CO.

[abeconnally]

what’s the other 60%, Chris?

[Chris (Chris Saenz)]

The rest would be a smidge of methane (2%) carbon dioxide (10%) oxygen (1%) and the remainder nitrogen (47%)

Test results here: http://driveonwood.com/resources/pdf-articles/auburn-university-efficiency-tests

[Troy_Martz]

Chris, I really wish I knew… We haven’t had it tested yet. We haven’t even completed the initial build of the v.1.0 of the OpenFire…

Most of my assumptions come from both Koen’s experiences with his unit (we are emulating his basic core design), and from the information in my books.

Based on both sources, we would be something like CO ~25%, Hydrogen ~25%, Nitrogen ~50%… There are some methods in P.L. Teed’s book, The Chemistry and Manufacture of Hydrogen," that claims Nitorgen ~1% when alternating between air blasts and steam blasts. Steam blasting onto hot carbon lowers the temperature of the oxidation zone, which requires an air blast to raise it back up to cracking temperatures.

Of course, you would have to have two gasifiers, to leverage this on-again / off-again gas production, and build some kind of contraption to switch between the two systems… Definitely beyond the scope of what I’m trying to do. Our approach would be to try to build a simple system in which the steam would auto-regulate itself based on temperatures.

Koen was seeing something like 50/50% water to carbon by weight… which is astoundingly impressive. I’d be happy with half of that

Troy

[Troy_Martz]

Chris,

Not sure why I was double posted above… Anyone else seeing that?

I just wanted to add one thing… The gas composition would be very similar with regards to burnable and inert gasses… Right? Some may say, why go to all the trouble if the final flow is too close to matter… Fair enough.

The difference may come in how efficient the charcoal retort is… In other words, let’s assume that I have a super-efficient retort. In a perfectly insulated retort, with all things being equal, you only need about 30% of the pyrolysis gas BTU’s for a complete, self-sustained burn. The other 70% of that energy can be put to good use.

If my retort is not efficient, and I am not using that extra energy for some functional “work,” then it becomes very difficult to win the BTU argument.

Troy

[k_vanlooken (Koen Van Looken)]

Troy,
First i second the above …
I would love to be able to express myself that way…
The gas content, i reached levels of both H2 and Co hitting the 40% marker.
That was at ashmelting temperatures ( almost 1500°C) with mango wood charcoal.
using old style water vapor alternating with air and core sufficient big ( near the coil ), the steam will replace the nitrogen and supply just a little to low content of oxygen.

I think about the contest and may i suggest following… since traveling thru continents with cars driving on biomass is a bit to much expensive, i suggest that we define some rules for claims to be validated and results monitored.
Any idea’s ?