Crazy englishman wants to build log gassifier.

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BONE

Member
Dec 6, 2010
10
ENGLAND
HI GUYS
Can anybody help in the building of a log gasifier, looked at some good examples,NOFOSSIL,andGULLANDS, i am a plater/welder so fab side no prob it seem to be the fine parts causing trouble ,everthing relates to each other part, firebox size, combustion chamber size ,gap and size of refractory nozzle.If anyone can help it would be appreciated.I have quite a passion to suceed with this project and would luv to start something of this nature over the pond and swop info with like people
THANKS BONE.
 
Good luck with this endeavor!! Would love to see photos as you prgress. Where in England?? We lived just outside Newmarket for several years....Go Spurs! :)
 
HI DUDE, peak district,derbyshire ,very near chatworth house, will keep everybody posted when gathered more info thanks for reply. spurs, got to mention chesterfield town fc my friend would kill me if didnt.
 
I love the Peak District. I spent some good time in Buxton and north. Oh man- I get a crazy feeling thinking back to hiking around there- despite having my ex wife (then married) with me at the time.

Welcome aboard here
 
BONE, when I was traveling over on your side (35 years ago) I met the legal definition of vagrant and vagabond and thus was not allowed onto the isles. In truth, it was a fairly accurate description and I hold no grudge.

A lot of discussion and mutual cheering on (with photos!) has gone on here over the last couple years on this very subject of building your own. Learning to use that 'Search' button up near the top of the page and the little "Advanced Search' link in purple right under it will get you many an evening full of reading (and probably some amusement). Replying to any old posts that interest you in particular might get you some updates from the very people whose projects interest you the most.

And welcome aboard.
 
Hi daveBP
I bet when you was over here looking like that you would have fitted in quite well with some of us locals. thanks for reply and advise.
 
There are several cautionary threads that discuss gasifier design and build. It certainly can be done, but there's a lot more science to it than you might think - not least controls and materials science. If you're comfortable with the concepts of stoichiometric oxygen ratio and superficial velocity, go for it. If these are new terms, some additional research will improve the odds of success.
 
HI GUYS
Thanks for all your efforts in replying back got good feed back,and some cautious ones to ,need to look and study some more,going to act on advise from this site,that these beasts need to be fully understood before jumping in ,so keep education lesson coming and i will soak it up like a sponge once again thanks for making me welcome. BONE
 
The boilers available in the UK tend to be much more technical than those in the US.

I would look at the simpler/older designs and copy the bits you like, trying to start from scratch would cause too much heartache.

There are people who have built their own Garn type boilers, my guess is that this sort of design would be easier to construct?
 
Hi Como
Have been looking at these garn designs before coming on to this site,might try this design before attempting the holy grail of gasifiers, will have to make a baby garn as you can swing a cat around my log cabin(house). fab looks quite straight forward ,but good project for virgin boiler maker.Have seen the garnification what a piece of kit.
 
BONE said:
Hi Como
Have been looking at these garn designs before coming on to this site,might try this design before attempting the holy grail of gasifiers, will have to make a baby garn as you can swing a cat around my log cabin(house). fab looks quite straight forward ,but good project for virgin boiler maker.Have seen the garnification what a piece of kit.
I would be happy to help with dimensions on my Atmos etc although these can probably be looked at in the UK. My suggestion would be to build a downdraft gasser with about 6 vertical firetubes in the back. They would be about 3 1/4" to 3 1/2" diameter & you can turbulator them for the flow you want. You would build with a primary chamber to "cook" the wood & you need some overfire air there, The gas goes through the nozzle & you need preheated air that feeds into the gas right at the nozzle, then some sort of lower burn chamber(typically round ceramic lined) doesn't have to be round. Then all you do is duct the gas to the bottom of the firetubes. I would use a suction fan design. I was going to build one & when I priced good boiler plate & everything else & my labor I bought the Atmos, Randy
 
By all means, build to your hearts content. We love to hear how these projects turn out.

I'm on boiler version 1.15 and I've seen a couple of shop built gasification boilers. I've come to the conclusion that gasification is a neat trick, but for burning wood cleanly, efficiently and economically, you can do just as well with simpler technology.

For one thing, the main advantage of gasification seems to be that it can idle without smoldering, but then everyone recommends using water storage to eliminate idling, which is kind of like building a car with regenerative brakes and then driving so conservatively that you never use the brakes. That seems to be the strongest point of the garn, it's a simpler design that makes use of the storage to keep from having to deal with idling.

Look into old books on coal boilers and "dutch ovens" not the cast iron cookware but the furnace design that was basicaly a longer refractory lined combustion path before the combustion gas hit the cold boiler surface. Coal technology from 100 years ago was much more advanced than I would have guessed, you can apply the same principles to wood, with a little conversion.

If size is a factor then storing the heat in a masonry floor is a good option, or a masonry heater-russian stove.
 
benjamin said:
For one thing, the main advantage of gasification seems to be that it can idle without smoldering,


I must have missed this advantage. My EKO gasiffier missed it too! I thought the point was to keep it out of idle so it wouldn't smolder.
 
Diddo DonL,

Where do automobiles get better fuel mileage? Stop and go traffic or steady highway speeds? Where does and engine burn cleaner at? Stop and go or @2000 rpms steady?

Idle you get slime, Wide open you burn Fine!
 
I think a real comparison should be made. Radiant can easily use lower temps to satisfy heat loads using storage but air handlers require higher heat for the same task. It could quite possibly be more effective to use a massive amount of storage to keep an air handler satisfied but reading comparative fuel usages to heat the storage for radiant vs air handlers leaves one wondering. People with around 1000 gal. storage talk about their summer wood uses for dhw and my EKO40 will burn about the same amount of wood or less for the same time period while using the idling method (part of that is partial load burns and actual dhw usage). As a side note motive force is not really a relative comparison for heat production. Stop and go traffic certainly reduces mpg but at idle the engine will produce the needed water heating capacity to keep one warm in the passenger compartment of the vehicle once the motor is up to temp. for a longer period of time. One might stay warm longer on a given amount of fuel at idle than at 55 mpg but one would never go anywhere. Just and inquisitive .02. :)
 
I think the biggest advantage of storage is the convenience of burning, followed by lowering the need for cleaning the unit. I don't think anybody would argue that you will save much wood just by adding storage.

I think DonL was saying that his eko still smolders at idle ( I bet it's not as much as the typical OWB though), which would prove my point that there is very little advantage to gassification (downdraft with nozzles etc.) over something simpler like a garn, masonry heater or homebuilt unit with reasonable air control, complete combustion and plenty of storage to burn "flat out". The only efficiency gain would come from much better air control.

No analogy is perfect, but I think understand what you're getting at with idling. Especially if you have dry wood, and if you don't over fill the unit, you don't need more than a small "buffer tank" to store the heat it takes to burn down to coals, and then the unit can idle with very little wasted energy, or smoke/creosote.
 
I believe a gasser can run much lower flue gas temps than anything else without creosoting anything up & that gives it a big efficiency advantage. You can choke down any boiler or stove & get some good numbers, you will really need to keep after the chimney though, Randy
 
Right, very, very little smoke and since the unit is very nearly up to or at temp the gasification starts immediatelywhen there is a call for heat. During the summer with my EKO40 however I would shut the unit down completely once the unit and dhw were up to temp. (the circ fed the sidearm hx to the dhw and ran 24-7 and via manual controls kept the flow through the boiler and prevented overheating) With basically zero air flow there was usually no problem re-igniting the next days fire as the charcoal was already on the nozzle and generated heat quickly and achieved secondary combustion shortly after reloading the gasification chamber. The shoulder seasons were less economical though than the summer. The biggest problem is probably the high temps needed for air handlers.
 
I live in Hobart Australia and I am currently building a STICK-WOOD FIRED FURNACE as designed by Richard C Hill.

This is a relatively simple design that is proven and I believe can be built by someone at home.

The design is readily available online in a PDF file

I don't know anyone that has built one but would like to hear from them if they have.

I will be using the boiler to supply heated water for the hydronic heating system in my home.
 
Hi Hobartian,
I am good friends with Dick Hill and have the plans on our website www.hotandcold.tv, along with his recipe for Bean Bread.

We have had several units that we have built over the years and continue to develop the basic design which is the basis for most if not all
the gasifiers out there today.

Good Luck with your work.
Of course, we need pictures from Down Under!!
 
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