" First thing we offer guests here is a jar of carbon soot to wipe on their face. Really, no kidding. Most refuse, but a few brave ones…"
April ,
I like that.
Also , When should the gasifier be maintained ?? Just before bath time.
1 Like
Patrick,
Was just thinking that if you have a ton a day of wet sawdust then you have a half ton a day of fuel. More or less half the weight of that sawdust is going to evaporate out.
Our briquetter is a Biomass Briquette Systems LLC, model # BP-100. You should be able to pull their page up and get all the details.
Grate design would have to be critical. If you have a gasifier that continually clogs up with your feedstock you have an expensive pile of metal. Max from Europe side of the pond has a lot of excellent info on grates.
Problem with moist fuels is that the heat needed for pyrolysis of the gases would be sucked up into making steam, and that is substantial enough to prevent gas production.
Hi April
I have come to the conclusion that I will have to dry /condition the sawdust to run it in a gasifier.
If you look on my other thread -Woodgas in South Africa, you can see the youtube links of my system running and my experiment I tried yesterday of sawdust and wood chunks, only to land up with a constipated fire tube.
The sawdust defiantly had lots of power but blocked the tube.
Thanks
Patrick
Looking forward to seeing your photos and video. Sounds like you have been gasifying for some years.
Patrick,
Being newbie here I am not familiar with the web page yet and couldn’t find your woodgas in south Africa thread. Maybe you could just post the youtube link?
1 Like
Thanks Ray
1 Like
Ok, i uploaded some data to my google drive
https://drive.google.com/folderview?id=0B4CL3bqit0osclV1N2NSTjBtVU0&usp=sharing
There are 2 3D pdf’s and a bunch of pictures
@April, i guess your briquette press is on the weak side compared with the ones i use
They use 7,5 Hp with max 150Mp, that say’s nothing
The small one uses 7,5 KWh with 250 Bar max on a 125mm piston or even a 140mm piston = between 30 Tonnes and 38 Tonnes pressure on the briquette.
= between 1,2 and 1,35 tonnes per cm2
short briquettes are more dense, the dryer material gives the better briquettes with less effort.( lignin seals the cellular pores )
The resin from pine wood, needles, cones, does a wunderfull job for briquetting.
@ Patrick,
You can actually look into the 3D model, and if interesting ask for a local manufacturer.
@Wayne,
As for as my knowledge reaches…
The denser the briquettes the more surface is needed to compensate the burning rate ( depth )
Some claims are that it goes proportional.
Would it be interesting for you to test with paperdust briquettes ?
I still have contacts in the states and it could be good, free fuel 
1 Like
April: Up at the top of the page is a “What’s New” button that will take you to a list of the new threads and posts. http://driveonwood.com/whats-new
That said, Patrick’s " Woodgas in South Africa" post is on the Premium Only side of the forums and you won’t see it if you are not a paid memeber.
1 Like
Accounting said the premium membership was in the works. Guess I’ll have to wait 'til it all goes through.
Briquettes are densified fuel. One of our sawdust briquettes is 1 1/2 the weight per volume as wood chunks. So if you add the same volume it will take longer under the same gas production rate to burn it out.
1 Like
Hi April
Sorry I did not know you were not a premium member.
Here is a link to my youtube video for the moment.
Or you just search youtube for woodgas powered sawmill.
Hope to see you as a member soon, there are a lot of great guys on this site with a wealth of Knowlege that are able and wiling to share, and from what you have posted you are the same, you have a little wood gas condensate coursing through your veins
Thanks
Patrick
1 Like
Patrick,
Was able to see the video. Impressive! How much of your sawmill can you actually run off your genset?
We found our 45kW would run lots of our equipment, but our bigger saws and molders required more starting amps than we could produce. Upgrade time or just tie into the grid with what we have. We were trying to avoid all the problems with the utility company. An electrician told us we would need 175 kW. I would have to calculate if our gasifier can actually produce that much gas. If it can, it would be at it’s limit.
Is it going to be worth it to you to invest in a drier for your sawdust and purchase a briquette press? The drier you could probably build yourself.
1 Like
Hi April
I can run all of my saws at the same time as long as we don’t try to start them up at the same time.
My double log edger has two variable speed drives on it so it is the softest starting of the saws, which helps a lot.
Thanks Patrick
1 Like
Sawdust gasifier in Brazil:
http://data.obitet.net/makale/makale/internalcombustionengines/054.pdf
The problems they dealt with would probably be typical. But it really is cute, isn’t it? I like it.
1 Like
Hi April
Thanks for the link, I think I have already read that article. May head is in such a jumble with all the papers i have read on sawdust gasification.
Its a very complicated gasifier, I would like to find or build the WK equivalent for sawdust gasification.
Keep them coming Im sure there is gold out there some where. Or i / we have to make our own!
Thanks
Patrick
1 Like
Back when I worked on a farm, mostly on the machinery maintenance, I was warned about the explosive potential of finely powdered stuff. For example when I needed to do some welding inside a feed grinder. I seem to remember also some kind of experiment in a book when a young’un using flour blown into a cloud to make a bomb.
My point to all this was, I was wondering if a person could blow a cloud of fine sawdust such as with a venturi type sand blaster and ignite it. Kind of like a sawdust torpedo heater or blowtorch.
1 Like
Back in the sixties we installed a lot of unfinished oak tongue and groove flooring that had to be sanded and finished. Those big floor sanders had collection bags for that very fine oak sanding dust and we used to amuse ourselves by tossing handfuls into a bonfire and then walking away without arm hairs and eyelashes 
1 Like
Doug Brethower has this little jewel.
http://driveonwood.com/resources/pdf-articles/missouri-wood-gasifier
1 Like
Hellow Andrew.
A few years ago I built a small square bale burner , looks the same & operates
Like those out side wood furnaces ,you in the country .It would hold 4 small bales.I heated my house & shop with it.I had some flax staw pelipized ,then I made it into a powder . I took about a walnut size amout and through it into the
Squirrel cage combustion fan while it was operating. Guess what ? Bang.My explosion doors opened up & the blast of air through me back on my but.Will never do that again.
1 Like
I played with powderd flax straw ( up in our country we have tons every year) they tell me it has same energy as soft coal.it can be put into pellets , but very dangerous to do ,because of a spark. I was wandering if the WK could some how be made to do it ? Would be nice ,because we lack a lot of trees.
Calvin
1 Like
I tried to open that PDF at 10:20 Central time and this is what I received.
Forbidden
You don’t have permission to access /sites/default/files/pdf/pub1353.pdf on this server.
Apache/2.2.3 (CentOS) Server at driveonwood.com Port 80
1 Like