Hey guys New to the gasifier world was looking for some advice on building a gasifier to run a 4000 W generator. I have started construction on mine. I am using 2/3 of a 100 pound propane tank to make a down draft style fully welded to stop/minimize air leaks. Any advice while building? I have watched lots of you tube videos on fema type down drafts and seems straight forward for the most part. But I’m afraid of the blow back and the thing exploding.
Thanks for any advice and sorry if I wrote in a wrong format as I am new to forums/ chat group’s.
Welcome to DOW, Morgan!
I am sure by now if you have done any reading on this site that you realize that you will be getting somewhere around 2000 watts on woodgas vs 4000 watts on gasoline, Are you working off plans as far as sizing your unit? A sketch of your plans would be helpful if you are asking for advice. Many experienced wood gassers will tell you to stay away from the Fema design if you value your engine.
Hey Morgan, you have come to the right place. I would also suggest you read some of the threads on here - specifically about running charcoal. It is hands down the easiest place to start out on the woodgas adventure, and it is well suited to small setups. You do have to put some work into making the char, but you will find that it ends up being easier to do on a small scale than making chunks of wood.
If you read some threads and start asking questions, this group will amaze you with their knowledge and willingness to help you succeed. Keep us posted!
I’m more or less trying to get my feet wet on this and learn from it. I was just scared of the explosions part. I do understand that big gulps of air mixed with gasifiers don’t mix well. As well as to big of fan pulling in air can cause issues. I don’t want to use an oil drum as I think there to thin so I went with a propane tank with an 19 in long 4 in pipe, with heavier 8 in shaker bowl. I welded in an 6 in flanged clean out again built heavy and have it welded in. That’s kinda where I am at for now. I like the char idea as well but would have a hard time getting char made as I am in a city and the FD has strict bylaws.
I’m more or less trying to get my feet wet on this and learn from it. I was just scared of the explosions part. I do understand that big gulps of air mixed with gasifiers don’t mix well. As well as to big of fan pulling in air can cause issues. I don’t want to use an oil drum as I think there to thin so I went with a propane tank with an 19 in long 4 in pipe, with heavier 8 in shaker bowl. I welded in an 6 in flanged clean out again built heavy and have it welded in. That’s kinda where I am at for now. I like the char idea as well but would have a hard time getting char made as I am in a city and the FD has strict bylaws.
Hello, and warm welcome to the DOW. Since you want to raw wood gasify fuel a 4000 watt engine generator this puts you in the SMALL ENGINE classs. Go to the top tool bar here on page. Open up the stacked paper icon. Find the Small Engines sectiom. Deep read for topic projects that most match yours. All of your questionss been asked, trialed out there. You have the system flows basics diagramed useabe. However hard expeiences shows for best no-tars results with the longest duration use with the least hands holding your gasifier reactor internal details will need much more thought out requiring more building steps. Regards. Steve Unruh
Hi again. To help you sort the many, many Small Engine topics-projects look for those that will use woods prepared as you will use. Urban trees limbs cut onto round section billet-bits. Versus kiln dryed stabilized shipping pallets sawn cut into chunks. Versus arborists ALL tree brush grind down full leaf needles mixes screened sorted for the minor percentage ofsmall systems useable true woods. Small systems are very fuel input type finicky. Only look at systems that have accepted the necessity for zones establishing air nozzles. Only look at systems the builder took it into actual loaded running. And then did use it for real. One personal electric engine genetator advantage to tap is the engine gen heads abilty to dry and pre-warm incomimg wood fuel bits with its hot dry blowing air and close coupled exhaust heats. Alwaus puttimg in sub 10 percent moisture woods allows the hopper down system to be super simple. S.U
Hi Morgan,
Welcome to the gasifier world. Check out, “My first small engine
run” in the Small Engine section on this site. Lots of how I did it
information that might interest you. Pick my brain if you like, I
think there’s a chunk or 2 left.
Pepe
Thanks guys for the help, I think I i’ve already change my mind I’m going to make an imbert style just to make things easier/ cleaner for running a motor, i will keep you guys posted on my build, what would u guys suggest for filter media? This is what I started on so far for the down draft but will cut in and flange a bigger imbert style. Might as well make it right the first time in regards to burning clean.
Thanks again
Morg
Hi Morgan:
Filtering I have evolved to favor either layered sheeps wool loosly woven fabric. Or chambered stuffed all sheeps wool boots socks. (A Gary Gilmore recommendation)
The sheeps wool has good enough particulates capture. Good enough warm temerature durability. Excellant condesate miosture durability and condendate wettened still gasses flow. And can be wet soap and water cleaned and reused.
And any filter shedding sucked into the engine wiil not abrade or sticky melt damage.
Here USA this loose weave true wool in availabe in thrift stores jackets, pants and skirts.
S.U.
Thanks for theFeedback and recommendations what are your thoughts on filtering should I go with a tri filter set up or a single filter, I have seen both in YouTube videos and both seem to work. I like the idea of pvc for cleaning purposes and it should hold up really good to wet conditions and tar.
Your usage will determine your stages of needed filtration.
For IC engine fueling IMHO only a single stage is actually needed.
Useing you will find the need for a still-hot ash corse soots separations system area.
As gases cooled to condendates dropping out: a condensates collection area.
Theses are also gas cleaning steps.
“Less, is More” So long as the Less is experiences taught intended.
To add, think of filtering as a refining process. Different things happen at all levels of cooling. Tar is nearly impossible to filter as it is a gas state under vacuum due points very on grade level. Early cooling stages you will note just water dropping with out tars and can even be with out soots. Color can sometimes be clear, amber, black or look like grape koolaid. Your later stages will the drop the nasty tars if produced at varying levels. To filter tar you can filter at the micron level. If you ever followed I was very anti filter media as all the filters I used in the early days would simply rob power from the unit. The thing I learned is ash debris was very little to non existent and with out restriction the gasifier can breath better and make clean gas. However, thats not always 100% and I have since changed my thinking. I now use bag filters that filter at the micron level and some filters have up to four stages now. New thinking is if the gas is clean well then the filter is going to stay clean and the bag filters breath with very little restriction. However, if there is tar produced these filters will knock it out. I design now so that at least one filter will remain clean in any event. If this is not the case then we add more filters until it is the case. Only takes one tar event to make a bad day. However on a small engine its really not a hard fix but still a PITA.
So I guess the point is build it, try it, the ask if its a enough. If not add more.
Hello Morgan, Sorry, I must have missed your introduction to the site before. Welcome to DOW, the most helpful wood/char gas site in the world. You came to the right place, and you already have some of the best giving you their ideas.
With wood, smaller is harder (more difficult). Hotter is better for tar. Obviously charcoal is easier. But you have the right guys on it.
So when u guys are talking bag filters, what is being used and how is it installed, thanks for all of the feed back you guys are throwing my way much appreciated.
