A Wood Gassifier ... My next project !

[Bob]

I emailed a fella off that site Manta and he answered a bunch of my questions and told me to sign up on the woodgas forum on yahoo.com... which I did...and so I read a bunch and think I know why the truck didn't run on woodgas now... the heat was far too low in the producer to have worked.... so I have a bit more work to do...
I am going to take off the stainless steel bowl I am using as a grate and replace it with a plate I will preferate with 3/8" holes ...
I may also reduce the opening on the fire ring right now its about 12" which is a bit big
and if it were smaller it would concentrate the heat better and it would also move the distance
of the grate away from the fire ring a bit more also helping to establish the ZONES of certain degree of burning up that the Producer SHOULD have,....so I may destroy another propane tank shortly ! LOL
....at least now I have some idea on what I SHOULD do to make it work.... I admit I was at a loss before ! LOL
....
Bob.......

[Bob]

Boy in the last few days I've been buried in information about what makes the burnable gas in a Woodgas Producer!... Oddly enough its Mainly the intense HEAT and WHERE that heat takes place
...In My producer the intense heat will take place adjacent to the air holes in the fire ring... and that is too LOW.... it should be a good 6" higher than that so it would Pre-cook the other wood.
Sense the air holes are so LOW on the fire ring I need to remidy that soon....
I could cut the whole fire ring off, flip it 180 degrees and weld it back on and have the air holes on the top of the ring... which is a good place for them... but ash would fall in the holes and eventually plug up the works... so 90deg elbows should be attached to stop that and force the air to the center.
...this is all quite attainable, allot of work but still its do-able!
 restricting the size of the fire tube and fire ring, after the fire ring may indeed increase the velosity of smoke and gas and there by make it a blast fernace in effect...which is what you want
but restricting the size also lowers the volume of volitle gasses I would get off it as well, so it looks like a dammed if I do and dammed if I don't sinerio..
 although many of those fella's on the woodgas forum on Yahoo have only a 6" or 8" opening and they run v8's on their producers.... so Maybe I am worried about nothing <GRIN>
at this point I am thinking that increasing the velosity is more important than the diamator of the burn area...
... And I am not the only one that used a car Rim in my producer burner, another back woods fella has made 3 such producers for his vehicles...he is quite a master at it !
....
so I think I will Hack off the rim...er FIRE-Ring and while its off weld up all of those holes but 6
or 8.... and then weld 1/2" pipe elbows over the holes and screw on 1/2"x1"close nipples and an end cap with a 1/2" hole in the cap on each one... this will force the incomeing air into the center of the burner and create a super hot zone...
then I'll weld a short cone on the other side of the fire ring, that reduces the over all diamator to 9" or 10" down from the 14"it is now...
 and I'll see if I can BOLT the fire ring back on to the fire tube so that in the future if I want to change something I can simply take it off and work on it....(much better than having to cut it off again ! ) hehehehe
...
that SHOULD cure everything but the Grate problem and for that I will cut a 14" diam circle from 1/4" plate and ring it with 1/8"x2"bar stock, drill a zillion holes in the plate and call it my new grate and hang it by chains from the fire tube and put a loop on the side of the grate so the shaker lever will attach and shake it.
...I do not relish the idea of drilling all those holes... so I may just make a bar-stock grate and forget the plate altogether ! as long as the bar-stock is 1/2" apart and no further it should be superior to a flat plate.( till they warp out of shape ...so they will need side ways supports ...and allot of them.)
...
now all I need is GOOD weather.... order some up for me please...I could use some sun shine ! LOL
...
Bob......

[Bob]

Here is a pic of the changes, I made them on the drawing on GMAX but I am not sure I like how High it puts the air nozzles... I may go with straight pipe instead and lay them horizontal.
...
Bob.....

[Bob]

I'm still knocking around ideas, I may opt for Charles's Truck rim design and Hack my rim off and put on another... I think it would be much easier than trying to re-work the one I got.. I put a bunch of welding rod into it ! LOL !
...
Bob...

[Bob]

Well I did cut off the old fire ring and I'm getting ready to "BOLT on " another VERSION...hhehehe
... I Have Opted to patern my new design after Charles Purdy's version of the "LaRosafier" as I think his is the sanest of all the designs I have seen yet !
 its simple and stright foward...and no where like the FEMA plans that I was using before
sense a 13" car rim fits nicely into the 20gal propane tank bottle TUBE I have as the "fire tube"
all I have to do is mount the Rim plug a few holes where the lug nuts went through and on the side there are a few slots that need sealed up...and then weld on a new "Fire tube" to the underside of the rim... I cut apart a air tank that used to be on a Diesel and am using it for the 6.5" diam tube welded to the center of the rim on the bowed Out side of the rim... the bowed IN side of the rim will be the burn area...and should be covered with refractory cement... but I may use cat litter clay and hope it holds up ! <GRIN>
  the BOW-in on the rim faces UP and the welded in tube on the underside faces down and its 7" long
a small grate will be hung under this opening ...this tube is actually where All the Cracking of the gasses occur at....well the main burner and the tube...because it holds the charcoal and the air is drawn through it ..forcing the reaction to take place because the temperatures are so very high.
...
I have some patch work I need to do on my work today as I got a bit too carried away welding!
but I did get allot done and I hope to have the new burner bolted on tomorrow evening !
it won't be done because I have 6 air jets to weld in there yet...but that shouldn't take too long once I have it all marked out where they go.
...
so I still have a long way to go ,but I'm about 1/2 way through the new burner...
I just wish I had a piece of 14" tube at hand so I could face that new rim with... but it looks like I'll have to disect another propane tank for that part...unfortunately....
I plan on tripling the capacity of the inlet air by using a 3" pipe instead of a 1.25" pipe...
this will give the needed air flow for those high temperatures.
...
 and something of interest.. when these burners are going and working correctly there is no woodsmoke coming off them... no smoke to see at all but the heat is very high enough to blister high heat paint in no time!... I thought tat was kind'a strange...but the heat is so high (1200 to 1700 degrees)
that the smoke particles are incinerated....I guess !
 its really kind of weird, you can tell if a Woodgas generator is working right by the absense of smoke...if its smoking something is wrong ! HAHAHAHAHAHHAHA
so they really are pollution free ! ( or darn close to it!)
...
Bob......

[Bob]

after more reasearch and talking with others about the woodgas beastie I have desidedto change my producer's fire ring to something like this...
...I already have it 3/4 done...
and I need a vacume cleaner for the blower motor I find out ! hehehehehe
...
Bob...

[Bob]

 I have been working on my Woodgas Generator Drawings for thew past 2 days sense its been raining out side... I have made a few improvements and updated the drawing to reflect what has been done lately...
 this woodgas generator should without a doubt work very well... and I hope it will produce enough gas to power the V8 in the Dodge truck... it should as other generators a bit smaller power larger engines, so I think its got it covered to say the least! <GRIN>
... I got all 8 air jets welded into the rim now and am in the process of putting on the clamping flanges so that I can remove the Hart of the burner at some time in the future if needed... I welded the last one and had to cut it off to make these changes... I don't want to have to cut it off again!
(live and learn!) this will force me to use some furnace cement sealant around the rim to make a good seal, but that part is relatively easy with a caulking gun and the high temp sealant.
...
I've also added a diverter to the inside of the rim (almost invisible, directly behind the air connection tube on the rim) to help direct the flow of air around the rim properly... I think it will help with the air flow and boost air flow through ALL the jets. I will make this from sheet metal and cut to fit the inside shape of the rim and then tac weld it in place (not done yet on the real thing)
...
I have also "massively modified" the air connection tube(purple) spreading its mating surface over a wide area, so the restriction is less.  This will make a big improvement in air flow.... I hope.
...Although I  have yet to do this on the "Real thing" I am sure the extra work will prove worth it in the end...
...the round yellow see through ball is supposed to be the fire...
...the 3 levers are, 2 latch levers for the long wide ash cleanout door for a good tight fit,
and one grate shaker lever....
....

here's the latest drawing...



Bob...

[Bob]

Well, I finally got to weld a bit on the woodgas generator.
 I got the tangs welded on to the rim so I can bolt the rim on instead of welding it on... and the big hole for the air intake blasted through with the arc welder.... (that still needs allot of clean up work done on it)
 I need to finish up the grate and extend the center rods up to the hole in the center of the rim... (not in the drawing, but I'll add it later.)
then drill the holes for the bolts in the tangs and install the bolts.
weld on the intake pipe and extend the bottom of the intake pipe with another piece of the same pipe, to get a better air flow in there.
then make the diverter and install it... .
chain up the grate and then assemble it, Re-seal the thing entirely... and then round up some real charcoal and fill from the air jets down... then add my wood and try it out
....
so I still have a bunch to do... but I'm getting it !
....
Bob.....
 

[Bob]

Here's a new drawing of my Gassifier...
if anyone cares <grin>
...
Bob...

[Bob]

I got a bunch done on the gassifier so far today... and am Hopeing to get the grate on and put it back together this afternoon ! but its clouding up and looking like rain so I may not.
I got the air inlet on and fitted good and extended the side of the tube down to help get more air flow through the jets...
at a rough guess #8 3/4" tubes are about 6 square inches of area, and my 3" diam inlet pipe is about 9 square inches so it should work really good....
 ....
 I need to check out the old shop vac I have in the shop and see if I can salvage it for use as a high powered fan for the gassifier... that is one of the things the boys do on the woodgas forum on yahoo they all use big shop vac or vacuum cleaner type motors... and they work very well...
  I will try it with my heater blower fan that I have already installed on the unit but I suspect that I will need more air flow in the end.
...
I also think I will take the heating plenum out of an old gas furnace I have out yonder and see if I can use it as a radiator to help cool down the hot gasses.
....
Bob.....

[Bob]

I got about an hours work on the gassifier today,not much but I got 2 things done the intake tube is in and siliconed up with high temp silicone and  I plugged the old intake hole that was too small  and positioned on the side....
I put the intake above the Ash door as its easily accessible there.
...
so its ready to fire up now ...soon as I put the hopper back on it... but I may leave it off for the initial burn in  because I am just going to burn wood in it to get the bed of charcoal I need to have in it and then I will try to run the truck on it after that is done
 no sense in trying it without that needed bed of charcoal because without the charcoal the gasses won't "Crack" (been there done that already!)
....
 the rest of my day was spent fighting my chainsaw... it quit and I dunno why...I think its the CDI unit.... hope not because that may cost more than a new saw will ! HAHAHAHAHAHA
....
Bob......

[Manta]

Bob,

Watched a program the other day that showed how a guy in Scotland was smoking his fish. The smoke producing unit was about 15 feet from his smoke-house.  Connected by a largish bore tube;  looked about 8" diameter.  He explained that this was to cool the smoke before it got to the fish.

Maybe that is the way to go.

Manta

[Bob]

Manta:
 Many of the guys have coolers of sorts pn their wood gas trucks to make the woodgas denser by making it colder... I don't happen to have one on my truck yet, but I may have to rig one up in the future... i figure for the amount I'll be using the truck it don't need it ! LOL !
if I find I use it allot I'll put one on it <grin>
when you "Smoke" Fish or anything else for that matter, its best to keep the temp of the smoke house below 120 degrees ... the idea is to let the smoke "CURE"it , not "COOK" it!
however there is a drying out process that is also needed when "Smoking" meat so it really depends on what you read or who taught ya to do it ! HAHAHAHA
there is as many ways to Smoke Meat as there is ways to Cook it!
I prefure the Dried out method... it lasts much longer and makes great Jerky!
I have a Smoker that I picked up at a yard sale that I have never yet used... Hope to some day but buying meat is something we hardly ever do... last time I made Jerky it turned out so good that by the end of the week it was all gone and I made a good 10lbs of it ! HAHAHAHAHHAHA
... "Smoked Rainbow Trout" is one of the best tasting things you'll ever eat as is bar-b-q'ed trout.... but I haven't tasted that sense I was 20yrs old ! LOL
....
Bob...

[Bob]

I made a post on the woodgas group on Yahoo that I think bears repeating here....
I'm far from an expert on this woodgas stuff but it seams to me everyone is making it SO darn HARD!
....
  ITS NOT Rocket Science ! not by a long shot.... the idea is simple... You build a fire in a bucket or drum, get it going good and put a lid on it and the flames go out.... sense the flames no longer consume the burnable gasses they can be siphoned off to run an engine....
 yes there is more to it than that but that's it in a nut-shell !
 to me there are far too many people wondering "where can I get plans for a woodgas generator"?
and the FEMA plans actually are the poorest example out there.... but their just about the only ones with enough documentation on them so you know what your doing..... that's why I based my design off of the FEMA plans to begin with....
 However I quickly learned that not only was the FEMA plans very Poor plans but that a simple modification would make it better... a reduction zone....  so I added a 13" trailer rim into the mix and tried that.... I feel certain it would have worked now the way I had it, but I didn't give it a chance, I changed it again into a Sort-of "La'Rosafier" by taking out the trailer rim and  adding a car rim and a short down tube under the rim to hold the char.... I also added Jets or tubes for the air to be drawn into the "hot spot"....
but the basic idea has alwayse been the same...  the only real change is pulling the smoke through the char ,where before it would have just been in close proximity... because I learned that it takes extream HIGH tempitures AND CARBON/Charcoal for the gasses to "CRACK" into flamable, useable gas
....
so I think anybody can power an engine very easily by simply following a few simple rules....
realising that the engine is going to provide the air flow through the burner.... so SIZE MATTERS!
if you make the gassifier too big the air flow through the fire will not be fast enough to generate the intense heat needed to "Crack" the gasses... on the other hand if its made to small there will not be enough gasses to RUN the engine.... But in my mind its better to go too large than too small
because there are tricks you can do to get the temp up if needed. but there isn't much you can do if the gassifier is just too small to run the engine!...except build a bigger one!
...
 I outlined a idea of a 5 gal bucket with a car rim on the top (dish/lug holes, down) and a 3" or 4" diamator tube welded to the center hole pointing into the bucket, about 8" long.... and a small grate under that tube....
thats all you need !.... the rest is frills...  you need a way to light the fire ofcorse and a way to clean out the ash in the bottom... but that should go without saying <grin>
 Now with another bucket on top the rim acting as the fuel hopper your ready to go... (except that the bottom bucket needs a hole in it near the top so you can draw out the smoke)
... this SHOULD run up to a 2 or 3 cyl engine....and perhaps a 10hp or 12hp single...
its a might bit big for a 5hp B&S, to be sure, but it may well even work for that if care is taken to make the air velosity going through the burn chamber as High as possable.( that's kind'a hard when the engine is real small because it doesn't draw in that much air to keep a good hot fire going)
....
ok now that you know the idea it should be a fairly simple matter to make something up that does what you want..... you don't Need plans because its so Simple... but hardly anyone will ever explain that.
 They'ed tell you for hours on end how long it took them to get their units working and working good.
and How they did it, step by step.... and unless your making a gassifier for the same engine they did its really not much use to you...
  Now granted I have yet to run my truck off of Wood gas, I am waiting now for the fuel supply to DRY OUT ! LOL.....but I have no fear that it will work just fine .... I am sure it would have worked the way I made it first off, except I didn't know the unit had to have a bed of charcoal in it to work!
other wise all it makes is smoke ! ....I tried Bricketts thinking that was good charcoal... but that is NOT the same at all... it needs burned up wood chunks, ashes are fine Grey stuff, charcoal is the black hunks of ash.... that's what you need...and you need a bunch of them !
so you have to fire up the generator and let it burn down 2 or 3 times until you get a good bed of charcoal.... then try getting the engine to run on it.... try to do it before that point and all you'll get is frustrated!
....
Hope this helps someone trying to get a handle on WOODGAS....
...
Remember I'm no expert on this... so keep it in mind!
...
Bob......


 

[Manta]

Bob,

you might want to take another look and the Lister site. (your reply 105 above).

Here is a message 'borrowed from Ken Boake.  Seems they have got a Lister running on wood gas.

MK,

There will be full parts list, drawings and "How To" released through AllPower Labs.

We ran it again for 2 hours last night, having made some retardations to the ignition timing. About 5 to 10 degrees before TDC was about the sweet spot.

We had it lighting up 2.75 kW of halogen lighting, but it kept popping the 20A breaker when we tried to load it more. It had plenty of pull left when we revved it.

Unfortunately we didn't have a power meter available or we would have got some more accurate measurements. We hope to have some confirmatory figures soon.

Sadly, I fly back to London later today - just as this project is getting interesting - however I am leaving it in the capable hands of the good folks here, to push it forward and do some real scientific method on it, working out the efficiency, fuel economy, heat budget etc etc.

We made a linkage to allow the Listeroid governor to work the butterfly valve in Andy Schofield's gas carb and this needs a little more work and proving.  However, as we have an Arduino timing the spark, we might just chuck a R/C servo on the butterfly valve and have the Arduino control the throttle.

The Lister was running sweetly at right on 600rpm,  - when we pushed it to 620, the natural resonance of the skid we were mounted on caused everything to start shaking - so we stayed at 600 and made power at 53Hz.

I took a load more video last night which I will get up to YouTube.

If anyone is passing through northern California, and wants to see this running and have a tinker - I'm sure All Power Labs would be happy to accommodate you.  Getting this running optimally would be a great college vacation internship project.  I expect to be reproducing the set-up this summer in my workshop back in London.

This could be one of the best things happening to a Lister, since 1929  ;-)


regards,



Ken

Should stop you getting bored.

Manta