Add plenty of air holes for the flare torch. Got any pics of the nozzles?
To answer the radiator question, if the gas feels like it’s about the same temp as ambient you’re fine.
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Congrats Derrick another step closer, and soon you will be eating lemons before you know it.
That flare does look rather good though from what i can make out , i hope that your not trying to run that inside of your workshop though .
Dave .
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Double what Dave said, make sure you have a good draft. Woodgas has a lot of Carbon Monoxide.
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Could your fan be too strong so the flame doesn’t stick? What does the gas look like before you light it?
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I should have taken some pics of the nozzle ring before I installed it. Later today I’ll see if I can get some pics if the coals burned down below it or maybe I’ll just pull it out and take a few pics. Basically I did a very simple design with 4 “T”s and 8 “45”s then I used plugs drilled out as nozzles to screw into the Ts.
I had thought about bending pipe or doing a welded ring, but frankly, while the way I went probably cost me more in fittings, it saved me a lot of time and I didn’t want to get wrapped up in a long fabrication project - I wanted to move on and see if I could get this thing working, so I took the more expensive, but quicker and simpler route. In any case, the way it is installed it is welded in through the hopper and then joined with a union inside the hopper so I have set it up in such a way that I can easily modify it or change it out for an upgraded version in the future if I want to.
Also, as far as operating it in the garage - it is well ventilated, where the pic was taken was actually on the outside looking in to get a better picture of the flame - I have two big barn doors and whenever I do a test I roll the unit just outside these doors and I also have a big exhaust fan blowing everything to the outside.
I used to roll it all the way out into the yard, but then have to fix it and roll it all the way back so now I don’t go to far from the garage in case there is more work to perform lol.
I have often wondered about that too Jan, it does draw pretty good and I don’t have a rheostat installed to slow the fan speed down, but what I have tried to do to compensate is to close the valve on the torch and not allow a full volume to just blast out of there so that I can slow the flow of the gas that way. The gas looks like just a light haze before I light it.
I didn’t think to check the temp there at the flare, I wish I did - I will when I run another test later. I did notice however after I added the nozzle ring that the radiator itself was a lot warmer to the touch than it was before but I ill check it at the flare later when I run another test. If that does turn out to be the issue, can I just add another second radiator inline after my medium filter?
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Adding another cooler is fine, you might even get more water out of the gas. In a lot of our vehicles we make a water trap to collect any extra condensate before it goes into the engine, after the filter.
With a generator setup as long as you’re okay with the space it takes up you’re fine.
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Also the ring you described sounds good! The cast iron nozzle tips will last a long time.
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Excellent, that will be an easy fix then if that roves to be my solution. I’ll do a little more testing later and let you know how it turns out. I’ll also try to post some pics of the nozzle ring.
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Just looking at your pictures again, you definitely do need some more cooling. I would make one using 180 degree bends that snake down, to give the gas more dwell time in the cooling pipes. I don’t think it’s keeping the flare from staying lit though.
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In the sanitary water heaters, spirals from pipes are installed, in some also 1", if you have the opportunity to get a used piece,…
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So here are some pics of the nozzle ring, it is constructed of 4 “T”s with 8 street 45s and a few close nipples to go in between the 45s. The only place I had to get creative was the air supply T- there was not enough room to screw it in with reducing bushings, so to solve this I cut the T shorter and cut the threaded ends off two of the street 45s and reversed them letting them free float inside the supply T, then I just welded the 45s to the corresponding Ts
Also, what do you guys think about PVC as a material for a supplemental radiator?
I know it won’t conduct and transfer heat as good as metal, but I have a ton of pex pvc pipe in a coil and I could easily plumb in a long run of multiple coil loops - what do you guys think? I was also thinking of maybe plumbing in something inside of a barrel of water so that it is jacketed with water?
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I only use PVC or plastic after the cooler and filter. It’ll cool it somewhat but it would be better to use steel.
You can get the galvanized fence post at Lowes Hardware, for your gasifier you could use the more narrow diameter stuff like the 1.625" that they call 2 inch.
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One more thing, it helps to fill the gasifier up way above the nozzles with charcoal on a fresh run. If you don’t have enough ashes to prefill all the voids, the smaller pieces of charcoal will take it’s place so you’ll use up a bunch seemingly.
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I don’t think PEX will work well. ID too small to allow sufficient gas volume but for a stationary gasifier I think the idea of piping a grid in a barrel of water to cool the gas is a good plan. Something I’ve always planned to do when I get to building a downdraft. Of course the cooler piping will have to be cleaned out periodically so you would need to have the bottom of the manifold sealed and protruding from the bottom of the barrel.
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Thanks for the pictures DerrickD.
Good effort but I think your results will be too limited.
Think of it this way. Your only active area/volume will be from the air entry tips in a cone downwards. In all of the charts and graphs this is what you have to imagine.
CodyT here on your topic showed a downward picture into Joni’s gasifier that shows this fairly well. #152
Your active area-volumn nozzle tip to tip and downwards is very small.
And you have inactive areas in between these extending inwards four nozzles. Worse you have a smokes by-passing areas around your whole outer ring and wall gap.
To make what you’ve made up so far work as well as it can now make up segmented sections SS slope of 30-60 degrees angled filling in down across your pipe ring with four tongues extending down inside between those between nozzles dead corners. Force all above made early-gasses and downward settling fuel chunks only to go through the center active hell.
This will give you a smallest gasifer possible in your can envelope. You will have to chip/chunk smaller for that.
Later you want to go maximum possible in your can envelope make up another larger diameter pipe ring to fill farther outwards with a larger center active area.
Use eight double female threaded pipe 45’s connected with longer close couplers in between seven of the segments. As you proven; an upward Tee between in one segment. Welded to the two 45’s or tight close coupled if thier is space.
The actuall air nozzles can be just holes drilled into the thick-walled, cast 45’s. Angled upwards as Joni showed ~20 degrees.
Really fancy elaborate: for that would be drilling and machine thread tapping the holes (or welding on nuts over the holes) in the 45’s and using center drilled out stainless steel bolts as your nozzles as some do. Then adjustable and replaceable. But protruding inwards back to a smaller cone-volume active area.
I think it would be far easier and cheaper to just make up a new pipe ring as the previous burns out.
Regards
Steve Unruh
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Well here is my latest update and I wish it were better news. I ran another test, but I did not make any improvements to my radiator yet - this time I was just curious what the output temp of the gas was to see how big of a difference there was between the gas temp and the ambient air as Cody said. Turns out, the gas wasn’t all that much hotter than ambient - a little bit, yes but not by much.
So while I will likely have to add some more radiator space, I am also wondering a little bit about my blower fan because I don’t think I ever really asked this question. My blower fan seems to be pretty powerful and is really drawing a good flow though - is this good? Or is it better to have less suction and a more gentle draw? Does this even affect the output at all?
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It depends on the size of the gasifier, but the more CFM it can pull the faster it gets up to temperature. Try pushing on the system with your blower, and test the flare. Just plug it up to your nozzle air entrance.
If you see smoke wisping out of the lid don’t worry, that usually happens with positive pressure.
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I don’t know if you’ve seen this in the library, but with these dimensions, you get a pretty good unit.
As Steve says, you have very small diameter between the nozzles.
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I don’t remember if you build fema-style? In that case i could be useful with a variable fan, start with slow speed and slowly increase during heat-up, just something i discovered as helpful when going fema, or fema with nozzle.
I believe this helps the glowing zone to raise in the firetube? I dont know if others has experienced the same?
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I did see that Jan, thanks. I think Cody may have recommended that early on as well.
I was trying to the best of my ability to mimic those specifications, but obviously my attempt was not perfectly in line with the specifications. I might have to rework my attempt at a nozzle ring in the long run.
And yes, Goran, it started out as a FEMA style project and just sort of morphed through many different rebuilds to try to get it to work - I guess mine would sort of qualify as FEMA with nozzle, so perhaps I will put a rheostat inline to slow my fan down at startup if that is something that you found helpful - its worth a try for me!
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