Making my simple fire gasifier

Brian , when you first load up that drum with glowing charcoal leave the lid loose don’t what ever you do make it air tight to start with wait till the coals stop glowing before sealing up the lid air tight ,other wise it will burn up any oxygen inside and create a vacuum and collapse the drum .
Dave

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I don’t have the clamp for the barrel’s lid and it doesn’t have a gasket so it won’t seal completely air tight but good enough to keep the coals from continuing to burn.

I misjudged the angle it needs to get the charcoal to go down the screen so this ended up shorter than I intended but it separates the finer (1/2" and smaller) from the charcoal I will still need to grind. I’ll still have to screen the fine stuff once more to get the ashes and biochar out.

This screen can also be used to get the rocks and bigger clumps out of my compost pile.

This is the fine pile from yesterday’s barrel of charcoal.

This is what I got just from separating the charcoal without any grinding besides breaking it up with a shovel. I’m figuring there’s 2 hours worth of generator fuel in that bucket ready to use. Probably a gallon worth of biochar. That isn’t even counting the 3 or 4 buckets of bigger charcoal that could either be ground finer or saved for forge, foundry, or BBQ use.

The better barrel to put the glowing coals into was the key to having a practical system for making my own fuel. Gotta go find a lemon now.

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Brian,
If you are using a 1/4 inch (4 mesh) screen for the fines, you will be ok and reclaim more engine fuel using 1/8 inch (8 mesh) screen. That is what I use and haven’t noticed any negative issues.

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The hardware cloth in the new screen is 1/2 inch and my little screen is a little over 1/8 inch. I would like to have 3/4 inch as the biggest screen but I don’t have any that size. A few bigger than 1/2" pieces got mixed in with this engine grade bucket which should be fine but I think I could recover more of the bigger pieces to mix in if I get a 3/4" screen and eliminate even more grinding.

I’m still researching and hunting through my scrap trying to decide on a down draft charcoal (or wood) gasifier but my simple fire gasifier is working good enough that I’m not in a big rush to use up my scrap until I decide exactly what I want to build.

I have a 20# propane tank sitting here just waiting for a use but it’s starting to look like a filter for the simple fire if I can figure out a good way to seal it but still be able to clean or replace whatever filter material I use. The bucket filter I have now is working but the 20# tank might work better if/when I put this on a base or cart.

garage54

Thinking something like this might an option for the 20# tank. Maybe upside down so the threaded opening could be used as a drain.

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My grinder batteries went dead but got the propane tank cut.

Kind of crude cell phone drawing but this is my plan.

The tank will be upside down so the threaded part where the valve was will get a 3/4" pipe plug to drain any condensation or to drain it if I just wash out the filter media.

It will be raised up to access the drain but I won’t know the length of the legs until I get it together.

I want to go out of the gasifier, through the condenser, and then into the bottom of the tank (formerly the top). The gas outlet will be on the removable top section where I’ll hook up the hose to the engine. I thought about making the gas outlet at the side (and still might) but it will probably be a plastic hose so being on the removable lid shouldn’t be a problem.

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I discovered a problem with my plan. My nozzle still isn’t easily replaceable but that can be fixed with Tom’s suggestion. The problem is the way I have been cleaning out the charcoal is to just flip it upside down. I won’t be able to do that if I keep adding to this or mount it on a base.

Here’s one solution.

The link in that post goes to some pictures of Giorgio’s clean out port. Large pipe fittings and pipe caps are expensive and I can’t tell for sure but it looks like Giorgio’s version isn’t threaded. Where my clean out port would go is in one of the hottest places on my gasifier. Would woodstove gasket rope and high temperature silicone handle the temperature at the bottom side of my gasifier? I’m thinking a section of square tube welded on the side unless I find something better.

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If the nozzle isn’t pointing directly at that area, and you leave a gap for ashes and charcoal to help insulate you’ll be fine.

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I have a couple of simple fires without any clean out as well Brian. They are small and I just suck the char out of them with a shop vac when I want to clean them out.

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Back to burning liquid fuel for my generator.

Probably still some life left in the nozzle but it did melt.

I chopped a hole in the side to get to the nozzle and as a clean out port. My square tube was only 3 inches so I decided to build my own.

Should have used the grinder instead of the torch to cut the pieces but…

Hours later it’s getting closer. I still need to figure out how I’m going to make a door for this and will likely have to do more grinding to get the door to seal.

My water trap jar came off and might not go back on. It was hard to get it sealed airtight and the last couple runs there was only a few drops in it.

I still want to turn the propane tank into a filter but hope to get this simple fire gasifier working again so I don’t need to burn gasoline to do all the grinding, cutting, and welding it is going to take.

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Make a piece with double lips to act as a channel for the stove rope.

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I won’t know if this works until I get some stove rope and more silicone but it sits on here without rocking.

I still need to clean it up and round the edges but I want to see if it seals before getting too much more work into it. My homemade box was welded inside and out but I’ll need to check it for leaks too.

Looks like I used about a pound of flux core welding wire today but I have close to a 5 inch square opening to reach inside instead of just using the 3 inch square tube I had that I was thinking of using.

I only tacked the lip for the stove rope. Hoping the silicone and rope seals it good enough. Hopefully I can be back running on charcoal gas soon.

This will make cleaning it out and changing the nozzle a lot easier.

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on my gasifiers i do not use silicon for the rope, i have the double lips higher, so the rope stays from alone inside…on the two ends of the cut i make some windings of adhesive stripes…til now the stripes are keeping up with the heat…i tried this because not having silicone here…

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I found an old piece of stove rope and had a partial tube of silicone left so I put it together.

I figured silicone and charcoal dust wasn’t making a big enough mess so I smeared some grease on the surface of the new box.

I’m hoping that stops the silicone from sticking to the surface so it will come back apart. I reinstalled the old nozzle first so, if I don’t have any leaks, I can get this running again soon before seeing if it will come back off without messing up the seal.

It looks like it could work. I was worried I didn’t leave enough of the bolt sticking up on the right side.

Will have to wait for the silicone to cure before testing it. Half of the tube I used was already solid so I guess it’s a good thing I used it up instead of trying to save it.

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A lot of us use cling food wrap or wax paper between until everything cures.

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I got impatient and tested the gasifier for leaks and didn’t find any so I filled it back up with charcoal and run the generator until it shut off.

Used almost half the tank of charcoal so it probably either got too much of a burnt pocket of charcoal or it just didn’t have enough charcoal above the nozzle to produce good gas.

EDIT: Just going to slip this in:

The gasifier was really hot so it was probably time to shut it off anyway but I got most of my new filter welded up using charcoal to fuel the generator.

I was cutting the pipe for to outlet of the filter when the generator quit. I fired it back up on gasoline to finish the last couple cuts and to make sure the generator was still going to run and to flush out anything I might have put in it using charcoal gas.

I expect there to be leaks in the filter because the generator running on charcoal doesn’t run the welder as good as it does when running on gasoline but this will need some form of gasket to seal the two pieces back together so shouldn’t be a problem.

I didn’t time this run but I run it pretty long and was pushing it pretty hard most of the time running the welder and my gasoline gage still shows full.

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It is amazing how just wood tar down in a sealing slot area mixed with stove rope or welding blanket fiberglass will seal things up. It get hard and seals. It is very mess though. If we can get a way from all the high heat silicone products in making gasifiers it would be a great savings. Show use more on how you do this Giorgio we need to know your secrets.

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bob, nice the picture of your inventor workshop…on another topic…
with my sealing of lids , there is no secret…as i use only coal, there is no tar what can glue the rope gasket in the metal seal surface…i make relative large sealing surfaces so from 5 mm to 12 mm to avoid consume of the stove rop by sharp small metal sealing surfaces…than , when i use a 12 mm rope, i make the gutter, where it lays in , smaller, in way it keeps from alone without glueing by silicone or others…on the iron glue surfaces some rust can make, that the stove rope glues on, therefore always a bit of grease on the metal surface is good…with stainless of course this problem not exists…
but i give also on all sealing ropes a bit fat on, first for avoid that all the fine fibers go away in air, second because the rope is made from a number of strings, and there are of course hollow spaces…with a bit of fat they got closed, and even more if some fine ash settles with a while on the fat on the gasket, when cleaning and so on…
i use not the round shaped rope . but the square shaped…
the adhesive stripes on the cut ends are keeping well til now, but i think if it is not the case on some build from someone, i can immagine the cut surface could be also glued together with a bit of this silicone, in way that the ends not can open…silicone on the cuts, and than putting the rope in his gutter - strong seat - cutted end strong together, should also work , i think, when the silicone remains elastic, there i have no experience…
only is to take in consideration that the seal rope shrinks with a while by pressure of the lock screw…this is to observe for the lock mechanism construction.

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I do pretty much the same Giorgio with tongue and groove and the rope seal in the groove usually on the hatch side. Only a few dabs of silicone to hold the rope in place and seal the ends.

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For those wondering how my simple pipe nozzle was lasting so long…

This is what I found when I opened it up today.

I don’t have time today to mess with it but I’m going to have to put a different nozzle in before I run it again. Haven’t decided exactly what it will be yet. I have a needle valve and an air mattress pump ordered to add a water drip and make lighting it easier.

The new access door will make changing the nozzle possible for experimenting so I might try a flute nozzle or a vertical pipe cap with holes drilled in it.

I have that carbide piece but even a 1 inch coupler isn’t big enough to mount it and I don’t want to use it yet.

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Try a piece of 1 1/4" pipe. Clean out the weld seam with a file and you should be able to press it in with an arbor press.

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