Dave and Kyle, I use sealed steel drums for storing ground charcoal, and noticed condensation dripping from the lid when I opened it up. I let it sit for a couple days with the lid off, and then replaced it. Next time I looked, there was no more condensation. Same with other barrels. My theory is that any sort of moisture in the charcoal rises to the top, (just like humid air rises and forms clouds) and condenses on the bottom of the lid. Just watch the humidity, and when a dry spell (like 12% R.H.) open the lids to let any moisture out. Moist air is lighter than the surrounding dry air. After a while, there wonât be any moisture left in the barrelsâŚMy 2 cents worthâŚ
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Abner itâd be interesting to see how your one long slit burner would act as a âRubenâs Tubeâ if one put a speaker on the end of it.
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Thatâs really cool.
But I kind of feel like these guys have too much time on their hands. They need some kids, and chickens, and sheep, etc. etc.
But I do have a set of old MagneplanarâsâŚnaw.
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I have used a cheap cordless leaf blower in the past with a speed controller and a dust sock over the blower tube to catch the bulk of the dust and any fines that are light enough to be sucked into the air inlet as I am crunching the charcoal up , and depending on how strong a suction it has then mount it at a safe distance away so it wont suck up small pieces of charcoal only the dust .
Ray , every 2 cents shared makes up richer and the way my brain cells are being spent everyday boy I need as much as I can get hold of 
On the video that abnervalbuena posted showing the slit pipe flaming gas out of it , was that natural gas or wood gas that was alight ?
Dave
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Multi-turn gate valves are much better than ball valves for fine control, but Andyâs valve is a beauty. Iâm going to give it a try.
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Ok guys, have a nice day. One answer for both questions. The gas on the video is butane/propane mix and, aldo it´s around 8 - 15 psi presured it´s high compared to wood gas. Presure on the kiln is directly proportional to the temperature and the amount of possible generated gas. By this saying it´s a VERY LOW PRESURE SYSTEM, some where I read it was something like not over 3 psi. The advantage of the slot is it´s low resistance almost all the way, we where thinking that in the giant kiln, we will start thinner and end wider at the extreme of each 1" pipe (it wil have 3 1" pipes of about 140 cms each ( 3,5 ft?). I believe we could be burning in about 3 weeks and we´ll also make a video to veiw all the process. The other thing is that it has no secundary air inlet, it relies only on temperature to burn the outcoming woodgas and crack it. Abner
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Another retort option to consider is an internal combustion chamber/flue. Here are the guts of our crop-waste retort in Rwanda. The internal SS pipe was picked up as free scrap leftover from a chimney relining job in the US. Gas entry holes are drilled along the lower sides of this pipe. An expanded metal grate is slid into the tube. A finned adaptor is added at the air inlet to create turbulence for a hotter burn.The lid has an internal layer of insulation. A metal box is built around the bottom barrel and is filled with wood ash as insulation. The upper barrel serves as secondary combustion chamber and heat source.
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Hi Bruce
The upper barrel is it crossed by the SS stainless steel pipe?
I presume that the upper barrel is used as an oven
Thierry ,Qc
SS pipe does not pass thru the upper barrel. SS in and stove pipe out.
In our case the upper barrel has three holes on top to receive three 5 gallon buckets for solid waste pasteurization. It of course could be used as an oven.
I use a similar setup in my backyard using a sealed 1/2 barrel for the upper chamber as a heat source for drying retort feedstock.
There is a moisture vent fitted with a ball valve near the top of the bottom retort that is left open during startup until burnable gas emerges. The valve is then closed forcing the pyrolysis gas to find a new path thru the holes in the internal flue which creates a self-sustained roaring internal fire until biomass is fully pyrolyzed.
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I have built a furnace almost identical to yours.
I did not managed to completely carbonize all wood (some large pieces of wood has not completely charred heart)
A lot of smoke when the wood into the furnace starts gasification
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Good insulation is critical. Mine has 3 inches of rockwool all around. Enlarged finned air inlet for turbulence creates higher internal temp. and less smoke. Exhaust temp. of bottom barrel is 1100f.
Hi Kyle and all, Here is a short video of my processing plant for making engine grade charcoal. Just another way of doing it.
Gary in PA
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Some Minor Changes
Raining here much of the day.
Took the opportunity to make a few minor changes to the gasifier.
Added a 1 1/4 inch through-coupling at the base, and plugged the 1 inch coupling.
This allowed me to get the end of the alumina nozzle into a more correct position by moving the reducing coupling from inside the reactor to outside the reactor.
This will also give me more versatility to test different nozzle designs, etc. I might use the extra port for a thermocouple or something in the future.
Also came up with a ratcheting coupling for the drill starter. This is just one of those cheap ratcheting screw-drivers. I removed the handle and filed down the sides to fit inside a deep well socket. It is cheaply built, so not sure how long it will hold up.
This time, we also have enough fuel grade charcoal to completely fill the reactor.
Ready for another test!
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Run 5 Report
Did another run this afternoon.
Here is the good news:
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The nozzle still appears to be in good shape (havenât pulled it yet, but it looks good through the lighting port).
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We increased the load substantially. Put a 5 HP air compressor on it, along with the 1000 watt boom lights. I estimate we were pulling 2800 watts (more than that peak). I really didnât expect it to handle the nasty start-up surge of the compressor, but it handled it no problem.
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The ratchet for the drill starter worked fine. This made starting up easier.
The not-so good:
At the 45 minute mark, the gasifier started heating up again at the top. We had to shut it down at the 52 minute mark. We are really hoping to get to a sustained run time in the range of 2 hours. We are a long way from that goal. I suspect that the average size of our charcoal might be a little big. I am going to try and tighten up on the large screen. But, so far, I have not been able to find any 3/4 inch hardware cloth. What are you guys using?
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I use the diamond mesh they make trailer ramps out of; about 3/4". I mounted it in a frame and bash my charcoal through it with a flat shovel
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Why do you need 3/4 inch screen? Doesnât your grinder grind a lot smaller than that anyway? I use just one 1/4 inch screen tilted at a 45 degree angle. The largest pieces that make it through the grinder are 1/2 to 5/8 inch and just dust and about 1/8 inch flakes make it through the screen and the rest goes in the finished tub.
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I have found that it increases my yield by a noticeable amount if I take the charcoal from the retort and âpre-screenâ it before feeding it to the crusher. A good bit of it is already small enough. This is also a good opportunity to check for any torrefied wood (and to pick out choice nuggets for the trusty old Weber).
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Hi Kyle , could you remind me of the size of the gasifier how many inches high and what diameter and how far off the bottom is your nozzle ? and what is the hp and KW of your generator .
Cheers
Dave
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Dave - I am using a grease barrel. I believe it is 16 gallons. It is around 12-13 inches in diameter. The overall height is around 30 inches. The nozzle is 3 inches off the bottom (center of nozzle).
I mispoke earlier when I said it was full this time. It was actually around 3/4 full (prob. around 23 inches of charcoal).
The generator is rated at 5500 watts continuous.
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Hard wood or soft wood?