First run TLUD

[Merlin]

I have 5%primary and secondary air inlets. I do have a bit of smoke makes me wonder if the intake air needs fine tuning. I am burning ERC pet bedding and the beastie is done in about 10 or 12 minutes. it gets incredibly hot towards the end you can see reflection of flame on ground and the side of the can are glowing red. Hard to tell exactly when it is done. I see the wood has burned to the bottom but I wait for the flame out the chimney to die back then stop it. If this works it is much cheaper and much easier and 50 times faster than the retort. Sorta like miraculous. If I can do it anyone can and make charcoal for every use.

If anything looks wrong please let me know. Having so much fun tempting to finish the whole bag of ERC tonight! Included are a couple photos so you can see what I'm saying. Don't know why not oriented correctly.

[OldMarine]

It looks as if you are getting too much air in the bottom. I run a ring of masking tape down the side and around the base so I can see the progression. I've never had my TLUD glow or jet flame like that.

We need Boophoenix to chime in here.

[chuckufarley]

Mine will jet flames like that and glow red if I get too much airflow from the bottom holes.

 

One thing I played with was compacting the chips in the bucket. Are you just dumping them in there and lighting it? If so, next time try filling it about 1/3 full, pushing down on the chips to compact them. Repete this untill it's full. The compaction of the chips played a huge role in the burn rate on mine. Loosely filled, it roared like a jet engine and burned out in less than 10 min. Medium compaction, burned nice and smooth, much cooler and took twice as long.

 

+1 on the masking tape down the side. It really helps show where the burn is untill you get used to it.

[Boophoenix]

Merlin, how did you end results turn out? Did you ash any of the chips?

 

I've watched and studied on these a fair amount and my first inclination is with Patrick you look to be running a little hot with excessive inlet air flow from the bottom. My second inclination is even if your cook went well you may have over charged the bedding a little. That cherry red at the bottom near the end of the cycle with flames and sparks rolling out the top make me wonder. I'll almost guess you have ash in the load?

 

A picture of the bottom of your bucket would be of intrest if ya don't mind.

 

I'm no expert by any means so take what I've said with a grain of salt.

 

Chuck, interestingly simple approach. You chimed in while I was typing.

Edited September 16, 2016 by Boophoenix

[Merlin]

Thanks for observations! No I did not compact the chips and it was over quickly. I can't see any ash. The bucket still had a little glow when the flame out the top died back. I immediately sealed it at that point. Don't know about the ash as it is not visible. Attached are photos of bottom and secondary holes. They are 1/2 inch. I could put in a few bolts to reduce. Sorry for inverted pics - maybe cause I am using cell phone.

Edited September 16, 2016 by Merlin

[Boophoenix]

Merlin, I'm inclined to think you way over sized your bottom holes. Test your charcoal though if it performs to your expectations run with it. If you didn't see ashing on the tips you might be fine. Keep us posted on how it performs if you wouldn't mind.

 

I like a slow gentle cook trying to preserve the volatilities. It's such a simple process that ya just have to check and watch at the end I wouldn't mind how long mine cooks. It won't be long and the weather will start shifting to were it's a pleasure to sit around a warm TLUD and relax. A second reducer on the stack should help slow things down a little too.

 

It's hard to tell from the pictures, but it almost looks like your drilled the holes? If this is the case be very careful of metal shavings contaminating you charcoal if you plan to mill BP. The general acceptable safe practice is to punch smaller holes.

 

The last can I made I used a thin bladed flat head screw driver for a punch. Invert the can bottom onto a board and punch away.

 

Merlin, don't think I'm being critical of your sharing please. I'm adding additional thoughts and experiances for the next guy that might read the thread as well. The buck never stops with the few in the thread others read them too. Who knows the next guy might be the guy that solves a lot of curiousities those of us fascinated by charcoal have.

Edited September 16, 2016 by Boophoenix

[Merlin]

 

Merlin, I'm inclined to think you way over sized your bottom holes. Test your charcoal though if it performs to your expectations run with it. If you didn't see ashing on the tips you might be fine. Keep us posted on how it performs if you wouldn't mind.

 

I like a slow gentle cook trying to preserve the volatilities. It's such a simple process that ya just have to check and watch at the end I wouldn't mind how long mine cooks. It won't be long and the weather will start shifting to were it's a pleasure to sit around a warm TLUD and relax. A second reducer on the stack should help slow things down a little too.

 

It's hard to tell from the pictures, but it almost looks like your drilled the holes? If this is the case be very careful of metal shavings contaminating you charcoal if you plan to mill BP. The general acceptable safe practice is to punch smaller holes.

 

The last can I made I used a thin bladed flat head screw driver for a punch. Invert the can bottom onto a board and punch away.

 

Merlin, don't think I'm being critical of your sharing please. I'm adding additional thoughts and experiances for the next guy that might read the thread as well. The buck never stops with the few in the thread others read them too. Who knows the next guy might be the guy that solves a lot of curiousities those of us fascinated by charcoal have.[/quote

 

Not at all. I have learned a LOT on APC.

You are right about drilling but on the TLUD instructions I used it said drill. Also a very good point about metal shavings. This could be a cause for some ball mill explosions. I will try to close up 10% of holes on bottom and see what effect it has. Otherwise get a new bucket and start over. But I believe the TLUD is THE way to make charcoal. Thanks much for your help!

[Merlin]

I have 23 1/2 inch holes in bottom being too much. How about 35 to 40 1/4 inch holes in a new can?

[Boophoenix]

If you have access to alum tape for ductwork. You may could even use aluminum foil if you're careful to make a false bottom to test ideas with. You might need to prematurely stop the burn though.

 

What I noticed when I first started with cooking and had some time to tinker my flame front heat was about an inch tall in a gallon bucket. This inch ran about the same temp as the reducer bells in my stack. If memory serves correctly that was around 800 degrees. Which might still be a wee bit hot. Just below that flame front the temps were high 100's to 200's. A couple of inches away ambient outside temps.

 

I'm still the noob here and fairly new to pyro as well. Some here will know of me and my ponderings and ideas from other venues, but I'm by no means an expert just a curious party that is fascinated With charcoal.

[chuckufarley]

One technique I've heard of that sounds interesting is to make a plate with your holes punched in it, stand it off the bottom of a full (undrilled) bucket about an inch above the bottom. Plumb in some pipe and a ball valve,(under the punched plate) and you can then adjust the amount of intake air by opening or closing the ball valve. Just make sure you keep the ball valve far enough away from the bucket to avoid heat damaging the seals.

[Boophoenix]

Merlin, I might would go even smaller in diameter. It's easy to open a hole up if it's a little small. The most likely cause you'll have from not enough flow is burn out so you'll not loose material. There isn't any rule that says you have to cook a full bucket either while testing. Start with half a bucket if ya have trouble keeping it lit open up the holes a wee bit ( ya like that technical term ).

 

After ya tune that a little you may have one more tuning to handle a full load, but it'll be easy as you've learned along the way how little ya need to change to get a good flow.

 

If ya try smaller holes and need to open them up try alternating the ones ya open up just a hair. This will give ya a little wiggle room I'd bet. If ya need a second tuning open some additional holes alternating the patern again. Think of it like adding moisture to BP it's all looking good then spritz it's a pile of ooze, lol.

[Boophoenix]

Chuck, that's an awesome design. Lloyd's is that way. I'd be inclined to say it's the best design because different materials and batches will cook a little differently. This gives you endless opportunity to tune for the material.

 

I've got plans for a 35 quart stainless stock pot I am gonna do that way. It'll be all stainless with the hopes if I can get around to get a little machining done it'll all tear down and store back into its self. I can't settle on how I wanna plumb the inlet in. I keep trying to find a stainless flush mount butterfly valve. With the addition of some small feet for circulation under and to protect the valve during storage it should all store nice a tidy when done is the plan.

[chuckufarley]

Boo,

 

Lloyd told me about that design after I built mine. Thought I'd pass it on again, it does seem ideal.

 

I like the idea of being able to break every thing down and store the parts in the tub in your design. With a double bottom design would the valve have to be centered in the bottom? Couldn't it be placed on the side as well? I think as long as you have enough airspace between the two layers the air should disperse evenly without just burning up one side. Then you could set it flat on the ground for the burn and just unscrew the valve for transport.

 

I can get all the buckets I want for free from work, I might have to experiment on that a little.

[starxplor]

Thanks for observations! No I did not compact the chips and it was over quickly. I can't see any ash. The bucket still had a little glow when the flame out the top died back. I immediately sealed it at that point. Don't know about the ash as it is not visible. Attached are photos of bottom and secondary holes. They are 1/2 inch. I could put in a few bolts to reduce. Sorry for inverted pics - maybe cause I am using cell phone.

 

I also use the paint can and ceder pet bedding. I highly second the compressing recommendation. Just remember, you only need to compress, not compact. A good rule is press down and watch it come back up. If it comes back up to where it started, leave it there. If it comes up but is lower than it started, give it another press. This way, it still has some room to breath but you get as much in the can as is economical.

 

Mine does the same thing, it literally sounds like a jet engine for about 30 seconds near the middle of the burn then dies back down. If it sounds like this for most of the burn, it could be a matter of mismatched amount of air intake between the bottom and the top causing air to speed through.

 

As for the glow when it is done, yes, this is the bottom charcoal trying to burn to ash. You should seal it as soon as there are no more flames, look for flickering light as the fire gets to the bottom, then when it dies to a solid light without flickering seal it up.

 

One last thing: I highly suggest adding a 4th brick at the bottom. I have tried using just three and the right little breeze of wind can tip it over (lost two batches before moving to 4 bricks).

[Boophoenix]

Chuck, it could very well go into the side. If the height of the diffuser plate will acomodate a nipple for a pipe that's not a bad idea. I haven't explored that avenue very far. My pot has a built in lip that will be ideal for a diffuser plate. I'm trying to stay within that constraint. With the addition of a few stand offs to keep the center lifted the outer lip will hold a diffuser plate quite well.

 

I think on edit I can find buttons to try to add a basic photo of my plan. Brb

 

I think I got it added. This is just a mock up of the parts stacked and the addition of a ghost mine mortar tube to simulate the stack is with there is a square base in the stack. I haven't cut my stack pipe yet and balancing a 6' schedule 40 SS pipe in there in the gravel could have been dangerous for my truck sitting there.

 

Edited September 16, 2016 by Boophoenix

[Boophoenix]

Good tips on the compressing. I've never considered that as I want to tune with loose chips to have the option for solid material ( splits and sticks ) as well.

[starxplor]

Good tips on the compressing. I've never considered that as I want to tune with loose chips to have the option for solid material ( splits and sticks ) as well.

 

Even if you use solid material like splits and sticks, there should still be some space between them. If you pack the can so tight with splits that none of them move if you shake the can side to side, take a few out or re-arrange them. There needs to be a way for the air coming in the bottom to reach the fire layer in sufficient quantity and dispersion that the fire layer moves down at a consistent rate through the whole can, otherwise you can end up with a 'corner' of wood or ash left at the end.

[Merlin]

Lot of info here. I am going to " punch" holes in a new bucket tomorrow erring on too few then testing and adjusting. The idea of a double bottom with an adjustable valve would be supreme. I am just going to get a basic one going for now maybe toy with a more advanced one later.

Now about the important stuff. Punch not drill. I would have bet there were no metal fragments in my charcoal but I ran a potent magnet through it and there were two small fragments. A potential ball mill explosion! I am going to make a new one tomorrow.

Boophoenix you may have saved me. My wife thanks you as well. Maybe noobies reading this can learn the smallest thing can lead to seemingly inexplicable tragedy. This was a good post!

[Boophoenix]

Star, if dialed in correctly it should be able to cook about anything. The material heating and releasing combustibles are the fuel. The fuel would dictate the heat. Which in turn dictates the draw. I've cooked loose twigs in a gallon can with no problem that I noticed. It was an example cook for another idea unrelated to pyro so I didn't investigate really closely.

 

Since wood draws up once the moisture has been heated out of it the air flow will increase as this happens. My prefrence is to tune to a mild burn for this reason. However if packing chips overcomes excess air I'm not one to discount the option for others who plan to cook chips. As stated above I'm still learning and new to the art. I rely on experiance, shared information, and plenty of speculations. I'd like to think anyone taking advise from anyone else thinks about it a little in their own and forms there own ideas from there. I know I'm often wrong in some of my speculations and ideas, but enjoy the conversations about those wrongs and learn a lot from them.

 

 

Merlin, I'm glad ya thought to check. No need for any thanking it's why we are all here to share info and ideas to promote the art and safety doing so. It's not a bad practice to do anytime you source material from anywhere you didn't cut yourself. I thought I could see some burs in the holes you drilled that form when the bit passes threw the material and tries to hang a little. Even if you cleaned all the shavings from drilling out you might would miss a bur and a cooking cycle might drop that one. How dangerous would that one be who knows for sure, but why take the risk is how I like to think about it.

 

If you get a chance compare the cooked batch you have now with one later. I suspect you'll be slightly surprised if you look closely at the variables. The current one should have a higher ignition temp over a cooler cooked charcoal not to mention the preformance difference you should see. I'd enjoy hearing results if you care to dabble with that concept.

[Merlin]

Sure. but from personal experience I prefer to mill powder in cooler less humid weather as I think it Mills better.Its still 95 here. I find most of the time it's better to listen to people who know the facts and are experienced than to discover for oneself. That is why I value what Mumbles, Lloyd, Caleb, and Braden dynomike and others say.. I suspect you understand the biochar process. I am going to get a cooler burn set up. BTW TLUD is vital in third world countries as a source of biochar and cooking and heating. It may be useful here before too long. I suspect you know that also.

Again thanks for your help!

[mikeee]

One easy solution is to make an adjustable air shutter on the bottom of the TLUD cooker.

Some people have used a ball valve attached to a long nipple attached to the bottom of the cooker.

This method requires a false bottom in the cooker with the holes punched in the false bottom.

The ball valve can be opened or slowly closed off to find the best amount of air for your cooker.

Another method is a metal slide shutter that can be opened or closed to adjust the air intake.

Look at a Weber Grill they have air intake shutters on the top and bottom of their grill for the same reason.

The Weber air shutter is a simple design and could easily be mounted on the bottom of a TLUD cooker.

The hard part would be making adjustments while it is cooking.

A slide shutter could be mounted on the side of the cooker towards the bottom, you would still need a false bottom,

but you would be able to slide the shutter open or closed while it is cooking.

The Weber style air shutter could be adjusted while cooking if you have the TLUD cooker elevated off the ground allowing

you to reach under and adjust the shutter open or closed.

[Merlin]

Update. Made another bottom same number of holes but 1/4 inch. 1st run was slow and cool but did get a lot of ash. opened holes (a wee bit) and burn seemed about right. used masking tape down side. No glowing bucket and no flames or sparks out the chimney. I have burned a whole bag of ERC but there is always some ash. Even if you have a perfect seal the remaining air will allow some smoldering and ash to develop. I would expect that some amount of ash is unavoidable?

The great thing is no more trips to the dollar store for propane.

[OldMarine]

You will always get a tiny bit of ash because some of the wood is burned to convert the rest to charcoal. Usually mine just has some gray ash around the edges of the uppermost chips but performs wonderfully. Even when I used a retort I got some ash on the tips of my splints due to them burning in the air contained inside the wood itself.

[chuckufarley]

Sounds like your making good progress Merlin. Are you using the same bucket you cook in (holes in the bottom) to seal off the charcoal from oxygen? If so you might want to try get to getting a second bucket (no holes and agood lid with a seal) to quickly dump the charcoal into when your burn is complete. Not sure if it will help reduce the ash content, it was much easier for me to do then deal the bottom in sand...etc. You also have the advantage of being able to immediately run a second(or third, or fourth) batch.

 

Just my $.02

[Merlin]

Your 2 cents is good. Thanks what I was doing until I had to punch holes in the second to correct for too large holes in the first. For some reason I can't find 5 gallon metal buckets at Lies or Home depot so I order them online. I will have to get another one. Be glad when weather cools so I can start milling BP.