Tom Collins' Gasifier

What people present to us in Imperial is much clearer. But, I still have to deal with metrics when trying to work through the calculation in FAO72
The lid? I thought so, but on shut downs it still leaks smoke. I have so much pressure on the leaf spring that it sometimes takes both hands to get it latched. I have had many “burps” and it relieves the pressure as it should.
The reduction bell is gone. My analysis of the problem came down to to much velocity in the reduction bell. It was eating up the char, allowing the char from above the restriction ring to fall through and be oxidized into ash also. Thus allowing the wood to fall into the restriction ring and plug it. There is very little discussion on the design of the reduction zone, I have gone with a more conventional inverted cone reduction bell. This would allow the velocity to slow down and still maintain an insulated wall on the reduction zone. That is pictured in the first picture in the last group. Despite having it all together and ready for a trial, I could not get out of my mind how easy it would be to try a partial WK design. So that is what I have done. No running today so everything is the same TomC

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Hi,Tom!
17.8.2019

A leaking lid is ALWAYS upsetting the oxidation process and preparation of CLEAN char. For successful reduction!

NOBODY can control an oxidation process with nozzles, if random amounts of air leaks into the silo.
ALL OVER smoldering does not reach right temperatures.

You cannot regulate the char PRODUCTION by changing the gas velocity in the reduction zone!

Char consumption by reduction OR oxidation, depends on how you handle the available in-coming air.
LID OR NOZZLES!

A lid puffing after bunkering is OK, but further puffs indicate LEAK!

If the lid cannot be made tight, there is one solution available: But it needs an extra “component” added!

Max

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From everything I’ve seen and read, human kind just doesn’t have a good understanding of the natural laws that govern gasification or solid fuel combustion. This has left the way clear for Wayne to come up with a gasifier that serves his needs better than anything he could buy. And similarly it has allowed Ianto Evans, Pieter v. d. Berg, and Kirk Mobert to build on eachothers’ work and make wood burning stoves that are more efficient than anything seen before. The ‘rules’ were holding us back.
Rindert

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Hi Rindert!
17.8.2019

Gasification and complete burning processes have common parts and diverse parts.
They cannot be set on the same line!

Max

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I tested my lid seal by plugging off the air in take to the gasifier and letting the engine pull on the gasifier. I was getting the same vacuum reading in both the cooling rail and the hopper With a leak in the lid I thought I might get less vacuum in the hopper. Now facing you I question if that was a logical assumption.

Correct.

Don’t understand

If you increase the gas velocity and O2 contained in the gas, you will convert the char to ash more quickly. ( blowing on lazy char will bring it back to life.)

I have two rings in the lid to contain the fireplace rope, and one ring on the hopper that can press into the rope . What component does it need?? I can not begin to remember all of the seals that I have tried over the years and I am still where I am. TomC

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Hi,Tom!
17.8.2019

If you did that with the gasifier hot, a tight lid would have stopped the motor straight away.

But doing it on gasoline, also stop, if no other air feed available.

The gas passage from the silo, through the hearth tube and further tubes is so wide, that a modest leak by the lid would not give any noticeable pressure difference.
Still too much leakage can spoil proper charing!


Instead, do the test with the blower in sucking mode, and detect how much is coming out from the blower; that is telling how much the lid leaks!
Of course provided, that the nozzle-air is still cut-off!


Allover smoldering = weak burning outside nozzle-blasts, making distillation gases, which avoid proper “treatment”.


Again: I did not say Flow!
I said: Velocity!
And that by changing the flow-area in the reduction chamber. Same flow.
You have recently decreased it (the velocity) by the cone chamber! BAD. Returning to ash blocking!


The extra component is the good old cone-ring just above the nozzle-tips, forcing the leakage-air into the nozzle blasts, thus being included into the intended circulation. (635 / May 2017)

Max

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Oh Max, Oh Max. You don’t know how much work your comments can cause me. But I usually try to comply. The following one seems simple to try, but I think that is a little theoretical.

I have to do this test every time I remove my air cleaner off the throttle body. I start the engine and place my hand over the air horn on the air cleaner and the engine usually and should stop rather quickly. However in reality, with 25 ft. of 3" pipe leading up to the engine and a 30/40 gal can with hay in it, then 40 ft of 4" cooling pipe and a 50 gal hopper/gasifier and a couple of condensation tanks along the way, I don’t think anyones system would shut the engine down I would challenge you, the next time you take your car for a ride, to try it and report back. Starting at your air preheater-- I really suspect that box at the air opening to the actual gasifier with the exhaust pipe leading into it, would pass the mustard.
Having said that, I admit that every since I have run this truck on wood, no matter the gasifier design, that I have had air leaks— I have NEVER run this truck with the secondary air feeding the mixer box, OPEN. Always full shut. So, my next project will be to try and figure out where my leaks in the system. I have done this drill on several occasions with no conclusive results. I sincerely believe that no matter the design of the gasifier I use, it would definitely run better if I had control of the air. TomC

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One of your best balanced comments ever TomC.
Mighty proud of you, sir.
You got grit, and stick-to-intuitiveness to get where you are!
Steve unruh

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Hi, Tom!
18.8.2019
How about your Kirby blower?
Does it have a shorter tubing to your gasifier, to eliminate the majority of suspect joints?

If the Kirby sucks straight from the gasifier, many leaks could be avoided?


The igniting box on my Audi gasifier brings pressurized air, only for start-ups.
The bending metal hose comes from 2 series coupled ventilators bringing the startup positive blowing.
I have no sucking functions at all. But the motor. And no gasoline equipment.
Loosing the bending metal hose coming from the ventilators and covering the curved stud (with back-flap) with my hand the motor stops promptly.


A straight line from the gasifier to the Kirby would temporarily eliminate all fatalities in the rest of the setup. This way you can genuinely test how much your lid leaks. Just for a cold sucking test.

I am sorry for the trouble I am causing, but I just want to investigate the functionality once and for all, for your benefit…

Max

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Hi Tom, I had the same, lid leaking at shut down, because at shut down it has positive pressure pushing smoke out the lid. No leak with a vacuum on the lid drawing lid down. I redesigned lid seal no more leaks.

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I wanted to take another test run in my truck; but got detained. I had purchased a nice shiny piece of aluminum to put a skirt around the bottom of the gasifier. To kind of dress it up like an European, that I won’t mention his name, but his initials are JO. Problem was I used aluminum and he used stainless steel. On shut down, flames backed out of air intake port and started melting my pretty skirt.:angry: so today I had to make a “flipper valve” to stop the flames


Seeings that took most of my day, I decided to do another project that has been hanging over me.
Yep. I put in one of those converter things that changes 12v to 120 v. Maybe now I won’t need a plug in or a generator to run my Kirby vacuum.:smile: Just worry about the battery in the truck. TomC

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Yes Tom , I agree with you if you have the slightest leaks when idling. But if I bring The RPM up the engine should die. The hardest thing I have dealt with is air leaks some where in my gasifier system, and using the auto mixer. The slightest air leak in the wood gas lines cause a lean mixer when using the auto mixer. It has been a on going thing with my gasifier system. But what I have learned perseverance will win out. Just keep looking for the leaks, especially the leaks that let air in and no smoke out. They are the hardest ones to find, but when you do find one you will get a SWELYF. Smile With Every Leak You Find.
Bob

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Tom, your truck looks dressed up for inspection now.
Btw, my skirt is aluminium too.

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That is very unfortunate. However on the bright side, you are halfway to your first post in “All about metal casting”

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Can we see a ‘close up’ of your flipper valve, as you call it. Might be a good safety feature on some rigs.
Rindert

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Rindert; The overall picture is back a couple of post. Here are a couple of close ups. No big deal


I would have liked to taken a video of it working, but Max has me on a project of taking all my plumbing apart to check for leaks. TomC

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Hi, Tom!
21.8.2019
I have only indirectly put your gas transport system under question; you are yourself drawing the conclusions! (I have never before heard anything like it)
But well so! Your description of the condition is not very impressive.

A proper work from the beginning would feel good today.
I wish you proper results and air regulation enjoyment to come!
That will help to perform the lid-test without extra temporary arrangements.

If you return to the swift-flow reduction and a proper nozzle cone ring, I hope you get enjoyable performance.

Your back-flap restricts itself; it has the shaft on the wrong side of the flap-plate!
And it seems not to be tight when closed!

Max

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When you find the leaks just SWELYF. I found a hand full of small leaks that were giving me trouble. The small leaks add up to a lot of air getting into the wood gas stream that is not wanted. Making weak gas, and poor performance of the gasifier.
Bob

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Well performance wise small leaks where the gas is cold dont matter at all. We blend air in anyway later on. Hot parts are critical, Jakob learned that the hard way driving to Argos. Cold leaks make different problems usualy when the gasifier is cooling down, air entering the gasifier will mess up the charbed, specialy in a lmbert! Now that one l learned the hard way :smile:

I agree with Max and l think we put to litle effort to make the system air tight. I stoped useing screw on joints, flanges with seals etc a while ago. All my joints are either threaded pipes, welded or a sewer pipe with a self tightening seal. And still sometimes eccidents happen, like a broaken weld in my previous gasifier. From that l learned the only proof way with using dome shapes (JO always does, he is smart from the begining :smile:)

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Good morning Max; It’s 2:00 am and wood gas is spinning in my head.
You asked if my Kirby was directly attached to my system. The answer is ‘‘no’’. I have a rather complex plumbing system— so I can both create a vacuum and pressure on the system.
Every thing you question in my system I accept as things that would make the system better. In trying to follow these suggestive questions, there have been misinterpretations, and because I am not working from a ‘‘machine shop’’ things were not done to either of our liking. The condition of my air system is pathetic, but it has been sufficient to allow to allow me to ‘‘drive on wood’’. The condition of your system, I considered ‘‘utopian’’ and did not try to obtain it. Now knowing that it can be reached, I am trying to improve my system.

Today I started with my air cleaner on top of the TB which acts as part of my mixing system. I found a couple of pin holes rusted threw. Repaired them. I think a bigger problem is the rubber gasket on the air cleaner between that and the TB. With age and heat it is very stiff. Don’t know if a new one is available for this old beast.

A big problem showed up in my secondary air valve. It is the choke butter fly off from the top of a carburetor from a four cylinder engine. Never suspected it wasn’t doing the job. It did very little to stall the engine when I closed off the wg line to the mixer and then closed the choke butter fly. Took the choke body off and siliconed the mating surfaces. Another trial and it did a better job of restricting the air but made a whistle indicating, still leaking. Tomorrow is another day.

I had to cut up the ‘‘restricted flow’’ reduction bell for material. I do have the inverted cone bell and screw in nozzles that can be installed rather quickly.

I asked but you didn’t reply; if I have some hot lackluster char coals, and I blow on them, they will ‘‘come back’’ to life. Is that because l am feeding more oxygen to it — the velocity of the air is causing the O2; CO/CO2 molecules more excitement — or is the velocity just knocking the ash off the surface?? With the ‘‘restricted flow’’ reduction, the char burned away without pyrolitizing the wood which fell into the restriction raw.
See if I can get to sleep now. TomC

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