Tom Collins' Gasifier

Hi, Tom!
22.6.2019
Here is no contradiction! It affects all places on the northern hemisphere,
locally “for itself”: The highest solar angle to the horizont, for the year.
Above the northern polar circle there is no total sunset for some days…

Happy midsummer!

Max

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And at the north pole today the sun goes around in a perfectly level circle at the highest elevation. Which won’t be very high. 6 month of light, and 6 months of no sun at the poles. Even at this latitude the sun sets far to the north, and this time of year it looks dusk due north at midnight. At 57°N you see blue sky looking north this time of year. 66° is the arctic circle, the sun doesn’t set today.

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Hello guys; I had problems with the charcoal I put in to the height of the nozzles burned to ash before any wood got pyrolisized above the nozzles. Twice I had good short runs but the non-chard wood got stuck in the restriction. Looking at the design, I decided the reduction zone looked to small. I decided that an old fashion inverted cone from the restriction to the grate was needed100_3043
The first picture is the new reduction zone
I had it all set to try but I couldn’t help thinking back when I removed the nozzles, restriction ring, and reduction bell with the grate, how much it looked like a WK type gasifier. It has 10- 5/8 in holes in the fire tube at just about the right height. it has two pins at the bottom that could hold a restriction ring. Then maybe trying what Kristijan and JO are advocating; go without a grate. I do have a clean out door to empty the ash if needed.100_3040

Dropped a ring that I had cut off my old reduction zone down on the pins at the bottom of the fire tube.100_3044

That really made it look like a WK. Hmmm! To give the wood angle going towards the fire tube, I copied the WK fingers. Now that really made it look like a WK
100_3046
If looks mean anything, this looks a lot like somekind of WK copy. But would that work??? I don’t have any of the air preheat stuff or drop box, etc. Just something that looks a little bit like the firetube.
Ok I got 7 gal of charcoal to fill the fire tube up to above the nozzles.
100_3050
I pocked a rabbit hole in the charcoal and took the torch to it. Then added 10 gal of really good oak that I had chunked.
100_3048
I worked the fire with my blower by sucking and blowing on it until I had a good grungy brown smoke coming out of the hopper. Got in the truck and started it on petrol. It was stumbling and carrying on so I shut of the injectors and fuel pump and everything smoothed right up. I put it in gear and headed for the road. When I pulled onto the road it was stuttering for a short time then it took off. It seemed to run very well. I have no speedometer so I don’t know how fast or far I went but at about 20 miles it started acting up. I pulled over to stoke it, but when I lifted the hopper lid, I was looking right at 10 nozzles holes with soft flames coming out of them. I dumped in 5 more gal. of wood and after a little hesitation, we took off for home. Lemons PLEASE.
I will run it a few more times and see what happens to my fire tube and then I will put my inverted cone reduction bell in and try that.
TomC

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Congrats Tom, I think once you burn a few loads it will settle in. Argos next year?

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Way to go Tom
Always exciting when a first run happens

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Congratulations Tom,
Now you need to start looking for places to go :smile:

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Oh Ya Tom, I can see the smile on your face. Good job and what everyone else has said. Keep the wood going into the hopper and let that char bed establish it self and you are set to keep DOW.
Bob

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JO Put the coffee pot on. If possible my first trip would be over to see you and Kristijan. TomC

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Thanks Bob. I didn’t follow many of the WK design, except the basics of the fire tube, so I plan on doing a hopper clean out and inspection after just a few miles. This rebuild of my Imbert was to be right to the suggested dimensions of an Imbert, so I had that fire tube made at a machine shop and I don’t want to ruin it by this crazy conversion to the WK design. TomC

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Hi, Tom!
15.8.2019

What are you up to?

Removing the nozzles is widely increasing the burning AREA aswell as making

the burning process floppy like a picknic fire! In the midst of an enlarged

burning volume.

That’s the reason for your “brands” reaching the restriction.

Increasing the reduction volume will bring back ashblocking and a miserable

reduction process.

All consrtuctive planning overboard!

Max

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Hi Tom,
What I can see looks good, imbertish wise. I think it’s important
to follow those dimension to the char collection area for the
full effectiveness of the imbert design. Can we see a pic of the lower
ash collection area. I believe an odd number of nozzles is called for in the
imbert charts. I did that and it works well. I guess the theory is that
you don’t have one nozzle’s flow interfering with the flow of a nozzle
directly opposite it.
Once you get a good char bed going reloading won’t be a catch up process
on refill. Looking good.
Pepe

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Hello Max;
What am I up to?? Impatiens,frustrations, and many other things. All I can do is apologize to you for the time you spent trying to mentor me through a rebuild of my gasifier. I will write you a note and try to explain, but for right now do not look at what is in my truck as having anything from an Imbert type gasifier. What is in my truck is a sloppy half-assed WK gasifier, that I have no idea how well it will work as a daily driver or for how long.
Again my apologies. TomC

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Thank you Pepe for the comments. I do agree with you on all accounts. Originally this build was to be by the Imbert suggested charts for dimensioning. No using tire rims or brake drums and accepting many dimensions these items gave. At the same time a member who I respect very much suggested 10 nozzles, so that is how that came to be. The jury is still out on how they worked; I had a problem and I gave up very quickly with out really determining the problem.
I don’t understand that char bed build up and better wood mileage with it. Thanks again. TomC

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Hi, Tom!
16.8.2019
What ever the construction,~ 60% of the gas consumption comes from the atmosphere and ~40% comes from the fuel, when everything is at optimum.

As before, the motor consumption rules the process volume modified by fuel-bit size.

Successful constructions show, that the “oxidation volume” varies
from 4% to 11% of the consumed gas volume per second
from “grashopper” size to 11-12 liter truck motors.

This about Imbert fundamentals…

These percentages are higher for the WK system.

As Pepe just pointed out, there are dimentioning rules for standard building.

The reduction part depends on how one is utelizing the gas velocity; just for ashblowing, or for turbulent mixing…

Max

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I don’t like rules! :unamused: Tom is going down the road. Whatever mojo he’s using it’s good. I think Tom’s crazy… like a fox! :fox_face:

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Hi, Rindert!
16.8.2019
Like or dislike; the rules are a way to describe passage areas in “cold&empty” fundamental drawing, and thus helping to get right velocities when adding fuel
and temperature expansion!

Added to that, chemical adding to the gas in the process…

They give a starting point, from which to “pronounce” personal aims in one direction or another direction.

Then somebody else can “trim” it in some other direction.

For “cold&empty” the picture is clear, flow by area = velocity, always comparable with other construtions.

Process volume to produced gas volume per second tells the intensity and quality…

Max

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The variables are so many when it comes to gasification. And yes the people of years ago have come up with theses math formulas and Demenonal sizes for gasifiers. Some of you have to stick to a curtain fuel size to make it work. Even in the more fixable WK Gasifier fuel size matters. The point is I enjoy try different things with my already proven design WK.
I think Tom likes to do this too, like many others on this site. And it is great having you Max and others looking over our shoulders as we work on the different gasifier projects. As I have said before there is hundreds of years of experience in gasification if you added it all up.
What I have learned on this site alone, should qualify me and others for a degree in gasification.
I just can not express in words gratitude from all the knowledge I have leaned from everyone on this DOW site. This knowledge is now going to people in third world countries to better thier lives. This DOW site is impacting the world and you all apart of it. Congratulations to you all.
Bob

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Again sorry Max. I do agree with you about rules. The object of this build WAS to follow those rules. But, somethings are not chiseled in stone and not having a good visible understanding of metrics, selecting some of the variables took a lot of time to NO suitable end. So I guess I jumped off the horse and tried to outrun it. TomC

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Hi, Tom!
17.8.2019
Sorry to hear that. Knowing that, presenting measures in Imperial measures could have been handy for you. Mentioning that can alter the measure setting.

Did you ever get the lid under control and the proposed reduction system working?

Max

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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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