The Miracle of Gasification

[Eric Johnson]

Here's a couple shots of my gasification chamber (porno for pyros) going pretty well. It's hard to get a good pic, but one is with flash and the other without. The point of gasification is that the smoke all gets burned up, so that none goes up the stack. If you don't see any smoke in the gasification chamber, you're getting a clean burn. There's no smoke visible in the flash shot, even though the flames are much bigger in person.

The firebrick isn't glowing orange yet because I just fired it up.

 

[Nofossil]

Very cool. When I first got mine, I'd hang around just to listen to the rumble.

I had exactly the same massive piece of refractory cement. Seems to take forever to heat up, and it's a pain to clean the ashes - especially when you have to slide it out to clean the extreme back. By the way - my thinner curved piece finally cracked in two.

I have another thread where I got some help in finding materials for my new and improved combustion chamber. There is a picture of it out on the floor before I put it in the boiler. Below is a picture of it in place.

Don't know about this one yet, but in the previous one, the 2 1/2" thick firebrick would get so hot that you could literally read a newspaper by the glow.

 

[Eric Johnson]

I've got a few years before mine disintegrate, nofossil--plenty of time for you to work out the bugs. But I like the idea and I have a lot of faith in your design skills. Mine would be a lot easier to remove if it was one solid piece instead of three. It looks to me like you're diverting the flame to the front of the boiler. Does that mean you don't want to open the door when the thing is in gasification mode?

Maybe we should do a thread on ways Orlan could improve their design. One thing I'd like to see would be a 1/2-inch well in the front for a conventional temperature/pressure gauge. I have one installed, but unfortunately it's not in a place where there is consistent flow, so the temp side is way off. If you start moving the temp probe around to fool the controller into producing higher water tamps, it would be nice to know the actual temp (in Fahrenheit). Some on-board 3/4-inch tapping for the pressure relief valve on the back would be nice as well.

If anyone's interested, here's a slightly more detailed look at what happens in the gasification chamber.

 

[Nofossil]

It looks to me like you're diverting the flame to the front of the boiler. Does that mean you don't want to open the door when the thing is in gasification mode?

I've NEVER open the lower door when the fan is running, even before switching to this design.

Maybe we should do a thread on ways Orlan could improve their design. One thing I'd like to see would be a 1/2-inch well in the front for a conventional temperature/pressure gauge. I have one installed, but unfortunately it's not in a place where there is consistent flow, so the temp side is way off. If you start moving the temp probe around to fool the controller into producing higher water tamps, it would be nice to know the actual temp (in Fahrenheit). Some on-board 3/4-inch tapping for the pressure relief valve on the back would be nice as well.

Excellent idea - do we have anyone to translate it into Polish?

My additions: Actual US NPT threads on the inlet and outlet. Standard flue diameter (or adapter). V-sloped floor so ashes end up in the bottom. Better 'fire out' logic (don't run the fan on high for an hour after the last coal is dead). Better combustion chamber / labyrinth - quicker starts, easier ash removal.

 

[Eric Johnson]

I open mine up all the time when the fan is running, just to watch it do its thing.

They already made some of those changes. The threads on the supply and return lines are now 2" standard pipe threads. And the flue takes a standard 8-inch piece of black pipe.

I agree on the controller. However, it's a vast improvement over my old boiler, which had controls consisting of 2 aquastats.

Given the current shape of the gasification chamber, it shouldn't be too hard, as you've demonstrated, to retrofit a better labyrinth just by sliding it into the chamber. Actually, I think the ash removal is pretty easy. Aside from having to move the bricks out of the way to get at the hx outlets in the back, I find it easy just to set a wide pan down below the opening and rake the ashes out onto it with a hoe or with the tool provided.

I worked with Zenon on the manual somewhat. After reading over the one that shipped with the boiler I suggested that he hire me to "translate" it into plain English. "Ensuring Right Boiler Exploitation" became "Troubleshooting." You can download a copy of the improved manual on his website. I did the same treatment on the BioMax manual. He hasn't yet agreed to let me expand the current EKO manual to include some of the more useful information that users should have access to, such as the three ways to adjust the air supply, but I'm going to wait until I use the boiler steadily for a few months before making another pitch along those lines. My point was that these days, downloadable manuals are another sales tool, and they should be a source of information, not hilarity or confusion.

Some companies are receptive to customer/dealer suggestions and others are not. But if we can get a collection of ideas together, I'll be happy to run them up the flagpole and see if anyone salutes.

 

[Nofossil]

For me, the short-interval ash removal in the bottom chamber wasn't the problem - I did it much as you do. What aggravated me in the bottom chamber was this:

1) You can't really get the ashes out from behind the big 'cradle' block. Maybe you don't need to, but it felt like I wasn't being thorough.
2) The 'cradle' block is heavy and it's an awkward angle to get it in and out.
3) When it's time to do heavy duty cleaning (all the way to the back), it's really awkward to get the rear curved wall baffle out - it's way back there. It looks like yours is different - maybe you don't have that problem.

In terms of making a mess, getting ashes out of the top chamber is more of a problem. I have to do it at least once a week, and I always get ash dust in the air. I wish that more (or all) of the ashes made their way to the bottom, where they're easier to deal with. Sometimes I also end up with unburned charcoal in the top. If it fell through, the temperature and extra oxygen in the bottom chamber seems to burn them up pretty completely.

I saw a picture of another boiler on this site that had a 'V' shaped bottom in the upper chamber. Seems like that would do it, though perhaps you'd need an inconel or titanium grating to keep the nozzle from getting plugged.

 

[Nofossil]

Though I'd revive this thread with a photo of full-bore gasification using my latest labyrinth. What you're seeing is the return path - the bottom of the labyrinth. The room air has cooled the outside of the alumina bricks so that they're not glowing anymore. Toasty warm. The stack temp is about 260.

 

[Eric Johnson]

That's pretty cool. Except it's different than the original picture, which appeared to force the flames right into the gasification chamber door. In this one, you've got an alumina brick in the way. Anyway, I hope you can get a design that lasts, because I think it's a really interesting possibility.

I don't have the curved baffle that you mention. At least, not that I know about. The only movable parts in my gasification chamber are the three bricks. I agree that they're at a bad angle, but I haven't seen the need to take them out yet.

Maybe having two nozzles makes a difference, but all my ash from the primary combustion chamber winds up in the gasification chamber. When there are few or no coals in the bed, I can rake most of the ash and charcoal down through the nozzles and then out with the rest of the ashes. Maybe that's why I have to clean out my ashes more frequently. BTW, I think my theory about a clean ash pit resulting in a clean burn is valid. So far, at least, that's the way it looks. If I can incorporate raking the ashes out of the bricks every morning when I stoke the boiler up, I think I'll have 'er licked.