Hi all,
I can’t believe it worked so good… I demonstrated the unit in front of 30+ people at the Baja Permaculture Convergence this weekend. We literally finished the build at the last minute, and I was prepared to give excuses on why it wasn’t “quite ready.” or, that the generator was old, and needed to be tweaked. But it worked, and worked very well! I was able to a get 2kW load on a 4kW Onan with CO… Everybody clapped, and cheered… very cool moment. Videos will be coming in the coming days.
However, there were several problems when people weren’t around, and I am trying to get to the bottom of it. I also did something very stupid, and had my first KABOOOOM! event.
Here are the problems:
- After two different start-ups, I was not able to produce good gas any longer, and my third attempt yesterday, for a few friends was not successful. I could never get a flare. The smoke would not ignite. I have some ideas on the problem, but wanted to ask the DOW members about your thoughts.
My ideas:
– A large proportion of ash accumulated after two start-ups, as I let the charcoal smolder out on shut-down, perhaps the charcoal burned for many hours afterwards, and left a bunch of ash in the combustion zone???
– I filled the propane tank to 3/4 full and then drove 50 miles to the convergence. All the bumps and vibrations may have stratified the charcoal sizes. The tiny bits (1/16th of an inch) moved it’s way down, and the large pieces (almost 1 inch) moved upwards.
– Instead of making my own charcoal, I purchased large sacks of carbon, here in Mexico. It’s the same stuff they use to BBQ chicken or beef… It looked pretty good to me, and I didn’t see many un-pyrolized pieces. However, they also didn’t have that "clinky glass’ sound when I dropped them. Perhaps they weren’t fully done.
– The flare was not pure blue… This was a bit of a shocker… The flame looked very much like the wood gas flares I made before the switch to charcoal… The flame was blue with a mixture of that “Halloween orange” color. To my previous point, maybe there were some hydrocarbons left in the carbon???
– As I mentioned, the third try was a failure… I noticed a lot of condensate on the cyclone. My cyclone is plastic (Dust Deputy brand) and I saw beads of water on the entire surface… I did not see this before, but I also didn’t look for it.
Any insight would be most welcome… The flare didn’t ignite, and the engine would not turn over, but there was smoke.
- After the successful demo, I turned off the blower, closed the ball valve to the nozzle, and just let the flare burn. It was cool to watch a lazy flame just burning… Instead of blowing out flame before i disconnected the hoses, I started to disassemble the system with the flame going. DUMB! Oxygen quickly made it’s way into the system, climbed up the pipe to the flare assemby, and the flame ignited the gas, which then made it’s way down to the final media filter bucket and blew the whole lid off! It sounded like a shotgun blast, and my wife jumped out of her skin. Luckily nobody was hurt… except my pride.
I now understand the full repercussions of letting oxygen into the system. It will forever be scarred into my memory, and will approach this safety issue with full respect, as it deserves.
Conclusions:
Because of my explosion event, I’ve decided that an open-source gasifier – made with off-the-shelf parts and no welding required – would be a bad move. I’m intent on doing an open-source gasifier, but one with metal, and plenty of welding… Emphasis on safety. I can just imagine someone building one of these without knowledge of fabrication, gasification, etc. I don’t want that on my conscience.
So, we’ll treat this as an inexpensive prototype that precedes a fabricated unit.
One thing is for certain… It worked well that night, and I am smiling.
Troy