Hello, all. My name is Bill and I can’t tell you how much I appreciate the work you pioneers are doing with Gary’s charcoal gasifier. And Gary’s decision to open source his design and freely share it is a testament to his moral character. That more than anything impresses me and gives me hope for the future.
Long story short, I’m working with a friend of mine on a gasifier that will gasify any feedstock that is gasifyable, not just wood. My approach is to use an external heat source to produce dirty, tarry producer gas, then use that same heat source to clean the gas up for the engine after it comes out of the chamber. I’m also incorporating catalysts to assist. My heat source started out as a rocket stove, but we wound up building a better stove to accomplish this. The catalyst to crack tar molecules is iron.
What does this have to do with charcoal gasification? Well, considering the high heat needed to clean up producer gas, I had to prepare for failure and find an alternative method to accomplish a universal-fuel gasifier. Failure is just not an option for my partner and I. And the research I did, just in case my original method failed, brought me here to the great work you all and Gary are doing.
My theory was that the dirty producer gas we created by externally heating a container of biomass could be cleaned up by running it trough your charcoal gasifier. The hot charcoal should be enough to crack the tar molecules into short chain molecules suitable to fuel an engine, if we filter it up through your gasifier.
Why do this when charcoal itself produces clean producer gas? Because a setup like I’m describing would allow you to make clean, engine-ready producer gas from wood, grass, weeds, plastic, used motor oil, waste paper/cardboard, animal/human manure, and agricultural waste, to name a few. The feedstock you can use would be readily available in most parts of the world and plentiful. We could stop throwing most of our trash into landfills and turn it into fuel to power our lives.
Until tonight, this was just a theory with nothing I had found in the history of gasifiers to back it up. I just found something to suggest this is possible, though.
Excerpt from what I found:
Perth, Western Australia, 1981. A Toyota diesel Land Cruiser fitted with dual firebox gas producer being tested. The unit has both an updraft generator for charcoal fuel and a downdraft generator for wood chips. The two are coupled so that gas from the wood chips passes through the burning charcoal and is purified of tars before entering the engine. For short runs, only the charcoal generator is lit. It is efficient, quick starting, and handles variable loads with little change in gas quality. For long runs, both fireboxes are lit. The gas formed by the downdraft generator supplements that from the updraft generator. The downdraft generator has three rows of air inlets (tuyeres). By unplugging the different rows a wide array of fuels and horsepowers can be accommodated. The unit shown was sized for use on an 8-ton truck.
This is a description of what I’m talking about. It suggests that it is possible to use your charcoal gasifier to clean up dirty producer gas made from just about any gasifiable feedstock.
Were I to try it this way, I would put a second container on top of the charcoal gasifier. A second set of raw feedstock would be in that top chamber. I would run a pipe from the top of that upper chamber to the bottom of the charcoal gasifier. I would pipe the engine exhaust into the top chamber, to push the producer gas into the charcoal gasifier. The waste heat from the gasifier should cause the material in the top chamber to off gas tarry producer gas. By the time it comes out of the charcoal gasifier, it should be clean.
I hope you all see value in this and pursue it.
Also, in my research, I came across another nugget you all might be able to use. Hydrogen can be a bigger component of the gas from the charcoal gasifier. You will need to add a little steam to achieve a more energy-dense fuel. Also, the catalyst to break the hydrogen from water is nickel. Perhaps a nickel screen in the gasifier which the gas has to go through would help separate the hydrogen from the oxygen. The oxygen should bond to carbon molecules in the gas. The additional hydrogen should help power the engine a bit more and ensure a clean burn of the producer gas in the cylinder. A small container welded to the charcoal gasifier, with a hole in the gasifier above the water line for the steam to enter, should supply the steam. Or, put wetter material in the upper chamber to supply extra steam.
Last, but not least, you should be able to make charcoal from materials other than wood. Bio-briquettes can be made from a multitude of things, like grass, paper/cardboard, sawdust, weeds, ect… (Look up bio-briquettes and charcoal bio-briquettes) When making charcoal, you might consider running the “smoke” through your charcoal gasifier, both to clean it up so it doesn’t pollute the air and to increase the amount of producer gas out of the charcoal gasifier. Either that or pipe it to the fire below the charcoal making retort. You can get the wood that is being turned to charcoal to partially fuel the flames in the charcoal maker, which should consume less wood during the charcoal making process.
Like I said, I’m attempting this universal fuel gasifier in a different way, but I wanted to share this with you all in the hope you find the info useful and it furthers your efforts. You all are doing fantastic work here. Just proves we don’t need those ass-clowns in Washington to solve our energy problems for us. If we want it done right, we’re going to have to solve it ourselves. So, lets get back to it.