I am really looking forward to seeing what you come up with. I had high hopes of building a larger charcoal reactor to run a generator, but it has been pushed way off into the “someday” category.
I had thought about also trying a downdraft, but had not gotten as far as putting together a design. Keep us posted!
Dave, I’ve been thinking about you lately.
On latest news yesterday, they said the fires cover an area eq to 1/3 of my country. Made me realise the fires we had 1 1/2 years ago were small bonfires in comparence.
In the back of my mind I remember you live in the very south, close to Melbourne, right? How close are you to the NSW fires?
I wish you all well and I’ll do some rain dancing for you.
Hi All , Don you really really don’t think that i had thought of that 
There are 2 or rather there used to be 2 Large fire fronts 1 in NSW and one in Victoria where i live , now the 2 larger fires have met up on the border and is now 1 huge fire , trust me there is no way you can even get close to area’s that the fires have been through , police and residents are only just being allowed back to check and even then its not a pretty site , i am about a 2 hour drive from where the fires started i think , and i guess it was just the way the winds were blowing that took the fire front away from us here , there are still a few towns that are still cut off from the outside world and getting air drops of fresh water and food , there are still dozens of smaller but still life threatening fires going on all around Victoria and New South Wales , the last few days we have had a drop in temps and also some rain so that’s helping a lot its just the winds that cause worry .
On another note i just came in from running the generator again this morning and again i have run it right down till the engine stopped , at the moment its too hot to open up , but looking at the micro filter down stream that’s clean but for some reason today the micro cloth is soaking wet , of course living in the clouds my charcoal can absorb a fair mount of water even when stored in air tight metal drums , i guess condensation is to blame as well maybe .
Tomorrow i will be gathering the pipe fittings to convert the 55 gallon drum into a simple downdraft and try at least to get my 4 and 5 hour run times back that i was used too with my propane tank gasifier , i shall post some pics of what i have thrown together as this will be a real simple converstion ! fingers crossed and if i can get 6 or more hour runs i will be over the moon .
O by the way , the Thick-Wall-HEXOLOY-Silicon-Carbide nozzle i got from ebay thanks to Steve [smaresca] is still going brilliantly no wear at all and has been in since oct 2018 and has had many hundreds of hours on it , i have been waiting for it to need changing for so long now as i really want to test out the Tungsten carbide nozzles Bruce kindly posted to me from the USA so next week i shall be putting at least 1 of those tungsten nozzles into the downdraft .
Koen, you just might be correct in your thinking because i have never ever had to empty out ash from below the nozzle , only ever a molten slag mountain around the nozzle tip
Steve there is only smoke haze here and no particles as such floating around , just flying insects 
Dave
Hi Dave, I have been thinking about the white deposit you found in your gasifier and want to propose a possible scenario. There is always some ash in the charcoal and that ash content and amount is dependent on the source material. Grass, bamboo tend to have high ash while wood, especially if there is very little bark, has less. The grasses tend to have high silicone ash while the wood ashes are potassium and calcium based. When you ran your gasifier, the ash typically accumulated in front of, around and underneath the nozzle. I have found this easy to remove, seldom making a vitrified clinker but usually rather soft and crumbly ash. This material is made up of potassium and calcium oxides and probably some silicone. By the way, take some of this ash, wet your hands and rub some of it on them. It really cuts the grease and leaves your hands soft. In your case, the charcoal level kept dropping and all the ash in that charcoal collected near the nozzle. The intense heat vaporized this ash which coated the gas outlet and the filter. I’ll bet the material deposited is either an oxide or a carbonate of potassium or calcium. If it is a carbonate, it should fizz in vinegar. If an oxide it should make your hands slippery when wet. (be sure to rinse your hands real well because oxides turn into hydroxides that dissolve fat, Think LYE) Glad you did not ruin your engine in this rundown. I’ll have to get some of those microtowels and give them a try. Looks like a neat solution.
Take care and thanks for sharing.
Gary in Pa
Hi Gary , Thanks for your input i had been thinking it might have something to do with the amount of garden waste, eg bark and leafs that i carbonize and mix into my normal hardwood charcoal that may be the cause of the white dusting everywhere , but since posting those photo’s its not happened again , but now its gone crazey wet filters and a strong smelling ammonia filters and pipe work ! it does not seem to have a impact on the motor at the moment and i just dry and change out the filters after every run . again this only happens when i do extended run time , if i just run for say a couple of hours its nice and dry and clean no nasty smells or dust .
Rather than start a new thread i wonder if anyone reading this has any thoughts to how they would set up a downdraft , i am going to start on building one today and wonder if it would be better to have the incoming air off set from the gas exit say maybe a few inches to the side so as not to suck directly from the inline incoming air ,i am also thinking that the distance between the nozzle and outlet pipe should have a certain dwell time before exiting the gasifier , thoughts anyone ?
Dave
I decided today was the day i shall start turning this updraft into a downdraft with a simple reversal of the outlet to inlet and and inlet to outlet with just the addition of a downwards facing nozzle and leaving the old nozzle in place and adding ash around it , and of course nothing ever is that simple and things are bound to go wrong , well i just could not get the nozzle to unscrew from its fitting on the bottom of the drum as i wanted to get it out and clean up the molten slag around the nozzle tip and in the end the refractory crumbled away from the galv fitting i had it and then nozzle attached too .
As you can see the nozzle i put in my system in 2018 has lasted really well with no damage at all to the thick wall-HEXOLOY Silicon Carbide nozzle and only the refractory let it down when trying to unscrew it from the male fitting a while go .
Anyway i have been itching to have a play with some more material that Bruce shipped over to me and hope to have a play with that in the next couple of days .
Here is what i have in mind this is a just a simple in my head sort of sketch i want to try out and so can refine it as i go along , this again will be inside a 55 gallon drum with a lock ring lid
You will lose all the cooling affect of the gas going “up” through the charcoal. Are you going to make up cooling rails for it? TomC
Hi Tom , i have a lot of area already where the gas passes through so i dont think cooling will be major problem , i have just made up the nozzle and i have a distance of around 14 inches between the end of the nozzle and the outlet manifold , if that does not work i can adjust the height by using a shorter length.
This is what i have made up so far
If i have to have more depth then i can weld a container onto the bottom of the drum to lower the exit manifold so more charcoal depth is gained without losing run time
Dave
Dave, thanks again for sharing your photos. We really do have some good usage hours between the two of us with these nozzles…I am so pleased with them.
They survive even with extended use…it’s incredible. I think silicon carbide is now the gold standard, for me personally at least. I chipped my own out of the slag a few weeks ago and compared to a new, unused piece; aside from some superficial grime, the used is nearly indistinguishable from the new.
For anyone else interested, they still appear to be in stock and available from the original seller ($10-30 USD, very reasonably priced). I would expect threaded blast nozzles of the same material would be equally successful. Those could be especially useful for a downdraft.
