woah. Thanks. I was thinking to get the superheated steam you needed high pressure but you really don’t. That means this method works and it is a lot safer and easier then I was originally thinking:
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Hi Kristijan,
Yes, the slipped charcoal is more activated
All depends on what the adsorption would be needed for.
You can use steam to activate, CO2, oxygen… a bunch of products.
The activated charcoal would need to be within certain specs for ashes, and a neutral PH value.
To many variable possible to explain in few words …
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Hi Sean, sadly but no, the water would boil of beforehand.
If i use steam, then first steam generator and pass that thru a coil in the same oven as the retort with charcoal is…
The output from that retort is high quality gas Hydrogen/CO.
I turn in first step the temperature to around 750 C for making charcoal, the gas becomes smokeless and little to none, then i increase temperature to 900/1000 and ad steam thru the coil.
The steam will eat away the carbon untill a certain degree of porosity is reached.
To play with how much steam per time / quantity charcoal.
You can ad chemicals to the water for generating the steam and that will affect the wall structure / adsorption quality.
Ashes are washed away with hydrochloric acid, flushed / washed untill the PH is neutral, then you have excellent activated charcoal.
There is a lot of information available on what the exact criteria are, same goes for different recepy’s
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Thanks! That was a great overview of the process. I knew it was controlled but I didn’t know the temps. The starting material has an effect on the end result according to the water guys, like coconut (fruit), coal, and wood all have different targets for filtration because of the initial porosity which I kind of guessed. I am also guessing grapevine or willow would work, but it would have to go through a more scientific process then I am currently capable of.
I was just poking around looking around trying to figure out the difference between a water softener and a flushable carbon filter. IE can you convert a water softener to a flushable GAC (granular active carbon filter). The closest I found so far was this PDF which talks about particle size, media needed and flow rates especially for backwashing, but it sounds like he is using it in a water softener. (It is more then just replacing the media, but I am still trying to figure how much more.)
1995 - Nov - Sizing Whole House Softeners and GAC Filters.pdf (597.3 KB)
I was trying to figure out how to get the gas out and do something useful with it and the excess heat… In the process, I think I =almost= found a good analog temperature gauge for this process. 
Melting Temperatures of Common Metals ;
Aluminum: 660°C (1220°F) ;
Radium 700°C (1292°F) ;
Barium 727 °C (1341 °F) ;
Strontium 777°C (1431°F) ;
Californium 900°C (1652°F) ;
Brass: 930°C (1710°F) ;
Neodymium 1024°C 1875° ;
Carbon Steel*: 1425-1540°C;
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Sean, yes, great thinking.
the gas output from such unit is well worth storaging it, i sometimes use it as accelerating gas for an engine in certain conditions
( from bottle to injection nozzle )
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It probably is worth storing, but to be honest, I was thinking I could melt some aluminum down at the same time. Then I was looking up other metal melting temps to see if I could melt something else down as well. 
How long does it usually need to be steamed? I am assuming 5-10 minutes and It doesn’t take long to go from 0-900/1000 with bone dry char. I assume there is a way to tell when it is done, but it could purely be a guessing then testing game which means everything needs to be consistent, and I would use propane.
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yeah… there comes the culprit 
of not knowing yet … the dryer the carbon, the less easy to heat it up…
In my system i inject steam when the oven is still at temperature.
To determine a suitable activation level i use a certain amount of water/steam with each certain amount of charcoal , in a given time…
For each type of raw material, you’ll need to test and check results, create your own baseline.
Once you have an setup that works, then its easy to calculate values / energy’s needed.
Further: the pyrolytic gas is actual able to go hotter than lpg/propane/butane…
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That one gets me everytime. 
You make it sound easy, but I know better. But the more I think about it, the less perfect it actually has to be. The water is fine. This is just in case organic chemicals made it into the water supply, and maybe filter out some of the calcium.
It makes sense since it is high in hydrogen content.
Oh, is it better to use wet or dry wood to start? When I was doing the grapevine and willow for art charcoal, I peeled it and used wet material because someone on the internet said it worked better to make softer grade of charcoal. I didn’t seem like it mattered to me because it shrunk in the retort. I would rather cut it now, let it air dry for a the winter and the bark will fall off.
I just have a ton of stuff on my plate right now. I was going to buy my way out, if I figured out the water softener part, but a very quick google was coming up with 300 bucks for the 1 cuft. I am not spending that much.
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Isn t it easier to use the pyro gas in the process so you can cut off the propane or electric heater?
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It would be less expensive, but I don’t know if it would be easier. The goal is to consistently replicate the results. Since it starts from cold, the heat source would have to change, it adds complexity and possible variables. I would think it would be something to try after establishing the base data for the material.
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Charcoal is produced at much lower heat. Activated charcoal and Biochar is the same thing. Made with pyrolisis under high heat that causes micro pores. These capture impurities when used as filtre or consumed. Biochar is used as soil enhancer and when attempting to create Terra Preta.
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