Recharging your active charcoal

[Chilli-CON-Charlie]

Hi again folks, been asked a question to post up here at 420 so here it is.

I read somewhere that u can recharge the active charcoal inside your carbon filter by placing it in the oven for x-amount of time. Is this true?

And if so how long do u bake it for and at what temp?

Your help would be most valuable as Im currently being doubted and tomorrow my pal is off to buy some new active charcoal to fill up a 200mm RVK extraction unit, I would imagine that would be a tad pricey and I would love to save him the time and money.

[highgrower]

There was a post a while ago re this, have a search but i think a normal oven - even the self cleaning ones dont get to the temp u need to get the carbon to burn off the crap and be re-activated - i think some one even tried with a hand held blow torch thing - have a search im sure there were pics as well.

[Chilli-CON-Charlie]

just had a quick search, checked back about a dozen pages, a bit of a piss off really as i typed in the word charcoal and outta all the post that popped up only 5 or 6 headlined 'Charcoal', then i checked google and found one post which said bake for 30 minutes at 350, read a couple more on google that said 'they doubt it could be done in a household oven', but didnt say it couldnt, so now im even more confused, ..

[highgrower]

Heres the thread i was remembering:

http://www.uk420.com/boards/index.php?show...=62215&st=0

But to quote:

Carbon becomes activated in the absence of air and with temperatures of 600c +

" Carbonization: Material with carbon content is pyrolyzed at temperatures in the range 600-900 °C, in absence of air (usually in inert atmosphere with gases like argon or nitrogen) "

carbon + air + heat = carbon dioxide

You want a physical reaction not a chemical reaction

[Chilli-CON-Charlie]

Heres the thread i was remembering:

http://www.uk420.com/boards/index.php?show...=62215&st=0

But to quote:

Carbon becomes activated in the absence of air and with temperatures of 600c +

" Carbonization: Material with carbon content is pyrolyzed at temperatures in the range 600-900 °C, in absence of air (usually in inert atmosphere with gases like argon or nitrogen) "

carbon + air + heat = carbon dioxide

You want a physical reaction not a chemical reaction

Dam looks like that idea is outta the question then, cheers for the help mate u been most kind

[highgrower]

Dam looks like that idea is outta the question then, cheers for the help mate u been most kind

No probs thats what this sites about.

[compostverte]

A pottery kiln would be handy for explaining high power consumption as a bonus.

[thothamon]

As the carbon heats up it will change shape, causing the release of all the !@#$

its absorbed. Not a pleasent smell, even at distance.

[ripthedrift]

There is a simple and easy way to recharge you charcoal to reuse it or recycle it

Charcoal is carbon. Activated charcoal is charcoal that has been treated with oxygen to open up millions of tiny pores between the carbon atoms.

The use of special manufacturing techniques results in highly porous charcoals that have surface areas of 300-2,000 square metres per gram depending on how it was produce .These so-called active, or activated, charcoals are widely used to adsorb odorous or coloured substances from gases or liquids. ­

­The word adsorb is important here. When a material adsorbs something, it attaches to it by chemical attraction. The huge surface area of activated charcoal gives it countless bonding sites. When certain chemicals pass next to the carbon surface, they attach to the surface and are trapped.

Activated charcoal is good at trapping other carbon-based impurities ("organic" compounds ), as well as things like chlorine. Many other chemicals are not attracted to carbon at all -- sodium, nitrates, etc. -- so they pass right through. This means that an activated charcoal filter will remove certain impurities while ignoring others. It also means that, once all of the bonding sites are filled, an activated charcoal filter stops working. At that point you must replace the filter.

So the carbon is basically blocked with organic solids , to release this organic fraction we need to introduce the carbon to something that will eat the organics so it becomes unblocked freeing up the blocked pores.

To do this we need to make the carbon part of a bio filter to utilise beneficial microbes as in worm composter , anaerobic digestion or in bokashi

Digester (which is anaerobic digestion) so during all of the above process’s there is a liquid (lechate run of ) that is the bi-product of the over all reduction in volume , chemical and biological actions of the above .

The filter is made up of just two things dry clean sand (not beach sand as to salty) and or a mixture of composted tree bark fines (smaller size that’s be graded ) this is how the layers are constructed.

The basic filter is 4/5 inches in depth of sand mixed with your used charcoal at a ratio of 50/50 , on top of this you place a layer of tree bark fines (does not matter how wide it is just scale up or down depending on the size of your worm composter/digester/bokashi unit ) .

And using this filter to clean up the liquid as it filters through the medium ,it takes about a week for it to become biologically active with anaerobic bacteria , the microbes feed on the suspended solids as the lechate filters through and with in a few weeks the charcoal is clean and working efficiently again.

There are a few other benefits to using this in so much as the bod (A measure of the amount of oxygen consumed by micro-organisms in breaking down organic matter in effluent during a certain period) is reduced ,the lower the figure the better (water has a low bod of 4/5 while raw sewage sludge or land fill lechate can be has high as 2/3000) the lower it is the better for your plants when used as a tea type feed.

So as you are going to be replacing you filter every 9/12 months depending on the type (approx) , this will then allow the reuse of the charcoal as you bio-filter .

To use your charcoal again just dismantle your bio-filter by first removing your tree bark layer and tipping the sand charcoal mix out , screening of the sand , allowing the charcoal the air dry and finally stick it in the oven on a medium heat for an hour or so , and there you go clean fresh charcoal.

The liquid run off or tea is in a much more beneficial state than just using the unfiltered liquid that in some case may have undesirables in it , you could use a small pump to oxygenate the liquid to really clean it up and encourage an aerobic bloom .

Especially with the worm tea as this will have lots of dormant beneficial microbes , fungi spores (from the tree bark composting process) that will bloom when oxygenated .

its not complicate and as your only changing your carbon , say on a yearly basis .. you have the time for a complete cycle.

ask away if your not sure ..but i have tried to keep it as simple ...

B)

it does work ... we used to use it in massive bio-filters in our composting (500 cubic metre in size ) sites for cleaning the run off liquid and as an air scrubber to remove VOC's

(volatile organic compounds released during the composting process ) its just a simpler version

e2a of course this is not going to suit every one ....but for those that like to recycle then you will see the benefits of this process and its a win /win situation to

and even if you can't be bothered to screen it out after it still make a really good bio-filter

Edited June 19, 2009 by ripthedrift

[Ganjaman17]

i really like the idea of trying this out as i have all the available stuff knocking around in various places. Nice one for posting that info mate

[susat]

Also I've heard blasting ozone through ur filter will bring it back a fair bit (ozone generator in front of a fan in ducting into the fiter at high dose, in a sealed tent for 24 hours , and make sure you only return after it has stopped for a minimum of 5 hours. Use a pre filter inside ur scrubber. Will be trying it very soon whilst I also blast a tent , it had a bit of powdery mildew so it should kill any nasties then the bleach down!