Lazy Biochar

I have been toying with making biochar.  It be honest it's one of those topics that make my head spin.  What is it? How you make it? Proper way to use it?  It's enough to make a novice say never mind.  BUT my son likes to have his buddy's over and enjoy a fire in our fire pit.  I noticed there is quite a bit of I will call it charcoal (forgive me if this isn't what it is, you know what I mean)  It has been in this pit for months (to dangerous and hot to have a fire in the summer)  I was wondering if I put the charcoal in a bucket and made compost tea with the charcoal would this become biochar?  If the answer is yes.  Do I bubble the compost tea for the normal 48 hours? Any ingredient that is a must for that tea?  Do I put it into the soil wet, or should I dry it out before I put it into the soil?  
I hope this process will work because I don't think I will ever make biochar on purpose.  But if I can harvest the chunks of left over well burned wood, and throw it in some compost tea when I have a decent amount, then I could make my lazy biochar.  Can't wait to hear what the verdict is.  Thanks

Jen, that would work fine.  You can use plain old charcoal and inoculate it any way you like, whether by compost tea, or throwing it in a compost pile, or in the chicken run, or peeing on it.  I don't think the people that created terra preta worried about any of this anywhere near as much as people do now :)  I make charcoal all sorts of ways at all sorts of temperatures.  I inoculate it in any way that strikes my fancy at any given point.  It's all helpful in my opinion.  One of the best things that anyone ever told me was "don't let perfect be the enemy of good".  Since then I strive to do things that are good and I accomplish far, far more than I did when I tried to get everything perfect.

Here's Stephen from Skillcult (who does a lot of different biochar stuff).  Here he is harvesting biochar in the forest after a forest fire.  

just wondering what is the difference between biochar and charcoal?
I saw one video where biochar was made in a sealed barrel with very small hole in the top, this seal barrel filled with pieces of wood was placed in a larger barrel and the space between them was filled with pieces of dry wood and set on fire to cook the wood in the sealed barrel.
is bio char and charcoal the same?

bruce Fine wrote:is bio char and charcoal the same?

Phew, big discussion point but I'll have a go. Feel free to add or correct, folks.

Biochar, as defined in this forum, is charcoal from natural wood/plants that has been infused, in its gazillion tiny little nooks, by nutrients and microorganisms. Char added directly to soil will eventually become biochar; it's a natural process, but takes time and may suck up nutrients for a couple of seasons. Grinding it fine, infusing it with nutrients, fertilizer, and microorgs before adding it to soil gives benefits on a fast timeline, without the drawback of nutrient suck. Since the char structure doesn't really break down past a certain point, its benefits as micro-habitat and two-way nutrient and moisture sponge can last for decades, or perhaps centuries. It's atmospheric carbon, sequestered and utilized by living soil via fire. Pretty cool.

More refined methods of making char capture more of the complex smoke/acid elements (fertilizer potential) and perhaps have a better structure for microorganisms. The slower, more oxygen deprived, and smokier the better; but it's a rather nasty and stinky process. Everybody downwind knows you're doing it; but if you can recirculate the stinky gases into the fire for heat, it's a lot cleaner.

My 2 cents. Likely far short of a dollar.

bruce Fine wrote:just wondering what is the difference between biochar and charcoal?
I saw one video where biochar was made in a sealed barrel with very small hole in the top, this seal barrel filled with pieces of wood was placed in a larger barrel and the space between them was filled with pieces of dry wood and set on fire to cook the wood in the sealed barrel.
is bio char and charcoal the same?

People argue this pretty strenuously, but my view is that charcoal is just charred wood. After it is inoculated it becomes biochar. So in the video you saw, I would call it charcoal when it came out of the retort, and biochar after it was inoculated by compost, compost tea, urine, chicken manure, or whatever.

To pile on ...

There is some serious science that can go into making charcoal.  The temperature, time, moisture content during the retort process can affect how thoroughly the wood is reduced to its carbon lattice structure. Other aspects of the retort process can capture wood vinegars that are useful for many things. The fancier the process - think "Activated Charcoal" - the greater the surface area and, essentially, the effectiveness of the charcoal.  Do you need Activated Charcoal to make BioChar?  Nope, but it would be better.  Should you care?  Probably not.

Although its not technically charcoal, I consider coffee grounds to be proto-charcoal or lazy bio-char.   Sure, its not the real thing but a) its carbon b) its got nitrogen in it.  One of the big fears of non-inoculated charcoal is that it will suck the nitrogren out of your soil -not so with coffee grounds!  Will it last as long as genuine charcoal?  Meh, probably not.  But its free, widely available and easy to to disperse.

So yeah, just add black stuff.

is biochar and charcoal the same?

 It depends on who you are talking to.  Technically no, they are not the same.  For one, as mentioned, bio-char is char that is inoculated with biology or nutrients of some type. For another, Biochar is made in a low to no oxygen environment with controlled heat, the same is generally not true with charcoal made in a forest fire, fire pit, or wood stove.

I agree with everything else that Douglas Alpenstock wrote but my understanding of the following is different:

The slower, more oxygen-deprived, and smokier the better; but it's a rather nasty and stinky process. Everybody downwind knows you're doing it; but if you can recirculate the stinky gases into the fire for heat, it's a lot cleaner.

Unlike the making of char for biochar, the making of charcoal, as in making it for industrial use or for home heating was designed to trap the volatile oils in a lower temperature process and it is a smoky process and this was common in the past, but a good retort or any other properly designed 'machine' meant for the production of biochar will not be smoky or stinky much at all.  The one I have made smokes very little, the fire burns hot and clean and as the process goes through its cycle the volatile gasses within the chambered wood are released to the outer fire to increase its efficiency and even the trench fires that I make it in create very little smoke considering the amount of wood burned, and the amount of charcoal made.  

I agree with Eliot Mason, here:

There is some serious science that can go into making charcoal.  The temperature, time, moisture content during the retort process can affect how thoroughly the wood is reduced to its carbon lattice structure. Other aspects of the retort process can capture wood vinegars that are useful for many things. The fancier the process - think "Activated Charcoal" - the greater the surface area and, essentially, the effectiveness of the charcoal.  Do you need Activated Charcoal to make BioChar?  Nope, but it would be better.  Should you care?  Probably not.  

But I would amend the last statement by saying possibly not, and further amend it by saying that activated charcoal is an industrial process involving steam after the wood is preheated to the point of char.  This type of process is 'similar' to what many backyard people do if and when they quench their char making process, but the industrial process is with extremely high temperature, oxygen-deprived steam, instead of water.  The water that I use in my trench fire, for instance, will cause some of the same effects as it turns to steam causing the exploding of the carbon matrix, but mostly the water is just putting the fire out and eliminating oxygen so that the char does not keep burning and turning to ash. I will add that I say possibly not, because there is a limit to what types of char can actually be infused with carbon.  Certainly the more activated the carbon matrix is, the more pore space is available to the incoming inoculation of biology, and this should be as much a focus as your time and energy allow, as it does indeed increase the quality of the end result. The video I posted earlier is one in which char from a forest fire is collected for use in a garden.  This guy piles heaps of food waste he gets from restaurants on top of his char in pits, or just mixes it into the soil and anticipates and allows for the initial nutrient drain that it causes in the soil.  The char he collects in the video is in various levels of being like good biochar material, in that much of it is likely to have not had it's volatile oils burned out of it, or offgassed from heating, and thus there is a lot less pore space available for biology.  Is that bad?  Nobody can say to what degree, as the studies are not done, but i think the more habitat space that is in our char the better, and the more the wood is heated to just the carbon matrix, the less wood that can break down in the soil (robbing the soil of nitrogen in the process), and the longer lasting the carbon is in the sequestered system.

I wouldn't go as far as to agree fully with any of this part of Eliot's post, however:

Although its not technically charcoal, I consider coffee grounds to be proto-charcoal or lazy bio-char.   Sure, its not the real thing but a) its carbon b) its got nitrogen in it.  One of the big fears of non-inoculated charcoal is that it will suck the nitrogren out of your soil -not so with coffee grounds!  Will it last as long as genuine charcoal?  Meh, probably not.  But its free, widely available and easy to to disperse.

So yeah, just add black stuff.

 In  my understanding, there is really no correlation or comparison of coffee grounds to biochar.  Coffee grounds do indeed add nitrogen and other nutrients, are they are 'black' (well dark brown) and do have a bunch of carbon to add to your soil, but they do not take on nutrients or create habitat for beneficial microbes in anywhere near the same capacity that would make this idea of substitution accurate in my understanding.  Charcoal can last hundreds of years if not millennia, whereas coffee grounds are unlikely to last more than a year.  One thing that should be considered about coffee grounds is their high acid content, which can significantly alter your soil PH. Coffee grounds are best, in my opinion, added to compost as an additional source of nitrogen.  They are indeed often freely available in quanity, but unless they are organic, they are one of the most chemically saturated substances that exist in the human food chain, and i thus avoid them unless I can find a quality organic source.

Thanks to Roberto for making some serious additions to this conversation and sharpening places where I, in character with this topic, am lazy.

As to the "probably not vs possibly not" caring about activated vs normal charcoal-  If making charcoal, trying to "activate" it seems totally worthwhile.  But if someone gave me some plain charcoal I wouldn't turn my nose up at it.  As Trace points out, Terra Preta happened without any such concerns.

I found this "Cody's Lab" video to be informative on the differences between normal charcoal and activated charcoal, especially the resulting difference in absorption:  

As to coffee grounds ... yeah, I'll confess I'm pushing the "Lazy" label pretty close to "Careless". I suppose my point is that while charcoal is good, innoculated charcaol is better and innoculated & activated charcoal is best, throwing cofee grounds around ain't bad considering the total lack of effort, energy, etc involved. Its just an intuiition - perhaps totally unfounded - that the roasting and brewing process removes a bunch of organics and leaves some amount of carbon matrix behind - maybe 1% of what you could get, but something.   I'd like to dry coffee grounds and then put them in a retort and see what happens (density of coffee grounds is much higher than I could achieve with wood or wood chips, thus there's some efficiency here), but for now I'm just collecting and spreading the grounds.

As to the biological and chemical characteristics of coffee grounds, I'll cite a Redhawk thread: https://permies.com/t/45126/Coffee-Grounds and suggest that a) I probably should have left this topic there and b)  further conversation of coffee grounds belongs there (but I'd really like to resolve the difference between Redhawks statement "There are no Herbicides used in coffee growing" vs Roberto's assertion of "chemically saturated").

this is the only kind of biochar i ever make, the benefit is obvious- because it's easy.
easier for me because its just waste, i have a lot of fires already, i already have the basic stuff afterwards.

.... whatever is left over is...well not "biochar" specifically, but a close enough cousin once you inoculate it with good stuff.
i realize some would not consider this to be the proper way, but for me its good enough. actually much better than good enough =) and bonus it doesnt take very long to make.

as above "terra preta" is probably the proper name for this, maybe. well i would call what i make something more like a terra preta, have a really big fire and actually cook the screened native soil too, above it, or by throwing it directly on the fire. this will sterilize the soil, so afterwards adding finished compost, inoculates or other living soil is needed. scoop all this from a fire pit and you have something good for filling a raised bed or whatever else.

Origin of the term Biochar. Before there was "Biochar" there was "Agrichar". The Terra Preta community dedicated to achieving Terre Preta Nuova by reverse engineering the Amazonian Dark Earth (ADE) phenomenon coined the term "Agrichar" meaning charcoal you would want to use in an agricultural context. I miss those times, the term agrichar was easier to communicate than biochar is.

In 2006 some Australians members of the TP community saw the opportunity to make some money and commandeered the term Agrichar, trade marked it, restricted its use. The meaning of Agrichar became charcoal made by slow pyrolysis that has been enhanced in proprietary ways to perform well ag-wise. The rest of us had to come up with a new name, and biochar is the term we chose. It still upsets me! Fast forward 13 years to 2020, and the term "Agrichar" has disappeared from use.

Biochar, like the term scientist, can cover a wide range of qualities and qualifications. If my life hinges on understanding soil science, and I seek out the knowledge, and achieve soil success, am I not an accomplished soil scientist regardless of whether I paid for a degree or not? Maybe even more so? Yet some (me 15 years ago) would say, if you don't have formal qualifications you can't honestly present yourself as a soil scientist in formal contexts (teaching, public testimony, client reports) at least not without speaking to that detail. Does the term scientist become meaningless if we can't agree on one shared definition?  

It's kind of the same with biochar. I take the position that if I am using charcoal to accomplish improved soil health (or animal health, or compost health), I feel perfectly fine using the term biochar regardless of feedstock, ash content, volatiles content, resulting molecular state (torrefied/amorphous/graphene), process (hydrothermal-carbonization/pyrolysis/gasification/combustion), or post process treatment (seasoning, amending, activating, charging, washing, acidifying, rinsing, crushing). However what I use as biochar often will not meet the definition of biochar established by the International Biochar Initiative, nor will it meet the definition we use among ourselves locally a tribal understanding that without inoculation, biochar is just charcoal. And there are consumer protection issues when even highly caustic black ash, even char stinky with smokey smelling tar, even charcoal made irresponsibly, can be labeled biochar, thus the need to steer folks towards IBI certified biochar products, and towards the inoculated or composted variants favored within our permaculture community as the only biochar worth having. From my perspective, I see no hard and fast rules defining what biochar as a material is and isn't, but I respect anybody who has settled on a definition that works for them, that they are comfortable with.

Before there was "Biochar" there was "Agrichar".

 Thanks, Philip Small for entering the conversation and sharing this.  I remember those days now but had forgotten that I had used the term myself, as it has been quite a while.

Biochar, like the term scientist, can cover a wide range of qualities and qualifications. If my life hinges on understanding soil science, and I seek out the knowledge, and achieve soil success, am I not an accomplished soil scientist regardless of whether I paid for a degree or not? Maybe even more so? Yet some (me 15 years ago) would say, if you don't have formal qualifications you can't honestly present yourself as a soil scientist in formal contexts (teaching, public testimony, client reports) at least not without speaking to that detail. Does the term scientist become meaningless if we can't agree on one shared definition?

 Yes the white coats have been unjustly annointed the gift of sole proprietary use of the term science.  Experimentation and observation-without strict controls, but repeated for clarification-are what brought humanity through far greater advancements in improving us culturally over the millenia in my opinion.

I feel perfectly fine using the term biochar regardless of feedstock, ash content, volatiles content, resulting molecular state (torrefied/amorphous/graphene), process (hydrothermal-carbonization/pyrolysis/gasification/combustion), or post process treatment (seasoning, amending, activating, charging, washing, acidifying, rinsing, crushing). However what I use as biochar often will not meet the definition of biochar established by the International Biochar Initiative, nor will it meet the definition we use among ourselves locally a tribal understanding that without inoculation, biochar is just charcoal.

 Interesting. Do you put it into the soil without inoculating it, or do you simply call your char product biochar before inoculation?  

I found this "Cody's Lab" video to be informative on the differences between normal charcoal and activated charcoal, especially the resulting difference in absorption: https://youtu.be/GNKeps6pIao Embed this video

Very cool vid, Eliot!   I likey.

As to the "probably not vs possibly not" caring about activated vs normal charcoal-  If making charcoal, trying to "activate" it seems totally worthwhile.

We are in agreeance here, Eliot, if by what you mean is spending the time to make biochar, rather than charcoal, or in activating it, even slightly, rather than leaving it unactivated or simply using charcoal from a fire pit, as activating it (or even going through a more advanced process of creating a higher burn off of volatiles) clearly increases the surface area significantly.  

I think it would be interesting if Cody's experiment had been more controlled from the start, meaning that he had a better quality retort made char without the oils, and had used equal volumes in his various test samples to match a given sample of commercially activated purchased carbon, and weighing them before the experiment.  if he then washed, rinsed, and dried all the samples, he would have created an even moisture content between them, to begin with.  This would eliminate much of the ash question as well as the possibility that moisture, caused by the steam, was an issue in increasing the mass. The proof is truly and clearly in the pudding here, though, when it comes to absorption. Very cool to see this backyard version of the industrial process.

But if someone gave me some plain charcoal I wouldn't turn my nose up at it.  

Me either.

As Trace points out,Terra Preta happened without any such concerns.

Maybe... but, that seems to me to be making an assumption about the sophisticated nature of the people who came up with the original process and their ways of observing and experimenting that I would be unwilling to venture.  So far as I understand and remember (and I've read about it quite a bit), the char in terra preta appeared to be made in an oxygen-deprived environment, and, in my mind, would have been more likely done (in my opinion-but also an assumption) in trench fires (or a pit version), as is done by Stephen from skillcult in this vid:


The constant attempt of the ancient South American jungle to regrow into the garden clearing would have provided a steady source of both source wood for charcoal as well as inoculants, and the pits could be permanent fixtures if earth, wet green material or water (preferred) was present to snuff out oxygen.

As to the biological and chemical characteristics of coffee grounds, I'll cite a Redhawk thread: https://permies.com/t/45126/Coffee-Grounds and suggest that a) I probably should have left this topic there and b)  further conversation of coffee grounds belongs there (but I'd really like to resolve the difference between Redhawks statement "There are no Herbicides used in coffee growing" vs Roberto's assertion of "chemically saturated").

I'll start by saying that chemicals are not limited to herbicides.  Coffee is a substantial perennial shrub and thus would not require a lot or any herbicides in production.  The primary toxins are pesticides.  Many pesticides are neurotoxins, and or have been proven carcinogenic, or have shown other detrimental effects on human health.  I won't elaborate beyond giving an article that details the chemical situation in coffee:  Tox Free Family;  Coffee and Pesticides  There are other resources available in a google search for: coffee pesticides

Thank you everyone for all your thoughts, information, and scientific knowledge.  I  may actually make biochar in the future, I would use the pit method so I don't have to buy anything.  For now I will inoculate what I have and call it good.  I will inoculate it with compost tea, because I do that anyway. My question is, is 48 to 36 hours long enough?  Can I use the liquid in my garden, or will that be a bad idea?  How about in my compost?  Would that be a better option?  
Trace I like your saying.  Perfection can get in the way of production.   Thanks all.

Jen Fulkerson wrote:Thank you everyone for all your thoughts, information, and scientific knowledge.  I  may actually make biochar in the future, I would use the pit method so I don't have to buy anything.  For now I will inoculate what I have and call it good.  I will inoculate it with compost tea, because I do that anyway. My question is, is 48 to 36 hours long enough?  Can I use the liquid in my garden, or will that be a bad idea?  How about in my compost?  Would that be a better option?  
Trace I like your saying.  Perfection can get in the way of production.   Thanks all.

36 or 48 hours would be fine, the charcoal would be well inoculated and the remaining liquid will still be wonderful compost tea. All the charcoal is doing is providing housing for our micro beasty friends (I know, there are probably subtle energetic properties to char that many of us fail to appreciate). It only "steals" nutrition if its un-inoculated because the biological bloom it fosters feeds on the same foodstuffs as plants until the population stabilizes and the plants have access to their dead

i am certainly not an expert when it comes to specifically bio char or terra preta, but it fits with the natural way of land clearing and can be quite simple.
throwing a lot screened dirt on the end and letting it smother it all night is a good way to go because it also cooks your dirt.  its also good if its out of season, to make sure its completely out before bed.

often its a long process, if you make big moves on landscaping, like an all afternoon fire, and theres first dragging everything over as you go along. so this is the basic gist of how they did it back when, and also adding fresh and partially composted stuff and food waste, as well as new loads of fresh stuff as it got cleared. that green stuff doesnt always burn through, and theres moisture in the leaves and the compost they would put on there.

so yeah basic simplified way to make terra preta - burning piles of cleared brush thats dry, adding lots of fresh stuff and also compost (towards the end) as well as drier stuff, and then putting a large amount of screened soil on the very end, after it rages for a while. now add whatever else you have to inoculate it and also finished compost or good soil if you have some.