Definition of biochar

Here is a post from another source.  This is from a group called Carbon Conscious on facebook. I believe that they are commercial producers of biochar.  They admitted that their definition was controversial.  I respectfully disagreed with them.
John S
PDX OR

WHAT IS BIOCHAR?
Opinions vary widely on this topic which creates a lot of confusion.
For this reason we would like to elaborate on what we at Carbon Conscious Creations  consider to be biochar and the reasons why we chose these specific criteria.
-First of all biochar is FULLY CARBONISED biomass, in our opinion this means that the material has been produced at a temperature exceeding at the very least 650°C but preferably more in the 750°-900°C range.
Some people would argue that lower temperature materials are also biochar and many studies include "biochars" made at temperatures as low as 350°C. Such materials are not fully carbonised and contain a substantial amount of remaining volatiles.
Please be aware that a lot of relatively low temperature materials are being sold as biochar these days because conventional charcoal producers are jumping on the biochar bandwagon in an attempt to unload the fine materials (which are too small to be sold as charcoal for grilling) upon unsuspecting customers.
This is one of the many reasons why we encourage people to produce their own biochar or alternatively purchase it from small local producers that make high quality, high temperature biochar from the most appropriate feedstock for your intended application.
Especially the local aspect is very important here because once we start transporting biochar over large distances we negate one of the major benefits of biochar and that is the reduction of atmospheric CO2 levels.
-Secondly biochar is material that has been CRUSHED TO THE APPROPRIATE SIZE for the intended application.
Particle size is something which once applied into the soil doesn't change very quickly. It would take nature a very long time to break up large chunks of biochar into a finer consistency.
Large chunks are a lot less effective on multiple fronts due to the much lower external surface area. Aside from that they have the risk of floating to the surface of the soil where the material serves no function because BIOCHAR IS NOT MULCH!
Instead of relying on nature to break up the material we must crush it ourselves to the appropriate size prior to application, especially in the Mediterranean region where Carbon Conscious Creations is based because we do not have a freeze-thaw cycle which would aid in breaking up the char over time.
The appropriate size depends on various factors such as the existing soil type and what kind of crop is going to be planted. Vegetable farming for example requires a different particle size range than a fruit orchard for example.
Biochar can also be used in water filtration systems, either to purify water intended for consumption or in grey water filtration systems.
Unfortunately there is no "one size fits all" when it comes to biochar and that is why we offer various grades of biochar, ranging from finely ground up to gravel sized.
-The topic of loading the biochar with nutrients and biology is possibly the most controversial and many people would argue that the "bio" in biochar stands for biology and claim that prior to the loading with nutrients and biology the material is just charcoal.
We do not agree with this notion and in our opinion biochar DOES NOT NEED TO BE LOADED WITH NUTRIENTS AND/OR BIOLOGY prior to application for the material to be considered to be biochar.
Here is why: loading the biochar with nutrients and biology is something that is very easy to do in-situ once the biochar has been incorporated into the soil. Loading the biochar in-situ with liquid fertilisers and/or biological inoculants removes logistical complications which saves a lot of time and effort, especially for large scale applications.
Even if we would not load the biochar after applying it ourselves we can not avoid nutrients and biology from ending up in the biochar within a relatively short timeframe compared to its lifespan. For this reason we don't consider the pre-loading of the biochar prior to application to the soil to be essential.
Having said that we do recommend raw biochar to either be mixed into the soil together with HIGH QUALITY COMPOST or that the mixing of the raw biochar into the soil is followed by LIQUID FERTILISERS and/or BIOLOGICAL INOCULANTS.
BEST PRACTICE however would be to add the raw biochar to a compost pile or to use it as a feed additive for livestock. With both these methods the biochar increases the process' efficiency and gets loaded with nutrient and biology at the same time. One major downside however is that these methods do not scale very well and are thus less practical if one needs to cover a large area.
-Lastly we would like to stress that biochar should first and foremost be made from LOCALLY SOURCED-UNCONTAMINATED-LOW VALUE-WASTE BIOMASS such as tree prunings, dry weeds, untreated timber offcuts, dry crop waste etc.
Not from for example coffee grounds which can already be used as a soil amendment just as they are without any processing.
The intended application also determines which feedstock is suitable or not. Hardwoods for example result in biochar with a lower water holding capacity and more importantly a lower plant available water content. This makes them less suitable for field applications.
Hardwood biochar however is more suitable for filtration applications due to their higher density.

They're at odds with most organisations and producers on some of their points. Most of all, their preferred temperature range is too high. Anything over 600 C starts to collapse the porous internal structure and rearrange the carbon into stacked sheets of graphene. 750-900 C will make a big dent in the surface area, and it will also limit the amount of attachment points where all the cool biochemical things happen. Fine if you want precursor materials for things like batteries and supercapacitors, but pretty meh for soil.

The sweet spot for making biochar for soil is more like 450-550 degrees. Even lower temperatures are fine if the material gets "cooked" all the way through (and 350 C is sufficient for full carbonisation). Low temperature biochars do a better job attracting polar molecules, while higher temperature biochars are more effective with non-polar substances.

Particle size has absolutely nothing to do with the definition of biochar as a material. It's an application detail. I put big chunks on the surface of grazing land, and the lack of a freeze/thaw cycle here doesn't bother me because I let the sheep hooves do the work of pulverising it and working it into the topsoil.

I do agree with them on the inoculation aspect...lots of biochar is made and used without being deliberately loaded with microbiology and nutrients. It still fits the requirements of careful production from sustainable biomass feedstock and the intentionality of application in the environment as opposed to becoming a fuel source or industrial reductant.

They would do well to read some of the literature by the gurus in the field, like Johannes Lehmann, Stephen Joseph, Katherine Draper, Kelpie Wilson, and so forth.

I guess I have my own definition that I am happy with.  The term "charcoal" was around for many (hundreds? thousands?) of years before anyone ever uttered the word "biochar".  I don't see any reason to change a long-standing definition to something else, especially in order to commercialize it, so in my mind, biochar is charcoal that has been inoculated.  I don't concern myself with the temperature at which the charcoal is made, simply because I don't have a consistent way of knowing.  I make charcoal with different processes, mostly because I like experimenting with it, but I routinely fall back to the "tilted barrel" method after having tried it once.  I'm very happy with the quality and amount of charcoal I can get with a burn, but I don't know what temperature it is made at.  As far as the size of the pieces, I just put the charcoal in a bag and run over it a few times, so the particle size varies quite a bit.  I know some people say they just let freeze/thaw cycles crush it, but that has never really happened with mine to any significant degree, and living in the freezing ass midwest, we get really extreme freeze/thaw cycles.  I prefer working with pieces 1/4" to 1/2" but I'm not concerned if they are bigger or smaller than that.

I think the terminology of biochar/charcoal is probably the least important part unless you are trying to commercialize or sell it. In general, terminology varies in most languages depending on where you are from. Ask someone from the north about the word Barbeque and they will tell you it's the metal box outside you cook on. In the mid-west they'll tell you that it's a get together with friends and family where food is cooked outside. If you are one of the lucky ones to live in the Southeast, you will rightly know that Barbeque isn't either of those things, but actual meat smoked low and slow by a wood or charcoal heat source, as God intended. As far as this groups definition of biochar goes, I don't like the idea of the size being important, and though not sure enough to argue it, I would say that if charcoal is made correctly, breaking one piece into ten may not give a giant increase in surface area as a percentage, due to the fact that you are only growing by the broken surface area in an already super porous material. Just my .02 cents, and if you don't agree, I'll give you your money back.

Rusty Ford wrote:I think the terminology of biochar/charcoal is probably the least important part unless you are trying to commercialize or sell it.

It's important for the integrity of the market in more ways than one. If we get a bunch of producers making low-temperature charcoal and selling it as biochar, people who use it in soil are going to be massively disappointed because it won't do much good (either because all the pores are clogged with tars and oils, or worse because the feedstock has contaminants). That ends up giving the whole community a bad name and puts folks off something that could really help with their soil issues.

Another related problem is with production methods that create low-quality charcoal (which might be great as cooking or heating fuel, or course). Low temperature systems are prone to releasing lots of smoke and particulates, which aren't good for the environment and especially the immediate neighbours who get tired of taking down their laundry to avoid having it stink. Those of us who are out there "spreading the word" really want to see good fire and good biochar, not clouds of smoke that piss people off and invite Departments of Sad-Making to show up with regulations that hit the backyard and farm-scale producers.

Hm! Looking at the quotes in the OP I think it fits the goal of marketing, which is to promote your stuff as "gold star premium plus that makes you feel obviously superior when you buy it" and diss the competition as back-alley, second-rate counterfeiters who don't know what they are doing and will conn you into buying counterfeit goods. Yup, smells like marketing.

I agree with most of what this guy says, but I disagreed with him with some things on his website.  I agree that biochar is pyrolised biomass, not just charcoal. Commercial charcoal has wood still in it, so it doesn't sequester carbon the same way, and it also has lots of chemicals and oils that haven't been burned off yet.  IMHO biochar is used for agricultural purposes, not for reburning.  Although I think it's useful to crush it, I don't think that it has to be crushed to be biochar.  I run over it in large burlap bags, too.  However, if you don't add anything nutritious to charge it, it will decrease the productivity of the growing area for a year or two by sucking the nutrition out of it, so it's bad for agriculture.  Uninoculated, it is char in my book, and it doesn't become biochar until you put life-bio into it.  Most people who make biochar don't have a temperature gauge, so how would most people even know if it's biochar then? This is what makes me agree with Douglas that the guy is probably tooting his own horn. Some self marketing along with some useful ideas.

John S
PDX OR

It may be good to read this blog post: https://skillcult.com/blog/2012/05/18/some-citations-on-biochar-in-europe-and-america-in-the-19th-century

I haven’t read it in a while though… The author gathered together many sources and much information about historical use of charcoal for soil improvement, which tends to be thought of as a new thing even while it’s absolutely not. And it didn’t seem as if they had too much concern with the type of charcoal, how hot it was, etc., yet noticed the significant benefits and used it like mulch or even “manured” their fields with fine charcoal.

I think that people can be lax about specifics if they are placing biochar to sequester carbon only or for distant future fertility.  If you have a small garden and you are trying to help that piece of land become more fertile soon, you will make it less fertile for a few years, until the uninoculated char becomes biochar in your land.  I guess it depends upon your goals. I have a small piece of land, I'm already old, and I don't want my plants to become less productive for a few years.  Inoculating for a week is very easy, so I do it.  

The other concept was very intriguing.  There have been many cultures worldwide who have used something like biochar.   Bryant Redhawk detailed how many different cultures have used biochar like processes, in places as diverse as pre-Columbian America, Japan, and Africa, if I remember correctly. It makes sense that many indigenous people knew about this. They were very in touch with their land and the soil in it.  They could see the effect of fires on their land.   They were often able to move rather easily.  The Native Americans where I live burned the valley floor on purpose every year.  Many have speculated that they understood the effect that this would have on the soil.  They didn't have one million dollar houses and heavily built civilizations, so they could accept the positive benefits of regular fires on the soil, and adjust their housing to that.  

John S
PDX OR