Biochar Workshop Part 1, How to Make Biochar


We’re working really hard to achieve four
goals at the same time. The first is to make the very best biochar. The second is to use as much of the process energy as possible. The third is to eliminate as many emissions as possible. The fourth is to make the whole process as profitable as possible for everyone. No matter what biomass we put in we could have carbon. This is how we really mean to take a bite out of our carbon footprint. Very glad to have you all here I’m Bob Wells from NewEngland Biochar in Massachusetts and representing Chargrow LLC in North Carolina. Our presentation today hopes to cover a lot of bases and we’ve
got a lot of good information from several sources. and then will also give you lots of
time to ask questions and try to fill in the blanks. Were excited that you’re all here
to experience this with us. Were certainly excited about biochar and what it can do for
farmers, gardeners and the whole world. We’re going to do this little bit backwards for
a couple reasons. I’m gonna start by showing you how to make some biochar in your own backyard if you want to. The reason I’m starting with this is because it takes a while and I want to make sure you to see the whole process and then we’ll go and talk about the details of biochar and start from the bottom and work our way up. To start with we’re going to make this
sort of biomass turn it into this sort of biochar with this simple 55 gallon drum and
a 30 gallon drum which we affectionately call the Tin Man. The way this works is we got a barrel inside of a barrel. The reason I Iike to show you this whole system is that it really represents everything that were doing on a much larger scale over there and
you can do it on a much smaller scale and once you get into playing with this kind of
stuff it’s really fun and you can come up with your own designs. There’s a million different
ways to do this. All you have to do is look on YouTube and you’ll see there’s dozens and
dozens of people trying different ways of doing it. There’s four rules that I’m always
preaching to everybody that I work with concerning biochar. Number one is we’re gonna try make
the very best biochar that we can make and this is good biochar. There’s a number ways
you can tell. If you look inside and there’s no brown inside. If you look outside there’s
no white ash on the outside. We’ve got really good pure char here and that’s not as easy
as it looks. I usually taste every batch to make sure it’s good no matter what it’s made
out of. Another good indicator that it’s good char is you can listen to it. If it clinics
when you drop it and move it. so you can hear the almost metallic or glassy like brittleness
of it. If you don’t hear that it’s probably not cooked enough. Good char taste like nothing
because like any good carbon filter it’s actually absorbing the things that you would be tasting
so it will actually take the taste out of things. It’ll take the smell out of things
it’ll take the toxins out of things just like a carbon filter it’s the same stuff its carbon.
Number one was to make the very best biochar. Number two, were going to use the energy that’s
available in the process because in the process of making biochar we are releasing a huge
amount of energy that’s coming out of that biomass that were making the biochar out of
so we want to make good use of that energy if at all possible and again my real job here
today is to inspire you to go and try it yourself and come up with new creative ways that you
can use it for your own applications. There’s lots of applications on farms and homes where
we need energy everybody needs energy we can offset the use of fossil fuels hopefully by
using that energy and some good useful way okay that’s number two. Number three, Were
going to avoid as much pollution of any kind that we can or doing any kind of environmental
damages as we can avoid that’s number three. The old way of making biochar if you’ve ever
seen the antique way they did it for many many centuries and are still doing it in some
countries and you’d get arrested if you tried to do it here is to make a big pile and get
it smoldering, they’d cover the pile with wet leaves and earth and so forth and let
it smolder in their and cook its way up through in the process of doing that your releasing
all the gases in the wood the gases i.e. smoke are going into the atmosphere making huge
amount of pollution that smoke is the same fuel that we’re gonna use in this process
to make it work. We’re gonna burn that smoke as much as we possibly can to avoid the pollution
and to use the energy at the same time so we’re killing two birds with one stone right
there and hopefully you’ll get an idea of how that’s working here. Number four we got
to make it profitable and I use the word profitable I used to I used to use the word we got a
make money with it and I’ve stretched a little bit by saying we got a make a profitable because
it doesn’t necessarily have to be money they were getting out of this but we got to see
that were getting something good out of it or we’re not gonna do it. So either the profit
is that we’re helping the environment or the profit is were making money or the profit
is your growing better food, more nutrient dense food whatever your profit is your helping
your community. There’s all kinds of profits that you can plug into number four but if
you don’t have all four going for you, chances are you’re not gonna keep doing it. Your not
going to feel the full benefit of what biochar can give you and so you’re probably not gonna
continue so that’s why I’m always trying to get people to see the whole picture. I was
already talking to somebody this morning about how they want see the whole picture here the
overall picture of why biochar is good and it’s it’s complicated for a very simple almost
purely carbon elemental stuff. The overall picture is actually quite complicated when
you start studying it and you have to get all the pieces to come together and that’s
what trying to do here and this is really one of the best examples in the world of that
happening there’s people all over the world trying to make those four rules work and most
of them don’t even realize that there’s four rules. They’re trying to make one of those
rules work and trying to do one of them, your gonna screw up on the other three. Trying
to do two of them you still do not get the full benefit, so the four rules we’re gonna
keep in mind all day. This is what we call our inner retort chamber and retort just means
to re-burn. Just some half-inch holes drilled in the bottom of this. This is a 30 gallon
drum, We’re gonna fill that with feedstock. There’s nothing on the bottom drilled out
on this one the outside drum. It’s sealed on the bottom so the inside drum is sitting
against that bottom. We’re going to fill inside drum feedstock. We just happen to have
really high class feedstock. This is coming out of furniture factories. It’s nice and
dry hardwood like the cadillac of feedstock. At home you probably have sticks and lumps
and that’ll work to but it probably won’t work with wood chips because if you fill that
would wood chips, they don’t breath and the gases will not escape well. It will insulate
itself and you’ll end up with a big brown spot in the middle the didn’t get cooked so
think of it as an oven. Now we put the top on their. It’s just the inside barrel full
now where the outside is not. Closed top only the inside barrel. Now we’re gonna fit wood
in here in the between spaces between these two barrels. Again were doing this with some
pretty high-class feedstock here Southern yellow pine in this case and were filling
in the annular space between the two. The drier the wood is that you’re using the better
off you’ll be in the end. We can fill in the spaces with this stuff. I’m usually using
round sticks at home, not these beautiful cutoffs. We don’t want to put any chemicals
into the process cause any heavy metals, copper, stuff out of paint that’s all you end up in
your biochar know the stuff were put in now is the fuel that’s gonna heat the inside chamber.
Now Abram’s gonna start a fire on top here. We’re always looking for waste products. We
don’t want to do this if we can help it in any way with new materials that we went out
and gathered just for this. There’s plenty of waste around that we can make biochar out
of and we can add that to our list of advantages. We’re eliminating waste which is a bigger
advantage then meets the eye at first cause if you study the carbon cycles of what’s going
on even with wood chips when you lay them on the ground whether it’s in the Forest or
in your backyard or in the county dump or whatever, this stuff is turning as it decays
back into CO2 as well as methane. Methane is a greenhouse gas 26 times worse than CO2
so any methane we can avoid is going to be better for the environment. By turning it
into biochar we’re gonna start sequestering that carbon that would be methane in the air
and we’ll go into that in more detail what we go and sit down. We’ll get this fire going
a little bit on top and what’s going to happen is it’s gonna burn down in between the cans
on the outside of the inside can and it’s going to burn down through. We’ve got primary
air holes down here so our air is going to get sucked up in here and keep this fire going
it’s interesting that were starting in on top and not on the bottom. If you start it
from the bottom it won’t work. It’s really kind of counter intuitive because we’ve all
been taught go underneath and start the fire from the bottom. In this case will start the
fire on the top. The fires going to slowly burn down because air is coming from down
here and up through the fire, as it does it’s going to cook the inside container, heating
the wood in that container which is sealed except for those holes on the bottom. The
gases that we cook out of that wood are all flammable gases. Anytime you see smoke like
right here your throwing fuel away. That smoke is fuel and if you can get the burn you’re
going to turn the fuel into energy. This is a simple way of doing that. If you can imagine
it starts to cook, makes the gas, the gasses have nowhere to go cause the top is sealed
it forces its way out of the holes in the bottom and comes out in between the cans and
ends up getting sucked up between the cans until it hits the coals burning the gas as
fuel, it burns the gas from the inside can in the wood on the outside of that can. Both
of which are going to heat the inside can and drive off more and more of that gas. Now
the key is, we don’t let it get much oxygen that’s always the key and pyrolysis is always
the key in making biochar, however you’re doing it is you either eliminate or at least
limit the amount of oxygen thats getting to the charge. In a retort system we’re pretty
much eliminating the oxygen. We’re gonna cook that wood on the inside using the wood on
the outside but not let any oxygen on the inside that way it won’t burn all the way
to ash it just drives off the gases but it doesn’t burn all the way if we get it wrong
and we got a hole in the topper or our seal is bad we’ll end up with a big can of white
ash on the bottom about that sick and we’ve wasted our time. So you little fire going
here and that fire were gonna push to the sides once it’s going. Normally a can of this
much material would make a lot of smoke but were gonna burn the smoke to the best of our
ability and once the gas starts coming out of the inside chamber in comes up into here
and meets the fire that’s moving down and burning it’s really fascinating because the
the gas will use the oxygen first long before the wood mover so you’ll have wood that will
stop burning right here and just burn gas until the inside is all out of gas and then
it’ll finish itself by burning the wood down. The beauty of this little design that I like
the best is that it’s very efficient labor wise once we get this lit and started, we
can put the top on it and walk away and it will do its own thing it’s completely self-regulating
you don’t have to stand there and wait for to finish and then put it out it puts itself
out. You can come back tomorrow morning and it’ll just be a beautiful can of biochar inside
and nothing on the outside. What forces the gases out is just its own pressure, it’s expanding
all the time. The first part of the process and it’s a multistage process is that your
driving the water out of the wood. If you can imagine a steam kettle, it’s pushing all
the time there’s a little bit of pressure and that drives it out of the holes so it’s
all a very natural process very low-pressure but there’s enough pressure because we didn’t
clamp the top on this can, if it we’re actually pressured up it would push the top up and
it would burn right here. It’s not gonna pop and explode or anything like that. know not
prop it up at all. if you do prop it up what can happen then at the end of the burn when
everything is still hot but all the coals are gone the oxygen can get back in his things
are going down and I will keep it lit and then everything inside will burn too. Again
this is a really neat system I think because you can light it and leave it as long as there’s
nothing burnable around it which is why were doing it in the driveway. Always one to be
safe I have one at home that I’ve run literally hundreds of times it’s a little bit bigger
than this I call it old faithful and I just come out in the morning and load her up. She’s
made out of stainless steel so she’s lasted a long time so I loader up like this light
it, cover it with a stack on it and go away and come back the next day take out my barrel
of char, dump it out reload the whole thing light it and go to work so each day I get
a load out of it. This process will probably take three or four hours so theoretically
you could get two loads out of it every day if you’re that ambitious at that point you
would want to dump the Char out and hose it down with water to make sure that it’s cooled
before you left it alone, putting it in a pile like this is actually little bit dangerous
i’m gonna warn you. Even when it’s nice and cool there’s still chemical processes going
on in there. Never assume that stuff is safe even when it’s cold you want to wet it down
as soon as possible to make sure it’s safe and spread it out if possible. Don’t leave
it in a big pile. Lots of safety issues but none of them are difficult you just have to
keep them in mind. Now these are secondary air holes we call them and what that will
do is if there’s any residual gas still coming through here and we haven’t got enough oxygen
in from down low
it will pull air in here and burn it before it gets out the chimney. You can hear the
fire now as soon as you put the chimney on it now you’ve got the thermal siphon going
and it’s pulling our primary air in here and our secondary air in here. We got lots of
fire going on right here it’s going to get hot real fast right here and we’ll end up,
even with a 4 foot stack you’ll end up seeing flame coming out of the top of this but notice
what you’re not seeing coming out the top of this is smoke. We’re gonna work real hard
to get the balance. I think of it like carburetor on an old-style engine getting the balance
between the fuel gas and the air mixture and the right amount of heat and you got a clean
burn you got efficiency. You can put a screen over the top. You’ve got a good draw on there
right now. If you want an even better draw you can use an insulated chimney and it goes
faster cause you’re not loosing any of the heat out the side of the chimney. At this
point we’ll start, at home i’ll put a big pan on here and start making spaghetti sauce
or something out of my rotten tomatoes or use and that’s a matter of using the energy.
We’ve already got number one, were making the best char we can. Number two we’re using
some of this energy if we want. Obviously we’re gonna throw a lot of it away we’re wasting
a lot of energy with this but it gets us started. Number three we’re not making a lot of pollution
here. If we had just burned that wood we’d be making a lot more smoke in an open pile
than we’re making right now or if we’d thrown it in a can with holes in it, we’d still be
making a lot more smoke than we are right now and that’s a matter of getting these holes
balanced off with the kind of wood you’re doing there’s a lot of tinkering to get it
this perfect. This will smoke at some point because it’ll get itself out of balance when
starts cooking that inside barrel and makes lots of smoke. It won’t be able to burn it
all and it will exhaust a little bit so just so you don’t hold me to that too tightly later
on you’ll see it happen and we can even adjust that by popping the top up a little give it
a little more air and it will clean it up. Just to give you an idea of how much the balance
counts for making smoke, we take this off and that’s not burning too dirty but it’s
cause we got this nice dry feedstock so doesn’t show as well but you can see the smoke and
the stuff coming off of it. Even if I put the clamp on the the top of this can it’s
not gonna seal it very well that clamp is made to be used cold with a rubber seal we’ve
peeled those rubber seals out because they make lots of nasty smoke obviously and so
it’s just sitting on their no chance of anything getting out of hand on this I’ve done it hundreds
of times. Once in a while you get a little woof if you get a burst of gas that mixes
and then ignites it will give you little woof. With our big reports we’ve done a lot of experimenting
with a lot of different materials and you can make biochar out of any biological material
pretty much anything that used to be alive you can turn it into biochar you can do with
bones you can do it with corn stover. I’ve done it with a pretty good feedstock is sunflower
stalks. Although the key is that if you’re looking for carbon by mass the mass that you’re
putting in is the mass you’re going to get out is directly proportional to the mass that
you’re gonna get out. Obviously corn stover I can pact one of our reports with corn stover
it’s only gonna weigh a couple hundred pounds you get about a third of that back as biochar.
So you’re only gonna end up with less than a 100 pounds where is if we Stoke out retort
with 2000 pounds which is about what we fit in of this hardwood we’re gonna get 500 to
600 pounds a biochar out of it so if you’re going by weight then that’s important if you’re
going by volume and you don’t care then use corn stover corncobs whatever sticks you got
laying around the yard you know that pile over there is very inviting to me most people
see it as a big pile of pine that needs to be gotten rid of. To me it looks like carbon
that needs to be sequestered. Alright so I’m gonna throw this back on and you can hear
it take off with the chimney. The chimney really helps pull the air in and will help
the process accelerate and we’ll watch that for the rest of the day or at least for another
four or five hours later on today we’ll open it up and I’ll show you what’s inside which
is essentially this. We made this in this so that’s what you’re gonna see but you can
also come over and get closer to it of your cold especially it’s gonna throw a lot of
heat and listen and watch it how much energy is coming out of the top of this thing all
day long that’s the energy were gonna try and catch. Right now there’s a big stream
of hot air coming out of this which hopefully is mostly CO2 and water vapor cause that’s
what were trying to get to is a clean burn where there’s no particulates and certainly
no carbon monoxide or other missions like that. Any other questions before we go inside.
If you got any sort of a business like a furniture company or anything, there is at least one
pallet recycler here there’s a phenomenal array of feed stock right. Yeah that’s a great
example of a place to get feedstock. Pallet wood is usually a hardwood usually pretty
dry the only thing I would say to be careful of with pallets is what was carried on them.
If it was chemicals that got spilled or if there were plastics or paint on them but otherwise
the only other thing is the nails that there put together with you want to be aware
of those. In our process you kind of got to get the nails out in order to keep it pure.
You can leave nails in and make char if it’s going into your garden or something like that.
Those nails will rust and break down but they can also puncture tires and feet and shoes
and it’s just another thing to be aware of but it is a great source of waste wood a real
good wood for charring makes really good char. That’s a six-inch stack on there, you can
use it. I use 8 inch insulated at home just cause that’s what I can find the dump and
then I just set it on top but this took me and the guys probably 20 minutes to make with
the two cans and no real special tools in fact if we have time and people want to see
it we’ll make another one while you watch just so you can see how it’s done it’s we’ve
done demonstrations up north where I make these with just a chisel and a hammer just
bang all the holes in that way. I mean Old Faithfull I discussed before is made out of
a stainless drum that came out of a candle factory they used to use it for melting wax
and it’s about 100 gallon drum so I can easily put a 55 inside of that and that works beautifully.
One of the downsides of this is because were heating that steel so hot in the inside with
these two drums made of regular carbon steel you’re gonna get about 10 runs before you
use up one or the other of those drums. It’ll just flake off until there’s nothing left
of that metal and you’ll have to get another drum. That gets into the profitability of
it. How much does it cost to make the char versus how much is the char worth when it’s
done. Obviously it’s gonna take a lot longer for the heat to get all the way through this
as it is to get only through this so there is there are limits both in small and large
you can’t go to small because we go to small what happens is they pack together and the
gases that are on the inside chamber won’t get out and they insulate the center of the
batch so if you put wood chips in that instead of blocks you’ll end up with a big lump in
the middle that isn’t chared at all. It’ll char about three or four or 5 inches maybe
and then it won’t work on the very center of it so that is an important thing. I love
to use sticks cause I’m clearing land so I’m using my slash and I’m running this while
I’m cutting trees down I’m packing it and running it on the side and it keeps me warm
in the winter cause I’m up in Massachusetts and it gets a little cold there sometimes.
Would it affect the performance of the chimney if the stack were of to one side to maximize
the heat surface for cooking? It might affect it a little bit because what you want is to
get that fire started all the way around the outside so it burns down evenly cause if it
burns down one side too fast it throws off the whole cycle but I’m sure it could be done,
I’m sure you could work that out and because I want you to use the heat. I love to see
the energy get used and I hate to see it thrown away like we’re doing now. Yeah two pots that
fit there right, or a big round pot with a hole in the middle that fits over the chimney
right? I’m not clear about the feed stock on the outside is that becoming biochar at
any point? No that’s just our starter material basically that’s to cook the inside if you
figure that into the yield it’s an important factor from that standpoint. By yield I mean
the ratio of what were putting in to what we’re getting out. Yes sir. What about the
ash that”s left around the exterior, can you talk about it’s use? Ash doesn’t bother me
I’ve got really acidic soil and I go around looking for ash where I can find it so the
little bit of ash that’s left from the wood burning on the outside. I’m usually just dumping
that right in with the biochar that I’m then mixing with my compost that I’m then putting
on my soil. Now if you’ve got really alkaline soil you might want to be more careful with
it and put it somewhere else but it’s it’s not in the same container so it’s easy to
do you can separate it out. The question is what’s the maximum cross-sectional area of
the feedstock that we could use in this and that’s a lot of that is dependent on the moisture
content the species whether it’s got bark on it. All of those things will have an effect
on it and you got a play with it. Making biochar is a craft. It really is a craft and you’ve
got to learn all of the pieces of that craft. Roughly probably three-inch would be the maximum
that you could ever get out of this now my old faithful at home also has a band of insulation
around the outside so I’m really focusing the heat in on that. It’s quite a bit bigger
than this so I’ve got to be able to get that heat penetration and I do that by putting
an alumina silicate blanket around the outside of it. Don’t try it with fiberglass it will
melt it. So again there’s lots of… I try to inspire you to try it and hopefully you’ll
have fun with it and not burn yourself or anybody else and not upset the neighbors with
lots of smoke and that’s the challenge. How do you process the chunks of char before you
put it in the soil? How do I process the the chunks of char? all that green and yellow
equipment that just came in off the truck is for doing that. At home I put it in the
driveway on a piece of plywood and I’d drive my tractor back and forth across it. At least
that’s how I used to do it before I ramped up my production and I crunch it up and then
I shovel it into my compost pit and let the compost work with it. What would happen if
you put it through a wood chipper? You would make cloud of black dust that would cover
the whole neighborhood. I speak from experience. So you could make these things where there’s
weather disasters, could you use them to burn the debris?There’s already people in FEMA
working on designs they can take with them again you got lots of in a hurricane disaster
or something like that, you’ve got wood all over the place you got your rid of and you
got energy needs everywhere you go so if you can convert that wood waste that’s all around
now you your win-win because you’re getting rid of the waste and you’re creating energy
that can be used hopefully at the same time. There’s also a lot of pollution in those areas
from the disasters, can the char actually help clean the area right where it was made?
Wow did you prepare these questions beforehand? This is a amazing. Yeah you certainly can,
again it’s a carbon filter they use it for remediation already. Activated carbon is used
commonly in remediation where there’s oil spill’s they use it for that. Where there’s
chemical spills, mercury all of those things it’ll soak it up. I n some cases there to
take it after it’s contaminated and deal with it but it will soak the stuff up. In other
cases you’re going to actually burn the stuff afterwards so you’d be using the energy at
least even though I hate to see char going up in a flame. So you’d use it to absorb stuff
and than burn it? Yeah and in other cases or to leave it in the ground because the biology
that comes into the biochar is going to keep working on things like fuel oil if you got
a fuel oil spill it’s the biology their using to change that oil into something that’s not
poisonous to humans so those are all key issues in the environmental aspects. Actually from
here you can see how nice and clean this is burning and it hasn’t started to make its
own gas yet but it will and it will start to really rip some more heat than that. Last
week the guys and I put together a little new style invention at least we thought it
was new until we went on the web and found other people already doing it but that’s what
lunch is being cooked on right over there. Woof! see I told you it can woof. This is
called a Rocket Avila Stove. It’s similar to what were doing here except that, that
has the ability to feed our starting fuel in the bottom like a rocket stoves if any
of you are familiar rocket stoves but it does have the inner chamber with holes in it so
the gases from the pyrolysis that’s happening inside can be forced into the center tube
and lit with air that’s coming in from the bottom and were cooking lunch on and making
biochar at the same time so this is a a new design that would just decided to try and
throw together for today’s demonstration and I’m sure if you try it you come up with other
ones and I really hope that if you do you’ll share them with me and other people so that
we can all is a community continue to perfect this kind of activity and teach it to the
kids and show them all the benefits and later on when we’re, after lunch and after that
cools down we’ll open it up and you can see the guts of it and how the flow works and
how you can put one together yourself if you want to. We were working on this design this
week out here. This particular one because yeah the wood were using is different than
what I use at home so you gotta change the inputs in order to get it to burn clean. One
of the things I’ve done on one of our later designs is to make those secondary holes variable
so I can adjust during the burn. So we can review a little bit on the can if anybody
wants to look at the flows in that tin man. In here you can see the inner chamber it really
happens in two phases the first phase we’re getting that inside can hot and then in the
second phase it makes the gas witch bubbles out the bottom and comes up into the fire
and ignites this would be the second phase and we get lots of fire from the gas once
the gas is gone and it runs out of gas that’s when the hard carbon is left behind so it’s
the fire then starts to go down and it finishes burning the stuff on the outside by the time
that gets down it’s really cooked that inner chamber of all of its gas so that’s a big
key to making biochar is to get all of all volatiles out of the feedstock that’s one
way of looking at it is that we’re taking a regular piece of wood and we’re going to
get the volatiles out of it and leave behind just the solid carbon so what are the volatiles?
It starts with water the first stage is we got is water out of it and water takes a lot
of energy to move which is a plus and minus depending on how you look at it.

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