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Recent Bio-char Study!  RSS feed

 
Roberto pokachinni
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Greg Martin
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Wow Roberto, thank you so much for posting this.  Very interesting read.  I'll be going over this article a few more times. 
 
Marco Banks
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For those who don't want to read the entire study (which is VERY impressive and well conducted):

Biochar added to a soilless potting mixture suppressed FORL crown and root rot of tomato and simultaneously improved tomato plant growth. By and large, biochar concentration and type had significant effects on plant performance and disease suppression, which increased with biochar concentration. There were no effects of biochar amendments on leaf nutrient status, plant tissue stability, photosynthetic pigmentation, or potting mixture water status. However, net photosynthesis rate, stomatal conductance, transpiration rate and electron transport rate increased following biochar amendments. Biochar amendments significantly shifted microbial community structure and functional potential of rhizosphere microbial community. Amendment with biochar also resulted in an increase in microbial taxon and functional diversity, microbial activities, and abundance of several groups closely related to biocontrol and plant growth promoting agents.



In short, in this comprehensive study, we have shown there is a strong link between biochar-induced changes in microbial community structure, taxon-functional diversity and microbial activity and resultant soilborne disease suppression and enhanced plant performance. These results put the rhizosphere microbiome in the center of the broad, multi-mechanism model that envisions the impact of biochar on plant performance and health to be a function of complex interactions between many physical, chemical and biological components of the soil-plant-pathogen system7,13. This concept, whereby the rhizosphere microbiome plays a central role in the biochar effect, is illustrated in Fig. 9. It conforms to the emerging view that there is a strong link between taxon and functional diversity in the rhizosphere microbiome and enhanced ecosystem functioning74,75,76, plant productivity 21,71 and plant resistance to diseases caused by soilborne pathogens19,20,72,73.
 
Roberto pokachinni
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I'm glad you liked it, Greg.

Thanks for giving us the succinct breakdown Marco!
 
Todd Parr
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I'm glad to see this.  I made another batch of charcoal this weekend.  As a batch finishes, I crush it and put it in my chicken coop.  When I clean the coop, it goes to a compost pile or directly onto a garden area.  Much of the research I've read about biochar shows little difference to the control, and that is a little disheartening.  I continued anyway, based on the fact that the charcoal should absorb odors, nitrogen and moisture from the chicken coop, so it wouldn't hurt.  It's nice to see that isn't the only benefit I'm getting.  Thanks for posting, and thanks Marco for the summary.
 
Marco Banks
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I'm skeptical of many things that are commonly promoted in permaculture circles.  Bio-char is one of those things.  (Don't get me going on the inflated claims of things like dynamic accumulators or the odd claims of biodynamics).  I've done a bit of personal experimentation with biochar in my own garden and haven't seen any sort of miraculous results.  Perhaps its because people tend to exaggerate the benefits of biochar in order to get people to adapt it.  When it's sold as a one-size-fits-all miracle cure to any garden problem, how can it end up doing anything OTHER than disappoint?

But this study seems totally legit and thoughtfully conducted.  The results of the study do not promise miracle cures or an end to all the worlds problems.  Their conclusions are modest and realistic: biochar is helpful in a limited sort of way.

The long-term benefits of using biochar certainly seem to make sense scientifically. 

1.  The biochar provides a "reef" for biologic life to attach to.  It adds to the "hosting" capacity of soil for bacterial and fungal life.

2.  The study shows that there is a clear difference in helping plants fight common pathogens that lead to plant unhealth.

3.  Biochar assists in both better soil drainage as well as soil water holding capacity (as all soil carbon tends to do).

4.  Biochar acts to catch nutrients as they move through the soil profile so they don't wash through so quickly.  Biochar isn't exactly a nutrient sponge per se, but rather, as soil biota colonize the tiny pieces of biochar, they are more able to "grab" the N, K, and P as it washes by. 
 
Roberto pokachinni
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So, what I like about the study is that it was very thorough and had a lot of controls.

What I don't like about it, was that the char was not amended/inoculated before being added to the soil, so it wasn't really biochar; it was char and was being fertilized via watering the soil from above (albeit a very efficient drip irrigation) with a designed fertilizer.

I'm curious what the results might have been had the char been inoculated before being added to the soil, and the soil simply watered in the biochar samples in the experiment with straight water; all others being fertilized via the watering method described.

 
nancy sutton
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Why do they call it 'biochar' when it is just charcoal?  ??  ?   Surely they understand the importance of exact terminology, being so scientific.
 
Greg Martin
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Charcoal is the catch all name for charred biomass.  You can make charcoal under many different conditions and you end up with charcoals with many differing properties.  If you want charcoal for the soil then there are a specific set of conditions you should strive to make it under.  These really do have large affects on the properties of the product.  When you make the charcoal under the conditions that give a product that is desirable for soil addition then you have a product we call Biochar.  I think a lot of people use that name willy nilly.
 
nancy sutton
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I wasn't clear... I've seen more than one 'scientific study' that used UN-innoculated charcoal and called it 'biochar'.  So the results were less than optimal, and they were  applied to biochar.  I'm surprised that 'scientists' don't seem to know the difference in the terms charcoal and biochar... like they've never heard of the history of terra preta... or the history of charcoal's known benefit in American and European agriculture in the 1800's and earlier (when manure application was common).  Like... duh!
 
Todd Parr
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I made the point on this forum quite some time ago that I use the term biochar for charcoal that has been inoculated, whether it be with urine, chicken manure, compost,...  An authority on the subject corrected that definition and said "Biochar is not called biochar because of adding biological elements. It is called biochar purely to differentiate it from charcoal, i.e it is charcoal for use as a soil improver, not for barbecuing sausages".  I still prefer my definition because the charcoal that you use as a soil improver is exactly the same charcoal as you use for barbeque, unless you inoculate it with something.  To each his own.  
 
John Weiland
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nancy sutton wrote:  I'm surprised that 'scientists' don't seem to know the difference in the terms charcoal and biochar...


Because as a group they are humans first and scientists second.  No different than MD's would differ across the map in terms of what might be called "healthy" and "unhealthy".  I can understand where "biochar" would have arisen to describe a 'concept',---the augmentation/cultivation of microbial communities using charcoal as a substrate.  But as the field picks up and maybe enjoys more in-depth investigation, it may come to pass where a short communication is issued down the road to separate the terminology distinguishing inoculated and uninoculated charcoal substrate in biochar studies.  At any rate, it makes sense that microbial communities would have evolved to take advantage of charred organic substrates that were formed after fires that swept across field and forest and subsequently supported new plant growth that participated in mutually beneficial interactions.
 
Roberto pokachinni
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What is Bio-Char?  There seems to be some debate on what is defined as bio-char.

My own take on the nomenclature debate is that there is a discrepancy that can be broken down as follows.

A) it was created using specific pyrolitic techniques/temperatures which deprive the desired biomass material of oxygen while releasing bio-gas and bio-oils, and this differs from charcoal which (for whatever reason) is simply wood that was insufficiently burned.

B) it was created by taking any charred biomass material regardless of combustion temperatures/techniques, and adding nutrients/inoculations.

C) it was created with specific pyrolitic techniques/temperatures and has had the nutrients/inoculations added to it.

It would be good to see a scientific comparison of the three techniques based on something measurable like cation exchange capacity.

While some believe that the temperature of the biomass as it is turning to char is important, others say that it is not that important, so long as char is produced and is then inoculated with nutrients.

I like the idea of C, since there is potential to harness the gas for other uses, while getting the gains of quality char and the inoculations.  Clearly ancient amazonian Terra Preta was not created using a syn gas generator, but may have been a lot more sophisticated and scientifically manufactured than some would leave us to believe: that these incredibly stable and productive soil system where built by uncivilized people by random chance. 

I like this very simple process which is what I built.  simple gasifying retort  It allows me to cook outdoors and get char made.

I also really like this video:


A recent permies thread involving the last video can be found Here

This is intriguing: pit biochar production for bulk production, but with limited applications for using the heat and none for using the exhausted gases.

Now that I have some welding training, I will likely build one of these: Wood Gasification Unit



 
Tyler Ludens
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Charcoal making is an old technology (4000 years old or so).  It isn't "random."

 
Todd Parr
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Roberto, I use the same method you do currently with the "barrel in a barrel" method, but it is so horribly inefficient (less so for you since you are using the heat to cook with) that I am going to try a new method this weekend.  I have an experimental thing I built when I was playing with the rocket stove idea.  It is basically just a 6" j-tube with a 55 gal drum around it that is insulated with rock wool.  I am going to use the small inner barrel from my other biochar process, put spacers to hold it up an inch or two and put it over the top of the j-tube "chimney".  Once I get the fire going, I will put another 55 gal barrel that is open on both ends on top of the first one and around the small barrel.  I should be able to get higher temps and use much less wood to cook the gas off the small barrel.

As far as nomenclature, I'm not sure I understand your A). In my mind, that describes making charcoal, at least commercially, and by most DIYers.  Even throwing wood in a pit to burn and covering it with dirt before it turns to ash is a "specific pyrolitic technique".  If by C) you mean using much higher temperatures to create the charcoal before inoculating it, I would agree that that is preferred because it makes "better" biochar, but not necessary, and may be out of the realm of possibility for many DIYers.  Therefore I use your B) as my definition.

Another area I would like to see studied would be geared toward finding the optimal amount of biochar added.
 
Roberto pokachinni
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Clearly ancient amazonian Terra Preta was not created using a syn gas generator, but may have been a lot more sophisticated and scientifically manufactured than some would leave us to believe: that these incredibly stable and productive soil system where built by uncivilized people by random chance. 
  I should have said, "than some would lead us to believe".

Tyler Ludens wrote:
Charcoal making is an old technology (4000 years old or so).  It isn't "random." 
  I agree.  I was speaking specifically of the anthropogenic soils known as Terra Preta, and that some people are not convinced that these soils were built specifically/purposefully rather than being, for instance, large waste middens which included char from home cooking fires which later became productive soils by more random biological than designed scientifically by a tribal horticulturalist. 
 
Roberto pokachinni
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Todd Parr wrote:
It is basically just a 6" j-tube with a 55 gal drum around it that is insulated with rock wool.  I am going to use the small inner barrel from my other biochar process, put spacers to hold it up an inch or two and put it over the top of the j-tube "chimney".  Once I get the fire going, I will put another 55 gal barrel that is open on both ends on top of the first one and around the small barrel.  I should be able to get higher temps and use much less wood to cook the gas off the small barrel. 
  Still sounds like an outdoor only system.  Interesting design idea, though.  I have been trying to wrap my brain around incorporating a retort into a rocket stove system, but I have never been able to find anybody who has come up with anything, and I haven't been able to figure out a way to do it myself.  I would love to have a RMH that has a retort in it that could be inside.  I like the possibilities of your design.  If you build this, please create a thread about it in this forum, as well as the Rocket Stove forum.
 
Todd Parr
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Yes, it's very much an outdoor-only design.  I'll try to get pictures this weekend.

I have no idea how a person could realistically create large amounts inside their house.  The video you posted of the guy making it in the wood stove is interesting and I love the idea, but it's fairly attention intensive and the amounts are pretty small unless you do it several times a day as he does.  A cool idea though.
 
Greg Martin
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Roberto, I do all my biocharring in the open pit method like Pacific Biochar used to do, only my pit is smaller and I think a bit more controlled.  It burns very cleanly and because it's a smaller system it's easier to do some cooking on or to boil down some maple syrup over.  I love making it this way...you basicly get to enjoy hanging out by a fire pit while making a large pile of Biochar. 

I highly suspect that this was the method used in the amazon, but who can say for sure.  My pure conjecture on that is that they may have made their Biochar in an open cooking pit, then added the food and buried it to slow cook in this earth oven.  Then when you remove the food you quench the Biochar if needed and shovel it out so that your pit is ready for the meal and the Biochar is available to be used in a latrine.  Again, pure conjecture, but it would make a lot of sense.
 
Roberto pokachinni
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your A). In my mind, that describes making charcoal, at least commercially, and by most DIYers.  Even throwing wood in a pit to burn and covering it with dirt before it turns to ash is a "specific pyrolitic technique".  If by C) you mean using much higher temperatures to create the charcoal before inoculating it, I would agree that that is preferred because it makes "better" biochar, but not necessary, and may be out of the realm of possibility for many DIYers.  Therefore I use your B) as my definition.
  You are probably right about my A); what I was meaning more was that people are saying that the char making temperature must be within certain parameters or it isn't bio-char; they are talking about resins and such that remain in the wood, while oils which go gaseous at these temperatures are burned off in the process.  I agree that this might be out of the realm of most DIY'ers but the simple retort does manage to do this, from my understanding.  B) is definitely a lot more of a loose definition, and definitely serves the purpose for the general definition as far as I'm concerned, though I tend to want to aim for the best possible product that I can create. 

I was just surprised that there was not a specific note in the study which described what bio-char is, or how what they were using should be defined, especially considering that it seems that they missed the mark by not inoculating the char prior to incorporating it into the soil with their process.

Another area I would like to see studied would be geared toward finding the optimal amount of biochar added.
  I think there are some basic ideas on that, but, I agree it would be nice to see some definitive studies.
 
Roberto pokachinni
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The video you posted of the guy making it in the wood stove is interesting and I love the idea, but it's fairly attention intensive and the amounts are pretty small unless you do it several times a day as he does.  A cool idea though.
  I agree. I really like the idea that the gases are being used to reduce his wood fuel consumption for heating.  Considering that he is getting bio-char while getting all of the regular benefits of the conventional wood stove, and reducing his fuel load, it might be worth the extra attention.   ??   
 
Greg Martin
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Roberto pokachinni wrote:
The video you posted of the guy making it in the wood stove is interesting and I love the idea, but it's fairly attention intensive and the amounts are pretty small unless you do it several times a day as he does.  A cool idea though.
  I agree. I really like the idea that the gases are being used to reduce his wood fuel consumption for heating.  Considering that he is getting bio-char while getting all of the regular benefits of the conventional wood stove, and reducing his fuel load, it might be worth the extra attention.   ??   


It takes very little attention really.  I do it every winter and it just feels great as you fill up a barrel.  Also it's handy to have fresh Biochar in the house to add to the compost bucket.
 
Greg Martin
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If you form your Biochar at the temperature where you see it just glowing red you should be in the "optimal" temperature range.  Very easy for a DIY Biochar maker to achieve.  Biochar made at lower temps doesn't last as long, Biochar made at higher temps don't fix as much carbon.
temperature.jpg
[Thumbnail for temperature.jpg]
 
Roberto pokachinni
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I do all my biocharring in the open pit method like Pacific Biochar used to do, only my pit is smaller and I think a bit more controlled.  It burns very cleanly and because it's a smaller system it's easier to do some cooking on or to boil down some maple syrup over.  I love making it this way...you basicly get to enjoy hanging out by a fire pit while making a large pile of Biochar.
  What is the basic diameter and depth of your pit?  Is it lined with stones?  
I highly suspect that this was the method used in the amazon, but who can say for sure.  My pure conjecture on that is that they may have made their Biochar in an open cooking pit, then added the food and buried it to slow cook in this earth oven.  Then when you remove the food you quench the Biochar if needed and shovel it out so that your pit is ready for the meal and the Biochar is available to be used in a latrine.  Again, pure conjecture, but it would make a lot of sense.
  Yes, it would make some sense, but as you say, pure conjecture.  We have no idea how it was made.  I'm of the opinion,extrapolating in a similar direction, considering the masses of immense jungle trees and the masses of green leaves that were available on clearing an area for building a village and garden (which may be slowly migrating through the jungle), I feel that it was likely a long trench fire with the excavated material nearby.  This makes more sense to me, especially when one considers that they were using limited stone tools to chop the wood as few times as necessary.  My guess is that they chose a spot where they wanted to create a garden bed, probably on the shady edge of the clearing, and dug the trench there.  I figure that they put whole logs in the trench and lit fires along it, and once the logs were involved in the flames to the desired amount, covered it with soil.  They probably added pockets of leaf wrapped food stuffs for a ceremonial feast which was attached to the whole "new village & garden" project.  I imagine that the next day some of the char was exposed and used as a latrine, and inoculated with some of the leaves and their other wastes before being slowly mixed with the soil that was in the trench, over time as more waste was created and as more perpetually encroaching jungle was slashed back.  
 
Greg Martin
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My pit is about 5' in diameter and maybe 1.5'deep with roughly 45 degree walls.  It is partially stone lined, though I'm using granite and it just breaks down from the heat over time.  If we had much basalt around here I'd use that instead as it should hold together better due to the lack of grain.  I get about 150 gallons per fire or so.  I've measured the volume reduction and it seems that I'm not loosing anything to ash formation.
 
Roberto pokachinni
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Thanks for your input, Greg, and thanks for posting that graph. Where did the graph come from?    What sort of container do you use inside your wood stove in the winter?
 
Roberto pokachinni
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What sort of wood (species) are you making your char out of?  Is it dried?  Is it small wood or large chunks?
my pit is smaller and I think a bit more controlled.
What controls do you suppose are benefiting your system when compared to the Pacific Bio-char system? 
I get about 150 gallons per fire or so.
Holy frijoles!
 
Greg Martin
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Roberto pokachinni wrote:Thanks for your input, Greg, and thanks for posting that graph. Where did the graph come from?    What sort of container do you use inside your wood stove in the winter?


Hi Roberto, I pulled that graph off of this website that pulled it from a 2007 Lehmann paper:  http://biochar.international/the-biochar-opportunity/biochar-production-and-by-products/
"The characteristics of feedstock and production parameters determine the physico-chemical properties and nutrient content of biochar. Based on surface area, pH, and cation exchange capacity (CEC), Lehmann (2007) proposed a temperature between 450-550oC to optimise the characteristics of biochar for use as soil amendment"

For my woodstove I use an old stainless steel pressure cooker that I found.  I use it with its strainer lid which has holes that look like a gas burner when it's pyrolyzing...kind of fun to watch.  I carefully quench it with water when it's completely done charring as it would otherwise let too much oxygen in if left alone for too long.  The warming pans in the video might be a better idea, but I'm happy making a gallon at a time with my cooker.
 
Greg Martin
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Roberto pokachinni wrote:What sort of wood (species) are you making your char out of?  Is it dried?  Is it small wood or large chunks?
my pit is smaller and I think a bit more controlled.
What controls do you suppose are benefiting your system when compared to the Pacific Bio-char system? 
I get about 150 gallons per fire or so.
Holy frijoles!


I dry all the wood I char as it burns more cleanly and the process seems to go better.  I like using the smaller diameter branches left over from cutting trees for firewood.  These are hardwood species.  But I also char a lot of softwood that I pick up along the side of the road from tree crew work.  The hardwood gets picked up for people's woodstoves, but the softwood is left to rot.  I figure that carbon would be back in the atmosphere within a few years unless I char it.  I cut this wood to about 2' lengths and split it because the full diameter is too large to work well in my sized pit...just takes too long to char all the way to the core.  I start with a cone of the branches and then start adding the larger split pieces, maintaining a cone geometry.  The idea is to maintain a flame cap by constantly adding the wood to the outside just where it's needed while the inside is converted to Biochar.  The outer wood layers burn off each other generating the pyrolysis gas that burns and consumes all the oxygen so none gets to the Biochar that has already formed and is in under the flame cap.  When the pit is full of Biochar I start adding the smaller branches again.  They maintain the temperature and the flame cap so that the last of the larger split pieces can finish up and break into chunks of Biochar.  After those last pieces are almost done I rake them to one side to finish up and I start quenching the pit with water from my hose.  When the last pieces are done I start dumping 5 gallon buckets of water into the pit to help quench the pit.  I fill those buckets while charring so they're ready to go.  That's not usually enough water and so I keep spraying for a while, then turn over shovels full of Biochar to make sure I have it all out....don't want to loose all that gorgeous Biochar to a hot core that reignites.  In the end I have had a nice time out by a camp fire and have cleared up brush, branches that fall from my trees and prunings from my forest garden.  Usually I've also had some smores.

The Pacific Biochar pit is much larger than my pit.  That's a big advantage as it gives larger production volumes and allows you to stay further back and heave in the wood, but it makes it harder to be precise with wood placement.  The pictures I've seen make it look like that tradeoff leads to a bit more smoke and perhaps a bit less control on the flame cap, but it really does seem like a nice system.  It's the one I modeled my approach off of.  I just didn't need that large a pit.  In fact, for demo purposes I'm going to start trying a smaller pit with just the branches so that it takes less time.  My 5' pit takes about 4 hours to produce that 150 gallons.  I enjoy that process very much....it's just too long for the demos. 

I think the larger the pit, the longer it will take, but the more Biochar you'll produce per hour.  It also means you can use larger diameter wood and therefore spend less time cutting and splitting...a further time saver.  Check out the system Dolf in Australia uses....it takes 12 hours to do a batch, but that's one serious batch!
 
Roberto pokachinni
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Thanks for your detailed descriptions, Greg  You are a champ!
 
Greg Martin
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Location: Maine, zone 5
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If you ever find yourself in Maine Roberto, drop me a line and we'll make a batch of Biochar together (although I'd recommend going to Hawaii to make a batch there with Josiah Hunt if you have a choice....Maine is great, but Hawaii...)
 
Roberto pokachinni
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Location: Fraser Headwaters, B.C., Zone3, Latitude 53N, Altitude 2750', Boreal/Temperate Rainforest-transition
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Thanks for the invite and ... Back at ya, Greg.   Never can tell what the universe has in store for a guy.   If a five years ago I was asked what I'd be doing now, I would never have guessed a railway welder.  I'm sure Hawaii would be great, but I have a hankering also to head out to New England and the Canadian Maritimes one day.   ... not in the foreseeable future though.  Too many projects and not enough time out from the day job to even get them done. 
 
nancy sutton
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Location: Federal Way, WA - Western Washington (Zone 8 - temperate maritime)
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Ditto Greg... thanks for all the detail! 
 
Greg Martin
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Felt bad about not posting pics....sorry
This one is an old pic of my first pit firing (pit is bigger and deeper now)...this is the start up.
start.jpg
[Thumbnail for start.jpg]
 
Greg Martin
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Here it is about mid way along....note how clean the burn is
middle.jpg
[Thumbnail for middle.jpg]
 
Greg Martin
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At the end you have a pit full of Biochar....I keep watering it until the pile isn't dry anymore....this one is still steaming hot...more water going in
quenching.jpg
[Thumbnail for quenching.jpg]
 
Greg Martin
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And then after it all cools down you get to have fun with all your shiny new Biochar!  (the mycorrhizae are going to love you...and your plants!)  Quite a few carts in that pit
end.jpg
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Greg Martin
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nancy sutton wrote:Ditto Greg... thanks for all the detail! 


You bet Nancy....if you need more just ask.  My devious intent is to make everyone fall in love with making Biochar from waste wood.
 
I like tacos! And this tiny ad:
Ernie and Erica Wisner's Rocket Mass Heater Everything Combo
https://permies.com/t/40993/digital-market/digital-market/Ernie-Erica-Wisner-Rocket-Mass
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