Re: Embers from Three Stone as Biochar - Who has done this?

Hugh McLaughlin

Hello Many Different Groups, with many different priorities,

Ron has kicked several issues into my court to see if I will take the bait. I will to the extent of offering my thoughts, but I will decline the offer to convince the world I am right. You can lead a horse to water - the rest is up to the horse and whether it is sufficiently thirsty.

When it comes to biochar quality - it is easier to assess the material after it is made and cooled down than to predict/indemnify it based on how it was made or deserves to be good. It is like food: It is good unless it is bad for one of many reasons. The most basic criteria for biochar is the "Soap Test" - good char will not leave a black coating on the hands that will not be removed by cold water (mostly removed - it is a qualitative criteria and requires experience with other biochars. If soap is required to remove the biochar from one's hands, that is because of tars and the biochars is inferior and/or charcoal.

Good biochar does not have any significant burnt odor - or taste! - and wets out when dropped into water after being ground into a powder. Oh - if is friable - easily crushes into smaller particles and even collapses into a powder. Additional pluses, but not necessary, are a silvery reflection.

And, any contamination entering with the biomass will remain in the biochar - unless actual analytical measurements prove the contamination is not longer present. Hard to do, expensive, and not justified when one looks at the exhaustive list of clean biomass sources.

As for handles and letter combinations - I don't care and will not get into the fray.

My favorite disclaimer is BOHICA - which is obvious to those who have encountered it and better kept a secret for the others.

- Hugh

On Friday, April 2, 2021, 12:21:45 AM EDT, Ron Larson <rongretlarson@...> wrote:

Two lists  and cc Kevin and  Hugh Mclaughlin

See inserts below.

On Mar 31, 2021, at 8:37 PM, K McLean <kmclean56@...> wrote:

Stoves list, biochar list, cc Ron Larson

Have any of you actually used embers/char from an open-fire cookstove (eg 3-stone) or campfire as biochar (soil amendment)?  Did it work?  

African women can get plenty of char from three stone while cooking.  But will the char work as biochar?

Ron and I have been discussing this with others.  We all have ideas on why it should or should not work.  But we cannot find anyone who has actually tried it.
[RWL1:    I’m firmly in the ’should work’ camp.  I’ve been privileged to see more than Kevin's cites below and seen a lot of char produced with scientific knowledge of their measured chracteristics.  So I am pretty sure this char should have the large surface area we usually desire. - as in this famous graph from this early non-fee  Johannes Lehmann paper.

Hugh   what can you recommend for Kevin’s associates in rural African towns where this work is occurring?  (Hugh being the biochar expert I trust most on such measurements)

We want to train women on smallholder farms to collect, quench and crush embers and then charge the char and apply it to their fields.  I think this training can happen at scale with relatively little expense.  With hundreds of millions of families cooking over open fires, the potential is enormous.

[RWL2;  Kevin’s use of the word “charged” refers to urine.

Kevin has had great success using women’s auxiliaries in local churches to spread the word about adding rock beds under 3-stone fires to significantly improve stove efficiency.   Costs for adding one new rock bed user is pennies. The same likely here - with char removal. The difference from many such stove education programs is that this one will involve biochar.  We know that much more care has to be taken when the char is scheduled for the field rather than cooking a meal.

Using tongs to remove embers, women can make 300-800g of char daily.  Because they've reported that firewood usage does not increase, SNV did a simplified WBT and, counterintuitively, SNV found only an insignificant increase in fuel usage.

[RWL3:  I’ve. reviewed this SNV work (in Viet Nam) and have asked for the raw data as well as the finished reports.  

But I can believe the results. - because the embers that are being collected (by SNV and by women being paid for the char) had already mostly given up its hydrogen.  The fallen ember necessarily came from near the bottom of the fuel bed - where it was not contributing much to water boiling.

Kevin’s note is just the beginning of the study of what could be revolutionary for converting any 3 stone fire into a char producer.  Kevin and I have been discussing other features of a small modification of 3 stones that will only cost a few dollars and significantly improve efficiency.    I am quite sure we can go from a Tier zero performance to Tier 2 or 3 - with a lot of char.

I have Kevin’s permission to offer one possible name for his stove - a B-CHER. (“Cher” being pronounced as the French word for “Dear” - meaning premium or precious,).    The BC comes from being biochar itself shortened to BC or here B-C.    HER is short for “Hot Ember Removal”.   Only two syllables in B-CHER - as in “T-LUD.    Other thoughts?

Coming  are more details on how to make (locally) a Tier 2-3 stove for a few dollars.  I believe there are then billions who can find those few dollars if they are making char with little or no extra effort.  And they can first make char with no dollars invested.

This is why I am excited about Kevin’s newest work.

But will the char be effective?  Who has tried char made this way as biochar?

[RWL4:    I couldn’t recall any char or biochar papers along these  3-stone. lines.   But I told Kevin that I would look up some of the earliest biochar papers. (Before the name ‘biochar” was adopted).  They used char purchased along a rural road. Almost certainly this char was made in a mud covered mound - and therefor was  a low temperature char - much lower than char made in a. 3-stone fire.

A key way to think of Kevin’s approach is that all combustion (burning)) of wood starts with a pyrolysis phase.  The ‘HE” - hot ember will presumably have the low H2 we desire, simply because we know it went through a red phase - and. Kevin’s workers see no white ash.  Also I think virtually impossible for a “HE” hot ember to have broken off of the larger size pieces used in 3-stone fires, until it was indeed s usable char..

So I’m looking for Hugh M’s thoughts on HER and B-CHER.  

And others?


Kevin McLean, President

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