[Stoves] Hand-makng small roundish briquettes:

[Art Donnelly]

Hi Ron,

Saturday morning at Aprovecho the t*rdquettes still seemed to have some
moisture. So, I brought them home and let them dry in the sun until this
afternoon. (Mon. 29th)
I filled an 8" diameter combustion chamber on a "test-bed" TLUD, to 8" (
sorry no scales today). This is a N.D. stove. I used pine cones soaked in
alcohol as an tinder with dry twigs as kindling. I got a beautiful
smokeless start and a steady yellow orange flame for 30 minutes. I liked my
turn down with these.  I wet quenched the briquets as soon as the flame
went blue. There was little ash and the resulting carbonized
t*rdquettes(can you give us a pronunciation guide for that) held
together well and
were uniformly charred to the center.

I liked these much better than the round "green" briquettes with the center
hole or the "sticks". I also licked your complete lack of briquetting
equipment. You are a machine.

I have attached a zip file with photos.
my best,
Art D.



On Mon, Jul 29, 2013 at 11:24 AM,
<stoves-request at lists.bioenergylists.org>wrote:

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>
>    1. Re: Cajun Rocket Pot (Andreatta, Dale A.)
>    2. Re: Cajun Rocket Pot (Tom Miles)
>    3. Kirk Harris' new TLUD contributions (rongretlarson at comcast.net)
>    4. Re: Pot shells / Fin shells (Lanny Henson)
>    5. Re: Pot shells / Fin shells (Crispin Pemberton-Pigott)
>    6. Re: Pot shells / Fin shells (Lanny Henson)
>    7. Re: Pot shells / Fin shells (Crispin Pemberton-Pigott)
>    8. pellet gasifier (rice hull pellets) (Paul Olivier)
>    9. Vat Cooke / Pot shells / Fin shells (Lanny Henson)
>   10. Re: pellet gasifier (rice hull pellets) (Lanny Henson)
>   11. Re: pellet gasifier (rice hull pellets) (Paul Olivier)
>   12. pellets in an urban setting (Paul Olivier)
>   13. Re: Cajun Rocket Pot (Todd Albi)
>   14. Re: Cajun Rocket Pot (Jonathan P Gill)
>   15. Re: Hand-makng small roundish briquettes: (Richard Stanley)
>   16. Re: Hand-makng small roundish briquettes: (Richard Stanley)
>   17. Re: pellets in an urban setting (rongretlarson at comcast.net)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 28 Jul 2013 14:11:51 -0400
> From: "Andreatta, Dale A." <dandreatta at sealimited.com>
> To: "Discussion of biomass cooking stoves"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Cajun Rocket Pot
> Message-ID:
>
> <62BD23D01AD1464FAF784719D5E63693012506A5 at colexch02.sealimited.local>
> Content-Type: text/plain; charset="us-ascii"
>
> I like it!!!
>
>
>
> As some of you know, I spent a lot of time around 2007-2008 working on
> finned pots, and never really got them to work well.  I didn't try this
> type of "pin fin" design because I couldn't figure out how to make a
> prototype.
>
>
>
> With this pin fin design (that's what mechanical engineers call this
> shape of fin) you increase the heat transfer area, but unlike the fins I
> worked with, you don't significantly change the flow of the gas.  You
> get high convective heat transfer coefficients.  Hot gases impinging on
> a surface (hitting the surface from a perpendicular direction) usually
> gives better heat transfer than hot gases flowing parallel to a surface.
> The basic tests that have been done prove this, at least with industrial
> fuel flames.
>
>
>
> I expect that with a sooty flame, you could use a brush to scrape off
> most of the soot, and what you don't get this time you can get next
> time.  Thin layers of soot wouldn't have much effect.  Perhaps arranging
> the fins in rows rather than circular arrays would make them easier to
> clean quickly.
>
>
>
> I expect that emissions per unit of time will increase, since you are
> quenching the flame more quickly at the bottom of the pot and stopping
> the reactions that would otherwise burn up some of particles and CO.
> The effect might be small or large.  On the other hand, if the time to
> boil is greatly reduced, the total emissions might be a lot less.
>
>
>
> I expect that you could make a pot out of cast aluminum with the fins
> cast in place.  You could use tapered pins to save material and improve
> castability.  You could probably also use sophisticated welding
> techniques, as has been described, or possibly furnace brazing
> techniques.
>
>
>
> The material of the pot doesn't make much difference.  Since all metals
> are much better conductors of heat than gases, it doesn't matter whether
> the metal is much better at conducting (stainless steel) or much much
> better at conducting (aluminum).  It would mostly then be a cost and
> manufacturing issue.
>
>
>
> The fins must be bonded (welded, brazed, soldered, cast in place) to the
> pot itself, otherwise there is too much resistance to heat transfer
> across the interface.
>
>
>
> What to do next?  Where does one get one?  If I can get a sample I could
> test it out on a variety of stoves, rocket, charcoal, open fire,
> gasifier, LPG, fire-in-a-bucket, etc.  I could prepare a quick report by
> the next ETHOS time.  Or, someone who does experimental work full time,
> such as Apro or many other labs, could do a better job in less time.
> What I'm saying is that this is a very exciting development, that could
> make a huge difference in what we do.  We should pursue this quickly.
>
>
>
> Dale Andreatta, Ph.D., P.E.
>
>
>
>
>
>
>
> From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf
> Of Dean Still
> Sent: Sunday, July 28, 2013 11:36 AM
> To: Discussion of biomass cooking stoves
> Subject: Re: [Stoves] Cajun Rocket Pot/ capacitive discharge stud weldie
>
>
>
> Hi Lanny,
>
>
>
> We tested a couple of pots with fins but the space between the fins
> clogged up quickly with soot, a good insulator.
>
>
>
> Best,
>
>
>
> Dean
>
> On Sun, Jul 28, 2013 at 5:21 AM, Lanny Henson <lannych at bellsouth.net>
> wrote:
>
>
>
>         Lanny have you seen capacitive discharge stud welding?
>
>
> Yes I have a stud welder but I did not realize it would weld dissimilar
> metals especially aluminum to anything else.
>
> Stud welding is very finicky and will leave a blemish on the opposite
> side of thin metal.
>
> When a stud weld fails you have to grind the surface to clean it up
> before rewelding.. How are you going to do that if it is between the
> other studs?
>
> Attaching studs, fins or anything to a pot is going to be problematic,
> but attaching something to the pot holder may be practical. The heat
> transfer may not be as good as having something attached to the pot but
> it could possibly improve the heat transfer.
>
> Lanny Henson
>
> ----- Original Message ----- From: <ajheggie at gmail.com>
> To: "Discussion of biomass cooking stoves"
> <stoves at lists.bioenergylists.org>
> Sent: Sunday, July 28, 2013 5:23 AM
> Subject: Re: [Stoves] Cajun Rocket Pot
>
>
>
> [Default] On Sat, 27 Jul 2013 20:48:02 -0400,"Lanny Henson"
> <lannych at bellsouth.net> wrote:
>
> I like creative people and take no pleasure criticizing their work but
> it is going to be too expensive and difficult to make with all the pegs.
>
>
> Lanny have you seen capacitive discharge stud welding? This would
> allow welding of dissimilar metals to the pot in any pattern. I have
> no idea of costs.
>
> Have you done heat transfer tests with your 4mm aluminium pot compared
> with the thinner stainless one? Stainless is a notoriously poor
> conductor of heat and theoretically would need to be just under a
> tenth of the thickness of aluminium for the same conductivity, but I
> do use stainless pots at home.
>
> Finally can you explain the difference between a vat and a pot?
>
> Paul I do consider this to be important because biomass stoves have an
> inherent problem with heat transfer compared with natural gas or LPG
> so improvements in heat exchange will have high benefits.
>
> AJH
>
>
>
>
> _______________________________________________
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>
> to Send a Message to the list, use the email address
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>
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>
> ------------------------------
>
> Message: 2
> Date: Sun, 28 Jul 2013 11:26:31 -0700
> From: "Tom Miles" <tmiles at trmiles.com>
> To: "'Discussion of biomass cooking stoves'"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Cajun Rocket Pot
> Message-ID: <000601ce8bbf$fbdf68a0$f39e39e0$@trmiles.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Is a TLUD likely to have less soot buildup on fins?
>
>
>
> Tom
>
>
>
> From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of
> Andreatta, Dale A.
> Sent: Sunday, July 28, 2013 11:12 AM
> To: Discussion of biomass cooking stoves
> Subject: Re: [Stoves] Cajun Rocket Pot
>
>
>
> I like it!!!
>
>
>
> As some of you know, I spent a lot of time around 2007-2008 working on
> finned pots, and never really got them to work well.  I didn't try this
> type
> of "pin fin" design because I couldn't figure out how to make a prototype.
>
>
>
> With this pin fin design (that's what mechanical engineers call this shape
> of fin) you increase the heat transfer area, but unlike the fins I worked
> with, you don't significantly change the flow of the gas.  You get high
> convective heat transfer coefficients.  Hot gases impinging on a surface
> (hitting the surface from a perpendicular direction) usually gives better
> heat transfer than hot gases flowing parallel to a surface.  The basic
> tests
> that have been done prove this, at least with industrial fuel flames.
>
>
>
> I expect that with a sooty flame, you could use a brush to scrape off most
> of the soot, and what you don't get this time you can get next time.  Thin
> layers of soot wouldn't have much effect.  Perhaps arranging the fins in
> rows rather than circular arrays would make them easier to clean quickly.
>
>
>
> I expect that emissions per unit of time will increase, since you are
> quenching the flame more quickly at the bottom of the pot and stopping the
> reactions that would otherwise burn up some of particles and CO.  The
> effect
> might be small or large.  On the other hand, if the time to boil is greatly
> reduced, the total emissions might be a lot less.
>
>
>
> I expect that you could make a pot out of cast aluminum with the fins cast
> in place.  You could use tapered pins to save material and improve
> castability.  You could probably also use sophisticated welding techniques,
> as has been described, or possibly furnace brazing techniques.
>
>
>
> The material of the pot doesn't make much difference.  Since all metals are
> much better conductors of heat than gases, it doesn't matter whether the
> metal is much better at conducting (stainless steel) or much much better at
> conducting (aluminum).  It would mostly then be a cost and manufacturing
> issue.
>
>
>
> The fins must be bonded (welded, brazed, soldered, cast in place) to the
> pot
> itself, otherwise there is too much resistance to heat transfer across the
> interface.
>
>
>
> What to do next?  Where does one get one?  If I can get a sample I could
> test it out on a variety of stoves, rocket, charcoal, open fire, gasifier,
> LPG, fire-in-a-bucket, etc.  I could prepare a quick report by the next
> ETHOS time.  Or, someone who does experimental work full time, such as Apro
> or many other labs, could do a better job in less time.  What I'm saying is
> that this is a very exciting development, that could make a huge difference
> in what we do.  We should pursue this quickly.
>
>
>
> Dale Andreatta, Ph.D., P.E.
>
>
>
>
>
>
>
> From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of
> Dean Still
> Sent: Sunday, July 28, 2013 11:36 AM
> To: Discussion of biomass cooking stoves
> Subject: Re: [Stoves] Cajun Rocket Pot/ capacitive discharge stud weldie
>
>
>
> Hi Lanny,
>
>
>
> We tested a couple of pots with fins but the space between the fins clogged
> up quickly with soot, a good insulator.
>
>
>
> Best,
>
>
>
> Dean
>
> On Sun, Jul 28, 2013 at 5:21 AM, Lanny Henson <lannych at bellsouth.net>
> wrote:
>
>
>
> Lanny have you seen capacitive discharge stud welding?
>
>
> Yes I have a stud welder but I did not realize it would weld dissimilar
> metals especially aluminum to anything else.
>
> Stud welding is very finicky and will leave a blemish on the opposite side
> of thin metal.
>
> When a stud weld fails you have to grind the surface to clean it up before
> rewelding.. How are you going to do that if it is between the other studs?
>
> Attaching studs, fins or anything to a pot is going to be problematic, but
> attaching something to the pot holder may be practical. The heat transfer
> may not be as good as having something attached to the pot but it could
> possibly improve the heat transfer.
>
> Lanny Henson
>
> ----- Original Message ----- From: <ajheggie at gmail.com>
> To: "Discussion of biomass cooking stoves" <
> stoves at lists.bioenergylists.org>
> Sent: Sunday, July 28, 2013 5:23 AM
> Subject: Re: [Stoves] Cajun Rocket Pot
>
> [Default] On Sat, 27 Jul 2013 20:48:02 -0400,"Lanny Henson"
> <lannych at bellsouth.net> wrote:
>
> I like creative people and take no pleasure criticizing their work but it
> is
> going to be too expensive and difficult to make with all the pegs.
>
>
> Lanny have you seen capacitive discharge stud welding? This would
> allow welding of dissimilar metals to the pot in any pattern. I have
> no idea of costs.
>
> Have you done heat transfer tests with your 4mm aluminium pot compared
> with the thinner stainless one? Stainless is a notoriously poor
> conductor of heat and theoretically would need to be just under a
> tenth of the thickness of aluminium for the same conductivity, but I
> do use stainless pots at home.
>
> Finally can you explain the difference between a vat and a pot?
>
> Paul I do consider this to be important because biomass stoves have an
> inherent problem with heat transfer compared with natural gas or LPG
> so improvements in heat exchange will have high benefits.
>
> AJH
>
>
>
>
> _______________________________________________
> Stoves mailing list
>
> to Send a Message to the list, use the email address
> stoves at lists.bioenergylists.org
>
> to UNSUBSCRIBE or Change your List Settings use the web page
>
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists
> .org
>
> for more Biomass Cooking Stoves,  News and Information see our web site:
> http://stoves.bioenergylists.org/
>
>
>
> -------------- next part --------------
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> >
>
> ------------------------------
>
> Message: 3
> Date: Sun, 28 Jul 2013 18:56:32 +0000 (UTC)
> From: rongretlarson at comcast.net
> To: Discussion of biomass <stoves at lists.bioenergylists.org>
> Cc: kgharris at sonic.net
> Subject: [Stoves] Kirk Harris' new TLUD contributions
> Message-ID:
>         <
> 490854862.1605379.1375037792893.JavaMail.root at sz0133a.emeryville.ca.mail.comcast.net
> >
>
> Content-Type: text/plain; charset="utf-8"
>
> List:
>
> In my last message: I said: " I watched the testing of an interesting
> stove designed by Kirk Harris (from La Rosa (?) CA. This was much larger
> version of a camping stove he brought. Good results on abbreviated testing.
> I'll write a separate report on this design as it had several features I
> have not seen elsewhere. "
>
> #1 was his means of controlling primary air: a paper clip of the large
> spring type attached to a circumferential band near the bottom. Had a
> single large "square" hole in the band for his camping stove (that allowed
> for adding fuel in a rocket manner, if needed). In the larger, impromptu
> verson he had only three equally spaced primary air holes. It seemed very
> easy to squeeze the paper clip to open the strap enough to rotate it for
> changing primary air. I am not sure how the strap was attached to the clip
> - maybe just two right angle bends in the loop ends.
>
> #2 was his use of "rock wool" for insulation. This prevented use of the
> gap between inner and outer cylinders for preheating secondary air, but he
> believes the tradeoff favors the added insulation. Only TLUD I have seen
> with this approach. Should be possible to prove one way or another with
> some modeling and or testng.. He still has some secondary air preheating as
> the secondary enters the combustion region. I heard one stove expert talk
> aganst this idea - so it needs more trials.
>
> #3 was use of swirl achieved by the entry angle of the secondary air. Many
> TLUDs with this swirl, but not at this stove camp.
>
> #4 was use of a rockwool (?) "stove rope" for sealing the top surface.
> Like #2, this was from a "Bucks" stove store.
>
> #5 was use of cans mostly throughout (had a small can to get extra draft)
> but used a "coil" of stainless steel (not a tin can) for the innermost
> surface of the camping stove to have better lifetime. Not sure on the
> larger unit, where everything was scrounged from Aprovecho stock.
>
> #6. As noted in #1, he could add fuel from the bottom with the camp stove.
> Not many (if any) TLUDs doing this. Reason in part that camping stoves
> needn't save char .
>
> $7 This Is the big one:- I have never seen in any other TLUD. Kirk had a
> third set of air holes that he called "intermediate" - that all pointed (by
> the bending of the slits in the stainless) downward. They were located
> slightly below the secondary air holes of #3. They were designed to burn up
> the char - not what I want for TLUDs, but quite appropriate for camping
> stoves.
> In most TLUDs that burn the char, the primary air supply is cranked wide
> open to prevent smoking; the problem is the heat release is far from the
> pot.. KirK does the opposite, mostly closing the (former) primary air
> holes. He finds a bright flame from the top combustion of the produced char
> .
> In the single run I saw, there was very little char left.
> We agreed that the TLUD-world needs a better handle on pressure
> differences within any TLUD .
>
> Other - Kirk showed me a 2-page writeup, with some of the above. All in
> all, Kirk has thought a lot of this through very well - for those who want
> little char. There are still several lessons for those of us who want the
> cahr.
>
> Ron
> -------------- next part --------------
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> >
>
> ------------------------------
>
> Message: 4
> Date: Sun, 28 Jul 2013 15:36:33 -0400
> From: "Lanny Henson" <lannych at bellsouth.net>
> To: "Discussion of biomass cooking stoves"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Pot shells / Fin shells
> Message-ID: <7EDB10E567A54294AFEF49E9ECAA8E09 at HP>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Well I had 186 LB of water and rice, the rice was 50 lb.
>
> Rice has a specific heat capacity of about .33 which is about the same as
> 16.5 of water so deduct 33.5 from 186 for a mass of about 152.5 lb water
> equivalent.
>
> I started with 15 LB. of wood and had 2.95 LB. left over = 12.05 LB. of
> wood used, and there was 1.5 LB. of charcoal left.
>
> The simmer time was about 30 min.
>
> The wrapper is 60" x and the vat is 48" long . I estimate the water was
> contacting about 36" of the 60" wrapper so the contact area was about 12
> sq. ft.
>
> Does that give you the numbers you need?
>
> Lanny
>
>   ----- Original Message -----
>   From: Crispin Pemberton-Pigott
>   To: 'Discussion of biomass cooking stoves'
>   Sent: Sunday, July 28, 2013 1:39 PM
>   Subject: Re: [Stoves] Pot shells / Fin shells
>
>
>   Dear Lanny
>
>
>
>   I wonder if you can help me out with more numbers. The comparison
> between a trough with ends and a pot is interesting.
>
>
>
>   Can you provide some water boiling volumes (initial) and mass of fuel
> burned? To check heat transfer efficiency the char mass will be needed. To
> check the system efficiency (fuel efficiency) the char should be ignored in
> most cases. What I would like to do is calculate the two and see if the
> surface area of the pot and vat are important considerations. They should
> be, but as I often say, never assume anything.
>
>
>
>   Best to check.
>
>
>
>   The effective heating area of the vat might be the sheet length x
> Sin(45) x Sheet width, or it may be sheet length x width. If the heat
> transfer efficiency per sq cm is the same, then the matter will soon be
> settled with a calculator.
>
>
>
>   Thanks
>   Crispin
>
>
>
>
>
>   From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf
> Of Lanny Henson
>   Sent: Monday, July 29, 2013 12:13 AM
>   To: Discussion of biomass cooking stoves
>   Subject: [Stoves] Pot shells / Fin shells
>
>
>
>   Fins/ pegs/ pot shells/ rocket pots.
>
>   If you are going to use fins they should be attached to a pot skirt that
> fits snug and stays on the pot until it needs to be cleaned. This keeps the
> soot if any contained and away from the cook.
>
>   Instead of a fin shell I am now using a "pot shell" that totally
> encloses the pot. The pot shell has a top tray that can be easily slid back
> for easy access to the pot. This is actually easier that removing a lid and
> another benefit with total enclosure is the pot is heated from the top as
> well as the sides and bottom.
>
>   The top tray can also dry wood and warm food items.
>
>   Another benefit of the pot shell is that it makes cooking in the rain
> possible.
>
>   The construction is very simple and it can be built from most any
> material that is non combustible.
>
>   A section of drum fits over a 40 qt sauce pot or a 60 qt stock pot. The
> pot handles may have to be bent in a little or the pot shell can be
> slightly oval to fit over the handles.
>
>   A pot shell requires a flat top stove body or a burner under a flat
> surface.
>
>   I believe the pot shell is the biggest bang for the buck to improve a
> stoves performance. They are cheep and easy to build. They add draft
> without allowing too much, they capture the heat, and allow cooking outdoor
> in the rain.
>
>   If the pot shell design helps your stove, run with it, and that goes for
> everyone.
>
>   I will have a video later today showing its use
>
>   Lanny
>
>
>
>
>
>
> ------------------------------------------------------------------------------
>
>
>   _______________________________________________
>   Stoves mailing list
>
>   to Send a Message to the list, use the email address
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>   http://stoves.bioenergylists.org/
>
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>
> ------------------------------
>
> Message: 5
> Date: Sun, 28 Jul 2013 17:14:38 -0400
> From: "Crispin Pemberton-Pigott" <crispinpigott at gmail.com>
> To: "'Discussion of biomass cooking stoves'"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Pot shells / Fin shells
> Message-ID: <00dd01ce8bd7$7876bc80$69643580$@gmail.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Dear Lanny
>
>
>
> The problem is the missing figure is the mass of fuel when the pot as
> boiled
> so I can't get an efficiency without making some (big) guesses.
>
>
>
> If the energy needed to simmer the rice for 30 minutes is 20% of the
> boiling
> energy, the system efficiency (which is the analogy of fuel efficiency) is
> 34%, conditioned on the following:
>
>
>
> If the charcoal remaining is useable in the next fire, it can be treated as
> 'unused fuel'. If you want an accurate figure, you would have to use this
> duel in a new fire and get the performance so that the amount of char
> remaining is the same as what you put in during that burn.
>
>
>
> The 34% figure assumes the char is not burnable in the next fire.
>
>
>
> If it is (all of it) the system efficiency is 51% based on the simmering
> assumption.
>
>
>
> It should be remembered that the thermal efficiency should consider the
> thermal mass of the pot (mass x specific x change in temperature. If it
> does, the reported figure will be higher.
>
>
>
> Regards
>
> Crispin
>
>
>
>
>
> From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of
> Lanny Henson
> Sent: Sunday, July 28, 2013 3:37 PM
> To: Discussion of biomass cooking stoves
> Subject: Re: [Stoves] Pot shells / Fin shells
>
>
>
> Well I had 186 LB of water and rice, the rice was 50 lb.
>
> Rice has a specific heat capacity of about .33 which is about the same as
> 16.5 of water so deduct 33.5 from 186 for a mass of about 152.5 lb water
> equivalent.
>
> I started with 15 LB. of wood and had 2.95 LB. left over = 12.05 LB. of
> wood
> used, and there was 1.5 LB. of charcoal left.
>
> The simmer time was about 30 min.
>
> The wrapper is 60" x and the vat is 48" long . I estimate the water was
> contacting about 36" of the 60" wrapper so the contact area was about 12
> sq.
> ft.
>
> Does that give you the numbers you need?
>
> Lanny
>
> -------------- next part --------------
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>
> ------------------------------
>
> Message: 6
> Date: Sun, 28 Jul 2013 18:42:47 -0400
> From: "Lanny Henson" <lannych at bellsouth.net>
> To: "Discussion of biomass cooking stoves"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Pot shells / Fin shells
> Message-ID: <03F43E7BE0BE4ACABFB8421E6BC8A70E at HP>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Crispin,
> I do not have that information. I did that 3 years ago.
> Also I did not use my best burner.
> I need to get back to that design it has potential.
> Lanny
>   ----- Original Message -----
>   From: Crispin Pemberton-Pigott
>   To: 'Discussion of biomass cooking stoves'
>   Sent: Sunday, July 28, 2013 5:14 PM
>   Subject: Re: [Stoves] Pot shells / Fin shells
>
>
>   Dear Lanny
>
>
>
>   The problem is the missing figure is the mass of fuel when the pot as
> boiled so I can't get an efficiency without making some (big) guesses.
>
>
>
>   If the energy needed to simmer the rice for 30 minutes is 20% of the
> boiling energy, the system efficiency (which is the analogy of fuel
> efficiency) is 34%, conditioned on the following:
>
>
>
>   If the charcoal remaining is useable in the next fire, it can be treated
> as 'unused fuel'. If you want an accurate figure, you would have to use
> this duel in a new fire and get the performance so that the amount of char
> remaining is the same as what you put in during that burn.
>
>
>
>   The 34% figure assumes the char is not burnable in the next fire.
>
>
>
>   If it is (all of it) the system efficiency is 51% based on the simmering
> assumption.
>
>
>
>   It should be remembered that the thermal efficiency should consider the
> thermal mass of the pot (mass x specific x change in temperature. If it
> does, the reported figure will be higher.
>
>
>
>   Regards
>
>   Crispin
>
>
>
>
>
>   From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf
> Of Lanny Henson
>   Sent: Sunday, July 28, 2013 3:37 PM
>   To: Discussion of biomass cooking stoves
>   Subject: Re: [Stoves] Pot shells / Fin shells
>
>
>
>   Well I had 186 LB of water and rice, the rice was 50 lb.
>
>   Rice has a specific heat capacity of about .33 which is about the same
> as 16.5 of water so deduct 33.5 from 186 for a mass of about 152.5 lb water
> equivalent.
>
>   I started with 15 LB. of wood and had 2.95 LB. left over = 12.05 LB. of
> wood used, and there was 1.5 LB. of charcoal left.
>
>   The simmer time was about 30 min.
>
>   The wrapper is 60" x and the vat is 48" long . I estimate the water was
> contacting about 36" of the 60" wrapper so the contact area was about 12
> sq. ft.
>
>   Does that give you the numbers you need?
>
>   Lanny
>
>
>
>
> ------------------------------------------------------------------------------
>
>
>   _______________________________________________
>   Stoves mailing list
>
>   to Send a Message to the list, use the email address
>   stoves at lists.bioenergylists.org
>
>   to UNSUBSCRIBE or Change your List Settings use the web page
>
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>
>   for more Biomass Cooking Stoves,  News and Information see our web site:
>   http://stoves.bioenergylists.org/
>
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>
> ------------------------------
>
> Message: 7
> Date: Sun, 28 Jul 2013 22:56:40 +0000
> From: "Crispin Pemberton-Pigott" <crispinpigott at gmail.com>
> To: "Stoves" <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Pot shells / Fin shells
> Message-ID:
>
> <324725998-1375052206-cardhu_decombobulator_blackberry.rim.net-1418506894- at b27.c10.bise6.blackberry
> >
>
> Content-Type: text/plain
>
> I would be interested in reports on it. The char production was a quite
> high so you might work on that aspect. In a fuel efficiency calculation
> char is a 'mechanical loss'.
>
> I have been having discussions on the various 'efficiencies' in Mongolia
> and China in the last couple weeks. We need to nail these down with
> validated theoretical explanations so different test results can be
> translated in parallel.
>
> Regards
> Crispin
> From BB9900
>
> -----Original Message-----
> From: "Lanny Henson" <lannych at bellsouth.net>
> Sender: "Stoves" <stoves-bounces at lists.bioenergylists.org>
> Date: Sun, 28 Jul 2013 18:42:47
> To: Discussion of biomass cooking stoves<stoves at lists.bioenergylists.org>
> Reply-To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Pot shells / Fin shells
>
> _______________________________________________
> Stoves mailing list
>
> to Send a Message to the list, use the email address
> stoves at lists.bioenergylists.org
>
> to UNSUBSCRIBE or Change your List Settings use the web page
>
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>
> for more Biomass Cooking Stoves,  News and Information see our web site:
> http://stoves.bioenergylists.org/
>
>
>
> ------------------------------
>
> Message: 8
> Date: Mon, 29 Jul 2013 06:06:55 +0700
> From: Paul Olivier <paul.olivier at esrla.com>
> To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: [Stoves] pellet gasifier (rice hull pellets)
> Message-ID:
>         <CAOreFvaECS=1nKusZPAm4KU4_EyxoGFHBZaXYetzF=
> 11oUL84A at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> In a more user-friendly format:
>
> http://www.youtube.com/watch?v=Ss9lRB4SpOk
>
> http://www.youtube.com/watch?v=84qDsbBO9p8
>
> Thanks.
> Paul Olivier
>
> --
> Paul A. Olivier PhD
> 26/5 Phu Dong Thien Vuong
> Dalat
> Vietnam
>
> Louisiana telephone: 1-337-447-4124 (rings Vietnam)
> Mobile: 090-694-1573 (in Vietnam)
> Skype address: Xpolivier
> http://www.esrla.com/
> -------------- next part --------------
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>
> ------------------------------
>
> Message: 9
> Date: Sun, 28 Jul 2013 20:11:23 -0400
> From: "Lanny Henson" <lannych at bellsouth.net>
> To: <crispinpigott at gmail.com>, "Discussion of biomass cooking stoves"
>         <stoves at lists.bioenergylists.org>
> Subject: [Stoves] Vat Cooke / Pot shells / Fin shells
> Message-ID: <052F4A0E2FB74F499FF59D9F6BB8D6DE at HP>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>         reply-type=original
>
> Crispin,
> Were you able to view the video?
> http://www.youtube.com/watch?v=ntaqwZtq30g
> The left over charcoal had some nice large very usable pieces left over to
> have come from a cooking stove. I consider this a credit not a loss.
> My new TLC  burner "top lit Combustor" does consume more of the charcoal.
> The new burner is scalable so I will us it in the next vat cooker
> prototype.
> Here is the old burner I used. The roaring sound is from the natural draft
> mixing in the burner not from a fan or the wind.
> http://www.youtube.com/watch?v=tJvnJEhHAXY
> Lanny
>
>
>
> ----- Original Message -----
> From: "Crispin Pemberton-Pigott" <crispinpigott at gmail.com>
> To: "Stoves" <stoves at lists.bioenergylists.org>
> Sent: Sunday, July 28, 2013 6:56 PM
> Subject: Re: [Stoves] Pot shells / Fin shells
>
>
> >I would be interested in reports on it. The char production was a quite
> >high so you might work on that aspect. In a fuel efficiency calculation
> >char is a 'mechanical loss'.
> >
> > I have been having discussions on the various 'efficiencies' in Mongolia
> > and China in the last couple weeks. We need to nail these down with
> > validated theoretical explanations so different test results can be
> > translated in parallel.
> >
> > Regards
> > Crispin
> > From BB9900
> >
> > -----Original Message-----
> > From: "Lanny Henson" <lannych at bellsouth.net>
> > Sender: "Stoves" <stoves-bounces at lists.bioenergylists.org>
> > Date: Sun, 28 Jul 2013 18:42:47
> > To: Discussion of biomass cooking stoves<stoves at lists.bioenergylists.org
> >
> > Reply-To: Discussion of biomass cooking stoves
> > <stoves at lists.bioenergylists.org>
> > Subject: Re: [Stoves] Pot shells / Fin shells
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
>
>
>
>
>
> ------------------------------
>
> Message: 10
> Date: Sun, 28 Jul 2013 20:13:46 -0400
> From: "Lanny Henson" <lannych at bellsouth.net>
> To: "Discussion of biomass cooking stoves"
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] pellet gasifier (rice hull pellets)
> Message-ID: <1CEABD83642745448CC06C3BE6D4545E at HP>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Some very nice blue flames!!
> The second video is set to "private viewing"
> Lanny
>   ----- Original Message -----
>   From: Paul Olivier
>   To: Discussion of biomass cooking stoves
>   Sent: Sunday, July 28, 2013 7:06 PM
>   Subject: [Stoves] pellet gasifier (rice hull pellets)
>
>
>   In a more user-friendly format:
>
>   http://www.youtube.com/watch?v=Ss9lRB4SpOk
>
>   http://www.youtube.com/watch?v=84qDsbBO9p8
>
>
>   Thanks.
>
>   Paul Olivier
>
>
>   --
>   Paul A. Olivier PhD
>   26/5 Phu Dong Thien Vuong
>   Dalat
>   Vietnam
>
>   Louisiana telephone: 1-337-447-4124 (rings Vietnam)
>   Mobile: 090-694-1573 (in Vietnam)
>   Skype address: Xpolivier
>   http://www.esrla.com/
>
>
>
> ------------------------------------------------------------------------------
>
>
>   _______________________________________________
>   Stoves mailing list
>
>   to Send a Message to the list, use the email address
>   stoves at lists.bioenergylists.org
>
>   to UNSUBSCRIBE or Change your List Settings use the web page
>
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>
>   for more Biomass Cooking Stoves,  News and Information see our web site:
>   http://stoves.bioenergylists.org/
>
> -------------- next part --------------
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>
> ------------------------------
>
> Message: 11
> Date: Mon, 29 Jul 2013 07:44:07 +0700
> From: Paul Olivier <paul.olivier at esrla.com>
> To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] pellet gasifier (rice hull pellets)
> Message-ID:
>         <
> CAOreFvZoCnUBvjPtWXQn_uu4EdWv2Hs+ds0-UM9cx_66S_uYZA at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Lenny,
>
> Can you now view the second video?
>
> Paul
>
>
> On Mon, Jul 29, 2013 at 7:13 AM, Lanny Henson <lannych at bellsouth.net>
> wrote:
>
> > **
> > Some very nice blue flames!!
> > The second video is set to "private viewing"
> > Lanny
> >
> > ----- Original Message -----
> > *From:* Paul Olivier <paul.olivier at esrla.com>
> > *To:* Discussion of biomass cooking stoves<
> stoves at lists.bioenergylists.org>
> > *Sent:* Sunday, July 28, 2013 7:06 PM
> > *Subject:* [Stoves] pellet gasifier (rice hull pellets)
> >
> >  In a more user-friendly format:
> >
> > http://www.youtube.com/watch?v=Ss9lRB4SpOk
> >
> > http://www.youtube.com/watch?v=84qDsbBO9p8
> >
> > Thanks.
> > Paul Olivier
> >
> > --
> > Paul A. Olivier PhD
> > 26/5 Phu Dong Thien Vuong
> > Dalat
> > Vietnam
> >
> > Louisiana telephone: 1-337-447-4124 (rings Vietnam)
> > Mobile: 090-694-1573 (in Vietnam)
> > Skype address: Xpolivier
> > http://www.esrla.com/
> >
> > ------------------------------
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> >
>
>
> --
> Paul A. Olivier PhD
> 26/5 Phu Dong Thien Vuong
> Dalat
> Vietnam
>
> Louisiana telephone: 1-337-447-4124 (rings Vietnam)
> Mobile: 090-694-1573 (in Vietnam)
> Skype address: Xpolivier
> http://www.esrla.com/
> -------------- next part --------------
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>
> ------------------------------
>
> Message: 12
> Date: Mon, 29 Jul 2013 10:06:32 +0700
> From: Paul Olivier <paul.olivier at esrla.com>
> To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: [Stoves] pellets in an urban setting
> Message-ID:
>         <CAOreFvbAs23t4LswAcaOj4rV6MnorU8eUOpE7q0yUgg_=
> 5QfsA at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> I am getting excited about the use of pellets. In an urban setting in a
> developing country such as Vietnam, a pellet gasifier should be a lot more
> socially acceptable than a loose biomass gasifier.
>
> Since pellets can be as much as 8 to 10 times more dense than loose
> biomass, the reactor can be much smaller. A net reactor height of only 8
> inches is all that is needed to give a burn time of up to 90 minutes. Since
> the unit is small, it is  lightweight. The reactor weight is but 1.2 kg. It
> is easy to handle. With such a small reactor, the manufacturing cost drops
> considerably. This means that the most heat-resistant and non-corrosive
> stainless steels become affordable. This adds years to the life of the
> unit. This also means that the unit looks good and takes on the appearance
> of a high-end kitchen utensil. If the unit does not look good, it will be
> hard to sell.
>
>
> https://dl.dropboxusercontent.com/u/22013094/150%20Gasifier/Short/Photos/IMG_1571.JPG
>
> Pellets can be more cheaply transported into urban areas than loose
> biomass. Dealing with loose biomass can often be dusty and messy. The
> storage of pellets in a kitchen takes up much less space than the storage
> of loose biomass. With pellets there should be a lot less emissions of
> particulates.
>
> Biochar pellets are easier to quantify than loose biochar. A measurement of
> biochar volume is all that is needed. There is only a small reduction in
> volume as when a pellet is transformed into biochar.
>
> The flame put out by a pellet gasifier is rich and intense throughout the
> burn:
> http://www.youtube.com/watch?v=84qDsbBO9p8
> The flame does not turn ethereal.
>
> It is true that pellets cost more than loose biomass. But pellets are
> cheaper to transport into a city than loose biomass, and the biochar
> produced from pellets has a higher value in Vietnam than the original
> pellets. I foresee the possibility of an exchange program where pellets are
> supplied free-of-charge in exchange for the biochar produced from these
> pellets.
>
> Thanks.
> Paul Olivier
>
> --
> Paul A. Olivier PhD
> 26/5 Phu Dong Thien Vuong
> Dalat
> Vietnam
>
> Louisiana telephone: 1-337-447-4124 (rings Vietnam)
> Mobile: 090-694-1573 (in Vietnam)
> Skype address: Xpolivier
> http://www.esrla.com/
> -------------- next part --------------
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>
> ------------------------------
>
> Message: 13
> Date: Sun, 28 Jul 2013 20:42:33 -0700
> From: Todd Albi <todd.r.albi at gmail.com>
> To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Cajun Rocket Pot
> Message-ID:
>         <CAE3shSP+wS41dxEPeywE+VOt=
> pYgM3VwDLy0Ux7XOkYre-_-wQ at mail.gmail.com>
> Content-Type: text/plain; charset="windows-1252"
>
> Subject:  Cajun Rocket Pot / TLUD Soot
>
> Soot is an end product on all pots used on biomass stoves with or without
> fins or skirts.  Heat transfer is increased by adding more surface area to
> cooking pots with dowels, finned ribs, corrugated ribs, rows of fins or
> full skirted pots as discussed.  Steel woks with lamented cast iron bases
> with fins have been available in China for quite sometime.  We have both in
> our SilverFire showroom.   They are designed specifically for biomass.
> Finned pots specific for LPG have also been available for a number of
> years.
>
>  The Chinese Enron turbo pots have been marketed in the USA for several
> years (www.turbopot.com).   Rebates for Enron finned pots are available
> from utility companies in the USA for LPG savings.  The LPG fin design on
> Turbo pots differ significantly from the biomass design.  Narrow LPG finned
> pot channels clog with soot and the end result is that the soot negates
> heat transfer, if used with biomass.  Fin designs for biomass cooking are
> significantly wider and work well.  Time to boil is significantly reduced.
>
>  The ease of cleaning and product acceptance is also important, as Dale
> touched upon.  We had early prototypes of both fin pot & skirted pots
> fabricated in 2008.  I was not a proponent of the Aprovecho fin pot.  It
> made no sense for the end user.  The early design had fins that extended
> from the base and up the sidewalls of the pot.  We would have had to
> provide tetanus shots for end users, had that design ever reached the
> market.  The exterior design was unacceptable.  Cleaning or handling the
> pot was a handling hazard.
>
>  Our production pot we introduced to the introduced to the market was the
> skirted pot.  It cut approximately 5 minutes to time to boil in our early
> WBT work.  I brought the skirted pot to market though, for the important
> fact that we designed the skirt to protrude below the cast iron cook top.
> This important design feature reduced the chance of the pot sliding off the
> stove to prevent burning the cook or children.  Since soot did not
> accumulate on the exterior skirt, it also meant less cleaning for the cook,
> compared to the finned pot.  The skirted pot was more acceptable than our
> fin pot design.  Combining a skirt and fins would provide even greater heat
> transfer.  A well-designed pot must be easy to clean.
>
>  Todd Albi, SilverFire
>
>
>
> On Sun, Jul 28, 2013 at 11:26 AM, Tom Miles <tmiles at trmiles.com> wrote:
>
> > Is a TLUD likely to have less soot buildup on fins?****
> >
> > ** **
> >
> > Tom****
> >
> > ** **
> >
> > *From:* Stoves [mailto:stoves-bounces at lists.bioenergylists.org] *On
> > Behalf Of *Andreatta, Dale A.
> > *Sent:* Sunday, July 28, 2013 11:12 AM
> >
> > *To:* Discussion of biomass cooking stoves
> > *Subject:* Re: [Stoves] Cajun Rocket Pot****
> >
> > ** **
> >
> > I like it!!!****
> >
> > ** **
> >
> > As some of you know, I spent a lot of time around 2007-2008 working on
> > finned pots, and never really got them to work well.  I didn?t try this
> > type of ?pin fin? design because I couldn?t figure out how to make a
> > prototype.  ****
> >
> > ** **
> >
> > With this pin fin design (that?s what mechanical engineers call this
> shape
> > of fin) you increase the heat transfer area, but unlike the fins I worked
> > with, you don?t significantly change the flow of the gas.  You get high
> > convective heat transfer coefficients.  Hot gases impinging on a surface
> > (hitting the surface from a perpendicular direction) usually gives better
> > heat transfer than hot gases flowing parallel to a surface.  The basic
> > tests that have been done prove this, at least with industrial fuel
> > flames.  ****
> >
> > ** **
> >
> > I expect that with a sooty flame, you could use a brush to scrape off
> most
> > of the soot, and what you don?t get this time you can get next time.
>  Thin
> > layers of soot wouldn?t have much effect.  Perhaps arranging the fins in
> > rows rather than circular arrays would make them easier to clean quickly.
> > ****
> >
> > ** **
> >
> > I expect that emissions per unit of time will increase, since you are
> > quenching the flame more quickly at the bottom of the pot and stopping
> the
> > reactions that would otherwise burn up some of particles and CO.  The
> > effect might be small or large.  On the other hand, if the time to boil
> is
> > greatly reduced, the total emissions might be a lot less.  ****
> >
> > ** **
> >
> > I expect that you could make a pot out of cast aluminum with the fins
> cast
> > in place.  You could use tapered pins to save material and improve
> > castability.  You could probably also use sophisticated welding
> techniques,
> > as has been described, or possibly furnace brazing techniques.  ****
> >
> > ** **
> >
> > The material of the pot doesn?t make much difference.  Since all metals
> > are much better conductors of heat than gases, it doesn?t matter whether
> > the metal is much better at conducting (stainless steel) or much much
> > better at conducting (aluminum).  It would mostly then be a cost and
> > manufacturing issue.  ****
> >
> > ** **
> >
> > The fins must be bonded (welded, brazed, soldered, cast in place) to the
> > pot itself, otherwise there is too much resistance to heat transfer
> across
> > the interface.  ****
> >
> > ** **
> >
> > What to do next?  Where does one get one?  If I can get a sample I could
> > test it out on a variety of stoves, rocket, charcoal, open fire,
> gasifier,
> > LPG, fire-in-a-bucket, etc.  I could prepare a quick report by the next
> > ETHOS time.  Or, someone who does experimental work full time, such as
> Apro
> > or many other labs, could do a better job in less time.  What I?m saying
> is
> > that this is a very exciting development, that could make a huge
> difference
> > in what we do.  We should pursue this quickly.****
> >
> > ** **
> >
> > Dale Andreatta, Ph.D., P.E.****
> >
> > ** **
> >
> > ** **
> >
> > ** **
> >
> > *From:* Stoves [mailto:stoves-bounces at lists.bioenergylists.org<
> stoves-bounces at lists.bioenergylists.org>]
> > *On Behalf Of *Dean Still
> > *Sent:* Sunday, July 28, 2013 11:36 AM
> > *To:* Discussion of biomass cooking stoves
> > *Subject:* Re: [Stoves] Cajun Rocket Pot/ capacitive discharge stud
> weldie
> > ****
> >
> > ** **
> >
> > Hi Lanny,****
> >
> > ** **
> >
> > We tested a couple of pots with fins but the space between the fins
> > clogged up quickly with soot, a good insulator.****
> >
> > ** **
> >
> > Best,****
> >
> > ** **
> >
> > Dean****
> >
> > On Sun, Jul 28, 2013 at 5:21 AM, Lanny Henson <lannych at bellsouth.net>
> > wrote:****
> >
> > ** **
> >
> > Lanny have you seen capacitive discharge stud welding?****
> >
> >
> > Yes I have a stud welder but I did not realize it would weld dissimilar
> > metals especially aluminum to anything else.
> >
> > Stud welding is very finicky and will leave a blemish on the opposite
> side
> > of thin metal.
> >
> > When a stud weld fails you have to grind the surface to clean it up
> before
> > rewelding.. How are you going to do that if it is between the other
> studs?
> >
> > Attaching studs, fins or anything to a pot is going to be problematic,
> but
> > attaching something to the pot holder may be practical. The heat transfer
> > may not be as good as having something attached to the pot but it could
> > possibly improve the heat transfer.
> >
> > Lanny Henson
> >
> > ----- Original Message ----- From: <ajheggie at gmail.com>
> > To: "Discussion of biomass cooking stoves" <
> > stoves at lists.bioenergylists.org>
> > Sent: Sunday, July 28, 2013 5:23 AM
> > Subject: Re: [Stoves] Cajun Rocket Pot****
> >
> > [Default] On Sat, 27 Jul 2013 20:48:02 -0400,"Lanny Henson"
> > <lannych at bellsouth.net> wrote:****
> >
> > I like creative people and take no pleasure criticizing their work but it
> > is going to be too expensive and difficult to make with all the pegs.****
> >
> >
> > Lanny have you seen capacitive discharge stud welding? This would
> > allow welding of dissimilar metals to the pot in any pattern. I have
> > no idea of costs.
> >
> > Have you done heat transfer tests with your 4mm aluminium pot compared
> > with the thinner stainless one? Stainless is a notoriously poor
> > conductor of heat and theoretically would need to be just under a
> > tenth of the thickness of aluminium for the same conductivity, but I
> > do use stainless pots at home.
> >
> > Finally can you explain the difference between a vat and a pot?
> >
> > Paul I do consider this to be important because biomass stoves have an
> > inherent problem with heat transfer compared with natural gas or LPG
> > so improvements in heat exchange will have high benefits.
> >
> > AJH****
> >
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/****
> >
> > ** **
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> >
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>
> ------------------------------
>
> Message: 14
> Date: Mon, 29 Jul 2013 06:48:11 -0400
> From: Jonathan P Gill <jg45 at icloud.com>
> To: Discussion of biomass cooking stoves
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Cajun Rocket Pot
> Message-ID: <58747FE9-BA0A-47E9-9C91-90B144013F46 at icloud.com>
> Content-Type: text/plain; charset="windows-1252"
>
> Todd,
>
> I find that a TLUD with a well tuned air/fuel mix, that also has good
> turbulence in the mix, will produce little soot on pot bottoms.  Proper
> carburation of a turbulent fuel air mix makes for a cleaner burning TLUD.
>
> Excessive soot build up is a good indication that the carburation and
> turbulence of the mix are sub optimal.
>
> Regards,
>
> Jock
>
> On Jul 28, 2013, at 11:42 PM, Todd Albi <todd.r.albi at gmail.com> wrote:
>
> > Subject:  Cajun Rocket Pot / TLUD Soot
> >
> > Soot is an end product on all pots used on biomass stoves with or
> without fins or skirts.  Heat transfer is increased by adding more surface
> area to cooking pots with dowels, finned ribs, corrugated ribs, rows of
> fins or full skirted pots as discussed.  Steel woks with lamented cast iron
> bases with fins have been available in China for quite sometime.  We have
> both in our SilverFire showroom.   They are designed specifically for
> biomass.  Finned pots specific for LPG have also been available for a
> number of years.
> >
> >  The Chinese Enron turbo pots have been marketed in the USA for several
> years (www.turbopot.com).   Rebates for Enron finned pots are available
> from utility companies in the USA for LPG savings.  The LPG fin design on
> Turbo pots differ significantly from the biomass design.  Narrow LPG finned
> pot channels clog with soot and the end result is that the soot negates
> heat transfer, if used with biomass.  Fin designs for biomass cooking are
> significantly wider and work well.  Time to boil is significantly reduced.
> >
> >
> >  The ease of cleaning and product acceptance is also important, as Dale
> touched upon.  We had early prototypes of both fin pot & skirted pots
> fabricated in 2008.  I was not a proponent of the Aprovecho fin pot.  It
> made no sense for the end user.  The early design had fins that extended
> from the base and up the sidewalls of the pot.  We would have had to
> provide tetanus shots for end users, had that design ever reached the
> market.  The exterior design was unacceptable.  Cleaning or handling the
> pot was a handling hazard.
> >
> >
> >  Our production pot we introduced to the introduced to the market was
> the skirted pot.  It cut approximately 5 minutes to time to boil in our
> early WBT work.  I brought the skirted pot to market though, for the
> important fact that we designed the skirt to protrude below the cast iron
> cook top.  This important design feature reduced the chance of the pot
> sliding off the stove to prevent burning the cook or children.  Since soot
> did not accumulate on the exterior skirt, it also meant less cleaning for
> the cook, compared to the finned pot.  The skirted pot was more acceptable
> than our fin pot design.  Combining a skirt and fins would provide even
> greater heat transfer.  A well-designed pot must be easy to clean.
> >
> >
> >  Todd Albi, SilverFire
> >
> >
> >
> >
> > On Sun, Jul 28, 2013 at 11:26 AM, Tom Miles <tmiles at trmiles.com> wrote:
> > Is a TLUD likely to have less soot buildup on fins?
> >
> >
> >
> > Tom
> >
> >
> >
> > From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf
> Of Andreatta, Dale A.
> > Sent: Sunday, July 28, 2013 11:12 AM
> >
> >
> > To: Discussion of biomass cooking stoves
> > Subject: Re: [Stoves] Cajun Rocket Pot
> >
> >
> >
> > I like it!!!
> >
> >
> >
> > As some of you know, I spent a lot of time around 2007-2008 working on
> finned pots, and never really got them to work well.  I didn?t try this
> type of ?pin fin? design because I couldn?t figure out how to make a
> prototype.
> >
> >
> >
> > With this pin fin design (that?s what mechanical engineers call this
> shape of fin) you increase the heat transfer area, but unlike the fins I
> worked with, you don?t significantly change the flow of the gas.  You get
> high convective heat transfer coefficients.  Hot gases impinging on a
> surface (hitting the surface from a perpendicular direction) usually gives
> better heat transfer than hot gases flowing parallel to a surface.  The
> basic tests that have been done prove this, at least with industrial fuel
> flames.
> >
> >
> >
> > I expect that with a sooty flame, you could use a brush to scrape off
> most of the soot, and what you don?t get this time you can get next time.
>  Thin layers of soot wouldn?t have much effect.  Perhaps arranging the fins
> in rows rather than circular arrays would make them easier to clean quickly.
> >
> >
> >
> > I expect that emissions per unit of time will increase, since you are
> quenching the flame more quickly at the bottom of the pot and stopping the
> reactions that would otherwise burn up some of particles and CO.  The
> effect might be small or large.  On the other hand, if the time to boil is
> greatly reduced, the total emissions might be a lot less.
> >
> >
> >
> > I expect that you could make a pot out of cast aluminum with the fins
> cast in place.  You could use tapered pins to save material and improve
> castability.  You could probably also use sophisticated welding techniques,
> as has been described, or possibly furnace brazing techniques.
> >
> >
> >
> > The material of the pot doesn?t make much difference.  Since all metals
> are much better conductors of heat than gases, it doesn?t matter whether
> the metal is much better at conducting (stainless steel) or much much
> better at conducting (aluminum).  It would mostly then be a cost and
> manufacturing issue.
> >
> >
> >
> > The fins must be bonded (welded, brazed, soldered, cast in place) to the
> pot itself, otherwise there is too much resistance to heat transfer across
> the interface.
> >
> >
> >
> > What to do next?  Where does one get one?  If I can get a sample I could
> test it out on a variety of stoves, rocket, charcoal, open fire, gasifier,
> LPG, fire-in-a-bucket, etc.  I could prepare a quick report by the next
> ETHOS time.  Or, someone who does experimental work full time, such as Apro
> or many other labs, could do a better job in less time.  What I?m saying is
> that this is a very exciting development, that could make a huge difference
> in what we do.  We should pursue this quickly.
> >
> >
> >
> > Dale Andreatta, Ph.D., P.E.
> >
> >
> >
> >
> >
> >
> >
> > From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf
> Of Dean Still
> > Sent: Sunday, July 28, 2013 11:36 AM
> > To: Discussion of biomass cooking stoves
> > Subject: Re: [Stoves] Cajun Rocket Pot/ capacitive discharge stud weldie
> >
> >
> >
> > Hi Lanny,
> >
> >
> >
> > We tested a couple of pots with fins but the space between the fins
> clogged up quickly with soot, a good insulator.
> >
> >
> >
> > Best,
> >
> >
> >
> > Dean
> >
> > On Sun, Jul 28, 2013 at 5:21 AM, Lanny Henson <lannych at bellsouth.net>
> wrote:
> >
> >
> >
> > Lanny have you seen capacitive discharge stud welding?
> >
> >
> > Yes I have a stud welder but I did not realize it would weld dissimilar
> metals especially aluminum to anything else.
> >
> > Stud welding is very finicky and will leave a blemish on the opposite
> side of thin metal.
> >
> > When a stud weld fails you have to grind the surface to clean it up
> before rewelding.. How are you going to do that if it is between the other
> studs?
> >
> > Attaching studs, fins or anything to a pot is going to be problematic,
> but attaching something to the pot holder may be practical. The heat
> transfer may not be as good as having something attached to the pot but it
> could possibly improve the heat transfer.
> >
> > Lanny Henson
> >
> > ----- Original Message ----- From: <ajheggie at gmail.com>
> > To: "Discussion of biomass cooking stoves" <
> stoves at lists.bioenergylists.org>
> > Sent: Sunday, July 28, 2013 5:23 AM
> > Subject: Re: [Stoves] Cajun Rocket Pot
> >
> > [Default] On Sat, 27 Jul 2013 20:48:02 -0400,"Lanny Henson"
> > <lannych at bellsouth.net> wrote:
> >
> > I like creative people and take no pleasure criticizing their work but
> it is going to be too expensive and difficult to make with all the pegs.
> >
> >
> > Lanny have you seen capacitive discharge stud welding? This would
> > allow welding of dissimilar metals to the pot in any pattern. I have
> > no idea of costs.
> >
> > Have you done heat transfer tests with your 4mm aluminium pot compared
> > with the thinner stainless one? Stainless is a notoriously poor
> > conductor of heat and theoretically would need to be just under a
> > tenth of the thickness of aluminium for the same conductivity, but I
> > do use stainless pots at home.
> >
> > Finally can you explain the difference between a vat and a pot?
> >
> > Paul I do consider this to be important because biomass stoves have an
> > inherent problem with heat transfer compared with natural gas or LPG
> > so improvements in heat exchange will have high benefits.
> >
> > AJH
> >
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> >
> > to Send a Message to the list, use the email address
> > stoves at lists.bioenergylists.org
> >
> > to UNSUBSCRIBE or Change your List Settings use the web page
> >
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
> >
> > for more Biomass Cooking Stoves,  News and Information see our web site:
> > http://stoves.bioenergylists.org/
> >
>
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>
> ------------------------------
>
> Message: 15
> Date: Mon, 29 Jul 2013 07:57:49 -0700
> From: "Richard Stanley" <rstanley at legacyfound.org>
> To: <rongretlarson at comcast.net>
> Cc: 'Daniel Roggema' <droggema at gmail.com>,      'Discussion of biomass'
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Hand-makng small roundish briquettes:
> Message-ID: <017601ce8c6b$fee123c0$fca36b40$@legacyfound.org>
> Content-Type: text/plain; charset="us-ascii"
>
> Ron,
>
> Often squeezing pressure is th the solution. Its most often about blending
> hte right amount of fibrus material and combustible infiller. Its the
> combination of fibers that are conditioned to flex plastically and
> infilling
> material that is dense yet relatively porous, With the right combination
> you
> can indeed create denst briquetts by hand without , no amount of force will
> create a good briquette. I do not knwo what aprovecho uses as we lost
> contact with them after they visited here to gather what we were doing, but
> I would say that it is very likely that if you found paper blends there (
> and fomr your description they are paper based) it would be workable but
> paper is far from the ideal in terms of  good hot combustion.
>
> So its easy to dive in and make a pancake  but to get to crepes.
>
>
>
> Assuming you are using a realtively good blend,  Here is a multiport
> cylinder design we came up with a few years ago: please note that I have
> never built it! So caveat emptor eh ..
>
>
>
>
> cid:B4F8D033-20B0-4FE7-A18E-18970856D934cid:09B0D435-697B-409F-801E-31C76A3D
>
> F1AEcid:0B5B0BD7-00CF-4723-A084-F6A2EC70AB81cid:81C20FB2-F69B-49DD-BACF-8579
>
> 0D11082Dcid:F91FF435-FB21-43D5-9C81-D5BAB32884A7cid:3348FDD0-C53F-429A-B212-
> 26F76E17A4FCcid:BA77C963-3C32-4F5F-925A-6879171BE6BBAgh but the greatest
> plans of mice and men often go astray..
>
> IE., with the above options it'd be relatively easy to findout which would
> work best with realtivley little investment in time and materials..Go
> astray
> you may but may you return wiser for another day.
>
>
>
> . I would also invite you to contact Lee Hite for his rectangular stick
> briquettes  for on his ingenious micro compound lever briquette press,
> which
> he has built and tested both in His Ohio base and in many parts of the
> thrid
> world we well.
>
>
>
>
> http://www.cleanstove.org/1/post/2011/12/meetup-with-lee-hite-zan-smith-and-
> ron-gorley.html
>
>
>
>  or consult Paul Anderson to see how his wedgies worked out.
>
>
>
>
>
> On Jul 27, 2013, at 4:16 PM, rongretlarson at comcast.net wrote:
>
>
>
> List:
>
>     This below is the follow-up from a few minutes ago,  when I wrote on
> this list
>        " I am going to write something next about my thoughts after trying
> to produce a third shaped-briquette"..
>
>    This below is from from the perspective of using briquettes in TLUDs,
> where (except for in the last note),  I haven't seen any way to as easily
> make char as in a TLUD.   The holey briquette approach championed by
> Richard
> Stanley gives some very nice flames in modified rockets, but those
> briquettes are being broken up to use in TLUDs.  I think the same will be
> true for the long rectangular "sticks" being produced by InStove folk in
> Cottage Grove
>
>     The question I have had in mind for a long time is whether there is a
> "best" shape for briquettes intended for TLUDs.  So I took the opportunty
> to
> get my hands wet (literally) when I found several large vats of material
> prepared for our (and InStove) experiments.  I (and a few others, but
> others
> just for a few minutes)  tried making small spheres  (small -  thinking I
> might need a sphere diameter in the range of 1/5-1/10 of a chamber
> diameter)
> - so never more than 3-4 cm.  The first attempts all seemed to keep coming
> out more like small snowballs.  I cut many of the larger in half and,
> repacking, still got a sphere that seemed too big.
>
>     Even when getting down to a relatively small size, the hand-packing
> ddn't seem natural.  I couldn't see a way to make a sphere with one hand -
> and it was only after quite a while that I got down to four
> "water-squeezes", using both hands,  that the quasi-sphere looked worth
> testing in a stove.   I still don't know if that has been done  - as drying
> was not complete enough as of yesterday afternoon.   The final "dry"
> density
> seemed pretty loose - but no worse than other briquettes sitting around and
> a lot better than some..
>
>     Yesterday,  I tried a few more experiments.  I found that I could move
> much faster making long "ellipsoids" - creating a fist with the paper pulp
> inside the fist shape.  I used my left hand with just one squeeze and
> passing to the right hand,for a second squeeze  (imagine milking a cow).
> Eventually, I  was moving pretty fast - when I could be squeezing two units
> with two hands at the same time.  The final product was sort of like a
> "furry" finger or a  furry link-breakfast-sausage  (other makers will
> surely
> think of another biological shape whose name is not to be used in polite
> internet traffic).  No test results, but again the same feeling that the
> density was pretty good  (that the human hand can produce a quite strong
> squeeze, when directed of a surface area  that is not too large.).
>
>    One advantage of this approach could be more kg per hour.  It may fit
> well with a social gathering - no needed movement from a sitting position.
> Another is zero capital equipment expense.  But mainly,  the advantage is
> in
> having a final briquette fuel shape that fits with TLUD designs - at least
> the larger
>
>    I look forward to hearing that others have tried "t*rdquettes" in a
> stove.
>
> Ron
>
>
>
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> ------------------------------
>
> Message: 16
> Date: Mon, 29 Jul 2013 09:16:22 -0700
> From: Richard Stanley <rstanley at legacyfound.org>
> To: rongretlarson at comcast.net
> Cc: daniel roggema <droggema at gmail.com>,        Discussion of biomass
>         <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Hand-makng small roundish briquettes:
> Message-ID: <CFA3D31E-EFD6-43F4-BAE0-637212426725 at legacyfound.org>
> Content-Type: text/plain; charset="windows-1252"
>
> Ron, daniel et al.
> Apologies for my atrocious spelling.
> Here is what I was trying to say:
>
> Ron,
> Often greater squeezing pressure (to achieve greater density) is NOT the
> solution. It  is most often about blending the right amount of fibrus
> material and combustible infiller. Its about attaining the right
> combination of fibers that are conditioned to flex plastically with an
> infilling material that is dense yet relatively porous.  No amount of force
> will create a good briquette using the wet process becsue increased
> pressure results in shearing of the fibers and  vaporising the water in the
> slurry, creating a crude form of steam cannon.
> I do not know what blend Approvecho uses as we lost contact with them
> after they visited here to gather what we were doing, but I would say that
> it is very likely that if you found paper blends there. Relatively dense
> briquettes can be achieved  with paper-based blends by hand  but paper is
> far from the ideal in terms of  good hot combustion?
> Thanks for your patience,
> Richard Stanley
> =====
>
>
>
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> ------------------------------
>
> Message: 17
> Date: Mon, 29 Jul 2013 17:24:47 +0000 (UTC)
> From: rongretlarson at comcast.net
> To: Paul Olivier <paul.olivier at esrla.com>,      Discussion of biomass
>         cooking stoves <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] pellets in an urban setting
> Message-ID:
>         <
> 399017469.1648004.1375118687377.JavaMail.root at sz0133a.emeryville.ca.mail.comcast.net
> >
>
> Content-Type: text/plain; charset="utf-8"
>
> Paul and cc list (but the questions below pertinent to any and all)
>
> This is to hope that you can perform a few more experiments re fuels. I am
> sure all your comments are correct comparing loose husks to pellets, but
> wonder if you could try and report on several other fuel options as well -
> especially telling us about prices in Vietnam. Your comment about running
> stoves for free because char produced in your stove is worth more than the
> pellets going in is very important. Can you give more cost (per kilo)
> detail on that? The next three (are there more?) items are extensions -
> both on technical results and on economics.
>
> First is wood chips. The stove camp activity was all based on this product
> because of a request from a South American (?) company wanting to harvest a
> large older forest, I think specifically planted decades ago to save nearby
> old growth forests. I presume chips are being preferred over pellets for
> cost reasons (I have heard a 3:1 price difference). Hopefully you can find
> a chip supply and tell us on their performance and economics in any of your
> stoves as well.
>
> Second is any fuel made by hand from paper, leaves, grasses, rice husks
> (?), etc - as promoted by Richard Stanley, etal. Presumably you saw my
> recent report on making something specifically for TLUDs. The advantages
> here are making productive use of materials having no other possible use
> and supplying jobs for low-income people. I am about also to respond to
> recent message from Richard along these lines (re using only hand muscles).
>
> Third is use of small twigs, ag residues, straws, reeds, grasses, etc
> (similar to rice husks, but denser and available where husks are not) that
> can be used without any processing.. Again, maybe a job creator - with hope
> that the char value exceeds the fuel cost This presently is the fuel of
> choice for backpackers as it can be found everywhere. Can this approach be
> expanded, again as a way for fuel preparers and cooks to make money rather
> than only expend it?
>
> Fourth (and last) is the supply of larger wood (maybe only branches?) cut
> into small pieces (I saw a lot from board lumber cut to about 6-12 inch
> length almost all less than 1 square inch cross-section (NOT the standard
> fuel in the field). This was the main fuel alternative to chips at the
> stove camp for those not using TLUDs. Presumably this is also possible in
> Vietnam for vertical stacking in your device with optimum heights and
> packing densities. Again emphasis to be on economics - still hoping to find
> lower fuel costs than pellets, but less bulky than husks, if possible.
>
> I pick on you as probably having some local labor available to try these
> alternatives with a chance of selling more stoves where costs can be an
> important factor - and you knowing of the importance of either getting more
> char in the ground or of making char with use of the pyrolysis gases. I'll
> be glad to split the costs of trying these other quite-different fuel
> options in your stove.
>
> Somewhat along these lines, this is also to alert all to an EPA-GACC
> webinar on 20 August on batch stoves (10:00 AM Eastern). This received a
> few days ago:
> The online registration form (
> https://unfoundation.conferencinghub.com/attendee/RegisterLogin.aspx?hubconfID=1632144&qtID=1&act=reg&cp=2861) includes a place to enter comments or questions you would like addressed
> during the webinar.
>
>
>
> So Paul, thanks in advance for anything new you can report on the
> economics of these six fuel options.
>
> Ron
>
> ----- Original Message -----
> From: "Paul Olivier" <paul.olivier at esrla.com>
> To: "Discussion of biomass cooking stoves" <
> stoves at lists.bioenergylists.org>
> Sent: Sunday, July 28, 2013 9:06:32 PM
> Subject: [Stoves] pellets in an urban setting
>
>
>
>
> I am getting excited about the use of pellets. In an urban setting in a
> developing country such as Vietnam, a pellet gasifier should be a lot more
> socially acceptable than a loose biomass gasifier.
>
> Since pellets can be as much as 8 to 10 times more dense than loose
> biomass, the reactor can be much smaller. A net reactor height of only 8
> inches is all that is needed to give a burn time of up to 90 minutes. Since
> the unit is small, it is lightweight. The reactor weight is but 1.2 kg. It
> is easy to handle. With such a small reactor, the manufacturing cost drops
> considerably. This means that the most heat-resistant and non-corrosive
> stainless steels become affordable. This adds years to the life of the
> unit. This also means that the unit looks good and takes on the appearance
> of a high-end kitchen utensil. If the unit does not look good, it will be
> hard to sell.
>
>
> https://dl.dropboxusercontent.com/u/22013094/150%20Gasifier/Short/Photos/IMG_1571.JPG
>
> Pellets can be more cheaply transported into urban areas than loose
> biomass. Dealing with loose biomass can often be dusty and messy. The
> storage of pellets in a kitchen takes up much less space than the storage
> of loose biomass. With pellets there should be a lot less emissions of
> particulates.
>
> Biochar pellets are easier to quantify than loose biochar. A measurement
> of biochar volume is all that is needed. There is only a small reduction in
> volume as when a pellet is transformed into biochar.
>
> The flame put out by a pellet gasifier is rich and intense throughout the
> burn:
> http://www.youtube.com/watch?v=84qDsbBO9p8
>
> The flame does not turn ethereal.
>
>
>
> It is true that pellets cost more than loose biomass. But pellets are
> cheaper to transport into a city than loose biomass, and the biochar
> produced from pellets has a higher value in Vietnam than the original
> pellets. I foresee the possibility of an exchange program where pellets are
> supplied free-of-charge in exchange for the biochar produced from these
> pellets.
>
>
> Thanks.
> Paul Olivier
>
>
>
>
>
>
>
> --
> Paul A. Olivier PhD
> 26/5 Phu Dong Thien Vuong
> Dalat
> Vietnam
>
> Louisiana telephone: 1-337-447-4124 (rings Vietnam)
> Mobile: 090-694-1573 (in Vietnam)
> Skype address: Xpolivier
> http://www.esrla.com/
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> ------------------------------
>
> End of Stoves Digest, Vol 35, Issue 22
> **************************************
>



-- 
Art Donnelly
President SeaChar.Org
US Director, The Farm Stove Project
Proyecto Estufa Finca
<http://email2.globalgiving.org/wf/click?c=1Oy%2FmZbgIyjS5WI580KXwShvfKBcF2eaJvtN7Pi6p7Jl%2FiR4938EMMCBwY%2FuYALeA%2BQYUWN4RpvnxBsBC7e2%2BGIHcONTozBmvsUU5LTL%2FTNk4Q3vxE%2BKdXTV2cxIsFplSPh%2F9nMG3bQMQf4bz9ZK9SHMy46Z8OPLAtMAnPG9SKkPuLCWvofBTLC%2BImqax%2BZTkkF2RvDri5UdgH19NHjHOBj5WMUrS4L62Z2xxUJbBsJdDUOfeifheNFXH546Xm0yul4P2stm%2FTUOJxYnI0nFjXEaYfzxDSc%2FwgqVkR1t0USDHk30%2Fgt9UpDpyzLj37HWtnNQ0q8Jh1gZCkB4Y1Fgbg394gYFkyNqFN4MchxO2Js%3D&rp=wrhiOr2wAxUyDMDlMSqbOkKa0FpPoiCSHffb%2ByfHGClRxIFjEIrUDwAF%2BFD%2BpAPuvam9BDwvSMcadhFv7aFwKoyAXYrFk00%2B92xPIeMHXaTDJ3x0VIj6ZYwjm1win65o&up=YDTqBOjidbCUo%2Far1oAtZjp5ji73zPEvmoO14mevuXzIDUdb6Ac9W13SPOXmzL5NflZkH0HxLp0v4dT9UwEHDV0wSZ1qusv09bIKkUliWs4%3D&u=LHuflw_1TAib_lgCu2JvQw%2Fh0>
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