[Stoves] Stoves Digest, Vol 2, Issue 11

[A.S.K. Weerakkody]

There is a method, I know, to get a continuous gas flow, easily applicable
to Alexis' type of stove.
Flu Gas from gasifier is collected inside a floating cylinder, which rises
up above water as gas pressure builds up. When time comes to remove and
re-load the gasifier, there is adequate gas under pressure inside the
cylinder for continuous operation. A small blower should be fitted to send
flu gas to the cylinder.

Ananda
Engr.Ananda Weerakkody
MSc(Eng), MIMgt(UK) & ISO9000-Lead Assessor.
Philippines & Sri Lanka


On 8/7/06, stoves-request at listserv.repp.org <
stoves-request at listserv.repp.org> wrote:
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> Today's Topics:
>
>   1. Re: [Gasification] Heating/thermal usage -        China
>      workshopnotes (Alex and Christine English)
>   2. Re: partial fan compensation by static-mixers? (Paul S. Anderson)
>   3. Re: [Gasification] Heating/thermal usage -        China
>      workshopnotes (Paul S. Anderson)
>   4. Re: Designs (Mukunda)
>   5. Re: [Gasification] Heating/thermal usage -        China
>      workshopnotes (psanders at ilstu.edu)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 7 Aug 2006 06:11:32 -0400
> From: "Alex and Christine English" <english at kingston.net>
> Subject: Re: [Stoves] [Gasification] Heating/thermal usage -    China
>        workshopnotes
> To: "Kevin Chisholm" <kchisholm at ca.inter.net>
> Cc: stoves at listserv.repp.org
> Message-ID: <44D6D994.27848.192FA1 at localhost>
>
> Kevin,
> One possible way would be to have two or more fuel chambers connected to a
> single
> burner. A flap valve would allow the transition from the spent chamber to
> the newly
> ignited one.
> Alex
>
> > Dear Ken Et Al
> >
> > The T-LUD is indeed a neat piece of equipment, and it certainly works
> well
> > for a heating application of short duration.
> >
> > I must be missing something, but I can't see a simple way to operate a
> T-LUD
> > stove on a continuous basis. If more fuel is added on the top surface of
> a
> > T-LUD fuel bed, it then becomes a "Thin Bed Updraft Gasifier", a "TBUG".
> >
> > It seems to me that the essence of a T-LUD is that there is no fuel
> above
> > the primary reaction zone, where the fuel is gasified, and that it is
> close
> > coupled to a secondary zone, where gases are burned to completion.
> >
> > Would someone be able to explain how a device that was started up as a
> T-LUD
> > could be operated on a continuous basis as a T-LUD?
> >
> > Thanks.
> >
> > Kevin
> > -----
> > > Paul,  Stovers and gasification enthusiasts,
> > >
> > > Thankyou for your report on the proceedings of the ARECOP
> workshop.  Most
> > > interesting reading.
> > >
> > > It appears to me that applications 3,4,5 and 6 (below) could be met
> with a
> > > T-LUD gasifier of between 20cm and 30 cm diameter.
> > >
> > > Might this be a common designed element for these projects that could
> be
> > > optimised and shared amongst the participants?
> > >
> > > regards
> > >
> > > Ken Boak
> > >
> > > London
> > >
> > >
> > >> 3.  Abdul Shakoor Sindhu of Pakistan is looking to have relatively
> small
> > > T-LUD
> > >> gasifiers provide the heat for the tandoor (tandoori) ovens that are
> used
> > > to
> > >> bake roti and other things.
> > >>
> > >> 4.  C. K. Kumarswamy of Bangalore, India, is focused on the
> relatively
> > > large
> > >> cookstoves of the roadside restaurants.  High heat is needed for
> several
> > > hours
> > >> at 3 meal times per day.  Fuel consumption currently is about 3 kg of
> > >> wood
> > > per
> > >> hour per stove (number of pots per stove is not in my notes.).  Some
> form
> > > of
> > >> T-LUD is to be used.
> > >>
> > >> 5.  From two different cities (500 km apart) in Indonesia, Dang
> > >> Tanoewiangga and
> > >> Hermanto Sudjarwo are interested in two food products made from
> palms.
> > > Both
> > >> products involve boiling away the water.  One is to make palm oil
> from
> > >> palm sap
> > >> collected from the trunks of some palm trees.  The other is to make
> > > coconut
> > >> brown sugar from the juice of the white coconut meat (copra).  These
> use
> > >> round-bottom pots of about 30 - 40 liters, and are stirred almost
> > >> constantly to
> > >> evaporate about 24 kg of water, leaving about 6 kg of oil.  T-LUD
> > >> gasifiers with
> > >> fuel chambers of 20 cm Diameter x 70 - 90 cm Height (or 30 cm D x 50
> -
> > >> 70 cm H)
> > >> are recommended for the approximately 4-hour process that currently
> uses
> > > about
> > >> 2 kg of wood per hour.
> > >>
> > >> 6.  Rajan Thapa of Nepal explained the seasonal production (Dec to
> March)
> > > of
> > >> Lapsi candy made from fruit.  The 100 liter pots (half-barrel of 55
> gal
> > > drums)
> > >> need to come to a boil and then simmer, for a total of 2 hours.  The
> > >> calculated
> > >> size of the fuel chamber of an appropriate T-LUD gasifier is 30 cm D
> x
> > >> 35 cm H.
> > >> (We hope to have a taste of the Lapsi candy and the coconut brown
> sugar
> > >> at
> > > the
> > >> 2007 meeting in Bangalore.)
> > >
> > >
> > >
> > >
> > > _______________________________________________
> > > Stoves mailing list
> > > Stoves at listserv.repp.org
> > > http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
> >
> >
> > _______________________________________________
> > Stoves mailing list
> > Stoves at listserv.repp.org
> > http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
> >
> >
>
>
>
>
>
>
> ------------------------------
>
> Message: 2
> Date: Mon, 07 Aug 2006 08:45:25 -0500
> From: "Paul S. Anderson" <psanders at ilstu.edu>
> Subject: Re: [Stoves] partial fan compensation by static-mixers?
> To: "Boll, Martin Dr." <boll.bn at t-online.de>
> Cc: Stoves-List <stoves at listserv.repp.org>
> Message-ID: <20060807084525.98pblvcadcsckooo at webmail2.ilstu.edu>
> Content-Type: text/plain;       charset=ISO-8859-1;     format="flowed"
>
> Dear Martin and all,
>
> I like the term "static mixers".  I believe that would be the placement of
> "barriers" into the stream of gases/flames.  If more than that, please
> explain.
>
> The stove camp focus on fans/forced air is for both or either primary or
> secondary air, not just for the mixing issues.
>
> Last year at stove camp, the focus was on natural draft.  The winner of
> the "Cat
> Pee" award for clean combustion was my T-LUD stove that I subsequently
> named the
> "Champion" stove.  In that unit, there is a 6-inch diameter 15-inch
> vertical
> chamber for combustion of the generated gases that enter from below
> through a
> 3-inch diameter central hole in the "concentrator disk" (could probably be
> called a throat).  As the flames rise in the combustion chamber, there
> should
> be plenty of space for some static mixers (barrier types).  I could
> easily hang
> them from the upper lip of the combustion chamber (or set them on top of
> the
> concentrator disk).  I have thought of this several times, but have not
> yet
> done anything serious about the topic.
>
> So I express my interest and ask for suggestions.
>
> Related to this, I desire some form(s) of "flame holder" that will assist
> in
> maintaining ignition of the gases in the advent of some disruption of the
> gas
> flow or flame.
>
> I leave to Stove Camp on Saturday AM, so I hope suggestions arrive in time
> for
> me to fabricate some to take with me and have tested in the Aprovecho
> testing
> facilities.
>
> Suggestions should be as specific as possible but also tell me of the
> amount of
> size changes that could be allowed.  I will be using materials from my
> stock of
> tincanium supplies plus hardware stove materials.  Please discuss the
> vertical
> placement aspects as well:  How high above the concentrator disk?  Should
> different heights be tested?
>
> I will see what I can do.
>
> Paul
>
> --
> Paul S. Anderson, Ph.D., Geography professor - Emeritus
> Telephone:  USA-309-452-7072 (residence and office)
> Internet site:  www.ilstu.edu/~psanders
> For my gasifier stoves info, go to:
> http://bioenergylists.org/contributors#Paul_Anderson
>
>
> Quoting "Boll, Martin Dr." <boll.bn at t-online.de>:
>
> > Tom, Andrew, Dean
> >
> >
> >
> > and to all now discussing the possible advantage of the Swosthee-stove.
> >
> >
> >
> > Subject of the Aprovechio-meeting will be fan-use in stoves. I think,
> there
> > is a lot of interest to get some "natural-draft-surrogate" to replace or
> > partly replace electrically fans.
> >
> > As I nudged the interest for the Swosthee-stove (Vortex helping for
> > gas-mixing/better-draft),
> >
> >
> >
> > I want to re-introduce the idea for using static-mixers. (Now not in
> > stove-pipes for equal heat dispersion within the cross section, to get
> > better radiant heat use at the tube-wall, my first proposal, but:)
> >
> >
> >
> > There are ceramic static-mixers, which I guess, could be suited to be
> used
> > in burning-chambers of stoves. Does it sheet-metal do as well?
> >
> > Using static mixers, good gas-mixture would be possible with less draft,
> > possibly with natural draft, (when not enough draft: additional
> augmented by
> > other "tricks"?).
> >
> >
> >
> > As Kevin Chrisholm answered to my proposal to use static-mixers, some
> months
> > ago, he was enjoyed, that static-mixers could catch tar in pipes (-his
> > idea-)
> >
> > And his meaning was: static mixers could be constructed relatively
> simple.
> >
> > There was no further discussion in the stoves-list, neither about the
> > geometry of static-mixers nor about the construction/fabrication.
> >
> >
> >
> > Possibly it would be interesting to have some static-mixers by hand, to
> > "hang" them into any stove burning-chamber (-let them warm up-) and have
> a
> > look, if the effect they make, is interesting and promising to make
> > seriously experiments.
> >
> > Even the effect of slowing down the draft must be considered which is
> > sometimes desired but mostly not wanted.
> >
> > Would that be an effect, less important than better mixing of the
> burning
> > gasses?
> >
> >
> >
> >
> >
> > Can we possibly reach a "comfortable stirring" the burning gasses?
> >
> > -Though we know, an electrical fan is most comfortable -
> >
> >
> >
> > Martin
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> > Stoves at listserv.repp.org
> > http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
> >
>
>
>
> ----------------------------------------------------------------
> This message was sent using Illinois State University Webmail.
>
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Mon, 07 Aug 2006 09:28:18 -0500
> From: "Paul S. Anderson" <psanders at ilstu.edu>
> Subject: Re: [Stoves] [Gasification] Heating/thermal usage -    China
>        workshopnotes
> To: english at kingston.net
> Cc: stoves at listserv.repp.org
> Message-ID: <20060807092818.sk5ev15vk08o8gs0 at webmail2.ilstu.edu>
> Content-Type: text/plain;       charset=ISO-8859-1;     format="flowed"
>
> Kevin and all,
>
> Alexis Belonio uses the 2 fuel-chamber approach very well.
>
> Personally, I like to have two fuel canisters that can be switched in and
> out
> for sequentially continuing heat without continuous feed of fuel.  But
> this
> applies only to the small small units where the canisters are small enough
> to
> be manually exchanged.
>
> Finally, the best reply about continuous-feed of a T-LUD could be to have
> some
> other type of gasifier that is continuously operated.  I showed such a
> prototype at the ETHOS 2006 meeting, and I will be bringing an improved
> unit to
> Stove Camp.  It is a "traditional" updraft gasifier (with both pyrolyic
> gasificaton and carbon gasification) with the fire at the bottom and fuel
> coming in at the top.  It is NOT a pyrolytic gasifier, so I refrain from
> calling it a B-LUD, or even worse, a BLUD gasifier.
>
> By the way, a "B-LUD" pyrolytic gasifier does not work.  When the fire
> is lit at
> the bottom of a full pile of fuel, the heat generated does not drive off
> the
> combustible gases (via flaming pyrolysis or retort action) UNTIL AFTER the
> moisture of the fuel pile has been evaporated.  That means that the
> quality of
> the gases would be mainly water vapor at the beginning and then make a
> shift to
> the combustible gases, resulting in an inconsistant supply of usable gases
> for
> the fire.  I learned this from Alexis Belonio during the China
> workshop.  Once
> stated, it seems to be self-evident (unless one forgets about the moisture
> in
> fuels).
>
> I will still be making a third report from the China workshop about
> gasification
> technologies seen and not seen.
>
> Paul
>
> --
> Paul S. Anderson, Ph.D., Geography professor - Emeritus
> Telephone:  USA-309-452-7072 (residence and office)
> Internet site:  www.ilstu.edu/~psanders
> For my gasifier stoves info, go to:
> http://bioenergylists.org/contributors#Paul_Anderson
>
>
> Quoting Alex and Christine English <english at kingston.net>:
>
> > Kevin,
> > One possible way would be to have two or more fuel chambers connected
> > to a single
> > burner. A flap valve would allow the transition from the spent
> > chamber to the newly
> > ignited one.
> > Alex
> >
> >> Dear Ken Et Al
> >>
> >> The T-LUD is indeed a neat piece of equipment, and it certainly works
> well
> >> for a heating application of short duration.
> >>
> >> I must be missing something, but I can't see a simple way to operate a
> T-LUD
> >> stove on a continuous basis. If more fuel is added on the top surface
> of a
> >> T-LUD fuel bed, it then becomes a "Thin Bed Updraft Gasifier", a
> "TBUG".
> >>
> >> It seems to me that the essence of a T-LUD is that there is no fuel
> above
> >> the primary reaction zone, where the fuel is gasified, and that it is
> close
> >> coupled to a secondary zone, where gases are burned to completion.
> >>
> >> Would someone be able to explain how a device that was started up as a
> T-LUD
> >> could be operated on a continuous basis as a T-LUD?
> >>
> >> Thanks.
> >>
> >> Kevin
> >> -----
> >> > Paul,  Stovers and gasification enthusiasts,
> >> >
> >> > Thank you for your report on the proceedings of the ARECOP
> workshop.  Most
> >> > interesting reading.
> >> >
> >> > It appears to me that applications 3,4,5 and 6 (below) could be met
> with a
> >> > T-LUD gasifier of between 20cm and 30 cm diameter.
> >> >
> >> > Might this be a common designed element for these projects that could
> be
> >> > optimised and shared amongst the participants?
> >> >
> >> > regards
> >> >
> >> > Ken Boak
> >> >
> >> > London
> >>
>
> ----------------------------------------------------------------
> This message was sent using Illinois State University Webmail.
>
>
>
>
>
> ------------------------------
>
> Message: 4
> Date: Mon, 7 Aug 2006 07:43:58 -0700
> From: "Mukunda" <hsm at cgpl.iisc.ernet.in>
> Subject: Re: [Stoves] Designs
> To: <stoves at listserv.repp.org>
> Message-ID: <20060807144400.338B12953D at smtpauth.easystreet.com>
> Content-Type: text/plain;       charset="US-ASCII"
>
> Dear Dr. Tom Miles,
>
> Thanks for the e-mail intending to get in touch with me. My own interests
> in stove designs is at least 24 years old. I was spending time intensely
> on stoves till about 1990 and shifted to looking at gasification for
> thermal and electrical applications. This has occupied (in the midst of
> aerospace activities and teaching) most of the time till recently. It has
> got rekindled with the invitation of ARECOP for the training program at
> Kunming. I had occasion to seriously examine the stove developments
> through the Bio Energy Lists website operated and maintained by all of
> you. I must express my appreciation for this effort on maintaining the
> website.
>
> Regarding the Swosthee stove about which you have specific questions -
> About a thousand were built during 1990 - 1884 and field tested. The key
> problem has been the life of the stove. Because the inner metal walls
> experience temperatures of 750 to 1000 C, the hardware lasts only a few
> months. One of the key things that we uncovered in this period was that we
> cannot get higher effioiencies unless the air-to-fuel ratio is close to
> stoichiometric value. It was also clear that any of the stoves that
> utilized free convection process for delivering the air won;t be able to
> maintain the correct air-to-fuel ratio for the duration of the operation
> of the stove. This is the reason that further development in this
> direction was not pursued, We examined the possibility of using a fan to
> deliver the air, some thing that we did in laboratory experiments to
> determine the role of air-to-fuel ratio. Unfprtunately, during 1990 to
> 1994, there was no cheap harware for delivering the air at a fixed flow
> rate. And even after we saw the fixed fuel stove with Dr. thomas Reed in
> 1996 or so, we could not identify for a long time a reasonable source of
> fans. It is only in the last three years that computer fans that are
> really cheap have arrived in the market. This as given life to the reverse
> downdraft stoves all over the place. We have done some serious scientific
> study over the last four years and uncovered features of the stove that
> will give high efficiencies. We have been able to get up to 55 % thermal
> efficiency through various optimization strategies. We are still exploring
> how to get up to values in excess of 60 % particularly because the
> kerosene and gas stoves promise 70 to 75 % efficiency. This has ben our
> aim over the last twentyfour years.
>
> The meeting at Kunming was very interesting. I met with three stove people
> from US working on stoves for long time. What became clear to me at the
> end of the workshop is that very few have clue to the science and
> technology. They are genuine enthusiasts and other people. As soon as they
> see something working, they want to ruch and adopt. For instance, at a
> factory in Kunming, every body saw a beautiful concept on steam injection
> to obtain clean combustion. Almost the next day some wanted to introduce
> it into their designs without (a) really understanding how things work
> or(b)care or sensitivity to intellectual property protection aspects. This
> is a tragedy that stove enthusiasts have to face.
>
> I was told in addition, that a stove performance test protocol was being
> developed at Berkeley with the support of many people. After some
> conversation I learnt that serious sceintists are not involved in this
> activity. A set of data that were presented that showed the amount of fuel
> required to heat 5 L to boil and associated emissions, in my view is very
> faulty as the power level is not a subject of consideration. Th epower
> level makes a seroius differnce to every thing. I also explained in a
> strong way that neither candle nr a furnace can be used for deriving
> cooking heat and I do not know if it went across.
>
> In summary I have concerns on less-than-scientifically correct input going
> into the stove design aspects. I have just expressed it to you here.
>
> We will continue our efforts to produce a high efficiency clean burning
> continuous feed biomass stove in coming times.
>
> I will be happy to interact with you or others on any scientific aspects.
> The paper that you enquired is available on a web site for downloading. i
> shall intimate you the address on Monday/Tuesday.
>
> I am sorry for the long mail and Thanks for the inspiration to express my
> thoughts. - H S` Mukunda
>
>
>
>
>
>
> > Paul,
> >
> > If you have a current email address for Dr. Mukunda could you invite him
> > to discuss the Swothsee stove? We have been asking what the actual use
> > of the stove has been and whether it would be a good candidate for a
> > FAN. We have also been discussing vortex combustion in stoves (Vesto,
> > Maputo,
> > V-Sidewinder, Woodgas) which should still be a topic of interest to him.
> > We have many questions.
> > See
> >
>
> http://listserv.repp.org/pipermail/stoves_listserv.repp.org/2006-August/date
> > .html
> >
> > We are also looking for a copy of his paper:
> > H.S. Mukunda, U. Shrinivasa, S. Dasappa, S.B. Sunil Kumar, SWOSTHEE -
> > Portable Single Pan Wood Stoves of High Efficiency for Domestic use,
> > Sadhana, J.I.A.Sc, 13, pp. 237-270, 1988.
> >
> > So far we have only some photos from Auke Koopmans (1998) and a
> > BUN-India report:
> > http://bioenergylists.org/en/swosthee
> >
> > Thanks,
> >
> > Tom Miles
> > tmiles at trmiles.com
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > -----Original Message-----
> > From: stoves-bounces at listserv.repp.org
> > [mailto:stoves-bounces at listserv.repp.org] On Behalf Of Paul S. Anderson
> > Sent: Saturday, August 05, 2006 6:45 AM
> > To: Kevin Chisholm
> > Cc: stoves at listserv.repp.org
> > Subject: Re: [Stoves] Designs
> >
> > Ian, Steve, Kevin and all,
> >
> > The steps that Kevin has enumerated below are basicially the same
> > approach that Dr. Makunda used at the ARECOP workshop in China last
> > week.  I will post more about it soon, but I want to reinforce what
> > Kevin wrote.  Analyze the application, then find the solution(s), then
> > make the stoves/heaters. Sort of like computer programming:  application
> > defines the system-analysis which defines the steps of programming to
> > accomplish the task.
> >
> > It certainly helps if you have an already operational application and
> > are seeking an alternative source of heat.  That was the case in 7 of
> > the 8 projects proposed at the ARECOP meeting.
> >
> > Paul
> > --
> > Paul S. Anderson, Ph.D., Geography professor - Emeritus
> > Telephone:  USA-309-452-7072 (residence and office) Internet site:
> > www.ilstu.edu/~psanders For my gasifier stoves info, go to:
> > http://bioenergylists.org/contributors#Paul_Anderson
> >
> > Quoting Kevin Chisholm <kchisholm at ca.inter.net>:
> >
> >> Dear Ian
> >>
> >> ...del...
> >>
> >> Rather than starting with a search for stoves designs and evaluating
> >> whether or not they are appropriate, may I suggest that you "start at
> >> the
> > other end"
> >> and define the problem and opportunity? Once you have the problem
> >> described, it is much easier to recognize or design a solution.
> >>
> >> 1: What production rate do you require, in terms of kG of dried Kava
> >> product per hour?
> >>
> >> 2: What is the moisture content range of the raw kava?
> >>
> >> 3: What is the desired moisture content range of the finished kava?
> > ....snipped....
> >
> >
> > ----------------------------------------------------------------
> > This message was sent using Illinois State University Webmail.
> >
> >
> >
> > _______________________________________________
> > Stoves mailing list
> > Stoves at listserv.repp.org
> > http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
>
>
>
>
>
>
>
>
>
> ------------------------------
>
> Message: 5
> Date: Mon, 07 Aug 2006 09:51:21 -0500
> From: psanders at ilstu.edu
> Subject: Re: [Stoves] [Gasification] Heating/thermal usage -    China
>        workshopnotes
> To: David Fulford <d.j.fulford at reading.ac.uk>
> Cc: ARECOP - Listserve <arecop at yahoogroups.com>,        GASIFICATION -
>        Listserve <GASIFICATION at listserv.repp.org>,     STOVES - Listserve
>        <STOVES at LISTSERV.REPP.ORG>
> Message-ID: <20060807095121.zaw9pqamm8kcgkkg at webmail2.ilstu.edu>
> Content-Type: text/plain;       charset=ISO-8859-1;     format="flowed"
>
> David and all,
>
> After a preliminary reading of the website, I comment:
>
> 1.  They say "syngas", but isn't that when only oxygen is used?  If they
> keep
> their operating costs low and are not looking for real high temperatures
> (to
> avoid clinker creation), they probably run mostly with air, and that would
> yield "producer gas" with the high percentage of N2 nitrogen in the
> flue gases.
>
> 2.  Being basically an up-draft gasifier, we expect "char-making inside
> the
> gasifier and tar-burning in the flue gases".  Close-coupled combustion
> would be
> quite important, and it is highly unlikely that this unit could yield
> gases for
> operating IC engines.
>
> 3.  I was wondering about the size of the unit.  A click on the "Product
> Development and Test Plant" button shows a unit 2 storeys high.  This is a
> big
> plant, and is probably not "down-size-able" to serve the needs of
> cookstoves or
> even institutional cookers.
>
> I like it and I am sure it has a niche, even a large niche.  But not with
> cooking.
>
> Paul
>
> Quoting David Fulford <d.j.fulford at reading.ac.uk>:
>
> > Ken and others,
> >
> > Ken, you have just almost described the technology about which Roger
> > Samson was asking on the gasification list; the Nexterra gasifier:
> > http://www.nexterra.ca/technology/index.cfm
> >
> > It is an updraft gasifier that keeps a fixed level of fuel above the
> > combustion zone. It claims to produce clean gas, but only suggests
> > that it is used for heating, not for running engines, so I am not
> > sure about the claim.
> >
> > David
> >
> > At 23:07 06/08/2006 +0100, Ken Boak wrote:
> >> Kevin & List,
> >>
> >> It's quite simple (easier said than done perhaps) , you have to provide
> a
> >> mechanical means that replenishes the fuel from the underneath or side
> at a
> >> rate that matches the burn down rate.
> >>
> >> Think of it like a rocket stove but with an auger that feeds the fuel
> in
> >> from the side, such that the combustion and pyrolysis zones remain
> almost
> >> stationary towards the top of the gasifier.
> >>
> >>
> >> Ken
>
>
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> End of Stoves Digest, Vol 2, Issue 11
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>