Philip, Thanks for the reference. It looks like the CarboConsult gasifier from South Africa. http://www.carboconsult.com/
http://www.erc.uct.ac.za/jesa/jesa-currentabstracts.htm Volume 22 No 4: December 2011 The technical pre-feasibility to use briquettes made from wood and agricultural waste for gasification in a downdraft gasifier for electricity generation Pholoso Malatji, Ntshengedzeni Sampson Mamphweli and Martina Meincken Biomass can be converted to energy through various thermochemical and biological processes. Gasification is one of the thermochemical processes that has recently gained popularity, because it achieves higher conversion efficiencies than, for example, incinerators, boilers or furnaces. Fixed-bed downdraft gasifiers are preferred for electricity generation, because they produce very little tar, but on the other hand, they are limited with regard to biomass properties, such as particle size, bulk density and moisture content. Biomass material with a heterogeneous size is usually processed into pellets or briquettes, which have to be mechanically strong enough to be handled. Cohesive strength is provided by residual moisture and lignin present in most biomass. However, the briquetting process becomes more complicated if one wants to add agricultural waste products that do not necessarily contain lignin as binders. The aim of this work was to process wood chips, grape skins and chicken litter into briquettes that are mechanically stable and have a sufficiently high energy content, as well as adequate bulk density for gasification. The performance of these briquettes in a downdraft gasifier was simulated with a program developed for wood, which was modified to optimise the briquette yield. The results showed a gasification performance comparable to solid pine wood, implying that the blended briquettes could be used as fuel for a downdraft biomass gasifier. Unfortunately, the briquettes proved too instable to experimentally verify the performance in a gasifier. This paper describes the properties of the briquettes as well as the gasification simulation results. Tom -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Philip Lloyd Sent: Tuesday, January 24, 2012 11:48 PM To: [email protected] Subject: Re: [Stoves] Stoves Digest, Vol 17, Issue 35 The latest edition of Journal of Energy in Southern Africa, Vol 22 No4 (November 2011) has an article on the use of biowaste briquettes in a downdraft gasifier for electricity production (pp 2-7) Prof Philip Lloyd Energy Institute Cape Peninsula University of Technology PO Box 652, Cape Town 8000 Tel: +27 21 460 4216 Fax: +27 21 460 3828 Cell: 083 441 5247 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: 24 January 2012 07:45 To: [email protected] Subject: Stoves Digest, Vol 17, Issue 35 Send Stoves mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists .org or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of Stoves digest..." Today's Topics: 1. Re: The upside of Down feed (Alex English) 2. Re: The upside of Down feed ([email protected]) 3. Re: [Ethos] ETHOS schedule (Choppalli Venkata Krishna) 4. Re: The upside of Down feed (Crispin Pemberton-Pigott) 5. Re: [Ethos] ETHOS schedule (Otto Formo) 6. Re: [Ethos] ETHOS schedule (Alex English) 7. Re: [Ethos] ETHOS schedule (Tom Miles) 8. Total Energy Wiki launched (Crispin Pemberton-Pigott) 9. Re: The upside of Down feed ([email protected]) 10. Re: The upside of Down feed (Crispin Pemberton-Pigott) ---------------------------------------------------------------------- Message: 1 Date: Mon, 23 Jan 2012 20:45:36 -0500 From: Alex English <[email protected]> To: Discussion of biomass cooking stoves <[email protected]> Subject: Re: [Stoves] The upside of Down feed Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Dear Crispin, On 22/01/2012 10:36 PM, Crispin Pemberton-Pigott wrote: > > Dear Alex > > This is interesting news. The grate looks great, and if there is a > pile of char that is maintained in front, we must conspire to burn it. > Not so fast. I rather like the idea of a naturally formed biochar venturi:) > > To review, it is a crossdraft fire with all the advantages inherent in > it: refuellable and lots of room for flames. > > If the char builds up in front of the hopper but self-limits (i.e. > burns away) then it has to be eaten by the passing flame and available > O2. That being so, I see a couple of options. One is to admit air > through some small holes (1.6, 2.0mm) drilled under the early part of > the pile (on the grate side of the pile). That will bleed air under > the char which is a good way to burn it. Another is to change the > shape of the pipe in that area to allow ash to drop. I presume at the > moment the ash is blown into the larger chamber of the stove. > I see the odd spark or glowing particle fly into the stove. This is what you see in most pellet stoves which do tend to have relatively low PM emissions. In part that has to do with the way the size of the particles in the pellet ('sawdust' is really tiny wood chips) and how they tend to hold together. When the hopper does runs out of fuel the added air flow literally blows whole charred pellets into the stove. A chimney draft is nothing to sneeze at, so to speak. > > It is highly likely you have a fairly large PM10 number compared with > the same fuel burned in a pile in that larger chamber because of > lofted ash. > > I am really pleased to hear that the flow is so reliable. I have some > really short fat pellets here which are probably going to feed well > because they are nearly marbles. Probably made with one of those > trochoid, concentric-ring pellet formers. > > As for the fire rising into the hopper, that is not going to happen if > the air velocity is high enough. Conditions we have observed it is > when the velocity is quite low. If the heat is enough, a rising > current of heated air and gas circulates in the fuel immediately above > the burning layer and the fire works its way up. That can only happen > if a) there is some air (especially from above) or b) the fuel is > volatile enough to run an air-free charring burn in the present of > enough heat. > > The advantage of coal, even with a highly volatiles one like the > lignite from Nalaikh mine, it is still less volatile than wood. The > talk of torrefied pellets intrigues me for that reason. It is more > likely to behave like slow roasting coal. Very controllable. There are > small coal pellets, say 16mm diameter which might feed well too. > > Is there any reason you can think of that the hopper, feed tube and > burning chamber should be round? > No. > > If you pass by the house I can show you a stove body that your burner > will directly attach to with several novel features. It won't be shown > until March and sort of solves the 'rest of a stove' for you. I am > pretty sure you will like it. It /might/ address the PM10 issue, or > not, and solves the heat extraction issues for cooking and heating. > > I have some Kanthal wire here which we are recommending for grate > material. It will work well for you and will hardly get hot at all. If > some small bits of fuel drop through (being ahead of the grate) a > pocket can be provided underneath to let them smoulder, feeding CO and > C and H2 into the beginning of the fire. No problem. > > The arrangement is made similarly on the SeTAR BLDD5 with the > smoulderings fed into the flaming portion of the pipe. The reason I > mention a wire grate is it is cheap and easy to make. But like the > layered flats too. It should be possible to punch that in a single > stroke with the right tool. > > How deep is the fuel in the hopper? > 40 cm. I have materials to go up to 100cm, and I could take it up to near the ceiling with some stove pipe, though I might have to counter balance the stove:) > I tried a number of things with hopper shape and decided there is a > general rule about bridging which is the following: if the hopper > tapers inwards the point of burning, there is an upper limit to the > height of the fuel for each degree of narrowing. I tried shoulders too > and they are OK further up (for example, within 1 hopper width of the > top of the fuel pile). On all cases, if the fuel is compressed by > pushing down on it or by stacking lots of fuel up, bridging occurs > just above the beginning of the taper. > These pellets are highly resistant to bridging. On the other hand I have seen chips defy gravity:) > > The solution is agitation or a non-tapering hopper bottom. > > This is bound to be affected by the surface smoothness of the fuel > particle. If the pellets are shiny and hard that has to be a help > avoid bridging, right? I am impressed that you are able to keep it > feeding so well with such a significant narrowing. > It is difficult to measure but the pellet flow is in fact air (wind) assisted. However they are more bullet than sail. Small dry wood chips are sails and if they make it down through the hopper, they blow right out of the tube. > > To you think it is necessary to tilt the flame tube downwards at all? > If the char pushed ahead it would be burned by the continuous heat of > the flame. Using wood, I can report that I have seen flames reaching > more than 24 inches along the tube so you may get better combustion > efficiency by lengthening the one you have. > Yes, a view of the flame is useful for understanding the process but is not ideal for combustion. > > Thanks for an interesting (tiny) burner idea. If you bring it here I > have some 5mm switchgrass pellets I have had difficulty burning it > anything yet. Maybe... > I suspect the ash would bung it up, but maybe...not. Alex > > Crispin > > *From:*[email protected] > [mailto:[email protected]] *On Behalf Of *Alex > English > *Sent:* Sunday, January 22, 2012 7:02 PM > *To:* Discussion of biomass cooking stoves > *Subject:* Re: [Stoves] The upside of Down feed > > Dear Crispin, > The pellets are 6mm dia. 1-2.5 cm long. The hole is 5cm in diameter. I > tried a few chips to block the hole. It usually took more than one to > stop it, and put out the fire. There isn't much evidence of the fire > mving up into the hopper. The attached picture shows the position of > grate in relation to the hopper. It is adjustable. A mount of glowing > charred pellets form in the bottom half of the tube (6.2 cm ID pipe) > out in front of the grate. This seems to be self limiting, at least > over the five hours it ran today. > > I ran it with a second hopper tube such that the air flowed outside > the inner 14cm diameter hopper (with lid) and inside the outer15.5cm > diameter hopper. The air has to pas through pellets in the cone > portion only. > > Shutting off the grate air does reduce the burn rate by as much as > half, but that is a guess and I am unsure if it works for hours. > > but wood pellets are cheating... > > next, a complete redesign for chips... > > courting failure.... > Alex > > > > > > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > [email protected] > > 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://www.bioenergylists.org/ > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120123/107024dc/attachment-0001.html> ------------------------------ Message: 2 Date: Tue, 24 Jan 2012 04:38:55 +0000 (UTC) From: [email protected] To: Discussion of biomass cooking stoves <[email protected]>, Alex English <[email protected]> Subject: Re: [Stoves] The upside of Down feed Message-ID: <761568507.148960.1327379935868.javamail.r...@sz0133a.emeryville.ca.mail.com cast.net> Content-Type: text/plain; charset="utf-8" Alex and list: My interest is in the first several lines , which read: Crispin: "This is interesting news. The grate looks great, and if there is a pile of char that is maintained in front, we must conspire to burn it." Alex: "Not so fast. I rather like the idea of a naturally formed biochar venturi:) " RWL: I have totally missed the possibility of a char output in your design. I can't even see a Venturi possibility.. Can you explain a bit more on how that can be accomplished? Have you accomplished any char preservation yet? Thanks. Ron ----- Original Message ----- From: "Alex English" <[email protected]> To: "Discussion of biomass cooking stoves" <[email protected]> Sent: Monday, January 23, 2012 6:45:36 PM Subject: Re: [Stoves] The upside of Down feed Dear Crispin, On 22/01/2012 10:36 PM, Crispin Pemberton-Pigott wrote: Dear Alex This is interesting news. The grate looks great, and if there is a pile of char that is maintained in front, we must conspire to burn it. Not so fast. I rather like the idea of a naturally formed biochar venturi:) <blockquote> <snip remainder> </blockquote> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120124/c357dc84/attachment-0001.html> ------------------------------ Message: 3 Date: 24 Jan 2012 05:01:22 -0000 From: "Choppalli Venkata Krishna" <[email protected]> To: "[email protected]" <[email protected]> Subject: Re: [Stoves] [Ethos] ETHOS schedule Message-ID: <1327332515.S.6194.18424.H.TlBhdWwgUy5BbmRlcnNvbgBSZTogW1N0b3Zlc10gW0V0aG9zX sbfvehpuybzy2hlzhvszq__.f4-235-187.old.1327381282.9...@webmail.rediffmail.co m> Content-Type: text/plain; charset="utf-8" Dear Dr.TLUD Thanks for disseminating the details. May your tribe grow. -C.V.KrishnaFrom: "Paul S. Anderson" <[email protected]>Sent: Mon, 23 Jan 2012 20:58:35 To: [email protected], Stoves <[email protected]>Subject: Re: [Stoves] [Ethos] ETHOS scheduleDear Mark, Angie and all,For my presentation Saturday evening (are you calling it Keynote?), please use this title:Micro-gasifier Stoves for Meeting the 2020 Goals of the Global Alliance for Clean Cookstoves(I assure you that it will have food for thought and discussion and action!!)And will ETHOS please allow that to be a "public presentation" so that people who are not registered for the conference can attend? I think this could assist ETHOS to reach out to others in the community and to students and faculty of the university that hosts us.ALSO, could the ETHOS program please make reference to the Friday MORNING activity being presented by the BEF. The info is below, and is also found at my website: www.drtlud.com Thanks.TLUD Workshop Offered Prior to ETHOS ConferenceOn Friday, 27 January 2012, the Biomass Energy Foundation (BEF) will be offering a workshop on the technical and practical concepts of its micro-gasification units. Dr. Paul S. Anderson (aka ?Dr TLUD?) will provide an overview of the science and technology of the Top-Lit UpDraft (TLUD) stove and its applications in meeting the cooking needs of local communities around the globe. He will be assisted by Bob Fairchild, Christa Roth, and Kathy Nafie .This event is hosted by Hydrovolts, Inc., 210 S Hudson St, #330 Seattle, WA 98134. Cost is $25 per person, and RSVP can be made by contacting Kathy Nafie at [email protected] by Wednesay, 25 January 2012. Questions can be directed to Kathy Nafie at 303-570-6868 .**************************Will see you all in Seattle!!!Paul-- Paul S. Anderson, PhDKnown to some as: Dr. TLUD Doc ProfessorPhone (USA): 309-452-7072 SKYPE: paultlud Email: [email protected]/de/dokumente/giz2011-en-micro-gasification.pdf (Best ref.)>> On Sun, Jan 22, 2012 at 7:19 PM, Bryden, Kenneth [M E] <[email protected]>> wrote:>>> All,>>>> I'm putting the final touches on the schedule and will have it out to>> everyone tomorrow. A couple of items>>>> - if you have time constraints on your talk (e.g., late arrival or early>> departure) Just let me know and I'll get you scheduled at the right time.>>>> - Registration will start 4 pm on Friday at the hotel.>>>> - We'll have the usual slide show on Friday evening at 7 pm at the hotel.>> Bring your slides, we want to see where you've been and what you are doing!>>>> - There will be no meal provided on Friday evening - this is different>> than other years. However feel free to bring food back to our room at the>> hotel or call for delivery, etc.>>>> Thanks and see you there!>> Mark>> _______________________________________________>> Ethos mailing list>> [email protected]>> http://cannon-mail.vrac.iastate.edu/mailman/listinfo/ethos>>>------ ----------------------------------------------------------This message was sent using Illinois State University RedbirdMail_______________________________________________Stoves mailing listto Send a Message to the list, use the email [email protected] UNSUBSCRIBE or Change your List Settings use the web pagehttp://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergyl ists.orgfor more Biomass Cooking Stoves, News and Information see our web site:http://www.bioenergylists.org/ -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120124/a679a87c/attachment-0001.html> ------------------------------ Message: 4 Date: Tue, 24 Jan 2012 02:58:54 -0500 From: "Crispin Pemberton-Pigott" <[email protected]> To: "'Discussion of biomass cooking stoves'" <[email protected]> Subject: Re: [Stoves] The upside of Down feed Message-ID: <[email protected]> Content-Type: text/plain; charset="us-ascii" Dear Alex >>This is interesting news. The grate looks great, and if there is a >>pile of char that is maintained in front, we must conspire to burn it. >Not so fast. I rather like the idea of a naturally formed biochar venturi:) I agree and want to see it in action - it might have a good mixing contribution to make. >>I presume at the moment the ash is blown into the larger chamber of >>the stove. >I see the odd spark or glowing particle fly into the stove. I noticed that on the video. The flames looked like they needed more tube length, actually. You can see them chilling as they enter they open space. >This is what you see in most pellet stoves which do tend to have >relatively low PM emissions. In part that has to do with the way the size of the particles in the pellet ('sawdust' is really tiny wood chips) and how they tend to hold together. When the hopper does runs out of fuel the added air flow literally blows whole charred pellets into the stove. A chimney draft is nothing to sneeze at, so to speak. That is good news. How about turning the tube supplying air through the grate upwards? >>Is there any reason you can think of that the hopper, feed tube and burning chamber should be round? >No. OK. Might assist in suppressing CO sneakage in the corners. >>How deep is the fuel in the hopper? >40 cm. I have materials to go up to 100cm, and I could take it up to >near the ceiling with some stove pipe, though I might have to counter balance the stove:) Interested to know if it will feed that whole tube. If so, it could have a large hopper with a low slope. If you want, bring material and I will cut and weld it for you. >These pellets are highly resistant to bridging. On the other hand I >have seen chips defy gravity:) Are they noticeably slippery to the touch? >It is difficult to measure but the pellet flow is in fact air (wind) assisted. However they are more bullet than sail. Small dry wood chips are sails and if they make it down through the hopper, they blow right out of the tube. There are just so many advantages to using pellets. >>Using wood, I can report that I have seen flames reaching more than 24 inches along the tube so you may get better combustion efficiency by lengthening the one you have. >Yes, a view of the flame is useful for understanding the process but is >not ideal for combustion. It seems from the look and the layout, that adding more flame tube would/could bring CO down to zero, or at least undetectable. >>Thanks for an interesting (tiny) burner idea. If you bring it here I >>have some 5mm switchgrass pellets I have had difficulty burning it anything yet. Maybe. >I suspect the ash would bung it up, but maybe...not. Ask is not the problem that I see, it is that it is so dense it will not breathe properly. TLUD's it chokes immediately. It would need a fan to get much air through it. But if dropped from above it would certainly flow, if it is dry. I would like to try it. Ask Roger Samson to drop off some different sized pellets when he next passes by your place, which is quite often. Thanks Crispin -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120124/489cb2b4/attachment-0001.html> ------------------------------ Message: 5 Date: Tue, 24 Jan 2012 11:13:28 +0100 (MET) From: Otto Formo <[email protected]> To: "Paul S. Anderson" <[email protected]>, <[email protected]>, Stoves <[email protected]> Subject: Re: [Stoves] [Ethos] ETHOS schedule Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Dear Paul, Thanks for the infomation and your "public presentation" efforts at the ETHOS conference in Seatle. Promoting gasfier stoves are still very much needed for the low income households of the developing World. Will you also be attending the conference in Amsterdam? Best wishes Otto > From: Paul S. Anderson [[email protected]] > Sent: 2012-01-23 16:27:30 MET > To: [email protected], Stoves [[email protected]] > Subject: Re: [Stoves] [Ethos] ETHOS schedule > > Dear Mark, Angie and all, > > For my presentation Saturday evening (are you calling it Keynote?), > please use this title: > > Micro-gasifier Stoves for Meeting the 2020 Goals of the Global > Alliance for Clean Cookstoves > > (I assure you that it will have food for thought and discussion and action!!) > > And will ETHOS please allow that to be a "public presentation" so that > people who are not registered for the conference can attend? I think > this could assist ETHOS to reach out to others in the community and to > students and faculty of the university that hosts us. > > ALSO, could the ETHOS program please make reference to the Friday > MORNING activity being presented by the BEF. The info is below, and > is also found at my website: www.drtlud.com Thanks. > > TLUD Workshop Offered Prior to ETHOS Conference > > On Friday, 27 January 2012, the Biomass Energy Foundation (BEF) will > be offering a workshop on the technical and practical concepts of its > micro-gasification units. Dr. Paul S. Anderson (aka ?Dr TLUD?) will > provide an overview of the science and technology of the Top-Lit > UpDraft (TLUD) stove and its applications in meeting the cooking needs > of local communities around the globe. He will be assisted by Bob > Fairchild, Christa Roth, and Kathy Nafie . > > This event is hosted by Hydrovolts, Inc., 210 S Hudson St, #330 > Seattle, WA 98134. Cost is $25 per person, and RSVP can be made by > contacting Kathy Nafie at [email protected] by Wednesay, > 25 January 2012. Questions can be directed to Kathy Nafie at > 303-570-6868 . > > ************************** > Will see you all in Seattle!!! > > Paul > -- > Paul S. Anderson, PhD > Known to some as: Dr. TLUD Doc Professor > Phone (USA): 309-452-7072 SKYPE: paultlud Email: [email protected] > www.gtz.de/de/dokumente/giz2011-en-micro-gasification.pdf (Best ref.) > > > > > On Sun, Jan 22, 2012 at 7:19 PM, Bryden, Kenneth [M E] <[email protected] > >> wrote: > > > >> All, > >> > >> I'm putting the final touches on the schedule and will have it out > >> to everyone tomorrow. A couple of items > >> > >> - if you have time constraints on your talk (e.g., late arrival or early > >> departure) Just let me know and I'll get you scheduled at the right time. > >> > >> - Registration will start 4 pm on Friday at the hotel. > >> > >> - We'll have the usual slide show on Friday evening at 7 pm at the hotel. > >> Bring your slides, we want to see where you've been and what you > >> are doing! > >> > >> - There will be no meal provided on Friday evening - this is > >> different than other years. However feel free to bring food back to > >> our room at the > >> hotel or call for delivery, etc. > >> > >> Thanks and see you there! > >> Mark > >> _______________________________________________ > >> Ethos mailing list > >> [email protected] > >> http://cannon-mail.vrac.iastate.edu/mailman/listinfo/ethos > >> > > > > > ---------------------------------------------------------------- > This message was sent using Illinois State University RedbirdMail > > > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > [email protected] > > 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://www.bioenergylists.org/ > ------------------------------ Message: 6 Date: Tue, 24 Jan 2012 06:31:41 -0500 From: Alex English <[email protected]> To: Discussion of biomass cooking stoves <[email protected]> Subject: Re: [Stoves] [Ethos] ETHOS schedule Message-ID: <[email protected]> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Perhaps its time for a name change, 'Chief TLUD' Alex :) On 24/01/2012 12:01 AM, Choppalli Venkata Krishna wrote: > Dear Dr.TLUD > Thanks for disseminating the details. May your tribe grow. > -C.V.Krishna > > > ------------------------------ Message: 7 Date: Tue, 24 Jan 2012 08:12:44 -0800 From: "Tom Miles" <[email protected]> To: "'Discussion of biomass cooking stoves'" <[email protected]> Subject: Re: [Stoves] [Ethos] ETHOS schedule Message-ID: <[email protected]> Content-Type: text/plain; charset="us-ascii" "Chief TLUD" would surely lead to a TLUD Casino. Tom -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Alex English Sent: Tuesday, January 24, 2012 3:32 AM To: Discussion of biomass cooking stoves Subject: Re: [Stoves] [Ethos] ETHOS schedule Perhaps its time for a name change, 'Chief TLUD' Alex :) On 24/01/2012 12:01 AM, Choppalli Venkata Krishna wrote: > Dear Dr.TLUD > Thanks for disseminating the details. May your tribe grow. > -C.V.Krishna > > > _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] 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://www.bioenergylists.org/ ------------------------------ Message: 8 Date: Tue, 24 Jan 2012 12:21:42 -0500 From: "Crispin Pemberton-Pigott" <[email protected]> To: "Stoves" <[email protected]> Subject: [Stoves] Total Energy Wiki launched Message-ID: <[email protected]> Content-Type: text/plain; charset="utf-8" From: energypedia News [mailto:[email protected]] Sent: Tuesday, January 24, 2012 9:38 AM Tim Raabe published a new blog article: Total Energy Wiki launched International NGO Practical Action <http://practicalaction.org> with support from GIZ has set up the <https://energypedia.info/index.php/Totalenergywiki> Total Energy Wiki (within energypedia) as an online data collection system enabling people and organizations to participate in and contribute to collecting data on energy access in a new way. It is a grassroots, crowd-sourced way of collecting data which could complement existing data collection systems, and provide a broader picture of how energy services are made available to and used by poor people. <https://energypedia.info/index.php/File:Tew.JPG> Tew.JPG Go to Article <https://energypedia.info/index.php/Blog:News/Total_Energy_Wiki_launched> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120124/8fd8d1f4/attachment-0001.html> ------------------------------ Message: 9 Date: Tue, 24 Jan 2012 17:35:29 +0000 (UTC) From: [email protected] To: Discussion of biomass cooking stoves <[email protected]>, Alex English <[email protected]> Cc: Agua Das <[email protected]> Subject: Re: [Stoves] The upside of Down feed Message-ID: <1863643859.168759.1327426529073.javamail.r...@sz0133a.emeryville.ca.mail.co mcast.net> Content-Type: text/plain; charset="utf-8" Alex and list: This is to further explore the idea of char production in your device (which we should call??). In the exchange below, I think I have to side with Crispin - is not the fuel essentially all combusted? Of course it is the usual two-step combustion - with pyrolysis first leaving a pile of char - which is then itself more slowly combusted? As the char disappears, more pellets are able to fall down. You seem to have established stable rates of pellet and air flows such that the pyrolysis zone is unable to travel up into the hopper. The Venturi effect you mentioned is one drawing both pellets and air down from the hopper - yes? (When I wrote yesterday I was fixated on char movement.) My reason for still pursuing the char production possibility is that your geometry seems very similar to the Dasifier (concept of Agua Das - being ccd). Das tells me he can produce char. Somehow your grate has to be replaced by one that allows char to fall through?? Is there any alternative then to an auger? Might it make sense to replace the tall chimney in some circumstances with a blower? (To lower first costs - allowing a much shorter chimney?) Is this development related at all to backup heating of your greenhouse? Or manly intended for home heating? Any applicability to cooking? Ron ----- Original Message ----- From: [email protected] To: "Discussion of biomass cooking stoves" <[email protected]>, "Alex English" <[email protected]> Sent: Monday, January 23, 2012 9:38:55 PM Subject: Re: [Stoves] The upside of Down feed Alex and list: My interest is in the first several lines, which read: Crispin: "This is interesting news. The grate looks great, and if there is a pile of char that is maintained in front, we must conspire to burn it." Alex: "Not so fast. I rather like the idea of a naturally formed biochar venturi:)" RWL: I have totally missed the possibility of a char output in your design. I can't even see a Venturi possibility.. Can you explain a bit more on how that can be accomplished? Have you accomplished any char preservation yet? Thanks. Ron ----- Original Message ----- From: "Alex English" <[email protected]> To: "Discussion of biomass cooking stoves" <[email protected]> Sent: Monday, January 23, 2012 6:45:36 PM Subject: Re: [Stoves] The upside of Down feed Dear Crispin, On 22/01/2012 10:36 PM, Crispin Pemberton-Pigott wrote: Dear Alex This is interesting news. The grate looks great, and if there is a pile of char that is maintained in front, we must conspire to burn it. Not so fast. I rather like the idea of a naturally formed biochar venturi:) <blockquote> <snip remainder> </blockquote> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/a ttachments/20120124/57a1d739/attachment-0001.html> ------------------------------ Message: 10 Date: Tue, 24 Jan 2012 12:44:28 -0500 From: "Crispin Pemberton-Pigott" <[email protected]> To: "'Discussion of biomass cooking stoves'" <[email protected]>, "'Alex English'" <[email protected]> Cc: 'Agua Das' <[email protected]> Subject: Re: [Stoves] The upside of Down feed Message-ID: <[email protected]> Content-Type: text/plain; charset="utf-8" Dear Friends Agua Das is using an air aspirator for draft ? a concept I strongly endorse for use inside a home because it puts the whole system under negative pressure, basically eliminating the possibility of CO leaking into the room. I think a significant difference is that Agua has a controlled secondary air supply and Alex?s simple version looks like it draws all air through the grate, or through the fuel at the grate. With a predictable fuel there is no problem doing this once the geometry is set (for that fuel). Regards Crispin ++++++++ Alex and list: This is to further explore the idea of char production in your device (which we should call??). In the exchange below, I think I have to side with Crispin - is not the fuel essentially all combusted? Of course it is the usual two-step combustion - with pyrolysis first leaving a pile of char - which is then itself more slowly combusted? As the char disappears, more pellets are able to fall down. You seem to have established stable rates of pellet and air flows such that the pyrolysis zone is unable to travel up into the hopper. The Venturi effect you mentioned is one drawing both pellets and air down from the hopper - yes? (When I wrote yesterday I was fixated on char movement.) My reason for still pursuing the char production possibility is that your geometry seems very similar to the Dasifier (concept of Agua Das - being ccd). Das tells me he can produce char. Somehow your grate has to be replaced by one that allows char to fall through?? Is there any alternative then to an auger? Might it make sense to replace the tall chimney in some circumstances with a blower? (To lower first costs - allowing a much shorter chimney?) Is this development related at all to backup heating of your greenhouse? Or manly intended for home heating? Any applicability to cooking? Ron -------------- next part -------------- An HTML attachment was scrubbed... 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