Hi Mr Kavre, Thanks a lot for the info.
What would you say would be the air velocity for the Prakti Leo stove (2 pot chimney) or any similar kind of 2 pot stove( natural convection) Cheers Sarbagya Tuladhar Sent from my iPhone On 21/03/2012, at 2:42 PM, Anand Karve <[email protected]> wrote: > Dear Mr. Tuladhar, > One can generalise that the air entering the stove goes out through the pot > hole and the chimney. There are stoves in which the volume of air entering > the stove through the grate is reduced while that of the scondary air > entering the stove through the firemouth is enhanced. There are also stoves > in which the pot sits flush on the stove, so that all the outgoing air has to > pass through chimney. But there are also chimneyless stoves. Thus, the amount > of air entering or leaving the stove through various inlets and outlets and > their velocities depend very much on the stove design. > Yours > A.D.Karve > > > > On Mon, Mar 19, 2012 at 1:34 PM, Sarbagya Tuladhar <[email protected]> > wrote: > Hi Stovers, > > Just veering off the topic of dung for a moment, has anyone got any kind of > data on the air velocity for natural convection stoves.. Any kind of data > would be useful ? Could be air velocity at the cooktops or the chimney ? I > suppose the max velocity would be at the chimney area due to the chimney > effect (draft).. > > Cheers > > Sarbagya > > On Mon, Mar 19, 2012 at 4:27 PM, Sarbagya Tuladhar <[email protected]> > wrote: > Interesting indeed. However stink is not as much a problem when dried > completely. Even with the dung briquettes, the stink is no more when dried. > However, the case with pyrolyzing the dung and releasing the hamrful toxins, > if the smoke and aroma can be removed then thats certainly worth a try. Any > more info on Francis of Kenya ? > > Cheers > Sarbagya > > On Mon, Mar 19, 2012 at 12:16 PM, Richard Stanley <[email protected]> > wrote: > This is interesting. Out in Miumbuni village, about 2hrs east of Nairobi and > another hr off the Mombassa road, is a one Francis Kavita who has been > working with the Masaai in developing cow dung based briquettes that do not > stink: He has developed same with elephant dung in south Eastern Kenya (near > Tasavo) and is now breaking ground with camel dung based blends for use in > the refugee camps in Somalia. He has tested them and he says the work well > without smoke or aroma. > He has no numbers for > what he ahas done but is still far more experience than anyone else, > including all the Phd students we know of. If he says it will work I believe > it: > > We started him in briquette making in 1999, and trained he and his wife Mary > in 2007 as trainers and they have been all over east Africa training > others–on their own–, ever since. The problem is not that it works or does > not work, Its a case of what we need to be convinced of it. The Phd study or > Francis' experience. After all he only has a 4th grade education. > > Alternatively, can we evolve a more balanced discovery model with due respect > for the unique contributions of knowledge and experience that both have to > offer. > > Richard Stanley > www.legacyfound > ========== > > > > On Mar 16, 2012, at 9:26 PM, SARBAGYA TULADHAR wrote: > > Hi Stovers, > > I am undertaking my uni graduate project on the Use of CFD for the study of > heat transfer and convection in a Dung Burning Cookstove. With this project, > a heat transfer and convection analysis would be carried out using > Computational Fluid Dynamics (CFD) for the optimization of dung burning > cooktove that is currently being developed in Nepal. The analysis would > involve simulation to predict the performance of the cookstove and would set > up a benchmark for improved stove manufacturing in Nepal. This analysis would > also assist in providing the experimental and the simulation results towards > getting the stove certified as an “Improved Cookstove”. > > However to simulate the dung burning I had to resort to using the fixed heat > source instead as modeling combustion/pyrolysis of dung was beyond the scope > of the project. So what could be the heat output from burning 1 kg. of dung. > How mush heat would be released from this ? Is that the calorific value dung > ? As I would be using a fixed temperature heat source, what could be that > temperature ? > > Cheers > > Sarbagya Tuladhar > > On 13/02/2012, at 2:27 AM, Anand Karve wrote: > >> Dear Richard, >> The undigested solid matter in the dung is in fact the lignocellulosic >> matter, However, in the case of ruminents, it is not in a fibrous form but >> in the form of particles due to the practice of chewing the cud. It is the >> dung of non-ruminents, like horses and elephants that has fibres. >> Yours >> A.D.Karve >> >> On Sat, Feb 11, 2012 at 11:30 PM, Richard Stanley <[email protected]> >> wrote: >> Ad, >> >> I don't personally think the solids would be of much value for a good >> briquette: What I would look for personally, is your lignocellulosic >> material, ( the more fibrous stuff) to encapsulate other more carbon rich >> salt free, materials sawdust charcoal crumbs/ dust, selected agro residues >> with aromatic-or non aromatic- considerations depending upon what kind of >> fuel aroma and duration of heat you desire. >> >> Richard Stanley >> >> >> On Feb 10, 2012, at 9:36 PM, Anand Karve wrote: >> >> Cattle dung consists mainly of non-digestible lignocellulosic material, >> millions of micro-organisms, mucus produced by the animals and by the >> microbes, and some minerals. In fact it is the microbes and the mucus in the >> dung that yield biogas on anaerobic fermentation. A pressurised sieve, >> technically called a filter press, is the best device for separating the >> non-soluble solids from the fluids. If the fluids contained the microbes and >> the mucus, they should be subjected to anaerobic digestion before allowing >> them to be used as manure. Dung also has a very high ash content, because >> of which its calorific value is rather low. Dry dung has calorific value of >> about 3500 kcal/kg. Has anybody measured the calorific value of the solids >> in the dung, after removal of the fluids from it by using a filter press? >> Yours >> A.D.Karve >> >> On Sat, Feb 11, 2012 at 8:27 AM, Sarbagya Tuladhar <[email protected]> >> wrote: >> Hi Boston >> >> >> I volunteered with EWB Australia in Nepal working on a clean dung burning >> stove and thus worked with the dung as a fuel . Washing of the dung was done >> and briquettes which was a real success. Paper pulp used as a binder worked >> really well. Also the chloride contents of the dung which is responsible for >> watery eyes was removed on washing the dung which was proven by the copper >> wire test. We even fabricated a simple dung press for the same. The liquid >> portion of the dung was reutilised as manure in the fields. Thus the whole >> sceptism about "should" use dung as manure in the fields and not as a >> cooking fuel was somewhat solved. Did not test the NPK contents of the >> liquid portion though... >> >> Sarbagya >> >> Sent from my iPhone >> >> On 11/02/2012, at 2:06 AM, Boston Nyer <[email protected]> wrote: >> >>> Hello, >>> >>> I'm looking to clean/rinse cow dung and do not have any experience doing >>> so. Does anyone have any experience cleaning dung and would like to share? >>> >>> >>> Thank you! >>> Boston >>> >>> -- >>> Boston >>> Skype: BostonNyer >>> Cell: (585) 503-3459 >>> www.burndesignlab.org >>> >>> _______________________________________________ >>> 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/ >>> >> >> _______________________________________________ >> 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/ >> >> >> >> >> >> -- >> *** >> Dr. A.D. Karve >> Trustee & Founder President, Appropriate Rural Technology Institute (ARTI) >> >> >> _______________________________________________ >> 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/ >> >> >> >> _______________________________________________ >> 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/ >> >> >> >> >> >> -- >> *** >> Dr. A.D. Karve >> Trustee & Founder President, Appropriate Rural Technology Institute (ARTI) >> >> >> _______________________________________________ >> 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/ >> > > _______________________________________________ > 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/ > > > > _______________________________________________ > 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/ > > > > > > _______________________________________________ > 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/ > > > > > > -- > *** > Dr. A.D. Karve > Trustee & Founder President, Appropriate Rural Technology Institute (ARTI) > > > _______________________________________________ > 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/ >
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