Hi Otto , The German machinery is very likely using the rolling or ball mill off concentric perforated cylinder design none of which will work with the wet process technology(pressures far higher than needed by just under one an order of magnitude in fact---and temperatures far too high for water based fiber migration into the necessary random alignment which allows binding of the mass ( there machines turn the water into steam with some not so funny results and they destroy any fiber strength in the process). Still some sawdust burs well other smokes and smolders. Simple test is to combust each element separately . We're finding differences in sawdust here too: major differences! Will see this all studied here, soon enough, and will revert back to list.
As to stoves in use, there is the Helps ONIL stove , the stove team products as reported by Gustavo Pena, the traditional plancha mud brick wrapped around a usually thin clay or metal dish ~ 14 to ~24" diameter, three stones and probably many more I have yet to learn about. Stove adaptation for bed or vice versa, does not seem to pose much of a problem to those 175 odd producers who are making using and selling the product here--not thus far at least. That minus 35C was a typo correct? Richard, a bit warmer, in MonteRico,Guatemala Sent from my iPhone On Jan 20, 2013, at 5:41, Otto Formo <[email protected]> wrote: > Dear Richard, > > Thanks for your concern. > The briquettes, I mentioned, was made out of a mixture of richusks and > sawdust from hardwood. > > We found them at a sawmill in Western Province of Zambia and was produced by > the owner of the mill, using a mobile briquetting unit made in Germany. > The quality of the pelletsmachine can not be questioned, but most likely the > mixture of husks and sawdust. (70-30%)? > We just tested a finished product and found them too loose and came to sort a > of "conclusion", that the mixture should be different, 30% husks and 70% > sawdust to perform better. > > We are just about to test solid briquettes produced in Sweden, made out of > sawdust from pine (softwood), right now. > > We very much like to be able to use briquettes, as well as pellets in the > gasification units, too, due to the lower costs of production and less > technical challanges. > > What type of stoves are you using in Guatemala? > > Otto > Back in Norway to -35 C > > From: [email protected] > Date: Sat, 19 Jan 2013 20:46:53 -0600 > To: [email protected] > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Dear Ottos, > Seems you both need training in briquettemaking . Jon you know where to go in > nchi yeti but Otto, where are you based? Seriously, the blends you are > finding smelly smokey etc suggests that you get in touch with any of hundreds > of others who can train you. > Richard Stanley > Monte Rico, > Guatemala > > Sent from my iPhone > > On Jan 19, 2013, at 18:10, Otto Formo <[email protected]> wrote: > > Josh and Jonathan (Otto), > > Yes, we are talking about the presscake of Jatropha and it was processed into > pellets localy in Zambia, quite easily and with "simple" tools - (no waste of > energy) > > We had the same experience as your colleagues using briquettes made out of > ricehusks and sawdust. > They even started to glow like charcoal early in the gasification process and > produced smoky and smouldery combustion. > > Thast why we prefer to use pellets of best possible quality. > > I hope you are correct about the gasification of jatropha pellets will > destroy the phorbol esters and other problematic compounds instead of > emitting them. > Iam a bit worried about the forced draft units, while they seems to blow some > parts of the ash and gases into the open air or room. > > May be the char from Jatropha could have a pestecide effect as well? > > Otto > Date: Sat, 19 Jan 2013 18:23:35 -0500 > From: [email protected] > To: [email protected] > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Otto - FYI jatropha presscake (the mealy material left over once oil has been > pressed out of the seeds) can be directly pelletized without further > processing. It's pretty easy to pelletize, even with a small, cheaper (e.g. > benchtop) pellet press. The mealy presscake still contains some of the oil > (think coffee grounds) and it pelletizes well without worry over moisture > content or having to use a binder. > > The pellets burn in a TLUD similar to wood or other pellets, at least by > visual observation and temperature recording. I have colleagues that have > tried to make cooking briquettes with jatropha seedcake and had a very smoky, > smouldery combustion. I believe there are concerns of some potentially toxic > emissions (phorbol esters, other compounds?). I have not tested the emissions > from TLUD charring jatropha pellets, but there was no visible smoke and the > gasifier seemed to operate fine as it does with other types of pellets. It > would be interesting to know if firing jatropha pellets in a TLUD destroys > the phorbol esters and other problematic compounds instead of emitting them. > > I first tried to char un-pelletized jatropha seedcake in the TLUD - because > it is mealy like coffee grounds no draft could get through and it was a total > fail - lots of smoke poured out! This brought the fire department to our > Colorado backyard during a fire ban. Whoops. > > Also FYI char made from TLUD jatropha pellets performed similar for herbicide > uptake from simulated natural water as chars made in the same way from pine > pellets, bagasse pellets, and bamboo pieces. > > Josh > > > > On Sat, Jan 19, 2013 at 12:29 PM, Jonathan Otto <[email protected]> > wrote: > Otto, > > > > Whole Jatropha seeds can be picked from hedges on-farm and used directly in > our jiko safi gasification stove without any further effort (except maybe for > some sun drying if harvested during a damp season) … the most decentralized, > efficient sustainable fuel system I can imagine. > > > > Sure, urban jiko safi users will need to buy their fuel seeds, so a > commercial system for transport and retail sale of seed will be needed > eventually, likely mimicking some aspects of the charcoal trade. But it’s > just whole, unprocessed seed. > > > > Concerning pelletized Jatropha fuel, I would like to understand the > advantages you find in going through the costs and effort (including energy > losses) of processing seeds to expel the oil, then probably milling the press > cake and shells (?) to uniform size/texture, then extruding or otherwise > forming the mixture into pellets, and finally distribute the fuel, some of > which will go back to the same farmers that grew the Jatropha seed in the > first place? > > > > I know there are technical advantages to gasification of uniform-sized > pellets, but it seems to me that round or ovoid shaped seeds like Jatropha, > castor (I know, more poisons!), shea or croton megalocarpus provide this same > advantage, without going through the pelletization process. What am I > missing? > > > > Otto, the minor > > > > P.S. It's too late for me to retire 'on time' > > From: [email protected] > To: [email protected] > Date: Sat, 19 Jan 2013 17:23:37 +0100 > > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Jonathan, > > We have got some samples of pelletized jatropha shells and seeds from Zambia, > after the oil has been extracted and we feel that is the way forward. > > We will update you on the progress, so you will be albe to retire "on > time".................:) > We are not so worried about PM in natural draft gasifiers, but thanks for the > concern. > > Otto........................ > From: [email protected] > To: [email protected] > Date: Sat, 19 Jan 2013 09:03:35 -0500 > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Otto- > > You 'would guess' wrong. > > 'We should be very careful advising people' about such unsupported > conclusions. > > The challenges of gasifying oils found in seeds, notably the oils of Jatropha > seed, in a cookstove are far different from working with most pellets > formulations. > > I keenly look forward to news of your all-fuel stoves that will handle J > seeds, and the results of your tests. I sincerely hope you develop this soon, > so I can finally retire in peace. > > Oh, and when you do tests, please include particulates in your emissions > testing, so we can finally end all this hand wringing about 'these types of > fuel'. > > >From the cheeky other Otto, > > Jonathan > From: [email protected] > To: [email protected] > Date: Fri, 18 Jan 2013 23:23:48 +0100 > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Dear stovers, > > I would guess that "any" gasifier will burn jatropha seeds or pellets cleanly > and efficient, as long as the moisture content are less than 10%. > > We have in the pipeline to test a new design of natural draft gasifiers, > using jatropha seeds and pellets, for emmissions and toxcic fumes. > > We should be very carefull adviceing people using these types of fuel, before > it has been carefully tested by independent institutions. > > Have a nice weekend. > > Otto (not the famous one..........:) > > From: [email protected] > To: [email protected] > Date: Fri, 18 Jan 2013 10:19:11 -0500 > Subject: Re: [Stoves] Jatropha fruit as fuel? > > Dear Jonathan > > I am interested in the general layout and dimensions of a stove that will > burn the seeds well. Are you sharing at this time anything regarding the > design? > > Thanks > Crispin > ++++++++ > > Dear Joyce and stovers all, > > My regrets for not responding to this request 6 months ago. I admit that it > got lost in my messy inbox which I have now reduced from 6000 messages to a > mere 2400, and in the process uncovered Joyce's email. > > Burning Jatropha seeds whole or in briquettes in open cooking arrangements is > a bad idea. It produces a smoky, smelly fire and probably exposes cooks to > toxic emissions. I even question burning Jatropha oil in lamps in enclosed > areas for the same reason. Maybe others know of emissions studies. > [snip] > > _______________________________________________ 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/ > > _______________________________________________ > 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/ > > > > > > -- > Josh Kearns > PhD Candidate, Environmental Engineering > University of Colorado-Boulder > Visiting Researcher, North Carolina State University > > Director of Science > Aqueous Solutions > www.aqsolutions.org > > Mobile: 720 989 3959 begin_of_the_skype_highlighting 720 989 3959 > end_of_the_skype_highlighting begin_of_the_skype_highlighting > 720 989 3959 end_of_the_skype_highlighting > Skype: joshkearns > > > > > _______________________________________________ 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/ >
_______________________________________________ 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/
