[Stoves] Correcting a misconception that approaches myth status

Wed Dec 17 09:17:11 CST 2014

Ron and all,

I echo and re-double your thanks to all who have saved those earliest 
messages of the Stoves Listserv.   AND send thanks to those (Ron 
included) who wrote those messages in 1996.   (even though a strange 
Date of Aug 31, 2004 keeps showing in the headers?)

About the computer modeling of TLUDs, there was a large grant given to a 
group at Colorado State Univ, and they are expected (according to Dean) 
to be part of the presentations at ETHOS 2015 (6 weeks from now!!).

Paul

Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
Email:  psanders at ilstu.edu
Skype: paultlud      Phone: +1-309-452-7072
Website:  www.drtlud.com

On 12/16/2014 11:30 PM, Ronal W. Larson wrote:
> Dean, cc Paul, Crispin, List
>
> 1.  I can support your proposal on summarizing TLUD experimental 
> history.  But just as valuable would be a computer modelling RFP 
> (presumably from GACC, so I add Ranyee as a new cc).  There are 
> hundreds of biomass combustion/gasification/pyrolysis folk out there 
> who could bring highly sophisticated computer programs to bear right 
> away.  Finally the stove community has the money to do this.   A TLUD 
> has to be much easier to computer-simulate than any other stove.
>
> 2.  Some of the recent conversations have mentioned BLDD stoves - of 
> which I know not one recent example on the cooking side (which this 
> list is mostly about).  To check that, I did a search on several 
> approaches that grew out of the excellent Dutch work on BLDD stoves - 
> and in particular by a Dutch transplant to Australia - Dr. Pet 
> Verhaart.  I was amazed to find that Tom Miles or daughter Erin 
> Rasmussen must have found the early records of this list beginning in 
> 1996, which I thought had been lost (see 
> http://www.bioenergylists.org/newsgroup-archive/stoves/1996-February.htm for 
> the first month history).   If anyone knows some earlier 
> communications on TLUDs on a different (but still Tom Miles) list, I 
> hope they can report where they are.
>
> 3.   I suggest to Dean that this above source should be part of the 
> “progress history.  In that first month, we had contributions from 
> Mark Bryden and Kirk Smith  (but not on TLUDs), which I had not 
> recalled.  Heavy participation in that first month from Piet’s 
> colleagues (Prasad, Moerman, etc) as well from Eindhoeven - especially 
> on BLDD cook stoves.
>
> 4.  I have mentioned the name Tom Duke several times on this list - an 
> Iowa farmer - who did several experiments (and one of the few lauding 
> char-making stoves in that first month) that I have not seen repeated 
> since - claiming good results even with zero-cost TLUDs.   I’m sorry 
> we have lost contact with Tom.
>
> 5.   I hope to read March 1996 in the near future;  by the end of 
> February, we had not yet found agreement that TLUDs would work.
>
> Thanks to Tom or Erin for finding this historical resource.  And to 
> those discussing BLDD stoves - which caused me to find what I thought 
> had been lost.
>
> Ron
>
>
> On Dec 16, 2014, at 2:00 PM, Dean Still <deankstill at gmail.com 
> <mailto:deankstill at gmail.com>> wrote:
>
>> Dear Paul and Crispin,
>>
>> My hope is that someone will do the experiments to detail how the 
>> work with TLUDs, etc has resulted in progress and publish the results 
>> in a peer reviewed journal. It might take a while but it's a job 
>> worth doing. Maybe find an interested student or professor to instruct?
>>
>> Best,
>>
>> Dean
>>
>> On Tue, Dec 16, 2014 at 7:42 AM, Paul Anderson <psanders at ilstu.edu 
>> <mailto:psanders at ilstu.edu>> wrote:
>>
>>     Stovers,
>>
>>     This is about Crispin's story and showing slow progress, but it
>>     is progress.
>>
>>     On 12/16/2014 12:51 AM, Crispin Pemberton-Pigott wrote:
>>>
>>>     There are dozens of ways to make a stove work improperly. Paul
>>>     and I have tried all of them, I think. Paul told me that a TLUD
>>>     fuelled with wood could not be refuelled. We were on the back
>>>     patio of my home in Ezulwini Valley in Swaziland and he went off
>>>     to do something, leaving a small TLUD can-stove running,. I fed
>>>     in some wood vertically and it worked just fine. I continued to
>>>     do so and it continued to run long after it should have gone
>>>     out. Thus I proved to myself (and Paul) that TLUD’s can be
>>>     refuelled but not too much at a time. OK, that was valuable and
>>>     contradicted received wisdom.
>>>
>>     His story is correct.   I remember it well (now that I have been
>>     reminded).   But it also tells us something about the progression
>>     of our science.
>>
>>     Back then, the importance of the MPF (Migratory Pyrolytic Front)
>>     had not been realized.   What Crispin did then in 2002 was what
>>     BP-Oorja, Biolite and Philips and others did years later.   They
>>     were all trickle feeding additional fuel into the TLUD well above
>>     the pyrolytic zone.   Heat from below was (and still is, if you
>>     do it) sufficient to pyrolyze the new fuel by heat WITHOUT the
>>     small flames of the pyrolytic front at that fuel.   The char can
>>     be fine, but probably a little different (not made at the higher
>>     temperatures of the MPF).
>>
>>     And when the MPF reached the bottom, and with new fuel placed on
>>     top of the char (not into the hot zone), the unit switched over
>>     to operating with Bottom Burning (BB) as a rather normal UpDraft
>>     gasifier.   And that leads to higher temperatures in the bottom
>>     (air coming onto charcoal) and the need for the different
>>     materials (cast iron, ceramics, special metals) to protect that
>>     hot zone.
>>
>>     As I have written in "Micro-gasification Terminology: An
>>     Instructional Summary of MG", available at my website.   See:
>>     http://www.drtlud.com/wp-content/uploads/2013/11/micro-gasification-terminology-14nov2013.pdf
>>
>>>     Therefore, there are actually two types of TLUD (device name)
>>>     gasifiers, one being TLUD-MPF and the other being TLUD-BB. The
>>>     two types are quite distinctive in operation, and deserve
>>>     separate recognition and study. The common usage of the “TLUD”
>>>     name today means more than the TL of “Top-Lit” can signify.
>>>     ...... snip ...  In essence, TLUD is a name for the small
>>>     updraft gasifier processes/stoves and is not a description of
>>>     what process (MPF or BB) is actually happening. However, we
>>>     expect that in common usage, the TLUD name will designate
>>>     TLUD-MPF, unless the UD-BB mode is specified.
>>     However, many people continue to ignore the transition from MPF
>>     to BB.   Back in 2002 I had no clue about this.   Now I consider
>>     it essential knowledge for understanding the variations within
>>     micro-gasification technology.   (Note that I wrote
>>     "micro-gasification technology" and not "TLUD technology.")
>>
>>     I repeat:
>>>     However, we expect that in common usage, the TLUD name will
>>>     designate TLUD-MPF, unless the UD-BB mode is specified.
>>     Of course I can only suggest and request.   People will do what
>>     they want to do, sometimes unfortunately.
>>
>>     Paul
>>
>>     Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
>>     Email:psanders at ilstu.edu  <mailto:psanders at ilstu.edu>    
>>     Skype: paultlud      Phone:+1-309-452-7072  <tel:%2B1-309-452-7072>
>>     Website:www.drtlud.com  <http://www.drtlud.com/>
>>
>>
>>     _______________________________________________
>>     Stoves mailing list
>>
>>     to Send a Message to the list, use the email address
>>     stoves at lists.bioenergylists.org
>>     <mailto: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 <mailto: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 --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20141217/9d35aa65/attachment.html>