[Stoves] Cleaning Dung

Paul S. Anderson psanders at ilstu.edu
Sun Mar 18 15:31:21 CDT 2012


Dear Sarbagya, Ron and all,

1. So you had contact with the Univ of Adelaide fellows!!!  Great guys  
who attended the BEF Stove Camp in Australia about a year ago.  Please  
share with us any and all of their reports, plus your work.

2.  Seems you are not at U of Adelaide any longer, correct?  What  
university are you with?

3.  Now that we know you are using a Servals Champion TLUD, there can  
be comparative data from Servals and also from a study done in Nepal a  
couple of years back.  I assume that you have that report?  And we ask  
Sujatha and Rajan at Servals to provide other data if available.

4.  I agree with Ron that the word "burn" should be avoided.  Better  
to use pyrolyzed, and char-gasification and some term for "complete  
combustion of the fuel" (meaning both the pyrolysis and the  
char-gasification that results in only ash remaining).

5. You wrote:
> We experimented by burning about 290 grams of dung briquettes. This  
> took a total of 7 minutes to boil 1.5 l of water as opposed to using  
> 325 grams of unwashed dung to boil the same amount of water in 21  
> minutes. The type of stove used to conduct this experiment was a  
> traditional 2 pot mud stove.

Something seems out of wack here, and suggests replication is needed.   
The moisture content of BOTH fuels should be noted.  And I doubt that  
the traditional 2-pot mud stove will give very consistent results.   
The unwashed dung is only 10% more weight but burned for three times  
as long.  And accomplishd the same task of boiling 1.5 liters of  
water.  Too many unclear issues to simply accept those numbers.

6.  Also, is what is washed from dung better, same, or worse for  
energy content than what is left in the washed dung?  This has  
probably been studied, but I do not know that answer.  Anybody?

Clearly your study has attracted the interest of some on this Stoves  
Listserv.  Please keep us posted, and tell us you timetable for main  
parts of your work.

Paul

Paul S. Anderson, PhD
Known to some as:    Dr TLUD      Doc      Professor
Phone (USA): 309-452-7072   SKYPE: paultlud   Email: psanders at ilstu.edu
www.gtz.de/de/dokumente/giz2011-en-micro-gasification.pdf (excellent ref.)
My website specific for TLUD information: www.drtlud.com  =  www.DrTLUD.com


Quoting SARBAGYA TULADHAR <sarbagya007 at gmail.com>:

> Hi Ron,
>
> I have not yet got to the stage of optimizing stove features as yet.  
> However, I am working on the secondary air inlets for the combustion  
> of the gases inside the combustion chamber which would aid in the  
> heat transfer to the cooking pot. Well, we did conduct experiments  
> on "combusting" the dung. We also did the dung briquettes. The dung  
> cakes in its raw form (without briquetting) yields a lumpy form of  
> ash which does not break down thus posing problems in the combustion  
> chamber as blocks the entry of primary air. However, the community  
> used this ash-form to washing their dishes and also as a manure in  
> the fields. With the dung briquettes, the ash form was no more lumpy  
> and thus was not blocking the entry of primary air. Dung briquetting  
> yielded an amazing find as the liquid content on "dung washing"  
> could be used as fertilizers in the fields thus improving soil  
> altogether.
>
> We experimented by burning about 290 grams of dung briquettes. This  
> took a total of 7 minutes to boil 1.5 l of water as opposed to using  
> 325 grams of unwashed dung to boil the same amount of water in 21  
> minutes. The type of stove used to conduct this experiment was a  
> traditional 2 pot mud stove.
>
> Cheers
>
> Sarbagya
>
> On 18/03/2012, at 12:21 PM, rongretlarson at comcast.net wrote:
>
>> Sarbagya and list:
>>
>>    I tried googling for your project and found something almost a  
>> year ago from Josh Wilkey on this list.  I think we can help you a  
>> lot more if your team has produced a report.  Since you are doing  
>> CFD, it would be helpful to know what you have been learning from  
>> that.  Have you optimized anything yet?
>>
>>    Since you are using the Servals unit and only getting 12 minutes  
>> at a time, it is obvious that you need to densify. - which  
>> presumably means pelletizing.  Since you are intending operations  
>> in Nepal, and maybe rural Nepal, maybe you have discarded that  
>> option.  But I would look
>>
>>   You scare me when you use a sentence like this (from below - and  
>> similar was used by Josh):
>>        "So what could be the heat output from burning 1 kg. of dung."
>> Are you truly  "burning" - which I take to mean no char output?
>>    Can you give us some more ideas on what you have already learned  
>> from your experiments?  Are you getting (or could you obtain) about  
>> 25% char yiel
>>   You asked below about energy content of the dung per kg.  I think  
>> it must be about 15-18 MJ - depending on the ash content.
>>
>>     I worry a great deal about "burning" dung.  The whole point of  
>> making char is to improve the soil and maybe especially in Nepal.   
>> But Char from dung can be of extra value - as proven in numerous  
>> soil experiments.   Is you team into the soil side of char at all?   
>>  I hope that the word "burn" is a misnomer.
>>
>>    You asked about the flame temperatures.  This will be strongly  
>> dependent on the excess air you are getting.  Can you supply any  
>> data on the weight of a fuel load that lasts 12 minutes?  What is  
>> the volume of the fuel space and the shape (and density) of that  
>> fuel.  I would think your own tests could supply temperature data -  
>> using thermocouples.
>>
>>    I would look closely at the Georgia Tech computations of the  
>> last few days on this list and see if they might not answer some of  
>> your questions.
>>
>>    For others - the Servals unit is a nice looking commercial  TLUD  
>> unit from Chennai India, developed with Paul Anderson. See
>>      http://servalsgroup.blogspot.com/
>> and
>>     http://www.slideshare.net/bitmaxim/servals-tlud-biomass-stove-deck
>> (and there are more)
>>
>>   I have seen some technical data in these, but assume there must  
>> be a good bit more.  Paul?
>>
>>
>> Ron
>>
>> From: "Sarbagya Tuladhar" <sarbagya007 at gmail.com>
>> To: "Paul S. Anderson" <psanders at ilstu.edu>
>> Cc: "Discussion of biomass cooking stoves" <stoves at lists.bioenergylists.org>
>> Sent: Saturday, March 17, 2012 5:37:57 PM
>> Subject: Re: [Stoves] Cleaning Dung
>>
>> Hi Paul,
>> Dung burning using TLUD as a project had been conducted by the  
>> final year students of uni of Adelaide of which I was lucky to be a  
>> part of. This project was conducted under the EWB Australia  
>> humanitarian undergraduate project. Excellent work was done on  
>> this. I would very much try to incorporate their findings in my  
>> report.
>>
>> Cheers
>>
>> Sarbagya
>>
>> Sent from my iPhone
>>
>> On 18/03/2012, at 7:00 AM, "Paul S. Anderson" <psanders at ilstu.edu> wrote:
>>
>> > Sarbagya,
>> >
>> > I want to encourage your research on modelling cookstoves in Nepal.
>> >
>> > Please be aware of the Improved Cookstoves called TLUDs and the  
>> newest (and major) variation called TChar (TLUD top and Charcoal  
>> stove base).   (TChar is described in 3 documents at     
>> www.drtlud.com   and is the focal point of some stove initiatives  
>> in Uganda and Haiti.)  Some studies of TLUD stove issues in Nepal  
>> have been conducted, with favorable results, but limited by lack of  
>> funding in the recent past.
>> >
>> > The TLUD stoves (including the TChar variation) can utilize dung  
>> briquette fuels very well.  In India I successfully experimented  
>> with "dung tablets" that are easy to make in sizes such as  
>> rectangles that are 2 - 3 cm on each side and about 1.5 to 2.5 cm  
>> thick.
>> >
>> > I hope that your modelling will include the TLUD approach to  
>> using dung as fuel.
>> >
>> > Members of this Stoves Listserv would appreciate knowing more  
>> about you, your university, and objectives and methods.
>> >
>> > Doc
>> > --
>> > Paul S. Anderson, PhD
>> > Known to some as:    Dr TLUD      Doc      Professor
>> > Phone (USA): 309-452-7072   SKYPE: paultlud   Email: psanders at ilstu.edu
>> > www.gtz.de/de/dokumente/giz2011-en-micro-gasification.pdf (excellent ref.)
>> > My website specific for TLUD information: www.drtlud.com  =   
>> www.DrTLUD.com
>> >
>> >
>> > Quoting SARBAGYA TULADHAR <sarbagya007 at gmail.com>:
>> >
>> >> 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  
>> <rstanley at legacyfound.org> 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  
>> <sarbagya007 at gmail.com> 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 <bostonnyer at gmail.com> 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
>> >
>> >
>> > ----------------------------------------------------------------
>> > This message was sent using Illinois State University RedbirdMail
>> >
>> >
>>
>> _______________________________________________
>> Stoves mailing list
>>
>> to Send a Message to the list, use the email address
>> 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://www.bioenergylists.org/
>>
>
>



----------------------------------------------------------------
This message was sent using Illinois State University RedbirdMail






More information about the Stoves mailing list