[Stoves] Pellets in Uganda was Re: Cuber and size of densifying machines.

Paul Anderson psanders at ilstu.edu
Sat Mar 15 10:37:32 CDT 2014


Dean,

Please tell us about those pellets:  characteristics and source and used 
in what stove(s).    The experience by Awamu in Uganda does not agree 
with your statement.   But there could be different sources and 
different stoves.

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 3/6/2014 1:20 PM, Dean Still wrote:
> Hi Tom,
>
> In Uganda the pellets were too dense and were hard to light. Do you 
> know the density of USA heating stove pellets?
>
> Best,
>
> Dean
>
>
> On Thu, Mar 6, 2014 at 11:02 AM, Tom Miles <tmiles at trmiles.com 
> <mailto:tmiles at trmiles.com>> wrote:
>
>     Richard,
>
>     You probably mean 0.6 g/cm3 (37 lb/ft3) which is very good that's
>     better than most commercial wood pellets. For reference the dry
>     density of sawdust is often about .160 g/cm3 (or 10 lb/ft3). The
>     loose density of straw is about 0.08 g/cm3 or (5 lb/ft3). The
>     press roll on a pellet mill exerts about 142 bars (2000 psig). If
>     you can get those densities by selecting materials, wetting,
>     pressing at 12 bar and drying you are doing very well.
>
>
>     Tom
>
>     *From:*Stoves [mailto:stoves-bounces at lists.bioenergylists.org
>     <mailto:stoves-bounces at lists.bioenergylists.org>] *On Behalf Of
>     *Legacy Found
>     *Sent:* Thursday, March 06, 2014 10:46 AM
>     *To:* Discussion of biomass cooking stoves
>     *Subject:* Re: [Stoves] Cuber and size of densifying machines. (no
>     longer Re: The wood and char and fuel "debate" )
>
>     Crispin, what densities are you seeking. We have seen densities of
>     up to  0.6kg/cm^3 by use of really fine granular material charcoal
>     sawdust and certain other ag residues as infiller in hand presses
>     generating only about 12 bars pressure.
>
>     I have not attempted pellet production but have no doubt that high
>     pressure is not needed: Rather its more about attention  to blend
>     particle density and size and variations between these (sorting
>     coefficients) that makes the difference density wise.
>
>     May look into it if anybody is interested in the fuel pellet world.
>
>     Richard
>
>     Sent from my iPhone
>
>
>     On Mar 6, 2014, at 11:38, Crispin Pembert-Pigott
>     <crispinpigott at outlook.com <mailto:crispinpigott at outlook.com>> wrote:
>
>         Dear Friends
>
>         I agree with Dean on this score. The air flow through the
>         pellets strongly affects the way they burn if the device is
>         constructed such that the fuel contributes a significant
>         element of air control.
>
>         These devices
>
>         <image002.jpg>
>
>         Are 'cubers' in that they are producing densified lumps that
>         can be put into a stove. But they will work best in a large
>         stove such as is used in China for space heating and cooking.
>         The input material is straw and other stover.
>
>         The mechanism is an eccentric roller running inside a
>         perforated cage at maybe 60-100 RPM. As Tom notes, power
>         consumption is about 110 kW.
>
>         So far I don't think the product is economically viable as
>         there is a subsidy involved. What we need is a breakthrough
>         technology that will make densified fuel without the need for
>         heat.
>
>         Regards
>
>         Crispin
>
>         **
>
>         Hi Paul,
>
>         I have seen the very small pellets sold for heating stoves in
>         the US burn very cleanly. Larger sized pellets did not burn as
>         cleanly.
>
>         Best,
>
>         Dean
>
>         _______________________________________________
>         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/
>
>
>
>
>
> _______________________________________________
> 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://stoves.bioenergylists.org/
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20140315/0a84d2d6/attachment.html>


More information about the Stoves mailing list