[Stoves] Understanding TLUDs, MPF and more. (was Re: Bangladesh TLUD )

[Paul Anderson]

Dear Scott and Todd,       (another of 3 replies to about a dozen 
messages on this topic.  Not in any special order.  I thank everyone for 
their comments.)

The essence of TLUD operations is the pyrolysis stage.  Stoves that are 
true TLUDs and THEN continue to consume the char (which is called "char 
gasification") will end up with only ash.  They were operated in two 
ombustion modes (first was TLUD pyrolysis, and second was charcoal 
burning).  Those could be valid as stoves, but the second mode should be 
noted, and not simply called TLUD only stoves.

The other type of stove is the "fan jet" or high vortex  stoves like the 
Philips /ACE, which are designed to push plenty of secondary air 
downward onto the top of the created char, with the result of very 
little char production.   I prefer to not call them TLUD stoves, and 
instead use a name that is appropriate to recognize the distinctive way 
those stoves work, which may be more desireable to some people. Why call 
it a TLUD and not take credit for the powerful fan features?

Todd might specifically identify which stoves he is mentioning. [That 
would be a very appropriate discussion of the stoves that he is able to 
provide to interested people.   And DO include the prices.]

Ron's comments about the 3 main ways of handling the char (his message 
dated 10 Dec) is well stated. (He asked for my opinion.)

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 12/10/2017 2:25 PM, Scott Zager wrote:
>
> Thank you for helping a novice along.  Todd has help clarify that 
> there are many types of TLUDs.  Are they all intended to be gasifiers 
> with a secondary combustion chamber or collection tank for wood-gas? 
> Is it still pyrolysis if the stove combusts char to ash?  Perhaps I 
> should continue reading the literature.  Thanks again for your patient 
> assistance.
>
> Scott Zager
>
> *From:* Stoves [mailto:stoves-bounces at lists.bioenergylists.org] *On 
> Behalf Of *Todd Albi
> *Sent:* Sunday, December 10, 2017 1:05 PM
> *To:* Discussion of biomass cooking stoves 
> <stoves at lists.bioenergylists.org>
> *Subject:* Re: [Stoves] Understanding TLUDs, MPF and more. (was Re: 
> Bangladesh TLUD )
>
> Scott:
>
> Different TLUD stoves are designed to accomplish different tasks.  
> There are TLUDs  designed for different tasks.  Char production will 
> differs considerably from one design to another.  Many high efficiency 
> TLUDs designed for wok cooking produce minimal, if any char.  There 
> are lots of fan assisted TLUDs and natural draft TLUDs, designed for 
> cooking that produce minimal char, only minimal fine ash. Therefore 
> your glossary is incorrect leading off with the statement /TLUDs 
> automatically make char/ would be incorrect for many TLUDs that are 
> designed for cooking.  Although there a number of natural draft 
> cooking TLUDs designs too, that the definition maybe be somewhat 
> accurate for.  Our organization has several TLUDs designed for cooking 
> that produce only a thimble full of fine ash after cooking. Those 
> cooking implements obviously would no value for a stover, who sits on 
> the bio char production interest side of the fence.
>
> Many of the stove designs on this list have variable design 
> advantages, disadvantages, /depending on desired performance outcomes/ 
> of stove design.   I'd contend more complicated combination cooking 
> and thermal siphon heating stove designs, typically compact stove 
> designs with fans, large combustion chambers, and water tanks, would 
> not be viable transferring heat into larger volumes of water (high 
> mass), if designed to produced char at the same time. Large volumes of 
> char would impede ventilation and heat transfer, that is required to 
> maximize heat transfer into the water.  Heating the water would be the 
> greater energy task,  to reach the desired goal of thermal siphoning 
> in this simplified example.  In this type of stove, char production 
> would reduce stove thermal efficiency required to maximize heat 
> transfer to the water tank.
>
> Regards,
>
> Todd Albi, SilverFire
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20171211/7e88854a/attachment.html>