[Stoves] thoughts around ELFD Sampada / Venturi-burners / sooth

Wed Mar 30 00:01:31 CDT 2016

Martin you are inspiring me today.

A.D. How about adding something to the water? If you put in a little ethanol, which I know is very difficult to obtain in India, would it affect the quality of the combustion?

I know that an ethanol evaporator is possible and it may be that 2 or 5% or 10% ethanol will have some unexpected and beneficial effect on the flame. If all the vapour ends up in the flame there is nothing to lose in terms of fuel waste.

Co-firing often produces a much cleaner result than at least one of the fuels alone.

Regards from the DUE Conference
Crispin

Dear Anand and stovers,

it is great and I am happy, that the  ELFD-Sampada stove, invented by your daughter, Dr. Priyadarshini Karve, works excellent.

 I want to invite the stovers, to see and get aware, a general system in this stove.

All burners with forced draft are somehow "venturi-burners".
 Air-jets shooting into a gas-atmosphere suck gas into that air-jet.
In the TLUDs it is inverted to normal venturi gas-burners, and that is an excellent idea, because woodgas is not really pure gas.
It tends to clog nozzles by tars.

Now look to the ELFD-Sampada stove as a "double"-venturi burner-system.
1. vapor-jet drives air, in order to make
2. air-jets, which blow into woodgas, and each jet forms by that  a "somehow"-venturi-burner, as in a forced-draft TLUD.

Let me return to the simple gas-venturi-burners to guess about needed pressures:

LPG burners have a gas-pressure about 30 to 50 mbar; natural gas burners even lower ( 20 to 25 mbar?)
Rough assumed ( I am aware: big ratio-differences are possible): The streaming gas through the nozzle sucks about the same volume of air, to form together an excellent combustible mixture.
If so, that mixture could be made invers too: 30 to 50 mbar air-jet can suck the needed volume of woodgas.
And to get an  air-pressure about 30 to 50 millibar:
- A venturi-system driven by steam, -thumb-calculated-; has steam, pressurized to 100 mbar (or easily some lower or higher)

- Let us assume, that the steam condenses to water,
 naturally except the amount of water that is still in gas-form under that conditions (below 100°C).
 If the temperature in the system is above 100°C, there will be a lot of water(in gas-form) beside the air.
( same thumb "beginning" assume 50/50 above 100°C ??)
- The ELFD-Sampada shows in reality that the containing water does not disturb the combustion. In contrary it seems to help combustion in combination with forced draft. - I did not hear of speaking there would be water dripping out of the stove.

What about sooth and water?

The former discussion in the stoves-list about sooth, made me looking for sooth. I learned it is technically produced in different manners and in different qualities, for lots of purposes. - Yes they really want tons of sooth, we don't even want grams and want to avoid milligrams-
One solution to form sooth is to spray water into a flame.
Shouldn't we get to know, from industry by what amount  of water (and temperature) sooth starts to form, that we can avoid that?
And in contrary: what amount of water(in gas-form) makes burn better??

The lesson I learned:
As sooth is in parts like graphite, there are C's bound to C's, within a layer forming 6-rings, and that ring is so strong, that it needs more than 1000°C to burn/destroy the C-C-bondages.
-That means, we have to avoid _from beginning!_ the forming of sooth so strictly as possible, because it is so difficult to get it burnt.
- The simple truth I want to keep in my awareness:
Sooth is no charcoal-C and needs roughly double the temperature of charcoal to burn!

Just some of my ideas from before and after learning about the ELFD-Sampada-stove-

Kind Regards to all,
- and my compliments to Dr. Priyadarshini Karve.

Martin

_______________________________________________
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/20160330/bed29881/attachment.html>