Paraffin single pot stove testing

Crispin Pemberton-Pigott, New Dawn Engineering SZ

August 16, 2004

Dear Stovers

Further to my earlier report about a simple to make paraffin stove for the Free State Technikon that burns pretty cleanly I have some follow info that may be of interest.

Tonight I was testing various layouts of red hot plate that is what the paraffin hits in order to ignite the CO properly and I think the ideal

combination is now at hand.

I am using a perforated piece of 1.2mm stainless steel sheet on top with three 'talons' under the preheater pipe to light the gas as it approaches

the hot perforated plate. There is basically no way around the plate for gases to pass to the pot. Everything must come through the plate. Paul you

might like to comment on the pictures I will send you separately. The plate is hot enough to maintain ignition.


THICK WALL TUBE SIMPLE JET	THIN PLATE WITH IGNITER STRIP	THICK PLATE WITH TAPERED TALONS

There should be about 40mm between the jet of paraffin gas, and then the little metal 'talons' (pre-igniters as I called them) then 8mm of height

which is the preheater tube diameter, then a clear gap of 6mm to the hot perforated plate.

I have startlingly low CO figures for this combination. I do not have a temperature for the plate but it is in excess of 900 deg C. I got several

readings of 0.0009 as the CO fraction of the CO2 with the concentration of CO2 in the emissions in the 10% range. That was taken directly from the

edge of the fire. The COswings back and forth through 0.0013. The swinging is probably due to the meter not the stove. It means approximately only 1 carbon atom in 1000 is failing to find 2 oxygen atoms.

I will send a 1.5 KW sample stove to Ludrick Barnard late this week and the company that agreed to make some tiny fuel control valves is going to have samples this week. The jets are off the shelf in certain places.

The first training will take place in Bloemfontein on 6 or 7 September for 2 days. Anyone interested in getting trained after that can contact Ludrick

Barnard (see address in header).

BLUE FLAMES ON TOP

Regards

Crispin


TEST SETUP WITH AIR SAMPLING TUBE	TEST SETUP

June 3, 2004

Dear Aspirant Paraffin Stove Makers

The Paraffin Safety Association of South Africa is holding a paraffin stove designing competition.

See their website for reports and performance tests, safety standards and much more.

I received a call from Nazeema Ahmad last week saying they are having a conference on the subject and they are full into the media with ads on

paraffin safety this week. Big money behind this initiative.

See http://www.pasasa.org/new/safeStove.html

Testing is according to the South African Bureau of Standards test:

"All nine stoves tested failed the current SABS standards;

All the stoves failed an average of six or more of the SABS codes; " etc

Comprehensive tests are given for all the popular pressure and wick stoves

from the links on this page.

"Paraffin Safety Association added an additional test to the SABS standards

"After operating the stove for 1 hour, knock it over, while it is in

operation and note the consequences". Again, the most commonly used paraffin

stoves, non-pressure or wick stoves, all immediately erupted in flames when

knocked over."

The Panda stove explodes in a huge ball of fire when subjected to this last

test as the fuel is about 20 degrees above the flash point. I say 'last

test' because the stove is unusable after it has been knocked over once.

Frequently hundreds of homes are burned down because they are so close

together.

CRISPIN