Sir Humphrey Davy the 'Scotch Davy' lamp
"Rasczak
Am I the only one.... #
Posted Monday 11th January 2010 16:42 GMT
... who, after seeing the image accompanying the miniPAK, is a little concerned about using hydrogen as a power source in mining ?
"
ohh dear, history and science classes in Uk schools are so bad these days it seems...
namely the "'Scotch Davy'" gas miners safetly lamp.
basicly a gas light lamp encased in a fine metal mesh, if it comes in to contact with gas
in a an enclosed space such as a mine the gas can get in through the mesh and so
ignite that small amount inside the mesh as it comes into contact with the flame,
HOWEVER, the resulting explosion CAN NOT get passed the mesh to the outside.
http://www.welshminerslamps.com/info_lamp_history.shtml
"... thoroughly efficient safety lamp is not a mere mechanical contrivance for giving light in
a coal mine. It is an instrument constructed in accordance with established laws of physical science. It ensures the burning of a protected flame in the presence of explosive
gas, by regulating the necessary supply of atmospheric air, and by allowing the products
of combustion to pass through without igniting the gaseous atmosphere.
If the atmosphere is so heavily charged that noxious gas enters the lamp, its presence
will be indicated by a change in the length and color of the flame, and (unless there are
exceptional circumstances), the miner has sufficient warning to secure his safety.
The principles on which a thoroughly efficient safety lamp is constructed are practical, not theoretical...."
Fuel Cell (FC):
"A fuel cell transforms energy electrochemically. In a controlled fashion, without the use
of an open flame, a fuel cell converts the chemical energy stored in fuels like hydrogen,
methanol or methane, directly into electric energy. This is the reverse of the electrolysis
process. In addition to electrical energy, fuel cells produce water and heat as well. "
"Hydrogen:
Color- and odorless gas. Hydrogen is the smallest and lightest element on the periodic
table. A hydrogen atom consists of a negatively charged electron and a positively
charged proton. Hydrogen is the most abundant element in the universe. However, due to
its high reactivity it is mostly found in compounds, including water (H2O), hydrocarbons
(e.g. natural gas, which is mostly methane (CH4)), or crude oil."
http://www.h-tec.com/html/web/education/english/sub_produkte/brennstoff_brennstoffzellen.asp?id=2131
So in effect If you were wise as to put in place an extra safetly feature, them you add in a 'Scotch Davy' lamp style mesh into your final Hydrogen supply cylinder PEM device insuch cases, simple.