Instructables

anybody know how to keep a lit gas from lighting the gas in a fuel tank? I'm building a hydrogen stove or burner.

I need to keep the lit hydrogen from lighting the compressed tank of hydrogen. The only things between the burner and the tank is a hose and a valve.

ahmad21174 years ago
i dont think you should use hydrogen since its too dangerous and if it gets burned the heat would be too high to grill meat on
RPoooBear4 years ago
yes you prvent the hydrogen from bakingup by using a small part of sigarett but just cut it in half and use plastic tubing for your fuel line
Dr.Bill5 years ago
another way to do this is to bubble the gas through a jar of water. back flash then only goes as far as the jar
Dr.Bill5 years ago
i have a friend that did this, he packed the end of the pipe with coarse steel wool not too tightly so as to stop the flow of gas
Kiteman5 years ago
As long as the gas flows out of the tank at the same speed as the flame burns along the gas, you're fine. As benthekahn said, if the gas is pure (i.e. contains no oxygen), then the flame will go out if it gets inside the tubing.
___ Kiteman5 years ago
However if it contains oxygen.......BANG!
MAKE SURE YOU HAVE A WET AND OR DRY ARESTOR
fozzy135 years ago
you need a flashback arrestor. There are tons of different ways to make one, I use an aquarium blue filter stone in some brass fittings from home depot. Probably the most popular one is the bronze wool design where you stuff a bunch of fine bronze wool into a length of pipe to stop the backward burning. If you search youtube for "flashback arrestor" you'll find countless designs. Hope this helps.
oxylight5 years ago
In order to prevent the flame from moving up the fuel line the maximum diameter of the fuel port needs to be less than .057 cm (.0225 in). The stainless steel wool that you place outside the port is actually not a flame arrestor but a catalyst.
Ultra Computers (author)  oxylight5 years ago
What do you mean by fuel port?
This is the small hole that the hydrogen fuel comes out of to mix with the air and burn. As long as this hole is less than .0225 inches in diameter the flame will stay out of the fuel delivery tube.
benthekahn5 years ago
Well if there is just hydrogen in the tank (no oxygen) then you shouldn't have any problems because hydrogen needs oxygen to ignite. Pure hydrogen will only burn once it leaves the burner and is exposed to the surrounding air. Warning, I am by no means an expert with any of this so try your stove at your own risk.
Ultra Computers (author)  benthekahn5 years ago
Thank you . I'll keep that in mind.
Slight problem with the above-the gas can burn back through the line, it happens to welding torches and is the reason for flashback arresters on welding hoses. I've heard that some sort of laminar flow of gasses gets set up where oxygen gets in along the outside edge of the hose and flame byproducts go out the center. I've seen stainless steel wool used as a flame stop for hydrogen, the trick being that the spaces have to be too small for the flames to propagate through to the other side. Each gas has a different size, and I believe that hydrogen's is particularly small.