Posted by John on August 28, 2003 at 22:06:45:
In Reply to: question posted by budi kusuma jaya on 08:36:05 08/28/03:
Budi,
I am not expert in this subject, but the basic principal of a flame arrestor is to cool the gas to a low enough temperature that it can not cause a futher explosion or fire. In the case of a marine engine, an engine backfire through the carburator could ignite gasoline fumes that might be present in the closed engine compartment. In addition to requiring ventalation, the US Coast Guard requires that gasoline engines have flame arrestors mounted on the air intake. In the case of the old Atomic 4 engine, it is a simple device consisting of multiple metal plates arranged close to each other so that the air can pass between them into the carburator. In the case of a backfire, the burning gas will go in the reverse direction and be cooled by the metal plates before it reaches the outside air. The design of an effective flame arrestor must have a long enough path to allow enough cooling. You should make a web search on "flame arrestor". Most matches do not seem to have much useful information, but something should be there. I found a flame arrestor that is claimed to be especially suited to biogas at this website:
http://www.varec-biogas.com/vr_fa.htm