At 1:18 AM 10/23/4, Grimer wrote: >At 03:23 pm 22-10-04 -0800, you wrote: > >>............. Hydrogen pipelines, like gas pipelines, carry some major >>risks. Since their engineering and implementation would be fairly new, and >>hydrogen is more difficult to manage, I would assume hydrogen risks to be >>higher than those for natural gas, both in transmission and delivery. > >When I was a boy my older brother used to make model airships out of balsa >wood and tissue paper. He filled them with "coal gas" from the gas stove and >they flew around the kitchen OK so I presume coal gas must contain a lot of >hydrogen. A search on the web gives the following data on "coal gas". > > ================================================================== > A typical composition of town gas would be about 51% hydrogen, > 15% carbon monoxide, 21% methane, 10% carbon dioxide and nitrogen, > ================================================================== > >They seemed to be able to handle toxic coal gas without killing too many >people* >in those early days of the 20th century. I can't see why handling a gas >which is >100% hydrogen would be much of a problem in the 21st century. Even in the most >famous accident involving hydrogen (the Hindenburg disaster) two thirds of the >nearly one hundred people on board escaped. > >Cheers > >Grimer > * apart from those distraught housewives who > deliberately put their head in the gas oven.
Yes, and I've seen lots of support for limited exposure to explosion when filling tanks and in accidents, etc. However, I would still expect transmission lines to have some surprises due to hydrogen embrittlement. This would especially be a problem for the gas tubines which would be hydrogen fueled and for the compressor blades used to push hydrogen upstream in the pipeline. High pressure valves, bearings, seals and lubricants would have to be tested long term, etc. In addition, a lot of engineering related to operations would have to be done, like modelling linepack, supercompressibility effects, jet engine performance, storage reservoir performance, and other parameters used in gas transmission simulations and operating models currently. Transmisson lines are considerably different from distibution systems, and a lot more dangerous. Broken natural gas transmission lines can and have wiped out very large areas by explosion. Hydrogen transmission lines might be able to do the same thing. The problem is doing the engineering to find out what kind of maintenance and operating procedures must be used to prevent it. Regards, Horace Heffner
