Environmental Engineering Reference
In-Depth Information
sand miles of hydrogen pipelines are in use around the world, with sever-
al hundred miles in the U.S. These lines are short and located in industrial
areas for large users. The longest pipeline in the world is almost 250 miles
long and goes from Antwerp to Normandy. It operates at 100 atmosphere
of pressure which is approximately 1,500 psi.
Air Products plans on constructing a new hydrogen production plant
in Port Arthur, Texas to supply 110 million standard cubic feet per day of
hydrogen to Premcor Refining and others on Air Product's Gulf Coast hy-
drogen pipeline system.
Pipelines may be the least expensive way to deliver large quantities
of hydrogen. Pipelines are the main choice for moving refined petroleum
products across the country. They are less than 10% the cost of rail, road or
water tankers. The U.S. has almost 200,000 miles of interstate pipelines for
petroleum products. There is another 200,000 miles of interstate natural
gas pipelines.
Hydrogen pipelines are expensive because they must have very ef-
fective seals. Hydrogen is also reactive and can cause metals, including
steel, to become brittle over time. Hydrogen pipelines of 9 to 14 inch di-
ameter can cost $1 million per mile or more. Smaller pipelines for local
distribution cost about 50% of this. Siting major new oil and gas pipelines
is often political and environmentally litigious. Political pressures may fa-
vor one location over another. Whether global warming concerns will be
enough to override other considerations is still unknown. Pipelines are
more likely to be used for hydrogen transport once there is real demand.
Trailers carrying compressed hydrogen canisters provide a flexible
way of delivery suited for the early years of hydrogen use. This is a rela-
tively expensive delivery method since hydrogen has a low energy density
and even with high-pressure storage, not that much hydrogen is actually
being delivered. Current tube or canister trailers hold about 300-kg of hy-
drogen which is enough to fill sixty fuel cell cars. It is estimated that with
improved high-pressure canisters, a trailer could hold about 400-kg of hy-
drogen or enough for about 80 fuel cell cars. A tanker truck for gasoline
delivers about 26 metric tons of fuel, or 10,000 gallons which is enough to
fill 800 cars.
About one in 100 trucks on the road is a gasoline or diesel tanker.
Replacing liquid fuels with hydrogen transported by tube truck means
that about 10% of the trucks in the U.S. would be transporting hydrogen.
Technology may provide better options in the future since there is signifi-
cant R&D going into each of the storage and transportation technologies.
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