Minerals Report - International Seabed Authority

pressure. He said that with the same geothermal gradient, the hydrate
layer disassociates from the bottom and provides gas into the system. Dr.
Desa described a third potential method called an inhibitor injection,
which takes advantage of shifting the phase boundary.
After the production and recovery of the hydrates, Dr. Desa said
that several ideas have been offered for their transportation to shore. These
included the use of pipelines to transport the recovered hydrates to shore
or converting the recovered methane hydrate to liquid hydrocarbon and
transporting this product to shore, or converting the recovered methane to
pure hydrate (methane free of sediment), storing it in zeppelin shaped
storage tanks for subsequent towing to a shallow water infrastructure
where the hydrates can be safely decomposed into water and gas in a
controlled environment. Dr. Desa said that many scientists do not think
that the pipeline idea is a good one because it would involve
transportation across the continental slope that is sometimes unstable
because of avalanches. On the conversion of methane to liquid
hydrocarbon, Dr. Desa said that in this method the methane would be
broken down to form carbon monoxide and hydrogen. Through the use of
a catalyst, Dr. Desa said that these two chemicals could be converted to
liquid hydrocarbon that is easy to transport. He noted that it is estimated
that 35% of the energy contained in the methane would be utilized in the
process.
On the matter of by products from the production of methane
hydrates, Dr. Desa mentioned desalination, the sequestration of carbon
dioxide, the separation of gasses and energy generation as possibilities.
He said that by products are important because of the possible ancillary
funding that they could provide, and also because of the perception of
progress in the project being undertaken
Dr. Desa said that concerns that have been expressed about
developing gas hydrates arise because these deposits represent a delicate
balance between many facets of the environment. Among these, he
mentioned pore water, sediments, fluids, the overlying water pressure and
temperature. He identified the global climate and the geological
environment as situations that could be adversely impacted by hydrate
production. With regard to the global climate, Dr. Desa said that methane
in hydrate form is about 3,000 times that found in the atmosphere, with a
green house potential output of about 10. He said that during the last
glaciation there was a fall of sea level. He also said that a reduction in the
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