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Journal of Materials Science and Nanotechnology | Volume: 3
March 20-21, 2019 | London, UK
Materials Science and Materials Chemistry
2
nd
International Conference on
Mechanical behaviors of gas hydrate system: Ongoing development of phase-transition mechanics
Fulong Ning
China University of Geosciences, China
N
atural gas hydrates are ice-like crystalline substances
in which gas molecules are physically trapped inside
the polyhedral cavities of water molecules1–3. They occur
abundantly in both petrochemical production lines4 and
hostile environments such as seafloor sediments, arctic or
permafrost regions and even the surfaces of other planets.
Natural gas hydrates distribute widely in the offshore marine
sediments and onshore permafrost area under specific low
temperature and high-pressure conditions. Over the last few
decades, much attention has been directed toward them
as energy resources and for their environmental impact.
Understanding the mechanical behaviors of gas hydrate-
bearing sediments (GHBS) is important for their associated
applications in wellbore stability, stratumdeformation during
exploitation, geological disaster prevention, and the risk
assessment of replacing CH
4
with CO
2
in hydrate reservoirs
and CO
2
sequestration in oceans. In our work, we reveal the
mechanical mechanism of gas hydrate system at microscale
level using molecular dynamic simulations, AFM and CT scan,
investigate the static and dynamic mechanical responses at
the lab scaleusing direct shear tests and sonicmeasurements.
Then we used our mechanical correlation into the wellbore
and reservoir stability evaluation at the filed scale. Here we
firstly propose the conception of phase transition mechanics
which mainly investigate phase transition behaviors caused
by force, and mechanical response and flow behavior during
phase transition procedure by taking gas hydrate for instance.
e:
nflzx@cug.edu.cn