gas hydrate - CCOP

In "Development of the dissociation and the recovery method", the development of a new
dissociation method has been investigated in order to establish an efficient, economical
production method.
The flow of research regarding the above four research items is shown in Figure 3.
Figure 3. Research Scheme of the Production Method and Modeling Area
RECENT RESEARCH TOPICS ADDRESSED BY THE PRODUCTION METHOD &
MODELING GROUP
Development of determination of gas concentration in hydrate Using X-ray diffraction, gas
chromatography and Raman scattering spectroscopy in conjunction, a method that can
evaluate hydrate concentration and gas density was developed. In the Raman spectrum of
ethane and propane, the method of observing the C-C stretching vibration peak in addition to
a current C-H stretching vibration peak was found to be effective. In the case of the methaneethane
hydrate system, the gas density decreased with increase in ethane content and it
showed a minimum value at around 20 vol% of ethane content, and, as the ethane content rose
further, the gas density increased again. The X-ray diffraction patterns showed that the
structure-II was presented as ethane was introduced and all structure converted to structure-II
at the minimum point of gas density. This applied to a natural core sample that was taken
from the land region, and the crystal structure was clarified.
ANALYSIS OF A FRAME STRUCTURE OF MH SEDIMENT
Imaging technology to observe the structure of the MH sediment at the pore level was
established in order to quantify the relationship between the basic physical properties of the
MH sediment and the structure of the sediment. Micro-focus X-ray CT was selected to
measure the porosity and the saturation of the MH sediment sample non-destructively.
Moreover, to non-destructively observe the sand particles of the MH sediment sample and the
state of the distribution of the hydrate at high- accuracy, a scanning confocal optical
microscope was utilized. The sand particles and pores were identified from the CT image of
the artificial MH sediment and measured by the micro focus X- ray CT by the difference of
the CT value. The method that can calculate the porosity directly from each volume ratio was
established. The micro focus X- ray CT of the artificial MH sediment sample made by the gas
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New Energy Resources in the CCOP Region - Gas Hydrates and Coalbed Methane