(Visiting MSc student from Kyushu University)
"A Simple Analysis Model on Gas Production from Methane Hydrate Layer by Depressurization Method"
The existence of Methane hydrate (MH) is confirmed in the deep-sea sediment and the permafrost,
it is expected to be an unconventional hydrocarbon energy resource. MH was discovered in the seabed
around Japan, the development of MH has been conducted to product as a domestic energy in the future. Hereafter,
in order to switch to commercial production, the economic evaluation will be indispensable. Therefore it is effective
in an analysis model to predict the gas production from MH and conduct parameter survey simply. This paper presents the analysis
model, which is composed of some equations related to MH production/dissociation. As gas production method, we treat depressurization
method that MH reservoir pressure is lead to below MH formation/dissociation equilibrium pressure by lowing bottom hole pressure (BHP).
This paper revealed the result of gas production from MH through analysis model, inspected its validity by comparing to the result of
numerical simulation using STARS on the same reservoir condition. Furthermore, in order to understand the factors of determining gas
production rate for depressurization method, we conducted the sensitive analysis by changing various parameters related to MH layer.