Development of Large Scale Production System for Methane Hydrates

摘要

Methane gas hydrate reservoirs have been recognized in a permafrostrnarea and under a deep sea floor, in which the temperatures andrnpressures were in the equilibrium condition of methane gas hydrate.rnMethane gas hydrate distributed off the shores of Japan is valuablernnatural gas resources for the country. To utilize these resources, it isrnnecessary to establish a gas production technology and investigaternsuitable conditions for production of methane gas from methanernhydrate reservoirs. Experimentally the production technology andrnsuitable conditions were investigated using the core samples which arernartificially synthesized in a laboratory or naturally drilled from methanernhydrate reservoirs. Although core-scale experiments give us thernreproducible results on how methane hydrate dissociates under variousrnconditions, a core-scale dissociation test in a laboratory canrndemonstrate the heat transport process. On the other hand, arndissociation of methane hydrates in an actual reservoir is dominated byrnthe material flow process. Namely, the natural gas production behaviorrnfrom methane hydrate reservoirs is dependent upon the size andrncharacteristics of reservoirs, such as temperature and permeability. Torncouple data obtained from core-scale tests with the results of field-scalernproduction tests, a large-scale production system in which dissociationrnexperiments under the similar conditions of the actual reservoir can bernconducted. In this paper, we describe the research objective of a largescalernproduction system for methane hydrate production testsrnestablished at the Methane Hydrate Research Centre of the NationalrnInstitute of Advanced Industrial Science and Technology (AIST)