Implementation of a Fit-for-Purpose Cementing Technology for the First Gas Hydrate Production in Japan
JOGMEC (Japan Oil, Gas and Metals National Corporation) was planning for
the first offshore production test of methane hydrates in the eastern Nankai
Trough off of Japan. The test needs one production well and three temperature
monitoring wells to study the dissociation performance of methane hydrate
formations. Cementing these types of wells needed to have a specific cementing
technology fit for deepwater shallow unconsolidated formations subject to
subsidence and methane hydrate-bearing formations.
A project was initiated in 2011 with the objective being to design and
qualify a cement slurry system fit for deepwater shallow unconsolidated
formations subject to subsidence and methane hydrate-bearing formations. Based
on extensive laboratory and full-scale testing, a cement technology was
qualified by the service company and approved by JOGMEC to be the optimum
solution for this unique project.
This paper will describe the full-scale and extensive laboratory testing
used to qualify the cement technology fit for this application and the
different stages that create sufficient wellbore stability for the drawdown
during the production test. In addition, real-time temperature data
interpretation will be presented showing the cement hydration in these wells
after placement. Case histories of the three wells will be presented.