In the process of gas hydrate drilling,the drilling fluid is easy to intrude into the formation and change the formation temperature,pressure and chemical conditions of the hydrate formation,leading to the decomposition of hydrates in the surrounding formation and instability of the wellbore.The problem of wellbore instability caused by hydrate decomposition during hydrate drilling in the South China Sea is analyzed and studied.A composite phase change material is prepared by using intelligent temperature control method,adsorbing and modifying n-alkanes with vermicular graphite.The results show that the prepared composite phase change material has good phase change latent heat performance,the phase change temperature is controllable in the range of 17-18℃,and the particle size can meet the basic requirements for effective recovery of screening particle size on site.It also has good compatibility with drilling fluid and is suitable for water-based drilling fluid system for hydrate reservoir drilling.
natural gas hydratetemperature control material,water-based drilling fluid
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维普
