Physical property response of peri-well sediments during cementing of gas hydrate-bearing sediments in conventional oil-gas wells in the South China Sea

In order to investigate the effect of cement slurry penetration during cementing in gas hydrate-bearing sediments. this study, hydrate bearing sediments Shenhu Area South China Sea is taken as research object, numerical simulation software TOUGH+HYDRATE used realistically reproduce process exothermic and by “continuous segmental simulation.” The physical properties response near well wall under different parameters sediment geological are studied. Results show that hydration rate has significant influence on decomposition degree area, when it higher than 0.21 J·(g·s) −1 , range completely decomposed. pressure difference affects depth, extent pressurization heat-up, which turn zones. addition, helpful increase pore phase equilibrium, but should be strictly controlled within window fracture pressure. Extending holding time expands heat-up zones, also delays onset decomposition. Higher saturation prevents weakens diffusion pressure, causes shrinkage makes zone. equilibrium environment directly determines resistance perturbation, with insignificant changes stable permeability transport efficiency fluid zone zone, peak sediment, from 1 100 mD 10 cm. porosity a less effects properties. This study valuable guide reference for operations.