OPERATIONAL AND RESERVOIR PARAMETERS INFLUENCING THE EFFICIENCY OF STEAM-ASSISTED GRAVITY DRAINAGE (SAGD) PROCESS IN FRACTURED RESERVOIRS

摘要: The Steam-Assisted Gravity Drainage (SAGD) process is a promising enhanced oil recovery (EOR) method for certain heavy non-fractured sandstones, but its applicability in naturally fractured reservoirs (NFR) has not been addressed yet. In this contribution the CMG-STARS module applied together with numerical model developed SAGD, which qualitatively validated previously published experiments. This was modified to double porosity medium investigate effect of reservoir parameters such as °API crude oil, matrix permeability, initial saturation and fractures departure on SAGD efficiency presence networked fractures. Besides, effects operational parameters, vertical distance between wells stacked configuration horizontal offset staggered scheme, have also studied. simulation results showed higher case compared conventional case. Lower smaller permeability lower reduced performance NFR. It observed that should be optimized, since top injection improves ultimate production can delayed bottom steam injection. same true well configuration, traversal longer causes rates. However, achievable after breakthrough into producer well, configuration.