| Popis: |
Rospan International, a subsidiary of TNK-BP, is developing its Russkoe heavy-oil field located in the Yamalo-Nenets Autonomous District of Russia. Development of this field commenced with several pilot pads of horizontal wells completed with stand-alone sand-screens because of the unconsolidated sandstone formation. To increase oil recovery hot water flooding through horizontal injectors was employed, however because of high reservoir heterogeneity the injection profile was not uniform and this led to early water breakthrough and an inefficient waterflood, leaving unswept oil reserves. The remote location and harsh environment limited the use of the conventional production logging tools (PLT) for monitoring the injection profile. Because of this, Rospan International chose to install fiber-optic distributed temperature sensing (DTS) system in a ¼-inch control line attached to a stinger hung below the injection tubing along the reservoir section, post-completion, to determine the injection profile and optimize water flooding. This paper is describes the completion technology used to install the fiber in the horizontal injector and shows the data and results obtained. Numerical thermal models of the near-wellbore environment were used to analyze the shut-in cool-back and hot water velocity injection DTS data to calculate the injectivity profile. Comparison of the inflow profile calculated from the DTS and PLT data proved the value of the installed optic fiber system for injection change monitoring over time and water flooding optimization for Russkoe oilfield. |
