Design Strategies for Improved Conformance Using Polymer Gels
Kantzas, A., Burger, D., Pow, M., Cheung, V. and Mourits, F.
CIM Paper No 94-27, presented at the 45th Annual Technical Meeting of the Petroleum Society of CIM, Calgary, Alberta, June 12-15, 1994.
J.Can.Pet.Tech., 38(13), December 1999.
The possibility of using polymer gels for improved conformance in the treatment of producer wells has been evaluated using computer simulation. A radial model was built and used to test a variety of immiscible displacement conditions. The tests included water influx in a layered clastic reservoir with and without segregation between layers, simultaneous water and gas coning in a uniform carbonate reservoir, and simultaneous water and gas channelling in a fractured carbonate reservoir. The gel placement was modelled by altering the permeability, or the relative permeability, of the affected blocks according to experimentally determined values. Reverse coning was also evaluated for the case of simultaneous water and gas coning.
This preliminary design work has proved that utilization of polymer gels in producers is favoured in clastic reservoirs when there is segregation between layers. It also proved that gels have little value when implemented in a uniform carbonate reservoir producing under high water/oil ratio. Gel placement extended production well life by significantly reducing water/oil ratios and gas/oil ratios, but cumulative oil production did not increase in proportion to well life. Injection of a plugging agent around the perforations can be detrimental to oil production if the plug is too large. Finally, reverse coning was found to be more effective than gel placement for the case of simultaneous water and gas coning.