| The use of foams for oil-recovery applications has been studied for more than thirty years and the technologies of polymer and chemical flooding have demonstrated great potential in field applications. The advantage of CO 2 Alkali Surfactant Polymer Foam (ASPF) flooding is the combination of the benefits of polymer, ASP and foam flooding in one process. Polymer could increase the stability and the carrying ability of foams, and alkali is beneficial in reducing interfacial tensions further than with surfactant only. Combined with pore space occupation of gas, the oil displacement efficiency can be greatly improved.; An ASPF foaming solution was formulated for a Western-Canada medium oil in a high salinity brine environment, and a series of core flooding tests have been conducted in a micromodel and in sand packs. The experimental results demonstrated very high oil recovery efficiency as a result of ASPF flooding. Direct visualization of the foam flow performance verified the displacement mechanisms in micromodel tests. |
