The Evaluation Study Of Active Polymer System For Third Class Oil Layer In Xingbei Oilfield

In recent years, polymeric surface-active agent (living polymer) as a new type of flooding agent has been carried out a pilot test in Daqing oilfield. As the time of its occurrence is short, the studies about the properties and the flooding effect are few. Some problems encountered in pilot test are hard to explain and solve with current theory. For the actual need in the pilot, the author took the advantage of current reservoir engineering theory, instruments monitoring technology and physical analog method, studied a lot about its properties and the flooding effect. The results show that compared with molecular structure and clew size of polymer, polymeric surface-active agent molecules has"piece-mesh molecular"structure, molecular size is larger, the effect of increasing oil viscosity is better, but the transmission and migration ability is worse. It is different from the polymer, of which viscosity declined continuously, the viscosity of polymeric surface-active agent increases first and then decreases, which is similar to polymer gel. There is micro active substance in polymeric surface-active agent, which has stronger emulsifying and cleaning oil capability. The chromatographic fractionation not only influences the viscosity, but also arouses concentration monitoring error of producing fluid. The higher the concentration of polymeric surface-active agent is, the more volume of chemical agent is and the earlier the injection time, the more recovery increasing degree is. Slug dimensions and array mode will influence effect of increasing oil. The increasing oil effect of entire slug and slug array mode of that viscosity presents"high-middle-low"is the best, followed by slug array mode of that viscosity presents"middle-low-high"; that of slug array mode of that viscosity presents"low-middle-high"is the worst.