Enhanced Oil Recovery Technology After Polymer Flooding

Polymer flooding has been realized industrial application in China, especially in the Daqing oil field, laboratory and field practices have achieved good results. But after polymer flooding, nearly half geological reserves are still not produced, how to further improve recovery after polymer flooding is a pressing problem.Remaining oil distribution after polymer flooding scattered , complex reservoir conditions, In the past, two-dimensional model (the three inhomogeneous rectangular core and homogeneous plane model) was uesd to research physical simulation experiments after polymer flooding,and cannot resemble with the reservoir, can not fully reflect the difference of the sweep efficiency in a variety of enhanced oil recovery method after polymer flooding. This study uses a large three-dimensional physical model, research remaining oil after polymer flooding. on this basis to optimize further improve recovery after polymer flooding in this research.Through these research, give the remaining oil distribution characteristics after polymer flooding, optimize the best further enhance oil recovery method after polymer flooding, quantify producing performance of different oil layers of every further enhance oil recovery methods after polymer flooding, offers clearly the differences in to expand swept volume and to improve oil displacement efficiency among a variety of further enhance oil recovery method after polymer flooding; the findings will provide a theoretical basis for application of further enhance oil recovery method after polymer flooding.Further enhance oil recovery methods after polymer flooding results showed that: to further reduce the mobility ratio is further enhanced oil recovery polymer flooding prerequisite; On the condition of reducing mobility ratio, further enhance oil recovery method after polymer flooding should adhere to the principle of.improving oil displacement efficiency;In different further enhance oil recovery methods after polymer flooding, the best approach would be to further expand sweep extent in low permeable layer,and to improve oil displacement efficiency in the high permeability layer; Under this experiment circumstances, We recommend that further enhance oil recovery optimal method after polymer flooding is SP,main slug is 0.3PV, polymer concentration of 1400mg / L, surfactant concentration of 0.3%; protective slug is 0.2PV, polymer concentration of 1400mg / L.