Research On Application Of Polymer Microspheres For Profile Control And Flooding In Offshore Oilfield

In the process of water injection in oilfield offshore, because of the crude oil viscosity is high, the reservoir heterogeneity, within and between the layers of the contradictions are becoming increasingly prominent. To improve the development effects of the water injection, increase the sweep factor, need to use the in-depth profile control method in the injection well.At present in depth profile control methods applied in the oilfield of domestic and abroad have different characteristics and conditions..In this paper, we select polymer microspheres as the profile control material to achieve the object. By means of the static experiment and association with the reservoir conditions of the candidate, three polymer microspheres of different cement way and dimensions are selected from dozens of the candidates. Result of the experiment shows that: the three different polymer microspheres can expansion to dozens of micron,micron,hundred s of Nanometer and the time is 20~30 days; different dimensions of the polymer microspheres take effects to the scale of the permeability under the ground correspondingly, increase the efficiency of the water flooding, and draw on the oil in the low permeability zone; at the condition of the object oilfield, the polymer microspheres can enhance the high permeability zone to the value of 80%, and the whole recovery can achieve to exceeding 20%; at the same time, the different dimensions of the polymer microspheres generates a overlay effect, which may reach a better result. We also studied the proper way of the injection through the experiment, the result shows that the high concentration slug has higher shut off capacity, which has a good effect to plug the cross flow channel under the ground; the low concentration slug has higher profile control ability in the internal layer and a longer function time. At last, the paper provides a right slug pack for the object well group.The experiment in the object oilfield proved that, profile control and flooding with polymer microspheres is a suitable technology for oilfield of the sea, for now,it has acquired a good application effect.