超低渗透油藏调驱一体化体系精细设计及评价

Fine design and evaluation of profile control and oil displacement system in ultra-low permeability reservoirs

实验区块长2储层纵向孔隙度和渗透率差异大,注水采收率低、稳产难度大,为改善这一状况,研制了预交联体膨颗粒-超低界面表面活性剂调驱一体化体系。研究表明,通过反向微乳液法制备的预交联体膨颗粒30 d的膨胀倍数为原来的15~20倍、抗压强度>2 MPa,封堵率>92.4%。通过多种功能表面活性剂复配而成的生化耦合超低界面表面活性剂,界面张力可降低至10-2mN/m,原油乳化降黏效率>65%,岩心驱油效果提升>13.0%。预交联体膨颗粒-超低界面表面活性剂体系可以充分发挥调剖和驱油综合性能,利用协同作用在高渗透岩心和低渗透岩心中分别提高采收率9.3%和18.1%。该体系用于超低渗透非均质油藏深部调驱一体化。

In the experimental field,the porosity and permeability of the reservoirs are different with low water injection rate,serious water channeling and difficult stable production.To improve this exploitation,the integrated system of pre-crosslinked expanded particles with ultra-low interface surfactant was developed.The results showed that the expansion ratio of the pre-crosslinked expanded particles prepared by reverse microemulsion method was about 15~20 times,compressive strength was more than 2 MPa,and the blocking rate was more than 92.4%.The interfacial tension can be reduced to 10-2mN/m,the emulsification and viscosity reduction efficiency of crude oil was more than 65%,and the effect of core flooding was more than 13.0%,which was composed of various functional surfactants.Pre-crosslinked expanded particle with ultra-low interface surfactant system can fully the comprehensive performance of profile control and flooding,and the cooperative mechanism of enhanced oil recovery in high-and low-permeability cores was increased by 9.3%and 18.1%,respectively.The integrated system is suitable for ultra-low permeability heterogeneous reservoirs of deep oil displacement.