After steam discharge in heavy oil reservoirs,the distribution of temperature,pressure,and permeability in different wells becomes irregular.Flow channels can easily be produced,which affect the sweep efficiency of th...After steam discharge in heavy oil reservoirs,the distribution of temperature,pressure,and permeability in different wells becomes irregular.Flow channels can easily be produced,which affect the sweep efficiency of the oil displacement.Previous studies have shown that the salting-out plugging method can effectively block these channels in high-temperature reservoirs,improve the suction profile,and increase oil production.In the present study,the optimal dosage of the plugging agent is determined taking into account connection transmissibility and inter-well volumes.Together with the connectivity model,a water flooding simulation model is introduced.Moreover,a non-gradient stochastic disturbance algorithm is used to obtain the optimal plugging agent dosage,which provides the basis for the high-temperature salting-out plugging agent adjustment in the field.展开更多
Inspired by the viscoelastic displacement theory,a product called preformed particle gel(PPG)is developed as conformance control agent to enhance oil recovery and control excess water production.The migration law of P...Inspired by the viscoelastic displacement theory,a product called preformed particle gel(PPG)is developed as conformance control agent to enhance oil recovery and control excess water production.The migration law of PPG suspension in porous media is related to its deep profile control and displacement capability.Laboratory experiments indicate that PPG suspension has good viscosity increasing,and the apparent viscosity decreases with the increase of shear rate.PPG suspension is mainly elastic,and its network structure makes it have certain shear stability.PPG particles realize migration in porous media in the way of“accumulation and blockage/pressure increase/deformation and migration”.When the ratio of the PPG particle size to the pore throat diameter d ranges from 35.52 to 53.38,the particles can match through the porous medium.When the permeability difference of the parallel model is 5,PPG suspension has the highest profile improvement rate,69.10%.PPG suspension can adjust the planar heterogeneity,and increase the oil recovery rate by 20.75%.The PPG suspension can effectively start“cluster"、“film”and“blind end residual oil”,and has a high oil washing efficiency.The core NMR T2 spectrum shows that PPG suspension mainly reduces oil saturation in mesopores and macropores.After PPG flooding,the EOR capacity of small pores is the highest,39.11%.展开更多
随着石油资源的日益紧张,提高油田开采效率成了石油行业面临的主要挑战。选用3种不同的化学剂(PAM、SDBS、PAA)并通过测定岩心渗透率和油水界面张力进行驱油效率实验。实验结果显示,PAA在提高岩石渗透率方面表现最为突出,从130.14 m D...随着石油资源的日益紧张,提高油田开采效率成了石油行业面临的主要挑战。选用3种不同的化学剂(PAM、SDBS、PAA)并通过测定岩心渗透率和油水界面张力进行驱油效率实验。实验结果显示,PAA在提高岩石渗透率方面表现最为突出,从130.14 m D增加到212.43 m D,增幅为63.2%,而SDBS则在降低油水界面张力方面表现最佳,从38.92 m N·m^(-1)降至21.00 m N·m^(-1),降低了46.2%。此外,在中温(40℃)和中压(20 MPa)以及适中的注入流量(100 L·min^(-1))下,驱油效率达到最优。化学剂在改变岩石孔隙结构及降低油水界面张力方面的作用,共同促进了油水流动性的提升,从而显著增强了整体的驱油效果。研究结果对于指导实际油田作业中化学剂的选择和应用具有重要的参考价值,为油田开发提供了新的视角和方法。展开更多
基金supported by China Postdoctoral Science Foundation(No.2021M702304)Shandong Provincial Natural Science Foundation Youth Fund(No.ZR2021QE260).
文摘After steam discharge in heavy oil reservoirs,the distribution of temperature,pressure,and permeability in different wells becomes irregular.Flow channels can easily be produced,which affect the sweep efficiency of the oil displacement.Previous studies have shown that the salting-out plugging method can effectively block these channels in high-temperature reservoirs,improve the suction profile,and increase oil production.In the present study,the optimal dosage of the plugging agent is determined taking into account connection transmissibility and inter-well volumes.Together with the connectivity model,a water flooding simulation model is introduced.Moreover,a non-gradient stochastic disturbance algorithm is used to obtain the optimal plugging agent dosage,which provides the basis for the high-temperature salting-out plugging agent adjustment in the field.
基金The work was supported by the National Natural Science Foundation of China(No.51674208)Sichuan Provincial Key Labo-ratory of Applied Chemistry for Oil and Gas Field Open Fund(YQKF202010)Southwest Petroleum University College Students Open Experimental Fund(2020KSZ33001,2020KSZ04047).
文摘Inspired by the viscoelastic displacement theory,a product called preformed particle gel(PPG)is developed as conformance control agent to enhance oil recovery and control excess water production.The migration law of PPG suspension in porous media is related to its deep profile control and displacement capability.Laboratory experiments indicate that PPG suspension has good viscosity increasing,and the apparent viscosity decreases with the increase of shear rate.PPG suspension is mainly elastic,and its network structure makes it have certain shear stability.PPG particles realize migration in porous media in the way of“accumulation and blockage/pressure increase/deformation and migration”.When the ratio of the PPG particle size to the pore throat diameter d ranges from 35.52 to 53.38,the particles can match through the porous medium.When the permeability difference of the parallel model is 5,PPG suspension has the highest profile improvement rate,69.10%.PPG suspension can adjust the planar heterogeneity,and increase the oil recovery rate by 20.75%.The PPG suspension can effectively start“cluster"、“film”and“blind end residual oil”,and has a high oil washing efficiency.The core NMR T2 spectrum shows that PPG suspension mainly reduces oil saturation in mesopores and macropores.After PPG flooding,the EOR capacity of small pores is the highest,39.11%.
文摘随着石油资源的日益紧张,提高油田开采效率成了石油行业面临的主要挑战。选用3种不同的化学剂(PAM、SDBS、PAA)并通过测定岩心渗透率和油水界面张力进行驱油效率实验。实验结果显示,PAA在提高岩石渗透率方面表现最为突出,从130.14 m D增加到212.43 m D,增幅为63.2%,而SDBS则在降低油水界面张力方面表现最佳,从38.92 m N·m^(-1)降至21.00 m N·m^(-1),降低了46.2%。此外,在中温(40℃)和中压(20 MPa)以及适中的注入流量(100 L·min^(-1))下,驱油效率达到最优。化学剂在改变岩石孔隙结构及降低油水界面张力方面的作用,共同促进了油水流动性的提升,从而显著增强了整体的驱油效果。研究结果对于指导实际油田作业中化学剂的选择和应用具有重要的参考价值,为油田开发提供了新的视角和方法。
