To solve the problem whereby an oil reservoir with applicable boundaries of the current sand-inhibiting and water-control agent is unclear,a supramolecular sand-inhibiting and water-control agent PDKM was prepared usi...To solve the problem whereby an oil reservoir with applicable boundaries of the current sand-inhibiting and water-control agent is unclear,a supramolecular sand-inhibiting and water-control agent PDKM was prepared using acrylamide(AM),methacryloxyethyltrimethyl ammonium chloride(DMC),styrene(SM),and γ-methacryloyloxypropyltrimethoxysilane(KH570)as comonomers.The molecular structure of PDKM was verified by ^(1)H-NMR and FT-IR.On the basis of establishing an evaluation method that can screen the performance of sand-inhibiting agent at a flow rate of 100 mL/min,the oil reservoir applicable boundaries of PDKM were obtained through the evaluation of sand-inhibiting and water-control performance.The experimental results show that when the concentration of PDKM is 5000 mg/L,the oil reservoir conditions are temperature≤90℃,formation water salinity≤21,249 mg/L,the degree of sand production corresponding to slight sand production and particle migration,crude oil viscosity≤50 mPa⋅s,primary water flooding water cut≥75%,and formation permeability contrast≤2.The performance with respect to sand inhibiting and water control can all reach an excellent level.There-fore,the PDKM solves the problem whereby the applicability of the current sand-inhibiting and water-control agent is unclear,and provides direction for the selection of suitable products in the oilfield production site.展开更多
Friction properties of rock are closely connected with the anisotropy.The anisotropy of rock friction can provide a valuable assessment for geotechnical and geological engineering.In this study,the rotary friction tes...Friction properties of rock are closely connected with the anisotropy.The anisotropy of rock friction can provide a valuable assessment for geotechnical and geological engineering.In this study,the rotary friction tests were conducted to analyze the water effect on the friction property and the friction anisotropy of the four types of rock.The drilling response model(DD-model)was employed to characterize the rotary friction behavior of the rocks.The parameters of this model include the three types of friction parameters:1/ς,μ,and f,where 1/ςandμare constant,and f is a variable.A quantitative method is proposed for assessing the anisotropy of rock friction.The results of the rotary friction tests indicate that the relation between torque force and thrust force conforms to the DD-model.The changes of two friction constants 1/ςandμfrom dry state to water-saturated state suggest that the water effect on the friction strength of the rocks exhibits significant anisotropy.The friction strength determined by the friction variable f increases first,then decreases,and finally stabilizes with the increasing of depth.AIf is an anisotropy index calculated by the proposed method.The percentage difference of the average value of AIf between water-saturated and dry states shows the degree of the water effect on the friction anisotropy of the rocks,mudstone(MU)>granite(GR)>fine sandstone(FS)>argillaceous siltstone(AS).The quantitative model is hopefully constructed for characterizing the relation between the anisotropic friction strength of rock and the moisture state in future.展开更多
基金supported by the National Natural Science Foundation of China(General Program)(Grant No.52474071)the Provincial Key R&D Program of Shandong(2022CXGC020303)the financial support from the China Scholarship Council(TM Lei,Grant No.202406450004).
文摘To solve the problem whereby an oil reservoir with applicable boundaries of the current sand-inhibiting and water-control agent is unclear,a supramolecular sand-inhibiting and water-control agent PDKM was prepared using acrylamide(AM),methacryloxyethyltrimethyl ammonium chloride(DMC),styrene(SM),and γ-methacryloyloxypropyltrimethoxysilane(KH570)as comonomers.The molecular structure of PDKM was verified by ^(1)H-NMR and FT-IR.On the basis of establishing an evaluation method that can screen the performance of sand-inhibiting agent at a flow rate of 100 mL/min,the oil reservoir applicable boundaries of PDKM were obtained through the evaluation of sand-inhibiting and water-control performance.The experimental results show that when the concentration of PDKM is 5000 mg/L,the oil reservoir conditions are temperature≤90℃,formation water salinity≤21,249 mg/L,the degree of sand production corresponding to slight sand production and particle migration,crude oil viscosity≤50 mPa⋅s,primary water flooding water cut≥75%,and formation permeability contrast≤2.The performance with respect to sand inhibiting and water control can all reach an excellent level.There-fore,the PDKM solves the problem whereby the applicability of the current sand-inhibiting and water-control agent is unclear,and provides direction for the selection of suitable products in the oilfield production site.
基金sponsored by the National Natural Science Foundation of China(Grant nos.42177158,11902249,and 11872301)Key Research and Development project of Shaanxi Province(Grant no.2022SF-412)+4 种基金Education Bureau of Shaanxi Province Scientific Research Plan Projects of Shaanxi Education Department in China(Grant no.20JS093)Opening fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(Grants no.SKLGP2022K005)Higher Education Basic Science(Natural Science)Research Project of Jiangsu Province in China(Grant no.23KJD410002)Yangzhou Green Yang Golden Phoenix Plan(Grant no.2408008/022)Yangzhou Science and Technology Project(Grant no.YZ2021166).
文摘Friction properties of rock are closely connected with the anisotropy.The anisotropy of rock friction can provide a valuable assessment for geotechnical and geological engineering.In this study,the rotary friction tests were conducted to analyze the water effect on the friction property and the friction anisotropy of the four types of rock.The drilling response model(DD-model)was employed to characterize the rotary friction behavior of the rocks.The parameters of this model include the three types of friction parameters:1/ς,μ,and f,where 1/ςandμare constant,and f is a variable.A quantitative method is proposed for assessing the anisotropy of rock friction.The results of the rotary friction tests indicate that the relation between torque force and thrust force conforms to the DD-model.The changes of two friction constants 1/ςandμfrom dry state to water-saturated state suggest that the water effect on the friction strength of the rocks exhibits significant anisotropy.The friction strength determined by the friction variable f increases first,then decreases,and finally stabilizes with the increasing of depth.AIf is an anisotropy index calculated by the proposed method.The percentage difference of the average value of AIf between water-saturated and dry states shows the degree of the water effect on the friction anisotropy of the rocks,mudstone(MU)>granite(GR)>fine sandstone(FS)>argillaceous siltstone(AS).The quantitative model is hopefully constructed for characterizing the relation between the anisotropic friction strength of rock and the moisture state in future.
