摘要
针对长庆低渗油层吸水剖面不均匀、调剖剂难注入且易剪切失效等问题,在有机铬弱凝胶调剖剂中添加延缓剂,保证其长时间保持低黏状态,终凝后能高黏度封堵,同时评价了聚合物浓度、交联剂和延缓剂的质量分数、温度、pH值、矿化度对成胶性能的影响,并进行了凝胶体系的抗剪切性和室内岩心评价实验。研究表明:50℃下,有机铬弱凝胶的成胶时间在1～12 d可调,其适用于pH值为6～11、矿化度低于13 000 mg/L的低渗油层;有机铬凝胶体系初凝黏度低于300 mPa.s,注入压力小于8 MPa,剪切速率在2～75 s-1时凝胶稳定性良好,终凝后黏度高于500 mPa.s,与岩心有良好的配伍性,封堵率高于92%,适合低渗油层深部调剖作业。
In view of the problems that exist in water injection in low permeability reservoirs of Changqing Oilfield,such as no uni-form injection profile,difficult injection and easy failure by shear,retardants are added in organic chromium weak gel profile control agent to keep the low viscosity for a long time and to have high plugging strength after final setting;the effect of the mass fraction,temperature,pH value and salinity of polymer concentration,cross linking agent and retarding agent on gel properties is evaluated;and the experiments of shear resistance and lab core of the gel system are conducted.The studies show that under 50℃,the adjustable gelling time of organic chromium weak gel is 1 to 12 days,which is applicable to low permeability reservoirs with PH value being 6 to 11 and salinity being 13 000 ppm;the initial gelling viscosity of organic chromium gel system is less than 300mPaos,injection pressure is less than 8MPa,stability is good when shearing rate is 2 to 75s-1,final setting viscosity is more than 500mPaos,it has good compatibility with core,plugging ratio is higher than 92% and it's suitable for low permeability reservoir deep profile control.
出处
《特种油气藏》
CAS
CSCD
北大核心
2013年第3期114-117,156-157,共4页
Special Oil & Gas Reservoirs
基金
黑龙江省自然科学基金委员会"超支化阳离子聚合物分子设计与净水机理研究"基金项目分支项目(B200912)
关键词
深部调剖
低渗油层
有机铬弱凝胶
低渗油层
长庆油田
deep profile control
low permeability reservoir
organic chromium weak gel
Changqing Oilfield
