黑山梁油区储层敏感性及解堵作用研究

Study on Reservoir Sensitivity and Unplugging in Heishanliang Oil Area

黑山梁油区为典型的特低渗油藏,储层渗透率低。本文针对注水过程和压裂改造过程中产生的水锁现象和近井地带污染导致的注水井注水压力升高、注水能力差的问题,在储层敏感性分析的基础上,采用研制的缓速酸在HSL区块进行了分层解堵试验。研究结果表明:①储层主要表现为中等偏弱速敏、弱水敏、中等偏强酸敏、弱碱敏;②多氢酸体系对石英和黏土的缓速性好,室内溶蚀时间达到10~12 h,同时对金属离子具有较好的螯合能力;③具有良好的解堵效果,使注水井单井日注水量由原来的注不进提高到目前的5~6 m 3,且有效期达到6个月以上,改善了吸水剖面。以上研究成果对国内类似油藏注水解堵具有重要的指导和借鉴作用。

Heishanliang oilfield is a typical low permeability reservoir,the reservoir permeability is low,in view of the water injection process and the fracturing process of water lock phenomenon and the pollution caused by the near wellbore area of injection wells water injection pressure,injection ability difference,on the basis of reservoir sensitivity analysis,the use of the retarded acid stratification in an HSL block broken down test.The results show that:①The reservoir is mainly characterized by medium weak velocity sensitivity,low water sensitivity,medium strong acid sensitivity and weak alkali sensitivity.②Polyhydrogen acid system has good retargeting property to quartz and clay,indoor dissolution time reaches 10~12 hours,and has good chelating ability to metal ions.③It has a good anti-plugging effect,which increases the daily water injection volume of the injection well from the original non-injection to the current 5~6 m 3,and the validity period reaches more than 6 months,and improves the water absorption profile.The above research results have important guidance and reference for similar reservoirs in China.