摘要
疏松砂岩稠油油藏孔隙度大 ,胶结疏松 ,粘土矿物含量偏高。热采过程中 ,在微粒运移等多种机理的共同作用下容易产生地层伤害 ,造成地层渗透率下降 ,严重影响正常生产。该文以胜利油田的孤东九区、垦东 5 2 1、新滩油田为例 ,从地层伤害机理出发 ,在大量室内试验的基础上 ,研究了注入速度、注入气碱度、温度、浸泡周期及蒸汽凝析液等因素对疏松砂岩油藏造成的地层伤害。针对造成疏松砂岩油藏地层伤害的主要因素 ,提出了防膨及控制注入汽pH值等保护措施 ,为同类油藏的开发提供依据。
Heavy oil reservoir of loose sand is of large porosity, loose cementation and higher clay content. In the process of thermal recovery, many mechanisms, such as particle migration, may result in formation damage and permeability reduce. Furthermore, they can influence the ordinary production seriously. In examples of Gudong 9th area, Kendong 521 block and Feiyantan oil field in Shengli oil field, formation damage mechanism is studied first. Then the formation damage to loose sand made by the injection rate, basicity of injected gas, temperature, soak cycle and steam condensed liquid and so on is studied on the basis of a large number of laboratory experiment. Some protection measures such as anti-expansion and controlling pH value of the injected steam have been pointed out, which provided the basis of developing the same type of oil reservoir.