河南油田聚合物驱地层堵塞机理研究

STUDY ON FORMATION PLUGGING MECHANISM IN HENAN OILFIELD POLYMER FLOODING BLOCK

针对河南油田注聚区面临的地层堵塞问题,进行了污水及污水配制聚合物的长岩心注入性试验,分析了影响聚合物注入性的各个因素及堵塞机理。结果表明:由于水质不合格造成了河南油田注聚区块污水对岩心的伤害;影响堵塞程度的主要因素有注入速度、岩石渗透率及聚合物浓度;注入速度一定时,岩石渗透率越小,注入浓度越高,吸附滞留量越大,堵塞也越严重;且在一定注入速度范围内,速度对渗透率大的岩心影响较小,而对于渗透率小的岩心,随注入速度的增加,吸附滞留量增大,堵塞在深部并随注聚过程的深入而加剧。

Aiming at the problem of formation plugging in Henan Oilfield polymer flooding block,the long core test with sewage and polymer made of sewage was carried out,and the formation plugging mechanism and the factors which influence the injectivity of polymer were analyzed.The results indicated,the unqualified injection water quality cause the damage to core in Henan Oilfield polymer flooding block;the main reasons which affecting polymer flooding formation plugging include injection rate,the rock permeability and the polymer concentration.In certain injection rate,the lower of rock permeability is,the higher injection concentration is,the more adsorption and the more seriously plugging is.In a reasonable range of injection rate,the affection of speed on the higher permeability core is light,to the lower permeability core,as injection rate increase,the adsorption quantity becomes bigger,it occurs plugging in deep,with the polymer injection process,the plugging become more seriously.