单体地下聚合并交联形成凝胶——防止聚合物窜流的一种新方法

Impeding Premature Polymer Production from Polymer Flooding Reservoirs by Way of in-Situ Polymerization and Gel Formation

:孤岛油田由于长期注水开发 ,层内或层间非均质程度明显增强。聚合物溶液注入地层后遇到高渗透带或大孔道时 ,经常发生指进或窜流的现象 ,很快从油井中采出 ,使聚合物驱效果明显变差 ,并造成大量聚合物无效损失。本项目采用注入单体 +交联剂的方法 ,能够有效利用地下大量残留的聚合物溶液 ,提高地下聚合物溶液的粘度 ,堵塞出聚合物孔道 ,改变后续聚合物溶液流向 ,扩大聚合物驱的波及体积 ,提高聚合物驱的效果。

Premature polymer production in large quantities from polymer flooding reservoirs is a serious problem at Gudao, Shengli, and is owing to polymer channelling through substratial high permeable zones(HPZs), or passages. In this paper a noval technology of plugging HPZs to impede polymer channelling is presented: to squeeze into injection well a solution of monomer(3—8%), initiator, polymerization inhibilor, and organic crosslinker and these chemicals together with the polymer HPAM and Cr 3+ compound(in the case of crosslinking polymer flood) remained in reservoir formations react and form strong gel in situ and thus impede the polymer channellings. The formulation of this in situ polymerizable/gel forming fluid PFC, its performance properties and field uses for impeding polymer channelling in 4 injection wells are described.