一种聚合物驱油受效井螯合解堵体系研究与应用——以渤海S油田为例

Study and application on a chelates removal technology for polymer flooding response wells: a case of Bohai S oilfield

关键词:  聚合物驱  油-聚-固复合堵塞物  螯合解堵  砂岩  海上油田

Key words:  polymer flooding  oil-polymer-solid composite blockage  chelating removal technology  sandstone reservoir  offshore oilfield

摘要:

针对常规解堵工艺体系无法有效解除聚合物驱受效井复合堵塞物的问题,运用宏观和微观实验分析得出复合堵塞主要由聚合物、原油等有机物与含铁固相、黏土矿物等无机物层层包裹、相互掺杂而形成。实验表明,螯合解堵剂能很好溶蚀复合堵塞物中的各个无机物组成成分,对聚合物降解效果优于酸液和除过氧化氢之外的氧化剂。通过在渤海S油田20井筒内复合堵塞物溶蚀与降解实验说明,该解堵体系能有效解除这种复合堵塞物。现场应用表明,螯合解堵剂解堵效果优于传统解堵体系。 

Abstract:

The response wells of polymer flooding can form complicated blockages, which can not be dissolved by conventional acid treatments. The macroscopic and microscopic experimental analysis show that the blockages are wrapped and doped by organic substances and inorganic substances, and the formers are polymers and crude oils, the latters are iron-containing solid phases and clay minerals. Laboratory experiments show that the inorganic parts of blockages can be dissolved by the chelates solution, and the chelates dissolution capacity of polymer is better than the acid and oxide except hydrogen peroxide. Experiments of dissolving blockages by chelates removal system in well 20 of Bohai S oilfield are implemented, which shows that the complicated blockages can be effectively removed. The application cases indicate that the chelates removal system is better than conventional acids treatment system.