聚驱分子膜防堵剂的研制及应用

Development and Application of A Molecular Film Blocking Preventing Agent for Polymer Flooding

聚合物驱油技术在推广应用过程中出现注入压力上升的现象。部分井出现注入困难的问题,主要 原因是聚合物在地层中的吸附与滞留,采用目前的压裂与化学解堵技术治理有效期都相当短。聚驱分子 膜防堵剂由单分子两季铵盐、洗油剂、螯合剂组成,其主要防堵原理为:注入地层后洗去储层表面油膜 并吸附在岩层表面,形成单分子膜,膜的形成可大大减少随后注入的聚合物吸附,螯合剂能与地层中高 价阳离子反应,生成稳定物,防止其与聚合物交联,生成堵塞物。室内防堵评价试验表明,注聚后分子 膜防堵剂可减少压力升由0．15MPa。现场试验证明,采取防堵措施的注聚井注聚后平均单井注入压力上 升幅度低于没采取措施的注聚井1．3MPa。

In Daqing Oilfield, where polymer flood programs are performed, the injection pressure of the polymer injection wells is risen, part of them are difficult for injection. The key reason is found that HPAM absorbs on the reservoir rocks. The present hydrofracturing or chemical block removal for improving injection of wells is effective shortly. Agent of preventing reservoir (APRF) from blocking is composed both of an organic diammonium salt and other surface and in-terfacial tension agent. The functioning mechanism involved can be described as follows: block removal agent adsorbs on the reservoir rocks to form deposition film by its properties after the reservoirs are flooded continuously, then HPAM solution is injected to the reservoirs, amount of HPAM absorbed is largely reduced because the deposition film is existed. The deposition film formed by APRF protects polymer injection wells and reduces the polymer infection pressure.