渤海某油田含聚污泥清洗技术研究与应用

Research and Application of Cleaning Technology of Polymer-containing Sludge in An Oilfield of Bohai Sea

渤海某油田为注聚油田,受效井产出液含有聚合物,聚合物与原油重质组分、泥砂微粒、金属离子和现场处理药剂共同作用,各组分缠绕包裹,形成含聚污泥,吸附在管道内壁造成管道缩径。根据含聚污泥形成机理和清洗目的,筛选出一种含聚污泥清洗体系,该体系由氧化剂、缓蚀剂和螯合分散剂复配而成。实验结果表明,清洗体系对含聚污泥进行浸泡溶解,在温度60℃、清洗时间24h、固液比为1∶20条件下,能有效溶解含聚污泥,溶解率为72%。清洗体系残液排放量基于产液在1%以下,对现场破乳剂破乳效果无影响;残液排放量基于污水在0.1%以下,对现场清水剂清水效果无影响。现场施工中,将清洗体系加热后注入气浮入口管道中,采用浸泡方式并采用电伴热保温。结果表明,清洗体系能有效缓解管线缩径堵塞情况,有利于油田现场的高效运行。

An oilfield in Bohai Sea is developed by polymer injection.The polymer is contained in the produced liquid from response wells,which plays roles with heavy component of crude oil,microparticles of mud and sand,metal iron and field treatment agents.And then polymer-containing sludge is formed through wrapping of each above component,and its absorption on the inner wall of the pipeline results in hole shrinkage of the pipeline.According to forming mechanism and cleaning goal of the polymer-containing sludge,a cleaning system of the polymer-containing sludge is selected that is composed with oxidant,corrosion inhibitor and chelating dispersant.The experimental results show that the cleaning system can be used to soak and dissolve the polymer-containing sludge.Under the conditions of temperature of 60 ℃,cleaning time of 24h and solid-liquid ratio of 1∶20,the dissolution rate of the polymer-containing sludge is 72%.When the discharge amount of residual liquid in the cleaning system is less than 1% based on the produced liquid,there are no effect on the demulsification effect of the on-site demulsifier.When the discharge amount of residual liquid is less than 0.1% based on the sludge,there are no effect on the on-site water clarifier.During the on-site operation,the cleaning system is heated and injected into the air float inlet pipeline.The method of soaking and electric heat insulation is adopted.The results show that the cleaning system can effectively alleviate the pipeline shrinkage and blockage,which is beneficial to the efficient operation of the oilfield.