渤海K油田电潜泵化学解卡技术研究与应用

针对渤海K油田电潜泵泵卡影响生产且物理解卡不彻底的问题。分析了渤海K油田电潜泵结垢是泵卡主因，垢样主要由胶质、沥青质和碳酸钙镁、铁垢以及钡锶垢组成；采用低浓度的盐酸体系，具有多级电离、缓速性的多氢酸体系和以螯合剂为主的解堵体系的化学解卡技术思路，对电潜泵堵塞物中的无机垢进行酸洗、浸泡；形成了由钙镁垢体系、盐酸体系和多氢酸体系组成的多功能性化学段塞，并开展了垢样溶蚀性评价和部件腐蚀性评价。结果表明化学解卡技术配套体系对现场垢样溶蚀率高，同时对电缆、胶筒等电潜泵部件没有腐蚀风险。该技术在渤海K油田应用16井次，解卡成功率100%,启泵累产油7×10⁴ m³,增产效果显著，为渤海油田提供了一种高效、安全、经济的电潜泵化学解卡技术。

Research and Application of Chemical Stuck Removal Technology of Electric Submersible Pumps in Bohai K Oilfield

In order to solve the problem that the electric submersible pump(ESP) stuck pump in Bohai K oilfield which affects the production and the physical stuck removal is not complete. It has been analysised that the scaling of ESP in Bohai K oilfield is the main cause of stuck pump. The scaling samples are mainly composed of colloidal asphaltene, calcium magnesium iron carbonate scale and barium strontium scale. The chemical stuck removal technology of low concentration hydrochloric acid system, multi-stage ionization, retarded multi hydrogen acid system and chelating agent based deblocking system was adopted to pickling and soaking the inorganic scale in the plug of ESP. A multifunctional chemical slug composed of calcium magnesium scale system, hydrochloric acid system and polyhydric acid system was formed, and the dissolution and corrosion evaluation was carried out for scale samples and components of ESP, respectively. The results show that the supporting system of chemical stuck removal technology has high dissolution rate for scale samples on site, and has no corrosion risk for ESP components such as cables and rubber cylinders. The technology has been applied in 16 wells in Bohai oilfield, the success rate of releasing stuck is 100%, and the cumulative oil production is 7 ×104 m3. It provides an efficient, safe and economical chemical stuck removal technology for ESP in Bohai oilfield.