油房庄油田老区地面集输系统腐蚀与结垢机理研究

Study on Corrosion and Scaling Mechanism of Surface Gathering System in the Old District of Youfangzhuang Oilfield

摘要: 油房庄油田老区已进入开采中后期，区块部分地面集输、注水系统腐蚀、结垢严重，影响到了油田的正常生产。以油房庄老区腐蚀结垢方面存在的实际问题为重点，对其腐蚀结垢机理进行了系统的研究。油房庄老区采出液矿化度较高，不同层系间均存在一定程度的结垢，配伍性较差，不同层位的采出液在集输系统混合时，易导致集输站点总机关及加热炉盘管结垢；垢样以硫酸钙垢为主，并含有少量碳酸锶垢和腐蚀产物。油房庄老区采出水中Cl−质量浓度较高(平均值25874 mg/L)，主要以盐卤腐蚀为主因，并伴有垢下腐蚀。故油房庄老区应以防硫酸盐垢和盐卤腐蚀为主，优选和复配相应的缓蚀阻垢药剂。

Abstract: The old region of Youfangzhuang Oilfield has entered the middle and later stages of oil production. There existed serious corrosion in part of the surface gathering system and water injection system with serious scaling in the block, which affected the normal production of the oilfield. Based on the practical problems of corrosion and scaling occurring in the old region of Youfangzhuang Oilfield, the mechanism of corrosion and scaling was systematically studied. Salinity was high in the produced fluid, and there existed different levels of scaling between different layers and compatibility was poor. When the produced fluids from different layers were mixed in the gathering and transmission system, it was easy to cause scaling in the general station of the gathering system and the scaling in the coiled pipes of the heating furnace. The scaling samples were mainly of calcium sulfate, and contained a small amount of strontium carbonate scale and corrosion products. The oil produced in the old oil region contained high concentration of Cl− ions (average 25874 mg/L); it was mainly salt and brine corrosion, and was accompanied by under-scale corrosion. Therefore, the old Fangyouzhuang Region should be mainly anti-sulfate scale and brine corrosion, and the corresponding corrosion and scale inhibitors should be selected and compounded.