Abstract: Along with oilfield water content rising, the scaling phenomenon is quite severely in the ground and gathering system.In view of the scaling characteristics of Xinjiang oilfield, Seven typical wells of three areas were selected.The scaling reason in oil well was studied by X-ray diffraction measurement to scale obtained from oilfield.Influences of environmental factors, such as time, temperature, pH value, concentration of scaling to scaling were investigated by EDTA titration method.The application efficiency of a novel complex scale inhibitor was evaluated by using the static scale inhibitor method.It is found that the scale of the oilfield is mainly composed of carbonate scale.The scaling kinetics changes suddenly at 9h.The raising temperature will decrease the solubility of the scale of CaCO₃ in the water.The higher the pH value is, the stronger the tendency formed of carbonate scale is.The raising concentration of Ca²⁺, Mg²⁺ and HCO₃^- is in favor of the formation of carbonate scale.Inhibition efficiency of the complex scale inhibitor composed of HX-1 and WAS with volume ratio 1:1 is more than 93.9%, which shows good application effect in the oilfield.

Key words: scaling, EDTA titration method, static scale inhibitor method, scale inhibitor

摘要： 油田进入高含水期,地面及集输系统的结垢问题日趋严重,针对新疆某油田的结垢特点,本文选取3个区块7口典型井,通过XRD测试油井结垢的主要产物,分析了结垢的原因,采用EDTA滴定法考察了时间、温度、pH值、成垢离子浓度对结垢的影响规律,同时用静态阻垢法评价了一种复配型阻垢剂的应用效果。结果表明:该油田结垢以CaCO₃为主;结垢动力学在9h发生突变;随着温度升高,碳酸钙垢在水中的溶解度降低;pH值越高,形成垢的趋势越强;Ca²⁺、Mg²⁺和HCO₃^-浓度增加,结垢均增加,对垢的形成有一个促进作用。添加体积比为1:1的HX-1/WAS复配阻垢剂后,阻垢率达到93.9%以上,使用效果优良。

关键词: 结垢, EDTA滴定法, 静态阻垢法, 阻垢剂