摘要
注水开发是油田常用的提高采收率的方式之一,但注入水经过联合站处理后,经注水站输送至各个配水间及单井井口的过程中,注水管线结垢堵塞严重,呈现出管线有效内径减小,流体输送效率降低,注入压力升高等系列现象。为解决该问题,以杏子川油田某联合站沿程注水管垢为研究对象,运用X射线衍射仪确定垢样类型,结合注水工艺中不同节点的污水水样与配伍性实验,分析引起管线结垢的原因,针对结垢特征,通过静态阻垢法开展了阻垢剂优选与评价实验。研究结果表明:长2层产出的回注水含有大量的Ca^(2+)和HCO_(3)^(-),自身存在严重的结垢趋势;同时,若水处理后悬浮物含量不达标,则会与CaCO_(3)沉淀相互作用,形成以CaCO_(3)为主、含有少量SiO_(2)和硅酸盐的垢物。通过实验优选出绿色环保的聚合物类阻垢剂并确定其最佳使用浓度。在阻垢剂浓度为60 mg/L时,现场注入水的阻垢率达到91.62%,据此给出阻垢剂现场加药措施,有效解决了油田水质结垢的问题,也为同类型油田回注水管线现场防垢提供一定的技术参考。
Water injection development is one of the commonly used ways to enhance oil recovery in oilfields.However,during the process of the injection water being treated by the united station and transported to each water distribution room and single well wellhead,the scale and blockage of the water injection pipeline are serious;it shows a series of phenomena,such as the decrease of the effective inner diameter of pipelines,the decrease of the fluid transmission efficiency,and the increase of the injection pressure.In order to solve this problem,this paper takes the scale formation of water injection pipelines in a united station of Xingzichuan Oilfield as the research object and uses X-ray diffractometer to determine the type of scale sample.Sewage water samples at different nodes in water injection process and compatibility tests were combined,and the causes of pipeline scaling were analyzed.According to the scale characteristic,the optimization and evaluation experiments of scale inhibitors were carried out using the static scale inhibition method.The research results indicate that the reinjection water from Chang2 contains a large amount of Ca^(2+)and HCO_(3)^(-),and there is a serious tendency for scaling on its own;at the same time,the suspended solids would interact with CaCO_(3)precipitation to form a scale mainly composed of CaCO_(3)and containing a small amount of SiO_(2)and silicates if their contents do not meet the standard after water treatment.Green and environmentally friendly polymer scale inhibitors were selected and their optimal concentration was determined through experiments.The scale inhibition rate of on-site injected water reached 91.62%at scale inhibitor is 60 mg/L.Based on this,on-site dosing measures for scale inhibitors were proposed,which can effectively solve the problem of oilfield water scaling;it also provides a certain technical reference for on-site scale prevention in the same type of oilfield reinjection water pipeline.
作者
王苗苗
韩龙飞
艾先婷
王祎璠
兰晓龙
高楠
WANG Miaomiao;HAN Longfei;AI Xianting;WANG Yifan;LAN Xiaolong;GAO Nan(Research Center for Exploration and Development Technology of Yanchang Oilfield Limited Company,Shaanxi Yan’an 716000,China)
出处
《非常规油气》
2024年第6期100-107,共8页
Unconventional Oil & Gas
基金
国家自然科学基金项目“多场耦合条件下甲烷/二氧化碳在页岩非均质储层中的动力学特征研究”(41772150)。
关键词
注入水
管线结垢
碳酸钙垢
阻垢剂
阻垢效果
inject water
pipeline scaling
calcium carbonate scale
scale inhibitor
scale inhibition effect
