低渗油层结垢分析及对策研究

结垢是油田注水普遍存在的问题,严重影响油田的正常生产,对此以新疆某结垢井区为例开展结垢机理分析和防垢技术研究。通过荧光光谱仪和电镜扫描分析垢样,结合水质分析和结垢趋势预测可知垢物以锶钡垢为主,成垢的主要原因在于:地层水锶、钙离子含量高,较高矿化度的采出水逐渐在井筒内壁形成垢层,且地层水与回注污水配伍性差。采用化学阻垢结合工艺防垢的方法,通过清、污水混配防垢技术最大程度去除成垢SO42-离子,选用油井井下释放式的投加方式投加溶度为100 mg/L的KZG-01。利用岩心驱替实验模拟地层真实情况实验,结果表明该方法有较好的阻垢效果且有效期长,可以用于指导现场施工。

Analysis and Countermeasures of Low Permeability Reservoir Scaling

Scaling is a widespread problem of oilfield water injection,seriously affects the normal production of the oil wells in the area.In this paper,taking a scale well area in Xinjiang as an example,the scaling mechanism was analyzed,and the anti-scaling technology was studied.Scale samples were analyzed by fluorescence spectroscopy and scanning electron microscopy,and the water quality analysis and scaling tendency prediction were carried out.The results show that the scale is mainly strontium barium;the main reason is that the formation water contains a lot of strontium and calcium ions,produced water with high salinity gradually forms the scale layer in the shaft wall,and the compatibleness of formation water and reinjected sewage is poor.It's pointed out that chemical scale inhibition and process scale control should be combined,clear water and sewage mixed anti-scaling technology should be used to remove SO42-ions,100 mg/L solubility KZG-01 should be added by downhole release type dosing method.Core flood experiment was used to simulate the real situation of formation.The experimental results show that this method has a good inhibition effect and long valid period.