岐口17-2油田注水悬浮物组分分析及控制措施

Analysis and control measures of suspended matters in Qikou 17-2 oilfield injection water

关键词:  岐口17-2油田  注水  水质  悬浮物  组分分析  措施 

Key words:  Qikou17-2 oilfield  injection water quality  suspended matters  component analysis  control measures

摘要:

悬浮物是油田注水的主要控制指标,超标则易堵塞注水井渗滤端面及渗流孔道,造成注水压力上升,注水量下降,降低油田的注水效果。利用岩矿分析手段对岐口17-2油田注水悬浮物进行剖析,并提出解决悬浮物含量超标的方法及解除其堵塞的控制措施。研究表明,清水、污水混合注入后,悬浮物质量浓度相比混合前增加1.8 ～5.1 mg/L,原因主要是清水与污水不配伍,流程较脏。通过加入30 mg/L的防垢剂95% ATMP,可抑制混合水样中Ca²⁺、Mg²⁺ 等结垢离子浓度的降低以及悬浮物含量的增加,在井口加装过滤器可进一步稳定注水水质。注水中悬浮物组分是以铁硫化合物为主的腐蚀产物和以硅铝元素为主的地层矿物,含少量以钙镁为主的碳酸盐垢,颗粒粒径主要集中在5 ～15 μm之间。通过加强对含铁硫化合物的酸化力度,加大前置液盐酸的用量,可保证对地层堵塞物的深度溶解,改善注水效果。 

Abstract:

Suspended solid is the main control index of oilfield injection water,the exceeded suspended solids can easily block the leakage end face and seepage pores of injection wells, which cause water injection pressure increasing and injection rate declining, in a word, the effect of water injection is worse. Through the rock ore analysis to analyze the QK 17-2 oilfield water injection suspended solids, and put forward the solution to high suspended solid content and control measures of removing the blockage. Study shows that suspended solids content increases by 1.8 to 5.1 mg/L after the injection of fresh water and sewage water, the main reason is that fresh water and sewage water is not compatible, and the process is dirty. By the addition of 30mg/L antiscale 95% ATMP, the concentration of Ca²⁺, Mg²⁺ in the mixing water samples as well as the increase of suspended solids can be inhibited, installation of filter at the wellhead can further stabilize the quality of injection water. The main components of suspended solids in injection water are corrosion products of iron-sulfur compounds and formation mineral based on silicon and aluminum, which contain a small amount of calcium and magnesium-based carbonate, the main particle size is from 5μm to 15μm. By strengthening the acidification efforts of iron-sulfur compounds and increasing the dosage of hydrochloric acid pre-liquid, the blockages can be dissolved well and the water injection effect can be improved.