长庆油田庆二联采油污水回注处理研究

Study on the re-injection treatment of Qingerlian produced water in Changqing Oilfield

为了提高庆二联采油污水回注效率,并确保其达标回注,针对其含油量、悬浮物、硫化物、细菌含量高的特点,应用化学氧化/絮凝处理方法,通过对pH值、除硫剂种类及加药量、无机絮凝剂和有机絮凝剂种类、加药量及加药时间间隔的优选,对采出水进行了回注处理研究.结果表明:当pH值为7.5、除硫剂质量浓度为60mg/L、无机絮凝剂质量浓度为100mg/L、有机絮凝剂质量浓度为1.5mg/L、加药时间间隔为30s时,处理后水悬浮物质量浓度和含油质量浓度分别为1.98mg/L和4.65mg/L,平均腐蚀速率和细菌含量分别为0.0128mm/a和101个/mL,达到油田回注水的水质标准.

Qingerlian oilfield produced water has high contents of oil,suspended substance,bacteria and sulfide.In order to make the produced water used for reinjection,the produced water is treated by chemical oxidation/flocculation.The effects of pH value,the category and the dosage of desulphurizing reagent and the category,the dosage and the adding interval of inorganic flocculant and organic flocculant on the treatment result are studied.The results show that,the mass concentrations of the suspended solid and the oil in the treated water can reach to 1.98 mg/L and 4.65 mg/L respectively,and the average corrosion rate and the bacteria content of the treated water can reach to 0.012 8 mm/a and 10 /mL respectively when the pH is 7.5,the dosage of desulphurizing reagent is 60 mg/L,the mass concentration of inorganic flocculant and organic flocculant is 100 mg/L and 1.5 mg/L respectively,and the interval of adding the reagents is 30 s.The quality of the treated water meets the needs of re-injection water.