Abstract:

The produced water from ASP (alkali, surfactant and polymer) flooding oil had higher viscosity because of the presence of polymer residues, which made the separation of oil and water even harder. In this paper the degradation of polymer by using ultrasonic enhanced O₃ oxidation was performed in (20+28+40) kHz three orthogonal field with the intensity of 1.6 W·m^-2 and the addition of 7.5 mg·L^-1 O₃ for 15min. The change ratio of dynamic viscosity could attain 86.1%. By calculating utilization rate of O₃ and detecting the intermediate products of H₂O₂, it showed that the ultrasonic enhanced O₃ oxidation introduced the synergistic effect, increased the transfer efficiency and promoted the generation of ·OH. The polymer degradation efficiency was increased three times and the reaction time was shorted about 3/4.

Key words: polyacylamide, ozonation, ultrasonic enhancement, synergistic effect

摘要：

三元复合驱采油开发中注入的聚丙烯酰胺等化学物质随采出液一并采出, 导致采出液黏度增加, 受此影响, 污水处理系统沉降过滤装置处理效率下降, 出水水质难以稳定达标回注。降低黏度关键在于降解污水中聚丙烯酰胺, 本研究采用O₃氧化降解聚丙烯酰胺, 降解过程中引入超声, 利用超声强化作用提高O₃降解效率。结果表明, 在三频正交场(20 kHz +28 kHz +40 kHz)作用下, 控制声强1.6 W·cm^-2, 作用时间15 min, 进水聚丙烯酰胺平均含量300 mg·L^-1, 黏度4.5 mPa·s, 降解聚丙烯酰胺后水体黏度降低到0.7 mPa·s, 黏度变化率达到86.1%。通过检测反应前后水中和大气中O₃浓度, 表明超声强化作用将O₃利用率提高55%。O₃降解过程引入超声产生协同效应, 增加了O₃传质效率, 促进 O₃转化为H₂O₂, 进而生成高活性·OH, 促使聚丙烯酰胺降解效率提高3倍, 反应时间约缩短3/4。

关键词: 聚丙烯酰胺, 臭氧, 超声强化, 协同效应