陇东油田酸化废水就地处理及经集输系统外输的可行性实验研究

Treatment of acidic wastewater in Longdong Oilfield and experimental study on feasibility of transporting treated wastewater through gathering system

对陇东油田酸化废水通过中和-沉降、中和-絮凝-沉降、H2O2氧化-中和-絮凝-沉降实验室处理效果进行对比,确定出酸化废水适宜的就地、快速处理方法和工艺条件;采用室内实验研究处理后酸化废水经集输系统外输的可行性。结果表明：在双氧水投加量0.2%（V/V）,采用NaOH-CaO复合碱调节废水pH至7.0-7.5,PAM投加量为3.0 mg/L条件下,陇东油田酸化废水经H2O2氧化-中和-絮凝-过滤处理,其各项指标均达到油田回注水的水质要求,且处理后酸化废水与集输管线中采出水具有良好的配伍性,不易结垢,并对后续原油破乳未产生不利影响。

The appropriate and rapid treating method and technological conditions of acidic wastewater in Longdong oilfield are determined by comparing the treatment effects of neutralization-sedimentation,neutralization-flocculation-sedimentation and chemical oxidation-neutralization-flocculation-sedimentation processes in laboratory. The feasibility of transporting the treated acidic wastewater through gathering system is also studied by laboratory experiments. The results show that: when the volume fraction of hydrogen peroxide is 0. 2%,the pH value of wastewater is adjusted to 7. 0 ~ 7. 5 using NaO H-CaO composite alkali,the mass concentration of PAM is 3. 0mg / L,the various indicators of the acidic wastewater treated by H2O2oxidation-neutralization-flocculation-filtration process can reach to the quality requirements of the injection water in the oilfield,the treated wastewater has good compatibility with the produced water in gathering pipelines,and it has no adverse effect on oil demulsification. The acidic wastewater can be treated in situ,and the treated acidic wastewater can be transported through gathering system.