Abstract:

With the application of polymer flooding, the viscosity of liquid and the oil-bearing capacity of water phase increases, leading to the more difficult for the separation process. As a widely accepted method, filtration is affected by process factors and its treatment effect is not stable. At the same time, ozone as a fast and efficient way for the treatment of waste water is increasingly concerned. The influences of different filter bed thickness ratio, inlet flow rate, pressure drop and pH of waste water on turbidity were studied. The results showed that the filtration was best when the ratio of walnut shell to quartz sand was 9∶13. The improvement of inlet flow rate, the increase of pressure drop and the reduction of alkalinity of waste water were beneficial to the filtration. The effects of ozone on the treatment of oil field waste water containing HPAM were investigated. The results showed that ozone can through degrading the polymer to reduce the viscosity of wastewater. In addition, the turbidity and oil content of wastewater also decreased significantly. The effective consumption of ozone for viscosity reduction was measured. It demonstrated that 5 mg of ozone could reduce the viscosity from 2.6mPa·s to less than 1mPa·s for 500mL waste water. It is suggested that combining the ozone treatment with the filtration method, using ozone for wastewater pretreatment and bonded filter material treatment to improve the filtration efficiency.

Key words: oil produced water, polymer flooding, filtration, ozone treatment, waste water treatment

摘要：

油田含聚污水随着聚合物驱的应用而黏度增加，水相含油能力强，分离难度大，对处理方式的要求越来越严格。过滤法作为常用方法，其污水处理性能受工艺因素的影响，处理效果不稳定；同时，臭氧作为快速、高效的污水处理方式日益受到关注。本文研究了不同滤料厚度比例、进水流速、滤床压降及污水pH对污水浊度等过滤参数的影响，结果表明核桃壳、石英砂厚度比为9∶13时过滤效果最优，提高进水流速、增加滤床压降和降低污水碱性有利于过滤的进行。探究了臭氧对含油含聚污水的处理效果，结果表明臭氧可通过降解聚合物以显著降低含聚污水黏度，同时污水的浊度和含油量也会显著下降。测定了臭氧降黏的有效消耗量，结果表明5mg臭氧可把500mL的含聚污水黏度从2.6mPa·s降低到1mPa·s以下。最后提出了采用臭氧对过滤污水预处理及处理过滤装置中的板结滤料、提高过滤效率的建议。

关键词: 油田污水, 聚合物驱, 过滤, 臭氧处理, 污水处理