Abstract: Granular layer filtration is widely used in the treatment system of oilfield produced water, and water distribution of granular layer filter which directly affects the purification effects of produced water plays the same significant role as the selection and arrangement of granular layer. The model of filter was built and unstructured grids were generated by Gambit. The flow rate field in the model was calculated by Fluent combined with DPM model. Based on the DPM model in Fluent software, a numerical simulation of pressure field distribution, filtration pressure drop along the axis, pathlines of particles, and particles distribution and aggregation behaviors were simulated and calculated. Then, water distribution characteristic in pressure filter of produced water was described, and optimization of water distribution process was realized. The results showed that the good performance of water distribution was obtained and the pressure drop in the filter with sieve tubes was reduced by 30.56% compared with the filter with slots. Furthermore, the filter with nine sieve tubes was optimized by its excellent water distribution characteristic. Such a numerical simulation method can provide effective support for optimization of filtration process and purification of produced water.

Key words: Water distributor, Process optimization, Pressure filter, Produced water, Numerical simulation

摘要： 粒料层过滤是油田采出水处理系统普遍采用的工艺,与其粒料层的选择和布置一样,粒料过滤器的布水均匀性特征直接影响采出水的净化处理效果。利用Gambit建立模型并生成非结构化网格,基于Fluent软件中的DPM 模型模拟计算了过滤器内部压力场分布、过滤沿程压降特征、粒子运动迹线特征及粒料层表面的粒子分布与聚集行为,进而描述了油田常用压力式过滤器的布水特征,并进行了布水工艺优化。结果表明,相比于“条缝式” 布水模式的过滤器,“筛管式”布水更为均匀,不同处理量下的过滤轴线压降平均低出30.56%,且9筛管模式布水工艺的布水均匀性特征量能取得更为优越而稳定的分布。

关键词: 布水单元, 工艺优化, 压力式过滤器, 采出水, 数值模拟