Optimization of Filtration-Backwashing Operation Pattern for Polymer-containing Wastewater Based on the Interlayer Graded Filter Material
With the of widespread application of polymer flooding tertiary oil recovery technology,polymer-containing-wastewater has become a difficult problem in the treatment of oilfield produced water.It was deemed to be an effective mean to improve the treatment effect of polymer-containing wastewater by double-layer or multi-layer filter material and the change of filling height ratio for interlayer graded filter material.Based on the actual operation of the sewage treatment stations with quartz sand and magnetite as the main filter materials,starting from the relationship between the different filling height ratios of interlayer graded filter material,the filtration-backwashing process of polymer-containing wastewater was studied by numerical simulation,and the effect of interlayer graded filter material on the performance of filtration-backwashing was revealed.Combined with experimental verification,the operation pattern of filtration and backwashing of polymer-containing wastewater was optimized.The results showed that the significant fluctuation characteristics of pressure field in the filtration process of polymer-containing wastewater were concentrated in the filter material layers region.With the decrease of the filling height ratio,the significant fluctuation of pressure field turned from the upper part of the filtering layers to the deep part of the filtering layers.Meanwhile,properly increasing the thickness of magnetite filtering layer was beneficial to remove suspended particles in the filtering layers.During backwashing,when the thickness of quartz sand filtering layers increased,the movement characteristics of filter material layer particles was obvious,which was beneficial to the desorption of suspended particles attached to the surface of filter material particles.It was recommended to filter the low polymer concentration wastewater by the interlayer graded filter materials with filling height ratio in the range of 1.67～2.20,and filter the high polymer concentration wastewater by the interlayer graded filter materials with filling height ratio in the range of 1.28～1.67.The results provide a basis for the design and implementation of interlayer gradation adjustment scheme in the improvement of filtration treatment of polymer-containing wastewater,and the selection of filter material and the optimization and design of multi-layer gradation scheme.
国家科技期刊平台
NSTL
万方数据
