关键词: 下向流过滤器, 砂滤, 集水单元, 结垢沉积, 采出污水

Abstract: The influences of filtration rate and polymer concentration in produced water on the scaling deposition behavior were studied by building the simulation experiment device,considering the characteristics of downward flow filter water collection process and the problems existing in production. Based on the material and internal structure in the water collection tube,a experimental unit model was established,in order to investigate the effect of structure of water collection tube on scaling deposition. In addition,the internal mechanism for the scaling deposition in the water collection tube was discussed.The results indicate that FeS,Fe2O3,CaCO3,and aluminosilicate are the main constituents of scaling depositions in the water collection tube.The high intensitive aggregation and adhesion between the scaling deposition and the inner wall of the water⁃collecting tube are proved to be influenced by temperature, filtration rate and water quality.The water temperature environment of the surface system provides a suitable propagating environment of the sulfate⁃reducing bacteria (SRB), which is used to accelerate the corrosion beneath the scale in the water collection tube. The filtration rate shows two mechanisms of "scaling" and "stripping".The polymer in waste water would induce a synergy effect between "co⁃deposition" and "chelate solubilization". Besides of that,the galvanic corrosion by the structure of the water collection tube is proved to be the internal mechanism for accelerating the scaling deposition.

Key words: Downward flow filter, Sand filtration, Water collecting tube, Scaling deposition, Produced water