调查了25家具有代表性的水处理厂，以进行比较 原水和污水的微生物、物理和化学水质差异 废过滤器反冲洗水（SFBWs）。根据观察到的贾第虫和 隐孢子虫水平，确定回收率为5-10% 足以将原生动物对周围原水的影响降至最低。使用 细胞培养聚合酶链反应法，感染性隐孢子虫卵囊 在原水和SFBW样品中观察到。粒子的存在 SFBW样品使高锰酸钾需求量增加了5.5倍，并且 二氧化氯的需求量增加了4.0倍。然而 SFBWs中的颗粒不影响隐孢子虫的灭活。 用聚合物对SFBW进行常规处理，可以很好地去除废水 浊度、颗粒物和微生物。可使用可反洗深度过滤器 代替传统的过滤器，用于在实验室控制隐孢子虫 SFBW。包括29个参考文献、表格和图表。

Twenty-five representative water treatment plants were surveyed to compare differences in microbial, physical, and chemical water quality of raw waters and spent filter backwash waters (SFBWs). On the basis of the observed Giardia and Cryptosporidium levels, it was determined that a recycle ratio of 5-10% would be sufficient to minimize the impact of protozoa on ambient raw water. Using the cell culture-polymerase chain reaction method, infectious Cryptosporidium oocysts were observed in raw water and SFBW samples. The presence of particles in the SFBW samples increased the potassium permanganate demand by a factor of 5.5 and the chlorine dioxide demand by a factor of 4.0. However, the presence of particles in SFBWs did not affect the inactivation of Cryptosporidium. Conventional treatment of SFBW with polymers resulted in excellent removal of turbidity, particles, and microorganisms. A backwashable depth filter can be used in place of a conventional filter for control of Cryptosporidium in clarified SFBW. Includes 29 references, tables, figures.