铜银负载沸石基质雨水滞留池的除菌性能

To control pathogenic microorganisms pollution in urban water, a rainwater retention tank with filter media of copper or silver loaded zeolite was designed to remove pathogenic microorganisms with coliform bacteria as indicator bacteria in combined sewer overflow. The metal loss and bacteria-eliminating abilities of copper loaded and silver loaded zeolite were investigated by batch experiments, and the latter was further proved by filled simulated columns test for treating synthetic water with different coliform bacteria concentrations or combined sewer overflow. The results show that Cu²⁺ loss from copper loaded zeolite was lower than Ag⁺ loss from silver loaded zeolite. The bacterial removal efficiencies of the two zeolite columns were above 90% at the influent E. coli. concentration of 10⁵~10⁷ CFU•L^-1. During 18 d consecutive filtration operation, the bacterial removal efficiencies of the two zeolite columns maintained above 90% for the combined sewer overflow withE. coli. of 10⁶ CFU•L^-1, which was not affected by COD, TN and TP. In short, the retention tank with filter media of copper or silver loaded zeolites can effectively reduce the risk of pathogenic bacteria in rainwater runoff.