This study was to suggest the appropriate use of water disinfection equipment by using calcium hypochlorous acid [Ca(OCl)2] as a disinfectant. The experimental disinfection equipment consists of polypropylene filter and acrylic housing. The housing has six holes to adjust disinfective solution’s volume. The disinfection equipment was installed in water tank(1 ton). The principle of disinfection equipment is that disinfective solution dissolved in PP filter was spilled outside through housing’s hole and diffused in water tank. In case of steady state (closed system), optical disinfectant dose was 20 g in Water tank(1 ton). In case of unsteady state (water supply and outflow condition were applied), optical disinfectant dose was 40 g in water tank(1 ton). The experimental disinfection equipment is proved to be able to control the residual chlorine concentration in water tank by adjusting disinfectant’dose.
