The direct reaction of ozone with chlorine accounts for a significant amount of the chlorine and ozone demand found when the two oxidants are used in combination under water works conditions.doi:10.1016/0043-1354(83)90270-1Werner R. Haag
In bench-scale tests with short free-chlorine contact times (<1 h) and post-chloramination (24 and 72 h), trihalomethane (THM) formation resulted from a combination of pre-chlorination and post-chloramination. THM formation at 25 or 10掳C in the presence of chloramines was 16 or 35 ...