Inactivation of Chironomid larvae from drinking water by ozone and its removal using ozone-GAC process
Bench scale experiments were conducted on the inactivation of young Chironomid larvae by ozone,chlorine dioxide and liquid chlorine.Major influence factors on the inactivation effect of ozone were studied.Based on the bench scale experiment results the feasibility of young Chironomid larvae removal by the ozone-granular activated carbon(GAC) process was discussed.It was found that ozone showed better inactivation effect than other two oxidants.Complete inactivation could be reached under the condition of 1.0 mg·L~(-1) of ozone with 25 min exposure.The increase in water depth of the reactor was helpful to increasing inactivation rate.COD_(Mn) greatly influenced inactivation rate in neutral water body.1.0 mg·L~(-1) of ozone with 11 min exposure caused complete inactivation of young Chironomid larvae in filtrated water in the dynamic experiment.0.8 mg·L~(-1) of ozone combined with GAC treatment was able to entirely eliminate Chironomid larvae with low activity.