Abstract: A pilot study was conducted to optimize the operation of different combinations of chemical agents using the Luan River raw water. By analyzing the treatment effects under different pre-oxidation and chemical combination dosages,the optimization parameters of chemical agents for Luan River raw water in different water quality periods were proposed. The results show that during the low-temperature and low turbidity phase of the pilot test,a dosage of 20 mg/L PAC and 15 mg/L FeCl₃ without pre-treatment,and a dosage of 0.8 mg/L preozonation,10 mg/L PAC and 10 mg/L FeCl₃ can both meet the effluent quality requirements. During the normal temperature and turbidity period,a dosage of 0.5 mg/L prechlorination,15 mg/L PAC and 15 mg/L FeCl₃ can meet the effluent quality requirements,and during the high temperature and high algae period,a dosage of 1.2 mg/L prechlorination,20 mg/L PAC and 15 mg/L FeCl₃ can meet the effluent quality requirements.

Key words: preoxidation of raw water, iron aluminum compound addition, pilot study, optimization operation