Study On Removal And Regulation Techniques Of Typical PPCPs In Water Treatment System

In resent years, some micro-pollutants, such as Pharmaceuticals and Personal Care Products(PPCPs), in water environment have been detected frequently. Such kind of pollutants comes from people's daily lives and industrial emissions. It will cause direct and indirect influence for environment, Biological and human health, because of wide biological activities and low degradation rate characteristic. So, this issue has caused widespread concern in the international community.Sulfadiazine and Carbamazepine are widely existed and largely used as typically pharmaceuticals in aquatic environment. Information about physicochemical characteristics has been observed. Nevertheless, the microscopic researches on the kinetics, mechanisms and detailed reaction pathways of these processes are relatively few. So it is a matter of great significance to find the degradation technologies, some testing techniques and mechanisms in those contaminations.Thanks to the low concentration of PPCPs in source water, SPE-HPLC is employed as the basic analytical methods to determine the removal and change regularity of Sulfadiazine(SD) and Carbamazepine(CBZ). The convenient treatment method is pre-oxidation, coagulation and filtration. Three kind of treatment methods, Ozone-actived carbon adsorption, catalytic ozone-actived carbon adsorption and loaded ZnOOH catalyst are utilized in advanced treatment. Both the convenient and advanced treatment process are employed in simplified manpower model for both SMZ and NOR in confected water and the target compound in source water which analyze its fate in water treatment system, and synergistic removal with other micropolutants as well as the main control conditions.The experiment results showed that:the common technologies used in water treatment plants may not be efficient enough to accomplish their complete removal. The optimal removal conditions were described after operation on the simulation system. For the pre-oxidation, the orthogonal test was carried out to be optimize degrade conditions, considering the affection of oxidation time and oxidant dosage. The conditions have less affection on the removal of SD or CBZ. The optimal conditions were that:for SD, oxidation time was 60 min, KMnO4 dosage was 0.5mg/L; for CBZ, oxidation time was 90 min, KMnO4 dosage was 1mg/L. In coagulation part, polyaluminium chloride(PAC) and polyacrylamide(PAM) have been used as coagulant and flocculant. The flocculant dosage has been a great impact on the removal result. Excess dosage may lead to water quality deterioration. The dosages of coagulant and flocculant are 7 mg/L PAC,0.25 mg/L PAM for SD;8 mg/L PAC,0.25 mg/L PAM for CBZ, respectively. The removal in sand filtration is lowest, in the condition of column height 540mm, water inflow 5.31m/h, SD removal was 8%, and CBZ removal was 14%. In source water, the removal of SB and CBZ were 25.7% and 34.5% under common technologies treatment. In advanced treatment, the method of ZnOOH catalyzed ozonation can obviously improve the removal effect compared to single ozonation process. Removal efficiency has increased by 30% to 40% under the same conditions. However, this method has the disadvantage of losing ZnOOH catalysts and second pollution. In order to resolve this problem, ZnOOH is loaded on the surface of active carbon. The experimental results of source water and wastewater are simple. In active carbon absorption experiment, the breakthrough time of absorption-catalytic oxidation process is later than absorption-oxidation process. Absorption system with continuous influent of 60 days showed that the contents of SB and CBZ in effluent were under the detection limit. In source water experiment, SB and CBZ removal in effluent were over 10%, respectively. The total removal rate is up to 95%.By GC-MS detecting, the chemical bonds in SD and CBZ molecules are broking under the optimal degradation conditions. Degradation product of SB in water treatment system is sulfanilamide styrene and C10H9N3, therefore, the degradation product of CBZ is diphenyl acetonitrile and some low molecular materials.