GC-MS/MS Detection And Formation Potentials Of V-DBPs In The Effluents Of WWTPs

There are pathogenic microorganism in the effluents of WWTPs. If dischargedditectly, the effluents would not only endanger the environmentbut also theaten the saftyof the drinking water downstreams, so they must be disfected before discharged.Butthere are kinds of organic matters with high concentrations,so they can produceabundant disinfection by-products(DBPs) in disinfection process. Researches show that:DBPs are not only harmful to the health of mankind, but also harmful to aquaticorganism.So it’s very important to deveop a new determination method and to study thereduction of the formation potential.The object of this paper is to develop a detection method for thirteen kinds of voiatiledisinfection by-products(V-DBPs) and their formation potentials in wastewatereffluents:(1)The detection method for13kinds of V-DBPs has been developed based onliquid-liquid extraction(LLE) followed by gas chromatography-triple quadrupole massspectrometry (GC-MS/MS). This study has confirmed the GC qualitative ion andquantitative ion of the13kinds of V-DBPs for the first time and optimized the separationconditions. Compared with previous methods, this method greatly improves thesensitivity (LOQ for ng/L) and can determine all the13kinds of V-DBPs accurately. Ithas these advantages: short-time determination, well separation and cleanchromatogram. The method was validated by the analysis of surface water, tapwater,groundwaterand wastewater effluents samples spiked with2.5and25 μg/Lindividual V-DBPs, with the relative analyte recoveries being in theranges of4.7–115.9%,84.6–119.1%87.1–120.6%and81.6–126.1%for the four kinds of watersamples respectively, indicating that this method has good accuracy.（2）Aluminumsulfatewas used as coagulant and the effluents of WWTPs as raw water.Experiments have been carried out, which are on the remove of the V-DBPs precursorsand its formation potential affected by the dosage of coagulants and different pH duringthe coagulation process. The results show:(a) When pH=6,the dissolved organic matters(DOM)have been gradually reduced until the balance with the increase of the dosage ofcoagulant.When the dosage is45mg/L,the DOM has been reduced to an ideal level andthe removal of the V-DBPs formation potential is also satisfying.(b) When the dosage isconstant (Al2(SO4)3=90mg/L), differen pH has great effects on the coagulation, theDOM has been decreased first and then increased, when pH=9, DOM after coagulationis almost the same as that in raw water. The V-DBPs formation potential presented asimilar tendency; when pH=6,the coagulation shows the best results, DOC and UV254have been removed largestly and the removal of the V-DBPs formation potential is alsothe best.