Study On Removing Odorants Of 2-MIB And GSM In Drinking Water By Vacuum Ultraviolet Combined With Chlorine

The odors caused by algae can affect the sensory and potability of water,which are harmful to human health,and water supply accidents caused by these odors have occurred at home and abroad.Among these odorants,2-MIB and GSM are the most typical and widely existed,which become the studying focus of academics.The conventional water treatment techniques are poor at removing these odorants because of their stable chemical structures.In this paper,2-MIB and GSM were chosen as the study objects and vacuum ultraviolet/chlorine?VUV/Cl?technique was used as a core technique to remove 2-MIB and GSM.The analysis methods of purge and trap-gas chromatography mass spectrometry?P&T-GC/MS?were used.The main research results were as follows:?1?Single oxidation by ultraviolet or chlorine had a poor performance of removing2-MIB and GSM.When ultraviolet was combined with chlorine,the removal performances of 2-MIB and GSM were increased significantly.When vacuum ultraviolet was combined with chlorine,the removal performances were better than that of ultraviolet combined with chlorine.?2?The removal performances of 2-MIB and GSM by VUV/Cl technique were influenced by environmental factors.The reaction rates and removal performances of 2-MIB and GSM could be effectively improved when increasing the dosage of chlorine and the intensity of ultraviolet.When the reaction system was in acidic condition,the removal performances of 2-MIB and GSM were the best.The presence of bicarbonate and humic acid could inhibit the removal effects of 2-MIB and GSM.?3?In VUV/Cl/Aeration process,ozone produced by ultraviolet radiation could improve the reaction rates and removal performances of 2-MIB and GSM.The influencing characteristics of removing 2-MIB and GSM by the technique of VUV/Cl combined with aeration were similar to those by the VUV/Cl technique.?4?The removal performances of 2-MIB and GSM was inhibited significantly when tert-butyl alcohol was added into the reaction system,which indicated that hydroxyl radical plays a decisive role in the removal of 2-MIB and GSM.?5?VUV/Cl technique was superior to VUV/H₂O₂ technique by comparing the effects and costs in the removal of 2-MIB and GSM.The unit electric energy consumption of VUV/Cl technique was greatly influenced by the reaction conditions,and the purposes of energy saving and cost saving could be achieved by changing the reaction conditions.