Evolution Of Disinfection By-products In Drinking Water In Different Treatment Technology

With the increasing industrialization of our country. Variations of the natural water in China have been increased greatly due to the heavy pollution in recent years and the complexity of the natural water itself. The nature water is main source of drinking water. Therefore, the processes to kill the bacteria in the water and reducing the potential carcinogenicity disinfection by-products (DBPs) generated during the disinfection process are becoming an important problem.The purpose of disinfection is to kill the bacteria in the water, but disinfection can generate disinfection by-products. Currently, we have known the carcinogenicity potential of disinfection by-products to people. And two main courses of disinfection by-products are haloacetic acids and halomethane. Our country do not have a set of analytical method which is used for the detection of nine haloacetic acids. So, it is necessary to bulid a set of method which is used for the detection of Haloacetic acids in order to provide reference for our country. In this experiment, we use liquid-liquid extraction following derivatization to detect the haloacetic acids. We researched the key step which affected the recovery and lowest detectable limit. Finally, we optimized a set of method which can be used for the detection of samples. By optimization, we simplified the addition of CuSO4, induced the addiontion of Na2SO4.And we avoided the harm to people by replacing diazomethane by acidified methylalcohol. Meanwhile, we shorted the heating up time of chromatographic column. The results show that the MDL of MCAA, DBAA, TCAA are 0.04μg·l-1,0.02μg·l-1,0.2μg·l-1. The recovery rate of them between 88%and 109%. It can satisfy the requirement of USEPA and China's drinking water standards.This experiment focus on the water treatment technology of representative city of North and South.Researching the evolution of HAAs and THMs and analyze the reason for their varying. The results show that the THMs are the major disinfection by-products in water before disinfection. But the HAAs became the major disinfection by-product after disinfection. Thus, the HAAs potential are the major DBPsFp.But by contrasting the disposition of disinfection in two cities, we found that the THMs and HAAs of the South representative city are generally higher than the North representitative city. Meanwhile, the bromoDBPs of South city are generally higher than the North city. Meanwhile, The oxygen-active carbon-chloration of No.l water treatment process in North has the lowest THMs. The active carbon-chloration-ammonification of No.2 water treatment process in North has the lowest HAAs. The rechloration of No.l water treatment process in South has the lowest THMs. The rechlorination-ammonification of No.3 water treatment process in South has the lowest HAAs.The amount of DBPsFp in the water is the main reason immediate impact the generation of DBPs in water. So we researched the amount of DBPsFp of the North representative city and the South representative city.Meanwhile, we researched the evolution of DBPsFp in different type of water treatment technology in two representative cities. And analyzing the removal rate of DBPsFp in different water treatment technology. The results show that the DBPsFp of South representative city are generally higher than the South representative city.And the active carbon and O3 active carbon have the highest removal rate to disinfection by-products.