Study On The Removal Effect Of Organophosphate Ester By Conventional Drinking Water Treatment Process

In this paper,the removal efficiency on organophosphate esters（OPEs）by conventional water purification process was studied.The traditional water purification process was widely used to carry out the pilot optimization test.Six OPEs:TEP,TEHP,TPhP,EHDPP,TCEP and TCPP were taken as the target substances to explore the removal efficiency on OPEs by the traditional water purification process.Besides,the operating conditions selected in the actual production were optimized.At the same time,the two new water purification processes of multi-media-activated carbon filter and ultrafiltration were sampled and monitored for several days to explore the removal efficiency by the new water purification process on OPEs.In the next,we compare the removal efficiency by new water purification process on OPEs with that of the traditional water purification process.The following conclusions are drawn:（1）Pilot test results show that prechlorination,coagulation clarifying,filter filtration and disinfection can remove 27.84%,31.90%,26.63%and 9.95%of the six target OPEs in water.Respectively,it shows obvious removal effect on alkyl and aryl organophosphate esters,but there is a not obvious removal effect on chlorinated organophosphate esters.（2）The optimization results of the whole purification process（prechlorination-coagulation clarification-filtration）showed that 62.13%OPEs in the water could be removed under the operating conditions of 1.5 mg/L NaClO,20 mg/L FeCl₃ and15 mg/L PAC.Under the above condition that saving time and cost,the conventional water purification process can achieve similar removal rate with the biological filter and pre-ozone water purification process reported in the literature.（3）The ultrafiltration process with multimedium-activated carbon filter can remove 25.75%OPEs in water on average.The ultrafiltration has a good removal effect on OPEs,especially on chlorinated organophosphates.In this paper,the removal effect on OPEs by the new water purification process is lower than that by the traditional water purification process.To sum up,it cannot completely replace the traditional water purification process,but they can assist the traditional process in production as an in-depth treatment link.By studying the removal effects of traditional and new conventional water purification processes on OPEs,this paper recommended optimized operating conditions for water purification plants,defined the removal rules of different monomer OPEs substances in the process of water purification,filled the current research gap of new water purification processes,and provided a basis for the scientific operation and selection of water purification processes.