Study On Ozonation Technology And Simulation Of Disinfection Contactor In Drinking Water Treatment

Ozone technology has been widely used in water treatment in our country, but theresearch about it is not mature. For the better application of it, this paper study theozonation technology further. Put emphasis on the studies of pre-ozonation,O3/KMnO4 complex pre-oxidation, middling pre-oxidation, control and formation ofbromate, simulated the model of disinfection contactor.The results of study show that pre-ozonation has a good effect on the removal ofUV254,CODMn. Along with the increase of ozone dose, macromolecule organics areoxidized and decomposed, lead the increase of particles number. At the same time,because of the oxidation of ozone, unsaturated bond are destroyed, so the chromaticvalue of drinking water is decreased. In the matter of ammonia, organic nitrogen areoxidized and turn into ammonia. The relation between ozone dose and ammonia is△NH3=0.142×O3+0.012(mg/L), the limiting value of ammonia transformation is[NH3]max=0.202mg/L.This paper also study the O3/KMnO4 complex pre-oxidation. By the experimentalstudy, we find that inject KMnO4 before O3 is a good way, effect of treatment arebetter than the other ways. Algae, HAAFP and THMFP removal efficiency are 88.6%,31.9% and 17.3% respectively. At the same time, because of the decrease of ozonedose, the quantity of bromate and AOC are also decreased.Based on the O3/KMnO4 complex pre-oxidation technology, put forward a newtreatment process that is named middling pre-oxidation. From the experimental results,we find that this technology can strengthen the efficiency of sand filter, turbidity, TOCand particle number are clearly reduced.Besides the studies above, I carried out a investigation of bromate in Shenzhen,Guangdong Province, China,and analyzed the variation of bromate with position andseason. By the comparative experiments we find that multipoint injection of zone cancontrol the formation of bromate, and make the formation of bromate decrease 1/3.At the end of this paper, ozonation contactor was simulated by FLUENT. Theresults of simulation show that the designed contactor has many defects, such as deadzone, short flow and so on. On the base of simulation, this paper put forward somecorresponding measures,optimize the design of contactor for better disinfection.