Research On UV Radiation To Accelerate The Biodegradation And Mineralization Of Quinoline

Quinoline is discharged largely into the environmental systemsevery year. When quinoline is degraded by biological method, thegrowth of the microorganism will be inhibited,and the degadtionefficiency will be effected. Inorder to relieve the inhibition of quinolineto the microorganism,the reasearch used photolysis and photocatalysisto make a pretreatment to quinoline, and designed a airlift-internalloop photolytic biological coupling reactor（ILPBR for short）. The reactorcould combine the ultraviolet radiation degradation and biologicaldegradation effectively, and try to degrade quinoline efficiently.In order to research the remission effect of the photolysis andphotocatalysis on quinoline to the inhibition of microorganism, theexperiment uesd shake bottle as a biological response, and ILPBR as areactor for pretreatment. The experiment respectively used threemethods which are biological degradation only （B1）, photolysiscoupling biological degradation（P/B1） and photocatalysis（P/TiO₂/B1）to make intermittent degradation experiment on quinoline withdifferent concentration inorder to understand the degradation ofquinoline, mineralization extent and the growth station of themicroorganism. Then the research utilize kinetic model to describerelationship of the specific growth rate of the microorganism and theinitial COD concentration of quinoline. The results showed as follows:（1） With the help of P/B1and P/TiO₂/B1,the inhibition of quinoline tomicroorganism could be obviously relived, the degradation rate andmineralization extent of quinoline could be improved futher.|If the arrangment was showed sortrows, the result was B1<P/B1<P/TiO₂/B1.（2） Caculated with Aiba equation, by analyzing the kineticparameter, it was found that with the pretreatment of ultravioletphotolysis and photocatalysis, the inhibiution constant reduced about23.9%and26.1%respectively. Meantime, the maximum degradationrate increased largely. This suggested that pretreatment couldeffectively relive the inhibition of quinoline on the microorganism onone hand, on the other hand,it could enhance the growth rate of themicroorganism.In the research of ultraviolet radiation coupling biomembrane todegade quinoline, the experiment respectively used three methodswhich are photolysis degradation only （P）, biomembrane degradationonly （B） and photolysis coupling biomembrane （P&B） to makeintermittent and continuous degradation experiment on quinoline withdifferent concentration inorder to understand the degradation ofquinoline, mineralization extent. Then the research utilized kinetic modelto describe relationship of the initial degrdation rate and the initialconcentration of quinoline when the react time was10minutes, andanalyzed the changment of the microorganism.on the biomembranewhen exposured to the ultraviolet. Besides, the research used P&Bmethod to make intermittent degradation experiment on the200mg/Lquinoline liquid.Compared with the synchronization couplingexperiment, the paper discussed the influence of ultraviolet radiationtime to quinoline.The results showed as follows:（1） By means of the ILPBR integrated reactor, the microorganismcan maintain a superior activity when exposured to the ultraviolet. Thereactor combined the ultraviolet radiation with the biomembranemethord effectively so that it could relieve the inhibition of the organicmatters to the biomembrane,enhance the degradation efficency tothe organic matters. （2）The intermittent and continuous degradation csuggested thatP&B method is of effect to the degradation of quinoline. Besides, thevolume removing load of quinoline was obviously better than P methodand B method, and the mineralization extent of quinoline wasincreased.（3） Haldane model could be used to discribe the biomembranedegradation, ultraviolet photolysis coupling biomembrane degradationof quinoline. When ultraviolet photolysis and biomembranedegradation are coupled, the inhibition constant reducd about36%,the maximum degradation rate increased almost double.In this way,the degradation rate of quinoline could be increased.（4）According to the analization of molecular biology andcombined with the degradation rate experiment, the constitute of thebiomembrane flora which grew in the acetalized fibre were changedueder the ultraviolet enviroment,but the survived microorganism stillremained degrading activity to quinoline.In conclusion, the inhibition of quinoline to the microorganism wasrelived by means of photolysis and photocatalysis degradation. TheILPBR integrated reactor was developed which could cmobinephotolysis and biological degradation to treat quinoline wastewaterwas of borad prospects for development,and could make greatsignificance for future research.