Research On Nature Attenuation Of Nitrobenzene And Organochlorine Pesticides In Nature Waters

Organic compounds pollution is highl y attached importance to atall times. Since 20th century, more and more organic compounds enterinto environment along with the development of industry andagriculture, and the rivers are polluted badly. Because organicpollutants are complex and easily changed and the degradation is noteasily go along, organic pollutants in the water environment moredirectly threaten the health of human beings.The migration and transformation process of organic pollutantsin rivers mainly include volatilization, photo -degradation,biodegradation and interaction between organic pollutants andsediments. The migration and transformation process of organicpollutants in water environment can realized through simulationresearch. Until now, the migration and transformation models oforganic pollutants in water environment are proposed. But much ofthem are limited in some segment of the migration and transformationprogress. Simulation experiments with comprehensive consideration ofeach segment are rare. Although many model s of organic pollutants inwater environment are set, It is usual to see the report aboutapplication value of the models. For one given river and differentorganic pollutants, the application or the application extent of themodels is meaningful to know organic pollutants in the waterenvironment. The thesis focuses on nature attenuation of nitrobenzene andorganochlorine pesticides in the water environment in JiLin sect of theSonghua river. Through the research on volatilization,photo-degradation, biodegradation and the interaction betweenorganic pollutants and sediments of the two sorts of organic pollutants,we can calculate on the nature attenuation of nitrobenzene andorganochlorine pesticides by box model and find out the conclusion.The thesis choose 100m to the east side of Longtan bridge as samplingspot. This time is abundant water period.Through the result calculated by the model contrast the result whichdraft up by research on nature attenuation of nitrobenzene andorganochlorine pesticides in the savageness water environment, wecan get the result:1. On condition 1 and condition 2, in the first 6 hours, t he resultwhich calculated by the model contrast the result which draft up byresearch on nature attenuation of nitrobenzene in the wate renvironment is consistent. The concentration at 24 hour is largerthan the result which calculated by the model. Because the chosencondition is represent in the river condition, we could use the resultto deduce that the model is the same with the forec ast of the natureattenuation of nitrobenzene in water environment beforeadsorption/ desorption balance. After adsorption/ desorptionbalance, the model inaccurately reflect the process of natureattenuation of nitrobenzene in the water environment.According to the result, tend of nitrobenzene in water environment is adsorption by the sediment. Contrast to adsorption,photo-degradation is in the first place of the degradation.Volatilization and desorption are in the next place. Biodegradationlook relatively slower and it is not important contrast to others.2. On condition 3 and condition 4, in the first 6 hours, t he resultwhich calculated by the model contrast the result which draft up byresearch on nature attenuation ofα-666 in the water environment isconsistent. The concentration at 24 hour is extraordinarily largerthan the result which calculated by the model. Because the chosencondition is represent in the river condition, we could use the resultto deduce that the model is the same with the forecast of the natureattenuation ofα-666 in water environment before adsorption/desorption balance. After adsorption/ desorption balance, themodel inaccurately reflects the process of nature attenuation ofα-666 in the water environment.α-666 is extraordinarily hard todegrade consequently.According to the result, tend ofα-666 in water environment isadsorption by the sediment. Contrast to adsorption,photo-degradation is in the first place of the degradation.Volatilization and desorption are in the next place. Biodegradationlook relatively slower and it is not important contrast to others.3. On condition 3 and condition 4, no matter what hour, he resultwhich calculated by the model contrast the result which draft up byresearch on nature attenuation of pp′-DDT in the waterenvironment is not consistent. The reason is possible that pp′-DDT, DDD and DDE transform in gaited condition. It is obvious nomatter what concentration of pp′-DDT. On this condition, themodel inaccurately reflects the process of nature attenuation ofpp′-DDT in the water environment. According to the result, tend ofpp′-DDT in water environment is adsorption by the sediment.Contrast to adsorption, photo-degradation is in the first place of thedegradation. Volatilization and desorption are in the next place.Biodegradation look relatively slower and it is not importantcontrast to others. pp′-DDT is extraordinarily hard to degradeconsequently.4. Compare the three organic pollutants, the speed of volatilizationand degradation of nitrobenzene is extraordinarily larger than theothers. For the process of degradation of the three organicpollutants, photo-degradation is in the first place. The degradationofα-666 appear light dissimilation certainly, but after lightdissimilation, the speed is rapid all the same. For the wholeattenuation, adsorption is in the first place. For organochlorinepesticides, they are hard to degrade and not easy to volatilize, butthey are easy to adsorb. Tend of organochlorine pesticides isadsorption.