| Recently,all kinds of organic compounds,heavy metal and radioactive waste have been put into environment due to rapid development of petroleum chemical industry, irrational bury of industry and agriculture waste,accident discharge of pollutant and equipment leakage of oil store.This gives rise to heavy pollution for both surface water and underground water as well as soil.Because of hidden characteristic and irreversibility,the pollution of underground waste is difficult to reduce and control.So eliminating organic compand.pollutant of underground water has become an imperative task of environmental protection.This paper mainly studied the law of transformation and transplantation of nitrobenzene in groundwater which based on actuality of serious pollution which need study imminently in theory and control technology.And also study the prevention and control technology of the pollution of nitrobenzene-permeable reactive barrier technology.In the paper,we should firstly understand the character and hazard of nitrobenzene. Through the experiment,the tracer experiments to determine the actual velocity of underground water in tank,for provide the parameters of the migration experiment,in accordance with the results of tracer experiments as well as the aquifer media parameter indicators were identified tank seepage of groundwater flow,Darcy flow and permeability of sand.Then we study the law of transformation and transplantation of nitrobenzene in groundwater In order to explore the theory of remediation of nitrobenzene pollution in groundwater.And the leaching experiments were carried out to determine the harmfulness of filler.Finally,choose the best parameters of the fill material of permeable reactive barrier through the experiment,and determine the treatment effect of the permeable reactive barrier.The main contents of this paper are divided into the following areas:1.Tracer experimentThrough experiment,measured that the seepage discharge is 1.8mL/min,cross section area A is 30×30cm~2,the hydraulic gradient is 0.0125,calculate that the actual velocity of groundwater is 7.79cm / d,seepage velocity is 2.88 cm / d,permeability coefficient is 2.304m /d.2.The law of transformation and transplantation of nitrobenzene experiment Design seeping trough experiment.Then through these experiments,we mainly study the transport process of nitrobenzene in groundwater system.Understand the trends of nitrobenzene pollution.In order to explore the theory of remediation of nitrobenzene pollution in groundwater, we should do the experiment including seeping trough experiment.Then through these experiments,we mainly study the transport process of nitrobenzene in groundwater system.The concentration of nitrobenzene at different times horizontal direction are basically in the same trend,the concentration of nitrobenzene content can be divided into two phases,the concentration of nitrobenzene increase rapidly and nitrobenzene concentration fluctuate and stabilize phase.The first stage is the purification of sand decay phase,as a result of the purification of sand attenuate,the concentration of nitrobenzene increasing,until they reach their peak;the second stage is the purification ability of sand tend to disappear,the nitrobenzene concentration fluctuations.The concentration of nitrobenzene at different times in the vertical distribution is similarity.Water from the recent cross-section cross-section of the sample,the concentration of nitrobenzene within 26cm distance of the bottom of Percolation tank department is small. the concentration of nitrobenzene within 26cm distance of the bottom of Percolation tank department is large.This prove that from the sources of pollution entering the aquifer is not uniform distribution,and this may be due to the density of nitrobenzene(1.2kg / L) greater than water.3.Leaching experimentLet the material combined marinate in the distilled water,break out them respectively in the 15th day,the 30th day,the 60th day,to determine the sample which has marinated and the vacanted sample which has marinated in the distilled water with the way of the chromatogram shows that the matter in two samples has the same moment to appear crest,after being roasted on 800℃,all of the organic in the pitch have been carbonized,it is safe to use the combined material,the waste water which has been worked by the combined material will not produce the cycling pollution.4.Selection of he best parameters of permeable reactive barrierPermeable reactive barrier selected iron and wall carbon filler as reaction medium.In dealing with nitrobenzene waste water,the major factors include:pH value of experimental water stop time,concentration of nitrobenzene,ratio of Fe:C,particle diameter of iron fillings. The best process parameters of chemical reaction barrier is:The iron filling diameter selected is between 0.1 cm and 0.2 cm.Controlling Fe:C=5:1,When the reaction time is 40 min,the reduction rate of nitrobenzene reaches 87.5%and when the reaction time is 60 min the reaction rate can reach 94.2%.5.The consequence of Permeable reactive barrier treatment of nitrobenzeneThe conversion rate of nitrobenzene was 93.26%under the best conditions.To sum up,the experiment evidence the Permeable reactive barrier treatment of high concentration of nitrobenzene has played a considerable role,and,Chemical reactions barrier on the wall itself does not play a further pollution consequences in.groundwater.Permeable Reactive Barrier(PRB) technology has good prospects for development.It can take more effective treatment technologies to avoid the initial high capital investment,operation will take long-term energy supply,dealing with large-scale groundwater pollution and other shortcomings of the limited capacity;reaction material selection flexibility to deal with a wide range of components;building,running both in the ground,on the impact of human activities, small.PRB technology is very important in our country's social and environmental significance.
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