The Study Of Transport And Transformation Of The Pollutants In Aeration Zone Of Cihe River

Base on determining the contents of pollutants in variously depths in aeration zone, we confirmed the kinds and distributing of pollutants in Cihe River. The results showed that Cr ( VI) and organic compounds could be adsorbed and degraded completely, and the contents of SO42' and Cl- were lower, but the concentration of NH4-N was higher than standard, so it may be enter and pollute the groundwater.We researched the transport and transformation of COD in aeration zone by the simulative experiment in laboratory. The study included static adsorption, static degradation and dynamic soil column experiments. Longitudinal dispersion coefficient ( D ) , adsorption coefficient ( Kd) and biodegradation coefficient ( Ki) were obtained trough curve fitting and parameter estimation. The results indicate that the transport and transformation of COD in aeration zone were due to dispersion, adsorption and biodegradation, so a mathematical model that simulated these processes was developed. In the model, the adsorption is represented by Henry's law: S=KdC, which adsorption coefficient ( Kd) was 0.0693, the biodegradation by a first order kinetics : c=coe-klt, which biodegradation coefficient ( Ki) was 0.0499d-1, and Longitudinal dispersion coefficient ( D ) was 0.00242 m2/d in this experiment .Model results match successfully with experimental data. Modelsimulations are performed in the study. It is noteworthy that the mathematical model will be useful in quantitatively predicting the contents of COD in aeration zone of Cihe River.