| With the development of economic construction in Tianjin, especially the opening and development of Binhai New Area (TBNA), the landfill of the increasing waste in the city has been doing great harm to the eco-geological environment. In order to provide the waste disposition policy and the ecological environmental protection with scientific proves, a research has been carried out systematically on the migration laws of waste pollutants in soil and on the purification of soil and microorganisms, with the specific eco-geologic environmental condition of Tianjin being considered. The main results are as follows:The retardation coefficient of different soil types to different pollutants has been measured by means of Soil Colum test and Batch test and the migration model of the waste pollutants in the soil has been established. Accordingly the general features of the migration are revealed: as to the migration of different waste pollutants in the soil, the migration of COD goes the most easily while that of TP the most difficultly; as to the retardation abilities of different soil types to the waste pollutants, silt clay outperforms silt soil and medium sand distinctively, silt soil> silt sand> medium sand in general.The overall characteristics of the purification rate of the soil to the waste pollutants are revealed through Soil Colum Test: as to the different soil types, silt soil ranks the top in the removal ability while medium sand the bottom; as to the different waste pollutants, the soil removes TP best and COD the worst. The purification mechanism of the soil to the waste pollutants has been studied: the removal of COD relies mainly on adsorption while taking biodegradation as subsidiary; the removal of TN、NH3-N is the combination of adsorption, nitrification and de-nitrification. The removal capability for TP relies mainly on precipitation reaction while taking adsorption as subsidiary.The serial indoor simulation test of purification and repair of the waste pollutants by microorganism shows that microorganism not only removes nitride and the organic, but also purifies certain toxic metals. Natural microorganism groups present low efficiency and bad effect of purification and repair on the waste pollutants. Microorganism with artificial strains can improve the purification and the better purification effect can be achieved with both strains and nutrients. |
