Physical And Chemical Properties Around Shidao Bay Nuclear Power Plant And The Effect On Distribution Coefficient Of Radionuclides

With the rapid development of nuclear technology,nuclear power plant provides power for human beings and at the same time,a large number of radioactive substances were released into the soil environment due to nuclear or radiological emergency. It is necessary to explore the key of the nuclear accident radionuclide migration regulation in the soil in order to response and restoration strategy and make assessment method for further improve the nuclear power plant on the surrounding environment. However, now researchs on the key radionuclides in soil of vertical migration patterns and environmental consequences evaluation are very few, especially aspect of soil water dynamic parameters effect on radionuclide.This thesis summary analysis the existing research results on soil water dynamic parameters and distribution coefficient of radionuclides in domestic and abroad. The study set surrounding the flourish of shidao bay nuclear power plant in Shandong province as an example and made a preliminary study about the nuclear power plant of unsaturated soil physical and chemical properties around and distribution coefficient on the periphery on the basis of experiments and analysis. The results are list as follow: 1. In view of study area around Shidao bay nuclear power plant, four direction(SW, W, NW, NNW) were selected for cross-sectional analysis soil particle composition and elevation changes of the 24 research sites. Meanwhile we compared soil bulk density, organic matter, p H, conductivity, such as physical and chemical properties among different research sites at two layers, magnetism(0- 30 cm) and deep(30-70 cm). Space mutation of physical and chemical properties were identified in the research area. Soil organic matter and conductivity of study sites decrease with the increase of soil depth. The higher altitude of study sites, the smaller the soil bulk density, organic matter and conductivity.The study area all partial neutral or acidic soil. 2. With lab measurement of soil water content and matric potential counterpart of data as the foundation,by the least squares method to construct the nom Linear equations,the empirical equation of soil water characteristic curve-van Genuchten model parameter values can determine using Matlab software. The simulation model on the aeolian sandy soil site is better than brown soil site. 3. We measured the distribution coefficient of 137 Cs,60Co and 85 Sr in the typical soil using static analysis and analyzed the influencing factors of distribution coefficient. The results shows that Kd values of 137 Cs and 60 Co are bigger,Kd value of 85 Sr is smaller in the soil profile. That means 137 Cs and 60 Co adsorption is stronger than 85 Sr adsorption in two type soil. In the brown soil,Kd value of 60 Co and are positively correlated witeh p H, electricity conductivity, silt content(P < 0.01),and Kd value of 60 Co has very significant negatively correlation with soil organic matter and sand content(P < 0.01). The distribution coefficient of 137 Cs in aeolian sandy soil was positively correlated with soil p H,sand content, negatively correlated with soil organic matter(P < 0.05).