银川地区饱和细砂含水介质弥散实验研究

以水动力弥散理论为基础,在中国石油宁夏石化分公司炼油厂和废渣场各采取5组潜水含水层细砂岩心样,采用NaCl做示踪剂,进行室内一维沙柱弥散实验,以半无限含水层中污染物迁移模型的解析解计算了弥散度,并探讨了室内一维沙柱实验测定含水层弥散参数的误差来源,为地下水水质模型的建立提供基础。研究表明:炼油厂潜水含水层弥散度与废渣场潜水含水层弥散度基本接近。模型误差是对室内一维沙柱实验确定弥散参数产生影响最大的一类误差。目前,需加强银川平原大尺度含水层弥散特征的研究。

Experiment on the mass dispersion in porous media of saturated fine sand in Yinchuan area

Based on the hydrodynamic dispersion theory,one-dimensional sand column diffusion experiments were carried out in laboratory.The core samples of phreatic aquifer media were collected in the refinery site and waste dumps site of Ningxia petrochemical branch company of China petroleum with five samples in each site.The NaCl solution was used as a tracer in the experiments and the analytical solution to the contaminant transport model of half infinite aquifer was used in the calculation of the dispersion parameters in porous media of saturated fine sand.The source of errors in the determination of diffusion parameters was also discussed.The study results have shown that the dispersivity determined by the experiments is close to each other in the waste dumps site and the refinery site.The model error imposes the most influence on the accuracy of dispersion parameter.Furthermore,field dispersion tests in large scale should be required to fully understand the dispersion characteristics of aquifer media in the Yinchuan Plain.