入渗率对Sr在沙土中迁移的影响

摘要

通过柱法实验对不同入渗率下Sr2+在沙土中的迁移行为进行模拟研究,采用惰性示踪剂Br示踪水流状况,测定不同入渗率下Sr在沙土柱流出液中的浓度曲线,并采用CXTFIT程序计算土柱中Sr的运移随时间的变化趋势.结果表明,数值模拟计算结果与柱实验结果一致,CXTFIT程序可较好模拟核素在土柱中的运移特性；随入渗率的增大,核素迁移速度和弥散系数增大,阻滞系数和有效孔隙度不变.%Migration behavior of Sr2+ was studied in sandy columns with a pluse injection and Br as an tracer for water flow under different conditions of infiltration capacity.The migration trend of Sr2+ with time in soil column was calculated by CXTFIT program.It is show that the same result for Sr2+,Br concentration in effluence as function of time is obtained by column experiments and CXTFIT program,which indicate that the migration characteristics of radionuclide in soil column can be well simulated by CXTFIT program.Migration velocity of nuclides and dispersion coefficient is increasing,the retardation factor of soils for Sr and effective porosity is constant,while infiltration capacity is increasing.