| Groundwater recharge with reclaimed water is a world-wide attempt, the experience shows that: the reclaimed water recharge to groundwater aquifer is an effective way to increase the storage capacity of groundwater resources, and can be a better use of aquifer storage space, and play a regulation function of a year and between inter- annual. However, because of the limited of economic and technical, salt difficult to be effectively removed from the reclaimed water. it will affect the water supply security, must be given due consideration, therefore, it must be given due consideration.According to engineering geologic investigation and soil sample test analysis, selects reclaimed water of Chao-bai River in Beijing Shun-yi to take three kind of typical representative soil medium (sandy gravel, fine sand, silty clay) as the object of study, and uses the reclaimed water of Chao-bai river to carry on the leaching simulation test.The actual river-water leaching single-medium simulation column test results shows that, the cation exchange adsorption mainly manifests is between the K-Ca exchange, and in the silty clay column, the cation exchange function compares the sandy gravel column and the fine sand column is more remarkable. Moreover, the column test result also indicated that, along with clay content and total organic compounds (TOC) increase, with cation exchange capacity (CEC) and total amount of clay minerals rise, in the typical medium leaching simulation column experiment, the cation exchange function's equilibrium time is also longer, respectively is 72 days for the sandy gravel,80 days for the fine sand and 86 days for the silty clay. The quantificational result computation has also proven the above conclusion, the background value of various anions and cations concentration of the silty clay medium is highest, and the contribution quantity of the total hardness of the unit mass silty clay medium and the total dissolved solids (TDS) is biggest, respectively is 57.67mg·100g-1 and 69.52 mg·100g-1.The actual river-water leaching combination-medium simulation column test results shows that, in the combination-medium simulation column, the cation exchange adsorption also mainly manifests is between the K-Ca exchange, and in the layer of sandy gravel of the combination-medium column, the direction of cation exchange mainly is calcium ion in the water exchange to the potassium ion in the soil-medium, but in the layer of fine sand and silty clay of the combination-medium column, the direction of cation exchange mainly is potassium ion in the water exchange to the calcium ion in the soil-medium. Second, total hardness and TDS of effluent water quality are the general trend of lower in the combination-medium column, respectively decreased by 4.69mg/L and 17.64mg/L, this phenomenon is speculated the reason is that the lower temperature of test ambient,the changes of enter water chemistry type (from water chemistry type of HCO3-Na change ioto water chemistry type of HCO3-Na,Ca) and the function of cation exchange of its own in leaching simulation column test is in a critical state and so on. Moreover, the contribution rate of the transition layers of the actual river-water leaching combination-medium column for the total hardness and the total dissolved solids (TDS) is bigger than the contribution rate of the layers of the single-medium.
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