Research on changes of hydrodynamics and ion-exchange adsorption in Brackish-Water Interface

• 作者: LIU Feng MIAO Qing-zhuang WANG Gui-ling XING Lin-xiao ZHANG Wei ZHOU Xiao-ni
• 来源期刊: 地下水科学与工程:英文版
• 学科: 工学
• 关键词: Seawater-freshwater INTERFACE WEDGE-SHAPED INTERFACE Hydraulic gradient Critical value Ion-exchange ADSORPTION
• 年，卷（期）: 2019,（2）
• 页码范围: 94-105
• 页数: 12页
• 分类号: TV

摘要

In light of multiple field experiments in typical tidal areas with active sea-land interaction, corresponding analysis through hydrodynamic simulation and of ion composition evolution all insist on following conclusions. Due to the tide, the groundwater level is basically in line with its level but with a slight lag. Moreover, smaller amplitude of such changes were always accompanied by greater distance from shores. In this paper, two salt-freshwater interfaces were identified, namely, a large wedge-shaped interface and an inverted U-shaped one located at K5 (monitoring point). The critical hydraulic gradient of saltwater intrusion was between 0.0345 and 0.0377. Apart from that, mathematical and physical models were adopted to measure the influence of tides, showing a inverse proportion to the hydraulic gradient In addition, characteristics of ionic components can prove that K^+ was adsorbed and Ca^2+ was displaced during saline intrusion, while a reverse process was witnessed during desalting. In summary, cation exchange adsorption plus other complex physical chemical effects would take place during saltwater intrusion.