南疆咸水结冰与融化过程中盐分及离子的变化  

Changes of salt and ions in the process of salt water freezing and melting in Southern Xinjiang

作　　者：王海瑞 王兴鹏[1,2] 李朝阳[1,2] 马嘉莹 王学成 杨玉辉[1,2,3] WANG Hairui;WANG Xingpeng;LI Zhaoyang;Ma Jiaying;WANG Xuecheng;YANG Yuhui(College of Water Resources and Architectural Engineering,Tarim University,Alar,843300,China;Key Laboratory of Modem Agricultural Engineering,Tarim University,Alar,843300,China;Farmland Irrigation Research Institute,Chinese Academy of Agricultural Sciences,Xinxiang Henan,453000,China)

机构地区：[1]塔里木大学水利与建筑工程学院,阿拉尔843300 [2]塔里木大学现代农业工程重点实验室,阿拉尔843300 [3]中国农业科学院农田灌溉研究所,新乡453000

出　　处：《环境化学》2022年第4期1392-1400,共9页Environmental Chemistry

基　　金：中央支持地方高校基金(TDZKYB202001);塔里木大学校长基金创新团队项目(TDZKC202002);大学生创新创业训练计划项目(202010757047);中国农业科学院基本科研业务费专项(FIRI2019-02-0105)资助。

摘　　要：咸水淡化是缓解淡水资源紧张,减轻水体污染的有效途径.本试验分析了南疆农田排水不同冷冻温度下,结冰与融化过程中矿化度及离子浓度的分布规律;探讨了基于多级冷冻与重力脱盐条件下,盐分及Cl^(-)、SO_(4)^(2-)、K^(+)、Na^(+)的迁移规律成因.试验结果表明,冰融水矿化度与离子浓度随冷冻温度的降低而上升;不同温度处理下,各级冰融水矿化度与离子浓度相较于初始水样(F_(0))均显著降低(P<0.05),冰晶逐级冷冻过程中,冰融水矿化度与离子浓度逐渐升高;各离子进入冰晶的迁移速率存在差异,离子结冰比率拟合线斜率呈K^(+)>Cl^(-)>Na^(+)>SO_(4)^(2-)的分布规律.冰晶逐级融化过程中,冰融水矿化度、Cl^(-)、K^(+)、Na^(+)浓度呈现先快速下降、后缓慢下降、最终趋于平稳的变化趋势;SO_(4)^(2-)浓度下降趋势平稳.冰融水由最初的Na-Cl型咸水,逐渐转变成SO_(4)·Cl-Na型的微咸水.本文结论可为南疆咸水冷冻法淡化技术应用提供依据。Salt water desalination is an effective way to relieve the shortage of fresh water resources and water pollution.This article analyses the distribution of salinity and ion concentration during freezing and melting of farmland drainage in Southern Xinjiang under different freezing temperatures;which explains the migration reason of salt,Cl^(-),SO_(4)^(2-),K^(+),and Na^(+)under the condition of multistage freezing and gravity desalting.The results show that the salinity and ion concentration of ice melt water increase with the decrease of freezing temperature.Under the various temperatures,compared with the initial water sample(F_(0)),the salinity and ion concentration of ice melt water significantly decreased(P<0.05),during the gradual freezing of ice crystals,the salinity and ion concentration of ice melt water gradually increased.The migration rate of different ions getting into ice crystals is different,and the slope of fitting line of ion freezing ratio is K^(+)>Cl^(-)>Na^(+)>SO_(4)^(2-).In the process of melting ice crystals step by step the salinity of ice melt water,concentrations of Cl^(-),K^(+)and Na^(+)decrease rapidly first,then decrease slowly,and finally get stabilized.The concentration of SO_(4)^(2-)declines steadily.The ice melt water gradually changes from Na-Cl salt water to SO_(4)·Cl-Na brackish water.The conclusions of this article can provide a basis for the application of salt water freezing desalination technology in Southern Xinjiang.

关 键 词：咸水淡化 矿化度 离子迁移 结冰过程 融冰过程 

分 类 号：S276[农业科学—农业水土工程] X52[农业科学—农业工程]