峡江水利枢纽同江河防护区地下水中铁离子运移规律分析

The Analysis on the Migration Law of Iron ions in the Ground Water within the Tongjiang River Protective Zone of Xiajiang Water Control Project

地下水铁离子浓度超标,将严重影响居民饮用水安全.认识地下水铁离子的运移规律,可为保护地下水饮用水源提供依据.本文基于溶质运移理论,建立同江河防护区内地下水铁离子运移概化模型,分析在同江河防护区与水库库区之间设置防护层与不设置防护层二种情况下铁离子的运移规律.分析表明,不设置防护层工况,铁离子浓度的变化呈现"钩状"形态发展,且运移速度快,扩散范围广;设置防护层工况,浓度的变化呈现"舌状"发展,运移速度、扩散范围远小于不设置防护层的情况;防护层会有效延缓铁的运移速度,限制运移范围,但不会从根本上解决铁的运移.

The overproof iron ionic concentration in the ground water which is used as the drinking water source is detrimental to residents＂ drinking water safety. Thus, studying its migration law could support the protection work of ground water which is used as the drinking water source. This paper aims to construct the iron ionic migration generalized model of ground water within the Tongjiang River protective zone so as to analyse the migration law of iron ions under the conditon that protective layers are installed or not between the Tongjiang protective zone and the reservoir area of Xiajiang Water Control Project . The results indicates that without protective layers, variation of iron ionic concentration appears to be a hook-like form of development with fast migration velocity and broad diffusion. Yet, with protective layers, variation appears to be a ligulate form with much slower speed and smaller diffusion range. Although the protective layers would effectively postpone the migration speed of iron ions and limit their migaration range, they could never solve the problem of iron ionic migration ultimately.