地下水环境中铁-砷运移与氧化现场模拟研究  

Site Simulation on the Migration and Oxidation of Iron-arsenic in Groundwater Environment

作　　者：邓博[1] 邓天天[2] 李义连[1] 

机构地区：[1]中国地质大学(武汉),湖北武汉430074 [2]湖北工业大学,湖北武汉430000

出　　处：《水生态学杂志》2013年第3期39-43,共5页Journal of Hydroecology

基　　金：863项目(2007AA06Z333)

摘　　要：砷在含水层中迁移、转化、释放等地球化学行为往往与地下水的氧化还原环境密切相关。本研究在山阴地区开展了为期1个月的现场模拟试验,模拟地下水环境中砷的运移,另外注入Fe(Ⅱ)溶液,同时连续曝气,以改变地下水的强氧化环境,从而达到As(Ⅲ)向As(Ⅴ)的转化并将其沉降固定的目的。试验结果表明As(Ⅲ)和As(Ⅴ)在地下水中的迁移速率是其在2mm砂质颗粒介质中的迁移速率的92.6和109.9倍,前者的速率要大于后者。在氧单独存在的情况下溶液中砷的含量变化甚小,而在加入Fe(Ⅱ)溶液以后,连续曝气的同时,Fe(Ⅱ)被氧化成Fe(Ⅲ),从而将As(Ⅲ)氧化成As(Ⅴ)并结合絮凝沉降使得砷的浓度明显降低。The geochemical behaviors referring to migration, transformation and release of Arsenic in the aquifer, release is often closely related to the oxidation-reduction environment of groundwater. This work of site simulation on the mitigation and oxidation of iron-arsenic has been carried out for a month in Sanyin area. We aim at achieving the conversion of As （Ⅲ） to As （Ⅴ） and leading to subsidence by injecting Fe （Ⅱ） solution and simultaneous continuous aeration to change the in situ strong oxidation environment of groundwater. Experimental results show that the migration rate of As （Ⅲ） and As （Ⅴ） in the groundwater is respectively 92.6 and 109.9 times of that in the sand medium with particles of 2 mm, and the rate of the former is faster than the latter. In the presence of oxygen alone, the change of arsenic content in the solution is very small. Injecting the Fe （Ⅱ） solution and simultaneous continuous aeration, however, the concentration of arsenic is significantly decreased because of the oxidation of As （Ⅲ） into As （Ⅴ） and combined with flocculation sedimentation as Fe （Ⅱ） is oxidized to Fe （Ⅲ）.

关 键 词：地下水 铁-砷运移 氧化 现场模拟 

分 类 号：X142[环境科学与工程—环境科学]