Page 72 - 2017地大报告电子书

2017

qiangWang.

WATER RESEARCH 卷 : 109 页 : 337-346 出版年 : FEB 1 2017
摘 要：Severe health problems due to elevated arsenic (As) in groundwater have made it

urgent to develop cost-effective technologies for As removal. This field experimental study tested
the feasibility of in-situ As immobilization via As incorporation into newly formed biogenic

Fe(II) sulfides in a typical As-affected strongly reducing aquifer at the central part of Datong
Basin, China. After periodic supply of FeSO4 into the aquifer for 25 d to stimulate microbial

sulfate reduction, dissolved sulfide concentrations increased during the experiment, but the
supplied Fe(II) reacted quickly with sulfide to form Fe(II)-sulfides existing majorly as mackinawite

as well as a small amount of pyrite-like minerals in sediments, thereby restricting sulfide build-
up in groundwater. After the completion of field experiment, groundwater As concentration

decreased from an initial average value of 593 μg/L to 159 μg/L, with an overall As removal
rate of 73%, and it further declined to 136 μg/L adding the removal rate up to 77% in 30 d after

the experiment. The arsenite/Astotal ratio gradually increased over time, making arsenite to be
the predominant species in groundwater residual As. The good correlations between dissolved

Fe(II), sulfide and As concentrations, the increased abundance of As in newly-formed Fe sulfides
as well as the reactive-transport modeling results all indicate that As could have been adsorbed

onto and co-precipitated with Fe(II)-sulfide coatings once microbial sulfate reduction was
stimulated after FeSO4 supply. Under

the strongly reducing conditions, sulfide
may facilitate arsenate reduction into

arsenite and promote As incorporation
into pyrite or arsenopyrite. Therefore,

the major mechanisms for the in-situ As-
contaminated groundwater remediation

can be As surface-adsorption on and co-
precipitation with Fe(II) sulfides produced

during the experimental period.
论文链接：https://doi.org/10.1016/j.watres.2016.10.056

3.Intrawellbore kinematic and frictional losses in a horizontal well in a bounded

confined aquifer
作 者 : Wang Quanrong; Zhan,Hongbin*.

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