کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6386550 1627044 2014 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The impact of biostimulation on the fate of sulfate and associated sulfur dynamics in groundwater
ترجمه فارسی عنوان
تأثیر بیوسیستولاسیون بر سرنوشت سولفات و دینامیک گوگرد در آبهای زیرزمینی
کلمات کلیدی
کاهش سولفات، ایزوتوپهای پایدار، تجزیه ایزوتوپ، بارش سولفید آهن انحلال معدنی سولفات، دوباره اکسیداسیون سولفید،
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی
The impact of electron-donor addition on sulfur dynamics for a groundwater system with low levels of metal contaminants was evaluated with a pilot-scale biostimulation test conducted at a former uranium mining site. Geochemical and stable-isotope data collected before, during, and after the test were analyzed to evaluate the sustainability of sulfate reducing conditions induced by the test, the fate of hydrogen sulfide, and the impact on aqueous geochemical conditions. The results of site characterization activities conducted prior to the test indicated the absence of measurable bacterial sulfate reduction. The injection of an electron donor (ethanol) induced bacterial sulfate reduction, as confirmed by an exponential decrease of sulfate concentration in concert with changes in oxidation-reduction potential, redox species, alkalinity, production of hydrogen sulfide, and fractionation of δ34S-sulfate. High, stoichiometrically-equivalent hydrogen sulfide concentrations were not observed until several months after the start of the test. It is hypothesized that hydrogen sulfide produced from sulfate reduction was initially sequestered in the form of iron sulfides until the exhaustion of readily reducible iron oxides within the sediment. The fractionation of δ34S for sulfate was atypical, wherein the enrichment declined in the latter half of the experiment. It was conjectured that mixing effects associated with the release of sulfate from sulfate minerals associated with the sediments, along with possible sulfide re-oxidation contributed to this behavior. The results of this study illustrate the biogeochemical complexity that is associated with in-situ biostimulation processes involving bacterial sulfate reduction.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Contaminant Hydrology - Volume 164, August 2014, Pages 240-250
نویسندگان
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