انتقال و زوال طبیعی سیانور در خاک: مطالعه موردی دشت موته

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشیار، دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان

2 دانشجوی کارشناسی ارشد مهندسی عمران، مهندسی محیط زیست، دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان

3 استادیار، دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان

چکیده

سیانور نامی است که به ترکیبات دارای گروه -CN اطلاق می‌شود. مقادیر بیش از حد مجاز آن برای انسان و دیگر موجودات زنده، سمی قوی و آنی محسوب می‌شود. تعدادی از صنایع و معادن در فرآیند تولیدشان از سیانور استفاده می‌کنند که نهایتاً در مواد زائد آنها ظاهر خواهد شد و در صورت عدم تصفیه می‌تواند موجب آلودگی محیط زیست گردد. هدف این تحقیق، بررسی انتقال و زوال طبیعی سیانور در خاک اطراف منابع آلودگی است که برای این منظور، خاک دشت موته، در مجاورت معدن و کارخانه طلای موته، واقع در استان اصفهان، مورد مطالعه قرار گرفت. هشت چاه دستی به عمق 6 متر حفاری و از هر 0/5 متر عمق یک نمونه خاک برداشت شد. تحلیل آماری نتایج نشان داد که غلظت سیانور خاک، با دور شدن از منبع آلودگی کاهش و با افزایش عمق خاک افزایش می‌یابد. مشاهده شد که مدل رگرسیون با شدت توانی برای فاصله و نمایی برای عمق، به خوبی قادر به پیش‌بینی غلظت سیانور در خاکهای آلوده اطراف منابع آلودگی است. با کم شدن عمق خاک، سرعت فرآیندهای زوال طبیعی سیانور به طور قابل ملاحظه‌ای افزایش می‌یابد، لذا عمل زیر و رو کردن (شخم زدن) خاک در محلهای آلوده، برای سرعت بخشیدن به پاک‌سازی طبیعی آنها، توصیه می‌شود.

کلیدواژه‌ها


عنوان مقاله [English]

Transport and Fate of Cyanide in Soil : Case Study of Mooteh Valley

نویسندگان [English]

  • Amir Taebi 1
  • Ali Reza Zade Bafqi 2
  • Majid Sartaj 3
1 Associate Professor, Dept. of Civil Engineering, Isfahan University of Technology.
2 Grad Student of Civil and Environmental Engineering, Detpt. of Civil Engineering, Isfahan Univerisity of Technology
3 Assistant Professor, Dept. of Civil Engineering, Isfahan University of Technology
چکیده [English]

Cyanide, a generic term referring to all compounds containing the cyanide group –CN, is a highly potent and fast-acting poison to humans and other living organisms when exposed to high levels. Cyanide is a widely and essential chemical used in mining and minerals processing industries and many other industries such as metal processing and production of organic chemicals. While some industrial cyanide-containing wastes are treated or recovered, there are cases such as certain gold extraction plants where wastes are released in the environment. The objective of this research is to study the transport and fate of cyanide in soil in vicinity of a specific pollution source. For the purpose of this study, Mooteh valley, in the vicinity of Mooteh gold mine and factory, in the north of Isfahan province, Iran, was investigated. In Mooteh's Plant, the cyanide-containing waste (slurry tailings) is discharged to tailings ponds and there is potential for cyanide to migrate from them. Eight boreholes with 6 m depth were dug and from every 0.5 m a soil sample was taken. Statistical analysis of the results show that soil cyanide concentration decreases with distance from the tailings ponds (as a pollution source) and increases with depth. A regression model consisting of a power term for distance and an exponential term for soil depth can appropriately predict the soil cyanide concentration in the vicinity of a pollution source. As soil depth decreases, the rate of natural cyanide fate processes considerably increases. So, soil turn over practices is recommended to improve remediation of polluted sites

کلیدواژه‌ها [English]

  • Cyanide
  • Natural Degradation
  • Cyanide Fate
  • Gold Mine Tailings
  • Tailings Pond
  • Pollution Transport
  • Soil pollution
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