نقش بازگشت پذیری در لخته شدن فلزات سنگین در محیط مصبی

نوع مقاله: مقاله پژوهشی

نویسندگان

1 مهندسی محیط زیست-دانشکده نحصیلات تکمیلی محیط زیست-دانشگاه تهران-تهران-ایران

2 دانشکده تحصیلات تکمیلی محیط زیست- دانشگاه تهران

چکیده

پس از اینکه اولین بار فرآیند لخته‌سازی در مصب کشف شد، دگرگونی عظیمی در نحوه محاسبه بار محلول عناصر به وجود آمد. در واقع مشخص شد که در اثر اختلاط آب شیرین با شور، بخش قابل توجهی از عناصر در آب شیرین ‌به صورت لخته در آمده و در محیط مصب ته‌نشین می‌شوند. در این تحقیق با بررسی فرآیند لخته‌سازی در مصب رودخانه مشخص شد که فلزات کادمیم، کروم، کبالت و نیکل به ترتیب 86، 74، 62 و 50 درصد از بار اولیه خود در اثر اختلاط آب شور و شیرین در دهانه مصب از دست می‌دهند. از دست آوردهای جدید این تحقیق می‌توان به روش جدید در محاسبه بار فلزات اشاره کرد. این تحقیق برای اولین بار نشان داد که لخته سازی فرآیندی برگشت پذیر می‌تواند باشد. بعبارتی به دلیل تغییرات مدام فیزیکی و شیمیایی مصب، فلزات بطور پیاپی این امکان را دارند که از حالت لخته خارج شوند و به فاز محلول باز‌گردند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

The role of reversibility in flocculation of heavy metals in the estuarine zone

نویسندگان [English]

  • Ali Marefat 1
  • Abdolreza Karbassi 2
  • Mir babak Monzavi 2
1 faculty of environment, university of tehran, Tehran, Iran
2 faculty of environment, university of Tehran
چکیده [English]

After discover of flocculation process in estuaries, there was a significant change in calculation of dissolved metals load entering sea and other saline water environments through rivers. In other words, due to mixing of fresh and saline water in an estuarine zone, a significant amount of heavy metals flocculate and settle in the estuarine zone. In the present research, the flocculation process of heavy metals in Shfarud River is investigated during estuarine mixing with Caspian Sea water. Results indicated that that Cd, Cr, Co and Ni lose their initial load by 86, 74, 62 and 52 percent, respectively. Furthermore, an updated method, which is considered as one achievement, was used to simulate the estuary in this research. Actually, it is showed that flocculation process could be a reversible process. In other words, due to continuous chemical and physical change of estuary environment, flocs of metals might return to dissolve phase.

کلیدواژه‌ها [English]

  • pollution load
  • heavy metals
  • estuary
  • flocculation

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