مطالعه تجربی روش‌های شیمیائی حذف آلاینده‌ها در فرآیند بایر

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه آزاد شاهرود

2 دانشگاه علم و صنعت ایران

چکیده

در این تحقیق عوامل موثر در ایجاد آلاینده‌های کربنات و اگزالات در فرآیند بایر مجتمع آلومینای جاجرم تعیین شده است. در حذف شیمیایی کربنات و اگزالات سدیم محلول در لیکور آلومینات سدیم به طور جداگانه از آلومینات باریم با ساختارهای Ba2Al2O5، Ba2Al4(OH)16 و BaAl2O4، آلومینات کلسیم (Ca3Al2(OH)12) و فسفات سدیم (Na3PO4) و آهک استفاده گردید. بررسی اثر دما، غلظت سود کاستیک، آلومینا و کربنات سدیم نشان داد، استفاده از آلومینات باریم با ساختار Ba2Al4(OH)16 با راندمان 2/80 % حذف کربنات و استفاده از فسفات سدیم و آهک با راندمان 1/56% در حذف اگزالات بیشترین راندمان را دارا می‌باشند. نتایج همچنین نشان دادند 9/66% کربنات ورودی از آهک بوده و بوکسیت نیز عامل 9/99% از اگزالات سیکل بایر می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Experimental Study of Pollutant Removal Chemical Techniques in the Bayer Process

نویسندگان [English]

  • Mostafa Mahmoudian 1
  • Ahad Ghaemi 2
  • shahrohk Shahhosseini 2
1 Shahroud university
2 Iran university of science and technology
چکیده [English]

In this work, carbonate and oxalate creating factors were determined in the Bayer process. In the chemical removal of carbonate and sodium oxalate soluble in sodium aluminate liquor, barium aluminate with structures of Ba2Al2O5, Ba2Al4(OH)16 and BaAl2O4, calcium aluminate (Ca3Al2(OH)12), sodium phosphate (Na3PO4) and lime were separately used. Investigation of temperature, concentration of caustic soda, Al2O3 and sodium carbonate revealed that using barium aluminate with the structure of Ba2Al4(OH)16 with the removal efficiency of carbonate equal to 80.2% and sodium phosphate (Na3PO4) and lime with the removal efficiency equal to 66.9% in oxalate removal, have maximum efficiency. The results also showed that lime and bauxite lead to 66.9 and 99.9% of carbonate and oxalate pollutions in Bayer process liquor, respectively.

کلیدواژه‌ها [English]

  • Bayer Process
  • Carbonate
  • Oxalate, Pollutant
  • Chemical Technique
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