نوع مقاله : مقاله پژوهشی

نویسندگان

1 شرکت پسمانداری صنعت هسته‌ای ایران، سازمان انرژی اتمی ایران، کد پستی: 1439955931، تهران- ایران

2 پژوهشکده چرخه سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 8486-11365، تهران- ایران

3 پژوهشکده کاربرد پرتوها، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 3486-11365، تهران- ایران

چکیده

اندازه‌­گیری ضرایب توزیع یکی از ضروری­‌ترین تمهیدات در تحلیل ایمنی پسماندگاه­‌ها و مدیریت ایمن پسماند‌های پرتوزا است. نظر به اهمیت و ویژگی­‌های هسته پرتوزای توریم، در این مطالعه ضریب توزیع توریم در خاک آبرفت پسماندگاه انارک به روش ناپیوسته تعیین شد و دو پارامتر غلظت توریم و دانه‌­بندی خاک مورد مطالعه قرار گرفت. هم‌­چنین رفتار جذبی توریم نیز به روش پیوسته با بررسی اثر غلظت توریم و ارتفاع خاک مطالعه شد. مقدار میانگین ضریب توزیع توریم در خاک مذکور با استفاده از روش ناپیوسته برابر با L/kg 110960 محاسبه گردید. بررسی رفتار جذبی به روش پیوسته حاکی از جذب سطحی بالای توریم در خاک در نتیجه پیوند قوی ایجاد شده بین یون و جاذب بود. نتایج نشان داد که با کاهش اندازه ذرات خاک، ضریب توزیع افزایش می‌­یابد. در خصوص بررسی اثر غلظت در ضریب توزیع توریم، در محدوده آزمایش شده، ابتدا روند افزایشی و سپس روند کاهشی مشاهده ­گردید. نتایج به‌‌دست آمده در این پژوهش با نتایج سایر مطالعات انجام شده بر روی هسته پرتوزای توریم مقایسه شد که تطابق خوبی را با سایر مطالعات نشان داد.

کلیدواژه‌ها

عنوان مقاله [English]

Distribution coefficient determination of thorium on alluvium soil of Anarak Nuclear Repository

نویسندگان [English]

  • A.M. Taherian 1
  • A. Maleki 1
  • S. Zolghadri 2
  • H. Yousefnia 3
  • Z. Shiri-Yekta 2
  • S. Sarfi 2
  • H. Aghayan 2
  • S. Momenzadeh 1

1 Iran Radioactive Waste Company, AEOI, Postcode: 1439955931, Tehran - Iran

2 Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 11365-8486, Tehran-Iran

3 Application Radiation Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 11365-3486, Tehran-Iran

چکیده [English]

Calculation of distribution coefficients is one of the essential provisions in the safety assessment of radioactive waste repository and safe management of radioactive waste. Due to the importance and characteristics of thorium radionuclide in radioactive waste inventory, the distribution coefficient of thorium in the alluvium soil of Anarak Radioactive Waste Repository was determined by the Batch method two parameters of thorium concentration and soil granulation were studied. Also, the Flow-Through method studied the adsorption behavior of thorium has investigated the effect of thorium concentration and soil height. The average value of thorium distribution coefficient in Anarak soil was calculated 110960 L/kg using the Batch method. The study of adsorption behavior by the Flow-Through method demonstrated high uptake of thorium in the soil due to the strong bond created between the ion and the adsorbent. The results showed that the distribution coefficient increases with the decrease of soil particle size. Regarding the effect of concentration on the thorium distribution coefficient, first, an increasing trend and a decreasing trend were observed in the test range. The results obtained in this study were compared with the results of other studies on thorium radionuclide, which showed a good agreement with other studies.

کلیدواژه‌ها [English]

  • Distribution Coefficient
  • Thorium
  • Repository
  • Anarak
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