Issarapanacheewin Sudarat, Choomjun Dechanun, Katekaew Witsanu, Prasertchiewchan Nikom, Kingkam Wilasinee
Radioactive Waste Management Center, Thailand Institute of Nuclear Technology (Public Organization), Ongkharak, Nakhon Nayok, 26120, Thailand.
Nuclear Technology Research and Development Center, Thailand Institute of Nuclear Technology (Public Organization), Ongkharak, Nakhon Nayok, 26120, Thailand.
Heliyon. 2024 Jul 1;10(13):e33923. doi: 10.1016/j.heliyon.2024.e33923. eCollection 2024 Jul 15.
This study evaluated the potential of an immobilization technique to inhibit the migration and dispersion of Cs-137 contaminated electric arc furnace dust (EAFD) into the environment, by investigating its compressive strength and leaching characteristics. The EAFD was employed to replace ordinary Portland cement (OPC) in varied ratios, ranging from 0 % to 50 % by weight. The replacement was done using various water-binder ratios of 0.35, 0.40, 0.45, and 0.50. Furthermore, the use of activated carbon (AC) has been shown to minimize radionuclide and heavy metal discharge related to its high porosity. AC was added at weight concentrations of 0.5 %, 1.0 %, 1.5 %, and 2.0 %. Compressive strength and leaching tests are used to assess the long-term stability of waste forms and the effectiveness of immobilizing radioactive wastes, which is beneficial for storing and disposing of radioactive waste. The compressive strength is affected by the amount of EAFD, water-to-binder ratios, the addition of AC, and the duration of curing. Measurements of specific surface area, pore size, pore volume, and porosity were also carried out under various conditions. The research results indicate that the addition of AC improves the compressive strength and decreases the release of Cs-137 and heavy metals from the specimen. The mixture of 45 % EAFD and 1.5 % AC is appropriate for efficiently immobilizing Cs-137 contaminated EAFD.
本研究通过研究一种固定技术的抗压强度和浸出特性，评估其抑制Cs-137污染的电弧炉粉尘（EAFD）向环境中迁移和扩散的潜力。采用EAFD以0%至50%（重量）的不同比例替代普通硅酸盐水泥（OPC）。替代时使用了0.35、0.40、0.45和0.50的各种水胶比。此外，已表明使用活性炭（AC）可因其高孔隙率而使放射性核素和重金属排放降至最低。AC的添加重量浓度为0.5%、1.0%、1.5%和2.0%。抗压强度和浸出试验用于评估废物形式的长期稳定性以及固定放射性废物的有效性，这有利于放射性废物的储存和处置。抗压强度受EAFD的用量、水胶比、AC的添加量以及养护时间的影响。还在各种条件下进行了比表面积、孔径、孔体积和孔隙率的测量。研究结果表明，AC的添加提高了抗压强度，并减少了Cs-137和重金属从试样中的释放。45%的EAFD与1.5%的AC的混合物适合于高效固定Cs-137污染的EAFD。
