Removal efficiency of 137Cs from radioactively contaminated electric arc furnace dust using different solvents

An advertent meltdown of radioactive source during steel smelting generates electric arc furnace dust (EAFD) polluted with 137Cs. The removal efficiency of 137Cs from EAFD was assessed by the lixiviation method using different solvents and at various radioactivity levels. More than 90% of 137Cs was removed from EAFD by rinsing with 0.5 M HNO3 and H2SO4, while removal efficiencies of deionized water, tap water, CsCl and Ca(OH)2 ranged from 84 to 89%. Mass loss and composition of the EAFD samples were investigated and compared. Results can assist in the decision-making of different solvents for large-scale removal of 137Cs from EAFD

Management of 137Cs in electric arc furnace dust by solid-liquid extraction and treatment of contaminated wastewater using co-precipitation

Efficient decontamination of 137Cs in electric arc furnace dust (EAFD) was carried out using a solid-liquid extraction method and then the obtained wastewater contaminated with 137Cs was treated by a co-precipitation. The influences of pH, stirring time, settling time, and different radioactivity on removal efficiency were assessed. Depended on the initial concentration and the solid-liquid ratio, it is possible to reduce around 93–96% radioactivity from EAFD, meanwhile the removal efficiency of 137Cs from wastewater exhibits in excess of 99%. After treatment, the final solution was certified safe from 137Cs, while the radioactive sludge could be stored safely

Determination of X-ray and gamma-ray shielding capabilities of recycled glass derived from deteriorated silica gel

We determined the radiation shielding properties for 10CaO–xPbO–(90-x) deteriorated silica gel (DSG) glass system (x = 20, 25, 30, 35, 40, and 45 mol.%). The mass attenuation coefficient (MAC) has been estimated at photon energies of 74.23, 97.12, 122, 662, 1173, and 1332 keV using a narrow beam X-ray attenuation and transmission experiment, the XCOM program, and a PHITS simulation. The obtained MAC values were applied to estimate the half value layer (HVL), mean free path (MFP), effective atomic number, and effective electron density. Results show that the MAC value of the studied glasses ranges between 0.0549 and 1.4415 cm2/g, increases with the amount of PbO, and decreases with increasing photon energy. The HVL and MFP values decrease with increasing PbO content and increase with increasing photon energy. The recycled glass, with the addition of PbO content (20–45 mol.%), exhibited excellent radiation shielding capabilities compared to standard barite and ferrite concretes and some glass systems. Moreover, the experimental radiation shielding parameters agree with the XCOM and PHITS values. This study suggests that this new waste-recycled glass is an effective and cost-saving candidate for X-ray and gamma-ray shielding applications