Natural Radioactivity in Steel Slag Aggregate

Abstract

Present day steelmaking slags are being successfully used as a high quality mineral aggregate for the building industry.With this, it is of vital importance to be familiar with the technical significance of the secondary application of steel slag, because some steel slag might contain increased concentration of substances harmful to human health.In terms of steel slag impact on the environment, radionuclides are the least researched of all pollutants emitted from the metallurgical processes.This paper presents the results of radiochemical testing of steel slag and steel slag aggregates for the purpose of its use in the production of construction material.Obtained results of measurements show that 40 K, 226 Ra and 232 Th in all examined steel slag samples have the activity concentration from 45.3 to 62.9Bqkg -1 , 15.2 to 21.4Bqkg -1 and 12.9 to 15.4Bqkg -1 , respectively.Results of measurements of radionuclide activity concentrations of 226 Ra, 232 Th and 40 K in slag aggregates show similar values for all radionuclides ranges as follows: 40 K from 14.1 to 23.3Bqkg -1 ; 232 Th from 8.6 to 14.4Bqkg -1 and 226 Ra from 14.8 to 26.8Bqkg -1 .Activities index (I1, I2, I3) of 226 Ra, 232 Th and 40 K were compared with values recommended by Croatian legislation.Radium equivalent concentrations (Ra eq ) of 226 Ra, 232 Th and 40 K for examined steel slag and steel slag aggregates are harmounious with the results presented by other authors for the same by-product.The testing has been conducted on steel slag created during the production of carbon steel by electric arc furnace in Steel Mill of CMC Sisak, Croatia.Keywords: radioactivity, radionuclide, slag, aggregate, industrial by-product Obecnie żużle stalownicze są z powodzeniem używane do wytwarzania wysokiej jakości kruszywa mineralnego dla budownictwa.Z tego powodu, istotnego znaczenia nabiera znajomość wtórnego zastosowania żużli, ponieważ niektóre żużle mogą zawierać zwiększone stężenie substancji szkodliwych dla zdrowia ludzkiego.Pod względem wpływu żużli na środowisko, radionuklidy są najmniej