Risk assessment of radioactive hazards associated with black sand upgrading processes

Abstract

Black sands represent a good source of economic minerals with various industrial applications. However, their radioactive properties may prevent their use in specific applications. In this study, zircon, ilmenite, magnetite, and rutile are four minerals represent more than 75% of the black sand content, were selected to evaluate their Intrinsic radiological properties. The chemical composition of these minerals was determined along with their density and particle size. Then, the activity concentrations of the naturally occurring radioactive nuclides were experimentally determined and the most important radiological hazard indices were calculated. The results indicated that the upgrading process concentrates the natural radioisotopes in some minerals like the zircon and rutile leaving the magnetite and ilmenite with lower content than permissible limits. Moreover, the risk analysis identified the dangerous conditions and situations and suggest possible solutions to reduce these hazardous situations to a minimum and to keep a safe environment for the workers.