Use of Triple-Exposure X-ray Computed Tomography for Nondestructive Identification of Heavy Elements in Soil Samples

For the purpose of nondestructive measurements hazardous heavy-element-containing substances in soil samples, emerging technique, triple-exposure X-ray computed tomography (CT), is proposed. The use triple exposure (i.e. three different acceleration voltages for tube) improves accuracy identification atomic number a heavy element. With lead as target element, virtual microtomography simulations utilizing polychromatic source accelerated at 70, 100, and 140 kV were performed. CT images reconstructed on computer clayey samples with natural minerals, namely galena (PbS), witherite (BaCO3), stibnite (Sb2S3), sphalerite (ZnS), magnetite (Fe3O4). Quantitative analysis was performed to obtain following results. (i) Galena can be distinguished from other minerals witherite, stibnite, sphalerite, magnetite). (ii) content estimated reasonable accuracy. These successful results demonstrate that technique promising characterization contaminated elements such lead.