Asphaltene or Polyvinylchloride Waste Blended with Cement to Produce a Sustainable Material Used in Nuclear Safety

The current research uses sustainable methods to preserve the environment, such as exploiting municipal or industrial waste that may harm the environment. The wreckage of polyvinyl chloride (PVC) pipes and asphaltene are used as additives to cement to improve its mechanical properties, while stabilizing the radioactive waste resulting from the peaceful uses of nuclear materials, or enhancing its radiation shielding efficiency. New composites of Portland cement with ground PVC or asphaltene up to 50% are investigated. Fast neutron removal cross-section (ƩR) and gamma shielding parameters, such as mass attenuation coefficient (MAC), half-value layer (HVL), effective atomic number (Zeff), and exposure build-up factor (EBF) at wide energy range and thickness, are determined. The compressive strength and apparent porosity of the examined composites are examined to test the durability of the prepared composites as stabilizers for radioactive waste. The obtained results show that the bulk density of hardened cementitious composites was slightly increased by increasing the additive amount of PVC or asphaltene. The compressive strength of cement composites reached more than 4.5 MP at 50 wt.% PVC and 8.8 MPa at 50 wt.% asphaltene. These values are significantly higher than those recommended by the US Nuclear Regulatory Commission (3.4 MPa). Additionally, the obtained results demonstrate that although the gamma MAC is slightly decreased by adding asphaltene or PVC, the neutron removal cross-section was highly increased, reaching 171% in the case of 50 wt.% asphaltene and 304% in the case of 50 wt.% PVC. We can conclude that cement composites with PVC or asphaltene have optimized radiation shielding properties and can stabilize radioactive waste

Investigating the Effect of Gamma and Neutron Irradiation on Portland Cement Provided with Waste Silicate Glass

In this study, samples of commercial Portland cement mixed with 30% weight of crushed waste silicate glass were prepared in the shape of well-dried cylinders. Then, their physical and mechanical properties were investigated for two types of samples: samples without exposure and samples with exposure to gamma-ray and neutron irradiation. A notable deterioration of the physical properties of the irradiated samples relative to the non-irradiated ones was recorded. All the spectroscopic analyses were performed for the samples with exposure and without exposure to gamma-ray and neutron irradiation. The XRD emerging peaks of irradiated samples were studied to estimate the presence and stabilities of major peaks indicating the presence of the main compositions of cement with the amorphous nature of glass. FT-IR transmittance spectra were identified and the bonds were located close to those of identical glasses. Moreover, SEM images and EDX analysis were conducted on the two types of composite samples (without exposure and with exposure to gamma and neutron irradiation) to specify the change in the physical appearance and the chemical composition after irradiation. The attenuation parameters were computed theoretically with the assistance of Phy-X/PSD software to evaluate the gamma-ray and neutron shielding properties by defining the composition and the density of the samples. The irradiation was found to have a negative impact on the shielding ability of the prepared samples where there was an over-reduction in the parameters calculated with the probability that the damage may increase with longer exposure to the radiation

Asphaltene or Polyvinylchloride Waste Blended with Cement to Produce a Sustainable Material Used in Nuclear Safety

The current research uses sustainable methods to preserve the environment, such as exploiting municipal or industrial waste that may harm the environment. The wreckage of polyvinyl chloride (PVC) pipes and asphaltene are used as additives to cement to improve its mechanical properties, while stabilizing the radioactive waste resulting from the peaceful uses of nuclear materials, or enhancing its radiation shielding efficiency. New composites of Portland cement with ground PVC or asphaltene up to 50% are investigated. Fast neutron removal cross-section (ƩR) and gamma shielding parameters, such as mass attenuation coefficient (MAC), half-value layer (HVL), effective atomic number (Zeff), and exposure build-up factor (EBF) at wide energy range and thickness, are determined. The compressive strength and apparent porosity of the examined composites are examined to test the durability of the prepared composites as stabilizers for radioactive waste. The obtained results show that the bulk density of hardened cementitious composites was slightly increased by increasing the additive amount of PVC or asphaltene. The compressive strength of cement composites reached more than 4.5 MP at 50 wt.% PVC and 8.8 MPa at 50 wt.% asphaltene. These values are significantly higher than those recommended by the US Nuclear Regulatory Commission (3.4 MPa). Additionally, the obtained results demonstrate that although the gamma MAC is slightly decreased by adding asphaltene or PVC, the neutron removal cross-section was highly increased, reaching 171% in the case of 50 wt.% asphaltene and 304% in the case of 50 wt.% PVC. We can conclude that cement composites with PVC or asphaltene have optimized radiation shielding properties and can stabilize radioactive waste