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The objective of this study was to investigate the effect of the addition of residue from the production of TiO2, namely, unreacted ore waste (UOW), on the properties of coating mortars as well as evaluate its radiological impact. The properties of the mixed cement lime mortars were evaluated after the addition of 5%, 10%, and 15% of UOW, in relation to the cement mass, with respect to the reference mortar. The coating mortars were evaluated for rheology, dynamic elastic modulus, and mechanical strength. Tests in the applied state were performed using panels. From the point of view of radiological protection, the concentration of natural radionuclides in the residue, components of the mortar, and ready mortar were determined. In addition, the concentration of radon in the air and the exposure of dwellers living in a standard room coated with mortar were evaluated. The results obtained indicated that UOW did not compromise the use of coating mortars, presenting no significant effect on the properties of fresh, hardened, and applied states. Although the UOW presented high concentration of radionuclides, mortars with 5%, 10%, and 15% of UOW led to a gamma exposition and indoor radon concentration (average values of 0.20 mSv.a-1 and 71 Bq.m−3, respectively) below the recommended limits (1 mSv.a-1 and 100 Bq.m−3). Thus, it is concluded that UOW can be incorporated into coating mortars without presenting risks to the health of users due to radiation exposure. |
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