APPLICATION OF DOSE AND ACTIVITY CRITERIA TO RADIOLOGICAL RISK ASSESSMENT DUE TO RADIONUCLIDES FROM RADIOACTIVE ASHES OBTAINED BY PIT COAL BURNING ON VALEA JIULUI, USED AS ADDITION TO PRODUCTION OF BUILDING MATERIALS

摘要

The Valea Jiului carboniferous basin is a constant supplier of pit coal necessary to thermal power stations from adjacent areas, the most known is Mintia-Deva. The article presents the results obtained to radioactive determination of the following components who leads to buildings materials obtaining: coal from Valea Jiului, electrofilter ashes obtained by coals burning in Mintia Deva thermo power station, cements prepared with electrofilter ash addition. The coal radioactivity was determined by measurements of debit gamma dose and radon concentration (in Bq/m~3). The radioactivity of electrofilter ash is determined by quantitative analyze for Ra226, Th232 and K 40 concentrations, elements who enters into radioactive index formula of substance. The cements radioactivity is determined by quantitative analyze of the same elements (Ra226, Th232 and K40). Finally, the quantitative proportion on prepared cements with ash obtaining by coals burning must not exceed 30%, so the index radioactive not exceed RI=0.4 (in Romania, RI_(max)=0.5).