The concentrations of Natural Radioactivity in Fly Ash Released from Al-Dura thermal Power Plant in The south of Baghdad City

Abstract

The concentrations of naturally radioactive made occurring and technically enhanced radioisotopes of fly ash samples, collected from Al-Dura thermal power Plant- south of Baghdad, have been investigated using the NaI(Tl) gamma-ray spectroscopy. The average Activity concentrations of the radio elements 238 U, 232Th and 40K in Fly ash samples are measured accurately and found to be 33.860, 32.6 and 644.64Bq/kg respectively. On the whole the radionuclide's concentrations are still below the global average of 50 Bq/kg for 238U and 232Th, but are much higher in 40K, relative to the global average, about 500 Bq/kg. The absorbed gamma doses in air, due to naturally occurring radionuclides in fly ash samples, are measured and found within the range; from 46.863 to 86.358 nGy h-1, which is higher than the world average, about 43 nGy h-1. As well as Fly Ash samples have had Radium equivalent activity (Raeq) with an average is about 138.82 Bq/kg. The radiation hazard indexes are calculated based on the above results and found lower than the maximum value. The overall average values of the Hex and Hin indices have been found to be 0.37and 0.32 respectively. Also, the overall average value of the representative gamma index (Iγr) for all fly ash samples is about 1.037, which are greater than the unity (>1). In this case, treatments to the NORM released from that station must be done.