Assessment of Radioactive Concentrations in the Egyptian Natural Gas Grid and Their Relevant Impacts

Abstract

The radioactivity concentrations of 226Ra, 232Th and 40K in thirty samples representing the technically Naturally Occurring Radioactive Materials (NORM) in the Egyptian natural gas were investigated. The investigations were performed using a gamma ray spectroscopy technique. The obtained data were used to establish a data base for NORM concentrations during the different processing stages of natural gas and to estimate the associated radiation health hazard impacts. Great concern has been devoted to determine the specific activity of 210Pb as it represents all daughters originating from 222Rn that have relatively short half-lives. The samples were collected from the gas pipeline grid covering different areas in Egypt. Fifteen samples were taken from the gas pipelines, whereas the remaining samples were taken from the upstream facilities before pumping into the grid. The average activity concentrations of 226Ra, 232Th and 40k were found to be 16.2 ± 1.5, 10.50 ± 0.9 and 98.46 ± 6.03 Bq/kg for filter samples respectively. The corresponding average values for scale samples were 37.28 ± 3.1, 45.7 ± 2.6 and 621.79 ± 9.2 Bq/kg. The sludge samples gave average values of 14.97 ± 1.94, 9.99 ± 1.48 and 112.82 ± 5.82 respectively. These values are below the recommended international limits. In contrary, the average values of activity concentrations of waste water were found to be 4.895 ± 0.51, 2.241 ± 0.3 and 31.852 ± 2.31 Bq/kg respectively. The obtained results indicate that 226Ra content is higher than the recommended values for domestic or drinking water. Additionally, high values of the specific activity of 210Pb were found in both deposits and filter samples.