Assessment of radiation hazard indices from evaporated ponds in petroleum industry

الملخص EN

There are various national, international regulations and guidelines on radiation protection in general and NORM in particular.

Radiation dose to humans from NORM and TENORM largely driven by radium isotopes from the U-238 and Th-232 decay chains.

The radiological effects due to one of the nearest evaporated pond (about 80 km from Cairo) were evaluated in this study.

The radiation hazard indices and the annual effective doses equivalent were measured.

The average activity concentrations of 226Ra, 232Th and 40K (Bq/kg) in the collected samples were 16.10±0.14 kBq/kg, 13.87±0.13 kBq/kg and 6.27±0.15 kBq/kg respectively.

The mean values of radium equivalent were ranged between 95.07±0.21 kBq/kg and 13.19±0.32 kBq/kg.

The calculated absorbed dose rates were ranged between 42.58 and 5.93 μGy/h.

These average values give rise to a mean effective dose of about 8.33 mSv/y, which is greater than the annual dose rate recommended by the International Commission on Radiological Protection (Radiation Protection: 1990 Recommendations of the International Commission on Radiological Protection, Pergamon Press, Oxford, 1990) as the maximum annual dose to members of the public.

In addition, the internal and external hazard index were greater than unity, which attributed to the high activity concentration of 226Ra and its progenies.

This study aimed to develop a strategy for raising awareness of NORM issues, both in relevant industries and with the public generally.

Also, to develop national guidance on strategies and criteria for the treatment and disposal of NORM arising from various process waste streams, including by landfill or land spreading.