Assessment of environmental radioactivity of TE-NORM produced from petroleum production facilities

الملخص EN

Currently the excessive accumulation of Naturally Occurring Radioactive Materials (NORM) in different environmental compartments is poses a risk to human health.

During the petroleum oil production process, NORM flows with the oil, gas and water mixture and accumulates in scale, sludge and scrap materials.

The aim of this work is to measure the activity concentrations of TE NORM sludge produce during cleaning operation of oil separators storage tanks and other surface equipment from one of the typical petroleum production facilities in Egypt.

Radioactive waste contains NORM, mainly from the natural radioactive series (238U, 235U and 232Th), together with potassium (40K).

The selected sludge samples collected from a typical petroleum production facility were counted, analyzed and investigated using HPGe detector Gamma ray spectrometer.

It was found that 238U, 235U, 226Ra, 232Th and 40Kconcentrations in the sludge samples ranged from (0.0- 350), (0.0- 22), (0.0-1722), (0.0- 187) and (0.0-3784) Bq/kg, respectively.

The calculated absorbed dose rate in sludge samples ranged from 13- 1922 nG/h.

The highest effective annual absorbed dose (EAD) of these samples reached to 2.36 mSv/y.

However, this value is higher than the permissible limit, 1mSv/y of (EAD), for public exposure but it is lower than that for workers 20mSv/y.

The values of (Raeq) for some sludge samples exceeded the recommended safety limit 370 (Bq/Kg).

In addition, the maximum external hazardous index (Hex) value of 11.2 is more than the unity permitted in (ICRP 103, 2007).