Abstract:
The objectives of this research were to study the specific activity of petroleum waste from the petroleum industry in Thailand, as well as its correlation to barium, strontium and calcium contents. The petroleum waste samples include sludge and scale from Bongkot gas field and Sirikit oil field. In this study, the specific activities of [superscript 226]Ra and [superscript 228]Ra in sludge and scale samples were determined by gamma-spectroscopy technique. Their chemical contents were analyzed by X-ray fluorescence technique. It was shown that in sludge samples, the average specific activities of [superscript 226]Ra and [superscript 228]Ra range from 0.27-2.45 and 0.35-2.06 pCi/g, respectively. The average specific activities of [superscript 226]Ra and [superscript 228]Ra in scale samples range from 0.25-119.91 and 0.31-140.07 pCi/g, respectively. Two samples of scale from Sirikit field had average specific activity level of radium 100 times higher than the level that found in the local soil. In addition, the positive correlation was found between the specific activity level of radium and chemical composition; barium, strontium and calcium; contained in sludge and scale sample.