Environmental Radiochemistry – NORM
At NCIMB we offer alpha and gamma spectrometry, along with characterisation and analysis of a range of NORM and LSA sample types.
Naturally occurring radioactive material
"NORM" stands for naturally occurring radioactive material. Radionucleotides occur naturally within the earths crust, and exposure to naturally occurring levels of radioactivity is not generally of concern. However, some human activity, such as coal mining and oil production, can result in accumulation of natural radioactivity within waste streams.
In industries where elevated levels of NORM are known to accumulate in waste materials, sampling and analysis is often required prior to their disposal.
NORM analysis for the oil and gas sector
While the long-lived uranium and thorium isotopes are not mobilised from rock formations during oil and gas production, the isotopes Ra-226, Ra-224, Ra228 and Pb-210 do appear in produced water.
These naturally occuring isotopes then precipitate out of the fluid flow, along with sulphate and carbonate as scale or sludge in pipes and other equipment. In this way, levels of radioactivity can become elevated in oil and gas production facilities.
At NCIMB, we use gamma spectrometry to report on the activity of radium and daughters (including lead-210) and undertake alpha spectrometry for the analysis of polonium-210. As polonium-210 and lead 210 exist in equilibrium, alpha spectrometry can also be used for analysis of lead-210 with extremely low detection limits. The prinipal decay series of concern are uranium-238 and thorium-232, which give rise to radium-226 and radium-228 respectively.
Oil and gas industry track record
Within the UKCS (United Kingdom Continental Shelf), prior to offshore disposal of NORM waste, a sample of the material must be taken and analysed to determine the types and levels of radioactivity present.
Additionally, OSPAR (the mechanism by which 15 governments and the EU cooperate to protect the marine environment of the North-East Atlantic) requires that for water jet and chemical descaling operations, samples of the scale/slurry produced are taken for analysis at the discharge point, while the operation is underway.
At NCIMB we have extensive experience of working with the oil and gas industry, and have developed a range of NORM analysis, chemical characterisation and testing services to meet the needs of this sector.
Our analytical services laboratories are based in Aberdeen, and we can accept a broad range of sample types for analysis, including scales, pig wax, sludge, sand and produced water.
Oilfield scale characterisation
Our customers often require characterisation of scales alongside NORM activity and we use ICP-mass spectrometry to offer a suite of tests for this purpose. Our standard package includes barium (Ba), silicon (Si), aluminium (Al), iron (Fe), calcium (Ca), strontium (Sr), potassium (K), sodium (Na), magnesium ( Mg), lead (Pb) and zinc (Zn).
Elemental results are combined with qualitative tests to report on the most likely compounds present.
We regularly receive pig wax samples for analysis, and our standard suite of tests includes NORM activity, water content, inorganic content, organic content and iron. We can also undertake a range of heavy metals analysis including lead (Pb), copper (Cu), cadnium (Cd), nicol (Ni), zinc (Zn) and mercury (Hg).