NORM doesn’t sound like a big thing. But Naturally Occurring Radioactive Material might let the alarm bells ring. Everyone has heard of “radioactive material” and that sounds dangerous. However, most of this material is trapped deep in the ground beneath our feet. From there it reaches the surface, for example via the water cycle. Another possible pathway for NORM to reach the light of day is together with the so-called drilling mud during the drilling for energy commodities such as oil and gas. The good news: The low-level radioactive substances are not comparable with man-made nuclear waste. But to be able to completely rule out a harmful effect from NORM sludge it must be disposed of safely. Legally, this is only possible if the waste is free from other compounds such as water, oil or mercury. At this point econ’s VacuDry® technology can help clean the waste and also reduce its volume for disposal.
Matter in the course of time
The known world is composed of 91 chemical elements. Another 27 elements have been produced artificially in laboratories. The nuclei of each element have a very specific number of protons. To be a complete atomic nucleus however the neutrons are essential. Their number can vary within an element. This means that one and the same substance can have several so-called nuclides. A total of about 3,300 different nuclides are known to this day.
Most of them – namely 3,050 – change over time and with them the elements change as well. For example: Uranium (234U) converts to thorium (230Th), which decays to radium (226Ra) and so on. At the end of a long chain the stable lead (206Pb) remains. Some steps in this chain run at incredible speed. Other steps need a whole era to pass.
However, they all have one thing in common: The so-called radioactive decay releases energy in form of particles (alpha and beta radiation) or electromagnetic waves (gamma radiation) – the radioactive radiation. The high-energy gamma radiation penetrates even steel plates of several centimeter thickness. Alpha and beta radiation, however, can be shielded by a sheet of paper or a thin sheet of metal. But if the radioactive material enters the human body – e.g. via food, water or air – it may cause considerable damage. Because the radiant energy is sufficient to destroy parts of the genetic material inside the somatic cells. The consequences: cancer, mutation or even death.
NORM – The legacy of past stars
Naturally occurring radioactive material is much older than mankind, older than the Earth, even older than the solar system. The nuclides have their origin billions of years ago during the agony of earlier stars. That they even radiate today is due to the extremely long half-life period. In physics, this is the period in which half of a radioactive substance has decayed, giving off radiation. Thorium-232 for example has a half-life period of 14 billion years, uranium-238 and 235 are around 4.4 billion and 0.7 billion years, respectively and potassium-40 has a half-life period of 1.3 billion years. Mainly these four nuclides spread in the depths of the earth’s crust and especially granite has an increased content of uranium and thorium.
Purification and volume reduction with VacuDry®
If heavy drilling equipment penetrates such layers in search of oil and natural gas, these radioactive substances come to the surface as part of the drilling mud. It is increasingly difficult to find safe and sustainable disposal options. Due to environmental and health considerations, NORM Waste, which is impacted by water, drilling oil and other contaminants such as mercury cannot easily be disposed of without prior treatment.
This is where econ’s VacuDry® technology can provide a solution. The vacuum distillation process separates all liquid and volatile components such as water, hydrocarbons or mercury effectively from the radioactive waste. The nuclides themselves or the intensity of the radiation is not affected through the process but the volume of the polluted material is significantly reduced. The dry and clean NORM waste is stabilized with cement to prevent the material from leaching and is disposed of safely.
VacuDry® is not only a great help in current drilling projects in the oil and gas industry. It can also be utilized to treat previously deposited drilling muds in order to eliminate the risk to human health and the environment from the contained naturally occurring radioactive material.