Neutron Technology
Did you know?
Physics offers many ways to create these small and electrically neutral elementary particles called neutrons. In industry, which is constantly looking to reduce the size of instruments, neutrons can be obtained either from a number of specific radioactive materials or from compact electric generators.
Radioactive sources are created artificially in some nuclear reactors as by-products, for example Californium (252Cf) or Americium Beryllium (Am-Be). These radioactive sources emit constantly but their neutron intensity decreases over time, with decay times varying from years to centuries, unlike neutron generators.
In the 1980s, Sodern pioneered the first civil neutron tubes to serve oil logging companies, followed by successive generations ensuring optimal solutions for the industry.
In 1990, the company developed advanced neutron generators for monitoring nuclear materials in waste reprocessing plants, now essential for waste characterization.
The 2000s marked the launch of the first neutron generator-based Cross-Belt Analyzer (CNA) in a cement plant; today, over 250 CNAs operate in more than 40 countries across cement, nickel, copper, and other sectors, enabling real-time quality monitoring on production lines. Sodern continues to innovate with the FastGrade downhole tool for geochemical logging in mining.
Neutron production
Neutron generators are miniaturized particle accelerators that make use of the fusion between hydrogen isotopes to produce neutrons similar to the reaction that sustains the sun. Two nuclear reactions are mainly used for producing neutrons electrically: Deuterium-Deuterium (DD) and Deuterium- Tritium (DT).These two reactions both result in the creation of Helium and the required neutrons. DD neutrons are slower than DT neutrons, which travel at about 5cm/ns due to their higher creation energy of 14MeV.
Fast neutrons are a major advantage for analytical techniques as they can penetrate many materials for in-depth measurement. Because neutron generators are voltage controlled, emission can be halted at any time and their inherently safe operation makes them an attractive instrument for almost every conceivable field of scientific inquiry.
Neutron tubes
A neutron tube is a miniaturized particle accelerator, in which we carry out nuclear fusion reactions to generate neutrons on-demand.
- In the tube, the deuterium/tritium mixture is trapped as a solid and released as a gas ;
- The gas is then ionized in an ion source ;
- The ions can then be accelerated in the accelerator using an electrical field ;
- This acceleration provides the energy the ions need to trigger the fusion reaction within the target, which also contains solid deuterium and tritium.
For this reaction to take place, the tube must be under ultra-high vacuum. The tube must also be completely sealed so that the internal pressure level can be controlled. It must also be electrically isolated from its environment so that a very high acceleration voltage can be applied.
What is PFTNA ?
Pulsed Fast and Thermal Neutron Activation (PFTNA) technology provides a rapid chemical analysis of large volumes of material, with no need for sampling. The PFTNA analysis is capable of measuring virtually the entire volume of material carried on a conveyor belt and of providing a batch analysis in just a few minutes. More recent developments are using the PFTNA analysis technique to measure the composition in mining boreholes.
energy levels.
How does it work?
PFTNA analysis uses a Pulsed Electric neutron generator to supply the neutron pulses which interact with the nuclei of the atoms. In turn, the atoms emit gamma rays with characteristic energy levels. These gamma rays are then measured by scintillation detectors and very fast digital pulse processing boards, in order to collect each photon individually and build up the emitted gamma ray spectrum. The spectra are interpreted using learning algorithms and the various element concentrations are transmitted to the user simply and rapidly.
Using an electric neutron source is a guarantee of the system’s stable analytical performance, owing to the constant emission of neutrons throughout its lifecycle. This significantly reduces the number of periodic calibrations needed, which are often difficult to conduct onsite and which always get in the way of the production process.
