Nuclear Energy in Industry
Industry is one of the fields in which nuclear energy is used. The use of nuclear energy in modern industry in developed countries is very important for the improvement of industrial processes, for measurements and automation, and for quality control.
The use of nuclear radiation is applied in a wide range of activities. These activities can be quality control of raw materials of industrial processes (cement, thermal power plants, oil refineries, etc.), or quality control of products manufactured in series. In the case of series production, it is used as a prerequisite for the complete automation of high-speed production lines.
In the field of industry, irradiation with intense sources is often used to improve the quality of certain products (special plastics, sterilization of single-use products, etc.).
In addition, experiments are also carried out with tracers to obtain accurate and detailed information on the state of industrial equipment to opt for the extension of its useful life.
Nuclear sources of industrial use do not usually produce radioactive waste in the country that uses them, but in the country of the supplier. Once these sources are unusable, the commercial firm of the supplier country withdraws them when it is replaced.
Use of radioisotopes as tracers
The fact that small amounts of radioactive substances can be measured quickly and accurately, makes radioisotopes are used to follow processes or analyze the characteristics of these processes. These substances are called tracers.
Tracers are radioactive substances that are introduced in a certain industrial process. This action allows detecting the trajectory of these substances thanks to their radioactive emission. In this way, it is possible to investigate various variables of the industrial process (flows, leaks, etc.).
Some of the industrial applications of nuclear energy in which tracers are used are the following:
- Process research, being able to control the parameters of ventilation systems (flow rates, ventilation efficiency)
- For mixtures, checking the degree of homogeneity, the mixing time and the performance of the mixer
- Industrial maintenance processes, studying the transport of materials through pipes (leaks or leaks and flows)
- Detection of wear and corrosion, determining the degree of wear of materials (motors) and corrosion of processing equipment.
An isotope tracer is used in the field of chemistry and biochemistry to help understand chemical reactions and interactions. In this technique, one or more atoms of the molecule of interest are replaced by an atom of the same chemical element, but of a different isotope (the atomic nucleus is the same, but it has a different number of neutrons).
Since the substitute atom has the same number of protons, it will behave in almost the same way as the original atom and, with few exceptions, will not interfere with the reaction you want to investigate. However, the difference in the number of neutrons implies that it will be possible to detect it in a different way than the other atoms of the same element.
Quality control by scintigraphy
Gamma radiography is an application of nuclear energy in industry. This application constitutes an indispensable quality control technique for the verification of welds in pipes and for the detection of cracks in aircraft parts.
Industrial radiography allows volumetric tests on a material. The difference in thickness in each of the sections of a material causes a different penetration of the X or gamma radiation to which it is subjected.
To perform this test, a source of penetrating nuclear radiation is placed on one side of the material to be examined. On the other side is a radiation detector. In this way a two-dimensional image representative of the piece is obtained.
The radiographic interpretation consists in the analysis of the images obtained through the industrial radiography, in order to detect and evaluate possible defects in the inspected materials and thus ensure the required quality of said material or component inspected.
It is the most important application of the sources of iridium-192. The iridium-192 sources cover 95% of the non-destructive tests carried out in the quality control of foundry products, metal construction welding, etc. The rest of these controls are made with sources of cobalt-60 (for large thicknesses, up to tens of centimeters of steel) or with tulio-170 (for small thicknesses, of the order of millimeters).
Use of radiations in other industrial processes
Gamma radiation ionizes matter and creates free radicals, which are the intermediary species of many chemical reactions. Once the radiation (sources of cobalt-60) has been applied to the monomers with which the plastics are manufactured, the formation of large polymer chains is induced. From here, if the irradiation of the material is continued, special plastics with a high degree of catenary cross-linking are formed, which considerably improves their properties as thermal and electrical insulators. Thus, the degradation of some polymers induced by radiation, constitutes a useful property for certain types of packaging.
Nuclear energy is also applied in the production of wire and cables insulated with polyvinyl chloride degraded with gamma radiation. The use of radiation in these products leads to an increase in resistance to thermal and chemical aggressions.
Another important product is polyethylene foam degraded with radiations. Polyethylene foam is used in thermal insulation, impact padding, flotation vests and wood and plastic composites solidified with gamma radiation.
Last review: June 28, 2019