Lead
In 2016, Continental's first miniature neutron source reactor underwent low-enrichment modification and achieved full power operation, which also attracted the attention of the International Atomic Energy Agency (IAEA), which recommended the development of microreactors and expressed its willingness to cooperate with Continental.
What kind of reactor is a miniature neutron source reactor?
How does it compare to a typical neutron source reactor?
The core is so small that it's the size of a pressure cooker, so what is it used for?
1. What is a miniature neutron source reactor?
A nuclear reactor is a special device used for nuclear fission, with a controlled release of energy.
In nuclear reactors, neutrons from fission of nuclear fuel cause the conversion of nuclides, which in turn produce more neutrons, forming a chain reaction.
The miniature neutron source reactor is a kind of reactor used to produce neutrons, the small size, small core, low power of the microreactor, because the microreactor has the characteristics of high safety, no special site and low cost, so it has been respected by many countries, and the International Atomic Energy Agency has also recommended and cooperated in the development of the microreactor.
There are many components inside a nuclear reactor, including the core, coolant circulation system, reaction control system, radiation protection system, and so on.
However, due to the low power and small size of the microreactor, the design can be greatly simplified, and the internal components are relatively few, mainly composed of the core, reflective layer, reaction control system and radiation protection system, so the cost is relatively low.
Since the microreactor is simple to operate, it does not require a special site and can be operated in the laboratory, so it is also very easy to use.
During operation, the microreactor does not produce residual heat from the fission of nuclear fuel, so no special measures are required for cooling.
However, a general nuclear reactor needs to use coolant to remove the residual heat generated by it and prevent the core from being damaged by the high temperature of the nuclear reactor.
There is also a reflective layer around the core, and the function of the reflective layer is to reflect neutrons back to the core to ensure a relatively uniform distribution of neutron energy and achieve stable operation of the reactor.
In addition, the radiation level generated by the microreactor during operation is very low, so it does not affect the surrounding environment and does not require special radiation protection measures, so it is very suitable for neutron activation analysis, isotope production, etc.
2. What are the uses of miniature neutron source reactors?
Microreactors are low in power, but they are suitable for many fields, and their main uses are two aspects, one is neutron activation analysis, and the other is isotope production.
Neutron activation analysis is a method that uses the interaction between neutrons and nuclides to analyze the neutron energy, and the neutron energy generated by the microreactor is relatively uniform, which can well meet the needs of neutron activation analysis.
Neutron activation analysis is a non-destructive analytical method that determines the types and contents of different nuclides in a sample by analyzing the number of activated nuclides produced by different nuclides in a sample and the decay characteristics of the activated nuclides.
Isotope production is another important use of microreactors, isotopes are a type of nucleus, and they have very important applications in chemistry, biology, etc.
Using the neutrons produced by the microreactor, it is possible to make unstable nuclides stable into stable nuclides, resulting in the preparation of isotopes that are not radioactive.
Isotopes have very important applications in diagnosis, treatment, and material preparation, such as isotope drugs in nuclear medicine to treat diseases, or for the preparation of nuclear pure substances.
3. What does a miniature neutron source reactor look like on the mainland?
What kind of reactor is a miniature neutron source reactor?
Can nuclear fuel from microreactors be smaller?
The nuclear fuel of the microreactor is highly enriched uranium-235, uranium-235 is an isotope of uranium, enriched uranium-235 can be used in micro neutron source reactors with a concentration of 3%, while the enrichment of general nuclear reactors is low-enriched uranium, and the enrichment degree is required to reach more than 3%.
The core height of a typical nuclear reactor is about 3 meters and the diameter is about 1 meter, while the core of a microreactor is as small as 24 centimeters in diameter and 27 centimeters in height, which is almost the same size as a general pressure cooker.
The small core of the microreactor can not only reduce the number of fission products produced during the operation of the reactor and reduce the radiation level of the core, but also better ensure the uniform distribution of neutrons in the core, making the operation of the microreactor more stable.
The small core of the microreactor also means that the structure of the microreactor is simple, the manufacturing cost is low, and the highly enriched uranium-235 in the core does not generate the residual heat generated by the operation of the nuclear reactor, so there is no need for cooling measures.
In addition, the small size of the core of the microreactor will also bring some inconveniences, such as the core of the microreactor does not store enough nuclear fuel, so the life of the core will be relatively short, and the nuclear fuel needs to be replaced, but due to the low cost of the microreactor, the replacement cost of nuclear fuel is not high.
In order to minimize the design difficulties, researchers in the mainland borrowed from the design of the microreactor in the United States, reduced the design size of the core to the minimum, and finally succeeded in developing the mainland's first miniature neutron source reactor.
epilogue
The success of the mainland's first miniature neutron source reactor marks the improvement of China's technical strength and safety level in the field of nuclear energy, and provides new opportunities for international cooperation and promotion.
The safety and sustainability of nuclear energy development is crucial to the global energy transition, and microreactors, as a form of high-safety nuclear reactors, are expected to become an important direction for future nuclear energy development.
China's leading position in the field of micro neutron source reactor technology demonstrates its foresight and strength in scientific and technological innovation and nuclear energy applications.
In addition to neutron activation analysis and isotope production, microreactors are also widely used in teaching, training and other fields, bringing new opportunities and possibilities to scientific research and education.
It is expected that China will make more achievements in the research of nuclear fusion technology, further promote the development of nuclear energy technology, and provide more clean and efficient energy options for mankind.