In Xataka we talked about many things great challenges Faced with researchers working in the field nuclear fusion to the possibility of advent the first commercial fusion plant. However, there are other challenges which, because they seem less relevant, are often hidden. One of them simply consists of the need to reduce the amount of impurities and ash present in the vacuum chamber of the reactor and to develop the necessary technologies to transfer them outside.
The ash and pollution originate from the nuclear fusion of deuterium and tritium, the two isotopes of hydrogen involved in the reaction, as well as the interaction of the continental plasma with the darkest layer of the mantle. This last element covers the interior vacuum bed reactor and has a critical role. It is at the forefront because it has been exposed to the direct impact of high-energy neutrons resulting from the fusion of deuterium and tritium nuclei.
Boron is an essential ingredient in experimental nuclear fusion reactors
Before moving on, it is worth briefly investigating an element of fusion reactor energy called a “diverter”. The vacuum chamber forms the base of the reactor and, if we stick to it THE JOURNEY (International Thermonuclear Experimental Reactor) the experimental fusion reactor being built in the French town of Cadarache is made up of 54 identical pieces of stainless steel. Of course, they all incorporate tungsten targets, which are responsible for sustaining neutron energy bombardments from the plasma, converting their kinetic energy into heat. The water that circulates inside is responsible for dissolving this thermal energy and cooling the “diverter”.
Moreover, there is an urgent reason why it was worth dedicating a few lines to this part: one of its tasks is to clean and carry out the plasma. they cast out ashes and filth which significantly reduce the fusion reaction. But he can do something greater. It is possible to take a preventive plan, which allows to reduce the amount of impurities coming from the carpet of the empty room. This idea is precisely what invites us to pay attention to boron.
Boron is a semimetal, so it has some of the properties of metals and others of non-metals.
This chemical element is a semiconductor, which means that depending on the pressure, temperature, radiation or other conditions to which we expose it, it behaves as a conductor of electric current or as an insulator. Moreover, it is a semi-metal, so that it has some of the properties of metals and some of non-metals.
Boron is relatively scarce in the Earth’s crust. We can find it in rocks as borax or colemanite, which is naturally formed due to the evaporation of water rich in salts from some lakes located at high altitudes and in desert areas. We can also find out dissolved in sea water from the precipitation of boron particles suspended in the atmosphere, as well as the erosion of the rocks containing them, and its circulation through the hydrological cycle, which explains how boron is transferred to the oceans through runoff dissolved in water.
In the field of nuclear fusion, boron plays an absolute role. Its physicochemical properties allow it to be used as a thin layer of this semimetal on the surface of the vacuum chamber of elements directly exposed to the plasma in order to significantly reduce the impurity and complete the growth reaction. The process of depositing boron inside the reactor is known as “boronization”. At the moment This technique is proven in experiments hosted in Switzerland, France and Germany with excellent results. In fact, boron will certainly be present in both ITER and other fusion energy reactors.
Image | Jan Michael Hosan / Max Planck Institute for Plasma Physics
More information | Eurofusion
In Xataka | Japan takes the lead with nuclear fusion and sets a very ambitious date: the 2030s
