Recently, news came out from the Southwest Institute of Physics of the Nuclear Industry of CNNC that the world's largest " artificial sun ", the first wall of the International Thermonuclear Fusion Experimental Reactor (ITER) with enhanced thermal load, has completed the first piece of manufacturing, and has met the conditions for mass manufacturing. The key components of this latest breakthrough, " first wall ", are actually the "firewall" of the "artificial sun", which can directly face the burning plasma of hundreds of millions of degrees Celsius.
With a distance of one meter, the temperature ranges from 100 million degrees Celsius to -269℃
"Artificial Sun", in short, is to build a device on the earth to simulate the sun's light, heat and release of energy, thereby solving the energy problems faced by mankind. "Artificial sun" generally refers to the International Thermonuclear Fusion Experimental Reactor Project.
The International Thermonuclear Experimental Reactor (ITER), which explores and develops fusion energy, is jointly built by seven parties: China, the European Union , India, Japan, South Korea, Russia, and the United States. It is known as the world's largest "artificial sun." Currently, ITER is progressing as planned in southern France and is expected to be completed in 2025.
Fusion energy has always been considered the ultimate energy dream of mankind. Just on November 22, 2022, news came out from the Southwest Institute of Physics of the Nuclear Industry of CNNC: The core component of the world's largest "artificial sun" - the International Thermonuclear Experimental Reactor (ITER) with enhanced thermal load, has completed the first piece of manufacturing, and has met the conditions for mass manufacturing.
This is my country's huge breakthrough in the field of controllable nuclear fusion . It marks China's comprehensive breakthrough in the key technology of "ITER Enhanced Thermal Load First Wall", achieving continued leadership in this core technology, and effectively enhancing my country's voice in this field.
ITER enhances the first wall of heat load, referred to as "first wall". It directly faces the high temperature of 100 million degrees Celsius in the vacuum wall plasma reactor core. It is the most critical core component of the ITER device and a key technology in the construction of nuclear fusion reactors.
Chen Jiming, chief expert in the field of engineering technology at the Southwest Institute of Physics of the China National Nuclear Corporation and head of the ITER enhanced thermal load first wall team, told reporters that the surface temperature of the sun is about 6,000 degrees Celsius, and 100 million degrees Celsius is equivalent to the cumulative burning temperature of 16,666 suns.
From the high-temperature plasma of 100 million degrees Celsius in the vacuum wall reactor core, it quickly drops to -269 degrees Celsius in the outer cladding, with only a gap of more than 1 meter in between. Currently, there is no material in the world that can withstand temperatures of hundreds of millions of degrees Celsius.
If you can't stand the high temperature, take the initiative to cool down. Cooling water cleverly solves the problem of material resistance to high temperatures, but the manufacturing, processing and installation of the "first wall" is also full of challenges.
The thermal load-enhancing finger part, referred to as "finger", is the most critical and core component in the "first wall", and it is not easy to make. The fit gap error between the copper and stainless steel connections in the component requires flashlight and can be seen from a backlit angle.
The special processing of the copper surface of the finger parts requires an error rate of less than 0.01 mm.
The finger part has three layers. The lower layer is stainless steel, the middle is copper, and the upper layer is metal beryllium. A supporting company in Ya'an, Sichuan, uses its own "unique skills" to closely fit these three metal materials with different characteristics.
Zhou Yi, assistant researcher at the Southwest Institute of Physics of China National Nuclear Corporation,
With the joint research and development efforts of more than a dozen supporting companies, the finger parts were processed and manufactured in March 2022. Since then, it has undergone 8 simulated high heat load tests, each lasting a week, and was successfully passed in October.
Just when Chen Jiming's scientific research team made important breakthroughs in finger components, his colleague Li Pengyuan's scientific research team also made new progress. Li Pengyuan's team is responsible for the research and development of the magnet support outside the first wall of ITER to enhance the thermal load, that is, the cladding outside the vacuum wall.
Li Pengyuan, researcher at the Southwest Institute of Physics of the Nuclear Industry of China National Nuclear Corporation
Similar to the processing and manufacturing of "fingers", the magnet support of the "first wall" is also inseparable from many supporting companies. Because it is a nuclear energy product, the processing requires zero tolerance and zero defects. Therefore, technicians must first use computer software to perform CNC program processing before actual processing.Even with the help of computers, this process is still difficult.
Using nuclear fusion to obtain a steady supply of clean energy like the sun has been a long-standing dream of mankind. On this road of research and development, it may be the loneliness of sitting on the "cold bench" of scientific research for 4, 5 years, or even longer, it may be the repetition of countless days and nights, or it may be the failure of testing again and again.
Every technology in the "artificial sun" needs to be tested repeatedly. The nearly stringent requirements have led to rapid iteration of relevant technology research and development and continuous application to civilian manufacturing. The high-temperature superconducting conductor recently developed by Li Pengyuan's team is one of them.
Not only that, but the processing supporting companies involved in the manufacturing of "artificial sun" components are also developing rapidly.
Cancer treatment is expected to use domestic nuclear technology
Cobalt 60, Carbon 14, and Yttrium 90 are three isotope raw materials. After they react with nuclear reactor , they become medical isotopes with radioactive . The isotope cobalt 60 is mainly used for gamma ray to treat tumor diseases. In 2009, my country has achieved the localization of cobalt 60.
isotope carbon 14 raw material is mainly used to detect Helicobacter pylori and is currently mainly imported. Yttrium-90 isotope raw material can be used for radioactive treatment of cancer. Currently, it basically relies on imports from abroad.
Internal radiation therapy using yttrium-90 isotope has been used internationally for more than 20 years, but it has only started to take off in my country in recent years. Zhejiang Cancer Hospital is one of the clinical research units of yttrium-90 radiotherapy in my country. This type of radiation therapy is suitable for some cancer patients whose tumors are large and are not suitable for surgery or chemotherapy.
However, Yttrium-90 is very expensive when used for radiotherapy. Behind this is the reality that my country has been unable to independently produce yttrium-90 isotope. Now, this situation is changing.
On October 28, 2022, my country’s largest isotope production base officially started construction in Haiyan, Zhejiang. It is expected to be completed and put into production in March 2025, which will effectively solve the problem of domestic isotope products being heavily dependent on imports.
The localization of yttrium-90 is inseparable from the efforts of Qinshan Nuclear Power . Taking the domestically produced yttrium-90 isotope raw material as an example, the first step is to develop and produce special glass microspheres.
Xu Zhongping, engineer of the R&D Department of Zhejiang Yihe Medical Technology Co., Ltd.
After the manufacturing of microspheres is completed, the production of pipelines is also indispensable. A supporting factory located in Wuxing District, Huzhou, Zhejiang, has built world-leading seamless pipe production lines and welded pipe production lines. The "target" pipes containing isotope raw materials are manufactured and processed here.
After the pipeline that meets the requirements is completed, the isotope raw material is loaded into it, and it becomes a "target". The "target" then enters the Qinshan Nuclear Power Plant nuclear reactor building.
The "target" containing isotope raw materials is placed in the nuclear reactor for two years. After fully absorbing the radioactivity of the neutrons produced by the fission of in the reactor, it is extracted from the nuclear reactor through remote operation with the help of a special shielded transport container, and is lifted to the "spent fuel pool" for cooling and radiation shielding.
In order to facilitate future transportation, the 3-meter-long, highly radioactive target was then dismantled into 20-centimeter sections and placed in a special container to await further processing.
Medical isotopes are the foundation and core of the development of nuclear medicine. At present, the research and development of localization of key medical isotope products is still in progress, which will bring hope to more cancer patients in the future.
column editor: Qin Hong Text editor: Song Hui Source of title picture: CCTV Picture editor: Da Xi
source: Author: CCTV Finance
