After 12 years of scientific research, the demonstration project of "Guohe No. 1"——
Promote the overall upgrading of the nuclear power industry and technology (Like these technological breakthroughs ③)
Gu Yekai Li Yunqi
"People's Daily" (17th edition on August 30, 2021)
On September 28, 2020, the landmark achievement of my country's third-generation nuclear power autonomy-"Guohe No. 1" was officially released.
This also means that my country has achieved a major breakthrough in the three-generation nuclear power autonomous strategy that has been implemented since the beginning of this century.
At present, the "Guohe No. 1" demonstration project is steadily advancing as planned, and the first phase of the project can realize combined heat and power, which will make greater contributions to a clean, low-carbon, beautiful China and energy transition.
"Guohe No. 1" is a large-scale advanced technology with independent intellectual property rights developed through major national scientific and technological projects of large-scale advanced pressurized water reactors and high-temperature gas-cooled reactor nuclear power plants based on the introduction, digestion and absorption of the third-generation passive pressurized water reactor nuclear power technology. PWR nuclear power model.
The design life of the unit is more than 60 years, and the safety level is 100 times higher than that of the second-generation nuclear power unit. The annual power generation of a single unit is about 12 billion kWh, which can meet the electricity demand of more than 22 million residents, and can reduce greenhouse gas emissions by more than 9 million tons.
The third-generation nuclear power technology has high safety, good economy, strong buildability, and convenient operation and maintenance. It is a veritable "national weapon".
The research and development work of "Guohe No. 1" was officially launched in 2008, and it took 12 years to complete.
As the lead unit, State Power Investment Group Co., Ltd. organized more than 600 units and more than 31,000 technical personnel across the country to participate, and accumulated more than 7611 intellectual property achievements, and established an internationally advanced third-generation nuclear power independent innovation system and industrial chain supply system , Marking that my country's nuclear power technology has achieved a leap from the "second generation" to the "third generation", and has advanced nuclear power autonomous, batch, and large-scale construction capabilities.
Zheng Mingguang, Chief Engineer of Nuclear Energy of the State Power Investment Group Co., Ltd., is the chief designer of a major national science and technology project for large-scale advanced pressurized water reactor nuclear power plants.
His understanding of the words "heavy and large" is very intuitive: "In a single unit of'Guohe No. 1', there are about 30 pieces of equipment and modules over 100 tons, and the largest module has a volume of more than 5000 cubic meters and a weight "More than 1,400 tons" "The containment is a "big capsule" with a diameter of more than 40 meters and a height of more than 70 meters. It is made of steel plate about 5 cm thick and can withstand a pressure of more than 40 tons per square meter. "There are 10,000 in the steam generator. Multiple U-shaped tubes for heat exchange, with a total length of more than 300 kilometers..."
"Guohe No. 1" successfully broke the monopoly of a number of materials and equipment manufacturing technologies, and all key equipment materials such as main pumps, blasting valves, pressure vessels, steam generators, and reactor internals have all achieved independent design and localized manufacturing.
Zheng Mingguang has a deep understanding of the four-character "independent innovation": "Standing at the high end of the world's nuclear power technology development,'Guohe No. 1'has filled a number of technological and technological gaps in my country's nuclear power industry and promoted the overall upgrading of the nuclear power industry and technology. It is a veritable'national weapon'."
Since the launch of the "July 28 Project" in 1970, my country's nuclear power industry has gone through a road of endeavour and innovation for more than 50 years.
"The first-generation nuclear power technology is mainly based on experimental research reactors. The main development stage of the second-generation nuclear power technology is from the early 1960s to before 1979. Nuclear power plants with countermeasures and response measures after nuclear power accidents are called second-generation nuclear power additions.” Zheng Mingguang said, “After the Three Mile Island nuclear accident in the United States, global awareness of nuclear power safety has further improved. Advanced nuclear power countries have focused on nuclear power design and operational safety. Full understanding, analysis and evaluation were carried out, and a series of measures to improve and enhance safety were put forward. The third generation of nuclear power technology came into being."
Zheng Mingguang introduced that as a third-generation nuclear power model "Guohe No. 1", the key nuclear safety design concept is "passive". For example, the containment cooling system adopts this concept and can operate without relying on external power sources.
"Using the steel shell as the heat transfer surface, the steam in the containment will condense on the inner surface of the containment under accident conditions, and then transfer the heat to the water film or the atmosphere outside the steel shell through heat conduction, and the inside and outside of the containment will be cooled. It's all a natural cycle."
"By placing the water of the safety system at a high level, once an accident occurs, the water will flow to the reactor core or containment surface under the action of gravity to automatically cool the reactor core, and at the same time, the containment shell is sprayed externally to form a cooling water film. , Reduce the pressure and temperature in the containment, and ensure that the safety barrier of the containment is not damaged." Zheng Mingguang said.
"Guohe No. 1" is a nuclear power model that comprehensively, systematically and completely implements the passive design concept, which has greatly simplified the system and equipment.
According to Zheng Mingguang, this "simplification" is not as simple as the principle seems, and requires a lot of theoretical analysis and systematic experimental verification.
Its safety equipment and corresponding spare parts have been greatly reduced, but safety has been greatly enhanced.
Factory prefabrication and modular construction shorten the construction period, and the convenience of operation and maintenance optimizes the economy, which can meet the development needs of my country's economic and social safety and efficiency.
The third-generation nuclear power independent technology research team has been working continuously, filling in one gap after another, and promoting the leap-forward development of nuclear power in my country
How to ensure that the third-generation nuclear power has stronger competitiveness on the basis of high safety?
How to develop a competitive nuclear power plant and realize mass construction?
In Zheng Mingguang's view, these must be resolved through independent localization.
With these challenges, the Chinese nuclear power people have officially embarked on the innovative road of independent localization of the third generation of nuclear power.
The first thing before us is a seemingly insurmountable obstacle. According to the cooperation agreement with foreign parties, only if the electric power exceeds 1.35 million kilowatts, my country can have the independent intellectual property rights of the third generation of passive nuclear power.
To this end, the third-generation nuclear power independent technology research team represented by Zheng Mingguang has re-innovated the top-level design of "Guohe No. 1" on the basis of the original technical plan, including increasing the diameter and diameter of the steel containment vessel. Thickness to expand the space of the nuclear island, redesign and develop the reactor coolant pump, steam generator, blasting valve and steam turbine generator, greatly optimize the main pump flow, the main pipeline flow section, etc., to achieve the overall safety, economy and efficiency of the model The overall improvement.
"1.35 million kilowatts is a'gateway' for passive safety and main equipment." Zheng Mingguang said, "In order to ensure that we have independent intellectual property rights, we have decisively adjusted the plan. This is not a simple scaling up, we must truly understand Design, understand technology, have the ability to independently develop and test independently, without mastering the core technology, this'threshold' will not pass."
In order to increase the power of nuclear power models, from material research and development to component production to equipment installation and commissioning, it is almost necessary to re-validate, analyze, evaluate and develop.
The primary circuit coolant pipeline, referred to as the "main pipeline", is a large pipeline that connects the main equipment such as the pressure vessel and evaporator of a nuclear power plant, just like the "aorta" of the human body.
In order to be safer and more reliable, the main pipeline of "Guohe No. 1" is designed as an integrated forging without welds.
After the main pipe is thermally processed, it needs to be bent. Any improper control will lead to failure, and it can only be constantly explored and improved by experiment.
In more than two years, a number of participating units have coordinated research and tested the main pipeline blanks from 8 tons, 20 tons, 36 tons, and finally upgraded to 70 tons. In the end, the "large artery" forged in China was successfully developed.
The reactor coolant pump, referred to as the "main pump", undertakes the important task of providing power for the operation of the nuclear island, and can be regarded as the "heart" of the nuclear power plant during normal power operation.
The new manufacturing process and operation process are a huge challenge for the manufacturing industry.
In order to eliminate the probability of coolant leakage in the event of a power failure in the whole plant, it was decided to adopt a new type of main pump without shaft seal. The "two-wire parallel" mode was adopted at the beginning of the model development. plan.
After ten years of hard work, the wet winding main pump and the canned motor main pump have been successfully developed, effectively supporting the landing of advanced nuclear power models.
From nuclear power "aorta" to "heart", from "brain" nuclear design and safety analysis software, to "central system" nuclear power instrumentation, to a meter and other "blood vessels" and "nerves" all over the nuclear island...From From design plan to product development, the third-generation nuclear power independent technology research team has been working continuously, filling in one blank after another, gnawing one piece after another "hard bones", and working hard on the key core technology "neck" to promote my country's nuclear power has achieved leapfrog development.
The successful development of "Guohe No. 1" is inseparable from the effective organization and management of major scientific and technological projects
The successful development of "Guohe No. 1" is inseparable from the effective organization and management of major national science and technology projects: the reactor pressure vessel was jointly developed by Shanghai Nuclear Engineering Institute and China First Heavy; the steam generator was jointly developed by Shanghai Nuclear Engineering Institute and Dongfang Electric (Guangzhou). ) Jointly developed by Heavy Machinery Co., Ltd. and Shanghai Electric Nuclear Power Equipment Co., Ltd.; the main pump research and development "two-line parallel", the participating units have a clear division of labor; the main pipeline manufacturing is difficult, and the backbone enterprises in the machinery industry form a consortium to gather intelligence; U The material process problems of pipes, nuclear-grade zirconium materials, nuclear-grade welding materials, large forgings, etc., are finally solved successfully by the method of collaborative advancement of industry, university and research...
"Using the major national science and technology projects, the technology development of each equipment and material is deployed with 2 to 5 competitive and enthusiastic units to participate in the development. We have iterated many times from design technology to manufacturing technology and process, and introduced a competitive mechanism. , Use market-oriented means to promote the corresponding technological competition and stimulate the vitality of innovation.” Zheng Mingguang introduced, “Guohe No. 1”, a large number of relevant universities, research institutes, and enterprises in the United Nations, have jointly built three generations. The nuclear power independent technology research team has comprehensively deployed scientific research tasks and project implementation, effectively giving play to the advantages of the new nationwide system.
Independent design and manufacturing can not only enhance the economics of nuclear power plants, but also provide reliable and sustainable resource guarantees.
At present, a relatively complete supporting capacity and supply system for complete advanced nuclear power equipment has been formed in China, as well as standardized, batch-oriented, and industrialized production capacity.
my country has the equipment capacity to produce 8-12 units/sets of advanced nuclear power units annually.
Through the autonomy of three generations of nuclear power, my country is now catching up with the highest level in the world.
Zheng Mingguang proudly said: "With guaranteed technology, advantages in safety, and economic competitiveness,'Guohe No. 1'will effectively support the construction of a new power system with new energy as the main body, and help'carbon peak, Achievement of the'carbon neutrality' goal."