Nuclear Power Reactor Safety Requirements
Source: China Energy News Date: 2016-01-22
With the development of domestic small reactor design and development, the establishment of corresponding safety requirements has also accelerated.
The General Office of the Ministry of Environmental Protection has recently issued the "Principles for the Safety Review of Small Pressurized Water Reactor Nuclear Power Plants" (trial) compiled by the National Nuclear Safety Administration in order to standardize the safe development of small pressurized water reactor nuclear power plants in China while ensuring safety To guide the safety review of small pressurized water reactor nuclear power plants.
It is understood that due to the current research status and the requirements of nuclear safety review, the safety objectives, defense in depth, design basis, external event protection, accident source items, and emergency response of small pressurized water reactor nuclear power plants proposed in the Review Principles The plan, probabilistic safety analysis and application descriptions are only applicable to demonstration projects where the thermal power of a single stack is less than several hundred megawatts and the number of units at a single site is small. Some problems caused by the existence of a large number of modular units at a certain site are not involved for the time being.
Higher security goals
Plutonium technology is safe, reliable, and versatile. Small reactors are favored for various advantages. Authoritative forecasts have stated that by 2030, there will be 18.2 million kilowatts of modular small reactors in operation worldwide. By 2050, modular small reactors can account for 25% of the installed nuclear power capacity in OECD and non-OECD countries, and small reactors will gradually form a "climate."
Information shows that Russia, the United States, South Korea, and Japan have developed a number of design schemes to replace old coal-fired and oil-fired power plants, as well as power generation, residential heating, and industrial steam supply. For example, Russia has five different small reactor prototype reactors under development, and the US government has invested heavily to support a five-year small reactor research and development program. B & W, Westinghouse, and other US companies have proposed various types of small reactors.
The Chinese nuclear energy community also recognizes the importance of small reactors. Related companies have accelerated their deployment in recent years, and some have selected plant sites. Moreover, the modular small-scale reactor demonstration project was included in the national "Twelfth Five-Year Plan" for energy development and the "12th Five-Year Plan" for national energy technology.
"The domestic R & D of small reactors is in line with the world, and the corresponding safety standards, safety reviews, and safety supervision must be accelerated and improved." An industry expert told reporters.
It is understood that internationally, a relatively complete set of nuclear safety requirements has been established for traditional large-scale pressurized water reactor nuclear power plants. Some important safety principles are applicable to small-scale pressurized water reactor nuclear power plants. However, due to the characteristics of the small-scale pressurized water reactor nuclear power plant itself, the “determination method” deterministic safety requirements that are closely related to the reactor type and system design established for traditional large-scale pressurized water reactor nuclear power plants are not completely suitable for small reactors. In this regard, the international nuclear energy community has reached a consensus and has begun to try to establish a set of safety requirements applicable to small nuclear power plants.
As China's nuclear safety regulatory authority, the National Nuclear Safety Administration also recognizes the above issues.
The “Evaluation Principles” clearly states that “According to the needs of the safety review, this review principle is formulated for small onshore pressurized water reactor nuclear power plants that are used for power generation, heating, steam supply, etc., and whose site may be close to users. To clarify positions on some important safety issues. At the same time, the formulation of this review principle and future practice in the safety review of small pressurized water reactor nuclear power plants will also explore experience for the formulation of relevant nuclear safety regulations and standards in the future. . "
The reporter noted that the pilot version of the Review Principles set higher safety targets for small nuclear power reactors.
"Establish and maintain effective defenses against radiological hazards in small pressurized water reactor nuclear power plants to protect personnel, society and the environment from harm." The Review Principles state the overall nuclear safety goals of small pressurized water reactor nuclear power plants. . In the technical objectives, in particular, "the possibility of ensuring the substantial elimination of the release of a large amount of radioactive material" and "small pressurized water reactor nuclear power plants should provide the public with PWR nuclear power plants take off-site interventions to a higher level of protection. "
Continuous practice and awareness
Safety review is a key link for a nuclear power project from R & D design to engineering application. Passing the safety review is like getting a “safety pass” for the project, and other preparations before approval for construction can be smoothly advanced.
In April 2007, the National Nuclear Safety Administration has issued the Principles of Nuclear Safety Review for Second Generation Improved Nuclear Power Projects. In May 2008, the Nuclear Safety Administration sent a letter to solicit opinions on the Principles for Safety Review of High-Temperature Gas-Cooled Reactor Nuclear Power Plants. For small reactors that have no engineering applications in China, the formulation of the “Review Principles” refers to the latest results of research on safety requirements for small pressurized water reactor nuclear power plants at home and abroad.
At present, China Nuclear Group has developed a multi-purpose modular small reactor (ACP100 series) with independent intellectual property rights. According to different application scopes, it is divided into two types: onshore small reactors and offshore floating reactors. CGNPC has developed the compact small reactor ACPR50S and integrated onshore small reactor ACPR100 for offshore nuclear power plants. In recent years, National Nuclear Power has extended the passive series to the design of small reactors and is building CAP150. In addition, a high-temperature gas-cooled reactor demonstration project jointly launched by Tsinghua University, Huaneng Group and China Nuclear Construction Group has started.
How to apply the Review Principles for different designs and different products?
"It should be fully recognized that the establishment of safety requirements for small pressurized water reactor nuclear power plants must go through an iterative process of practice, awareness, re-practice, and re-understanding. The application of this review principle should also hold such an attitude." The Review Principles clearly state.
"The trial version of the" Evaluation Principles "is to a large extent a path exploration. In the future, it will continue to be adjusted in accordance with specific practices to guide and standardize the development of small nuclear power reactors." The aforementioned industry experts told reporters.
The National Nuclear Safety Administration also pointed out that in the design process of small pressurized water reactor nuclear power plants, all units should take into account the technical characteristics of small pressurized water reactor nuclear power plants, analyze accident methods, accident radioactive source terms and release mechanisms, operation management, Further research on emergency strategies. If problems are found during the application of the review principles, they should be reported to the National Nuclear Safety Administration in a timely manner.