AP1000 can withstand the challenge

Sanmen and Haiyang Unit 1 has been inspected and evaluated by the National Nuclear Safety Administration and other functional departments for multiple rounds. The conclusions are from “materials and production preparations basically meet the requirements” to “with charging conditions”. However, some scholars in China have highly questioned the first time that the Sanmen and Haiyang nuclear power plants are “adventurous”.

 

The world's first three generations of nuclear power AP1000, the first reactor of Zhejiang Sanmen Nuclear Power Plant, and Unit 1 of Shandong Haiyang Nuclear Power Plant, which is also listed as the first batch of AP1000 self-reliant projects, have come after many delays. The most critical engineering node before the completion of the operation and commissioning - nuclear fuel loading, the unit with nuclear test operation.

 

Whole process supervision, phased license: conclusion of “with charging conditions”

 

"Basically effective, basically satisfied, and basically in line with" is a question that scholars question the repeated safety review before loading.

 

In this regard, Wang Bin, deputy general manager and chief engineer of the National Nuclear Engineering Corporation, pointed out that there is no “three basics” in the report of the scholars; there is only one relevant in the report, that is, “the charging and production preparation work is basically satisfied. Claim". This is because the report proposes 28 rectification requirements that need to be completed before loading, so the use of “basic” expression is scientific and rigorous. These rectification items were confirmed by the East China Nuclear and Radiation Safety Supervision Station on August 21 after verification.

 

The whole process of supervision and phased licensing is the basic feature of China's nuclear safety supervision. Lin Chengge, former deputy director of the National Nuclear Safety Administration, explained that the whole process of supervision is the whole process of “nuclear energy from an idea in the mind to reality”; the phased license is from the selection, design and construction of the nuclear power plant site. Every step of loading, running, and decommissioning must be reviewed and issued by the National Nuclear Security Administration.

 

The National Nuclear Safety Administration adhered to “zero tolerance” for false reports and violations of safety quality.

 

It is under such strict nuclear safety supervision that China's active nuclear power units have maintained good safety performance. So far, there have been no operational events at the International Nuclear Event Classification (INES) level 2 and above. Taking Sanmen as an example, since August 2008, Sanmen No. 1 nuclear island foundation pit was dug to the inspection tank until July 2017, the National Nuclear Safety Administration and East China Station conducted a total of 68 nuclear safety supervision and inspection. 442 nuclear safety management requirements, all requirements have been implemented.

 

“Basic Satisfaction” is a phased conclusion, emphasizing that only the completion of rectification can carry out the professional judgment of loading, ensuring full coverage of safety supervision and no leakage. Lin Chengge said that the nuclear safety supervision department found problems and made demands through supervision; the project construction party analyzed the reasons and implemented rectification. This process is iteratively repeated, and finally the project will ensure that the project fully meets the requirements of nuclear safety regulations, and the regulatory department will give the conclusion that the nuclear power plant has the charging conditions.

 

Main pump delay: the first pile of time and effort is not surprising

 

The Sanmen and Haiyang No. 1 units, which were scheduled to be put into operation in 2013, have been delayed for more than three years. They have been referred to as their core equipment such as shielded motor main pumps and blasting valves. They have never been used in pressurized water reactor nuclear power plants. Any empirical data support.

 

In this regard, Zheng Mingguang, dean of the Shanghai Nuclear Engineering Design and Research Institute and the chief architect of the National Science and Technology Major Project “large-scale advanced pressurized water reactor nuclear power plant”, said that it is the engineering technology industry to verify a new technology by trial and error of simulated actual working conditions. Common common sense. In the process of dealing with the problems of the main pump and the blasting valve, the technical personnel of China and the United States are adhering to this concept, repeatedly experimenting and demonstrating, and spent a lot of time, which is indeed the main cause of the project delay. However, by January 2016, the main pump and blasting valve problems had been fully resolved.

 

Taking the most critical shielding main pump as an example, the AP1000 main pump power is larger than the previous one, and the external size limit requirement is also higher, which brings more difficulty to the bearing design; but after 5 years of development and repeated debugging Verification, now 16 main pumps are operating normally and meet the requirements of the technical specifications. He revealed that the 50Hz CAP1400 main pump prototype independently designed and manufactured on this basis has passed the first stage test, indicating that the key four major indicators flow, lift, efficiency, and idle time (safety indicators) meet the requirements, and the durability test is being promoted. .

 

The development of new nuclear power technology will always encounter some unexpected problems, which need to be discovered and solved during the construction process, so often such projects will be delayed. For example, as the first reactor of the French three-generation nuclear power EPR, Finland's Orkilotto Unit 3 started construction in 2005, originally planned to start production in 2009, and now it is estimated that it will be delayed for 9 years.

 

Repeatable verification conclusion: recognized by three countries

 

At present, the AP1000 has passed the GDA security review of the US Nuclear Regulatory Commission (NRC), the National Nuclear Security Administration of China, and the UK Nuclear Safety Regulatory Authority, but has been questioned by scholars for its authority.

 

"This kind of recognition is by no means a fluke," Lin Chengge commented. Because it has been scientifically verified for 20 years, including numerous design verifications, checks, system bench tests for various operating conditions, and critical equipment bench tests... "The scientific nature of these test procedures is international engineering. Recognized by the technical community, the verification conclusion is repeatable." The first batch of AP1000 self-reliance projects rely on the “filling conditions”, which is also the scientific conclusion of the nuclear safety supervision authorities in accordance with the law. The AP1000's self-reliant support project is welcome to be questioned and even more questionable, Lin Chengge said.

 

It is also reported that on December 21st, US time, the Georgia Public Service Commission announced that it will continue to build Vogtle's two AP1000 nuclear power plants.

 

José Emeterio Gutiérrez, CEO and General Manager of Westinghouse Electric, said: "Today's decision is undoubtedly significant for the US energy industry and the global nuclear industry. The two nuclear power plants are reliable after being completed. Safe and clean energy will definitely have a positive impact on the Georgian economy."