Analysis of criticality in shipment and storage of fuel at a nuclear power plant with a VVÉR reactor

The product of Fangjiashan Nuclear Power Plant (NPP) Unit1 Fuel Handling and Storage (PMC) System is the first Chinese PMC system, with its own intellectual property rights. During the development and design lifecycle for the product, China Nuclear Control System Engineering Co., Ltd (CNCS) was responsible for Verification and Validation (V&V) processes of the PMC system, taking a significant role for ensuring the reliability and safety of the software in PMC system. The PMC V&V project is also the first ever independent V&V project of the China nuclear industry. V&V is a technical discipline of systems engineering. The purpose of V&V is to help the development team build quality into the system during the life cycle. The V&V processes determine whether the product developed satisfies its intended use and user’s needs. V&V provides an objective assessment of products and processes throughout the life cycle. This assessment demonstrates whether the requirements are correct, complete, accurate, consistent, and testable. CNCS V&V PMC project team performed PMC V&V activities in compliance with IEEE Std 1012-1998, which is endorsed by NRC Regulatory Guide 1.168-2004. After critical analyses by V&V team, the Software Integrity Level (SIL) of PMC is SIL3, so associated V&V activities must conform to the minimum tasks list in IEEE Std 1012-1998 Table 1. After 2 years of hard working, Fangjiashan NPP Unit1 PMC system V&V activities have been completed. The whole activities and methodology was passed the final evaluation by the customer and was highly compliment by the international V&V expert committee at year of 2012. This paper discusses how to establish V&V organization and infrastructure, and then how to perform V&V activities in high quality, and the specific new and best practice methods, approach and tools for executing V&V tasks. Because the PMC V&V project is the first ever independent V&V project of the China nuclear industry, the methods, approach and tools which was executed in the whole lifecycle and depicted in this paper could help to guide and be referred by the future V&V activities and projects.

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Snesk — program for calculating first-loop coolant leaks into the boiler water of the steam generators of a nuclear power plant with a VVÉR reactor

Atomic Energy ◽

10.1007/bf02415549 ◽

1994 ◽

Vol 77 (6) ◽

pp. 944-945

Author(s):

E. A. Ivanov ◽

I. V. Pyrkov ◽

L. P. Kham'yanov

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Vver Reactor ◽

Steam Generators ◽

Boiler Water

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High-Level-Waste and Spent Fuel Storage in Switzerland

Volume 2: Mgmt. Low/Interm. Level Waste; Spent Fuel; Economics/Analyses for Waste Mgmt.; Radiological Characterization/Application Release Criteria; Panel Sessions; Solid Waste Reduction/Treatment; Current Activities in Central/Eastern Europe; Environmental Remediation Technology; LL/ILW; HLW/Spent Fuel; Chernobyl; D&D Waste; Performance Assessment; MOX and Spent UOX; D&D Nuclear Reactors; Decommissioning of Other Nuclear Facilities ◽

10.1115/icem2001-1173 ◽

2001 ◽

Author(s):

Udo Sach ◽

Goswin Schreck ◽

Max Ritter ◽

Jean-Pierre Wenger

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Radioactive Wastes ◽

High Level Waste ◽

Storage Facility ◽

High Level ◽

Interim Storage ◽

Fuel Elements ◽

And Storage

Abstract At present, Switzerland has no final repository for radioactive wastes. Very early, the Swiss nuclear power plant operators were aware of the necessity to expand interim storage capacity for spent fuel elements and operational wastes. Already in 1991, Nordostschweizerische Kraftwerke AG (NOK) therefore started building a reactor-site interim storage facility (ZWIBEZ) at its Beznau power plant site. Moreover, as early as in 1990, “ZWILAG Zwischenlager Würenlingen AG”, a company established by the nuclear power plant operators had initiated the licensing procedure for a central interim storage facility in Switzerland. This central interim storage facility is designed for the storage of all categories of radioactive wastes and includes a conditioning facility for low-level and medium-level waste. Eleven years later, in July 2001, the first transport and storage cask loaded with irradiated fuel elements was stored in this facility. For both of the stores the concept of dry interim storage in suitable storage casks in a storage hall was chosen for the storage of irradiated fuel elements and vitrified high-level wastes from reprocessing. Cooling is established through natural circulation. Leaktightness of the casks is continuously monitored by means of a cask monitoring system. The other wastes arising from nuclear power plant operation and reprocessing are stored in a ventilated storage hall which provides shielding and — depending on the radioactive inventory — protection against external impact. The conditioned radioactive wastes, packaged in drums, are placed into open storage containers with identical base and having the same sling points as ISO containers. These containers are stacked up in free-standing stacks up to a height of 16 m. The storage concept varies, depending on the radioactive inventory; for the ZWIBEZ reactor-site interim store, a storage hall for low-level waste has been built without partition walls, whereas the store for the medium and high-level waste in the central interim store ZWILAG has been designed with partition walls dividing the hall into several storage shafts which are closed by shielding slabs. By including a hot cell into the ZWILAG facility, the purpose of this facility has been expanded beyond interim storage of radioactive waste to cover also the visual inspection of fuel elements and vitrified waste canisters as well as the reloading of fuel elements and canisters from smaller transport casks into combined transport and storage casks. Furthermore, the hot cell enables inspection and/or repair work to be performed in the cask lid area of loaded transport and storage casks, the replacement of the lid seals of storage casks and the conditioning of medium-level waste.

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