This report is the first volume out of two focusing on BWR chemistry. A review and discussion of the BWR chemistry fundamentals that are necessary to understand and describe the requirements of the BWR water specifications is provided in this volume. This discussion includes the basics of water radiolysis, the dynamic process that establishes the concentration of oxygen and hydrogen gas in the reactor water, the consequences of tramp uranium and leaking fuel rods on chemistry and other relevant topics.
This report is the second volume out of two focusing on BWR chemistry. This volume II takes a closer look at corrosion of structural materials covering the following topics:
- Corrosion Considerations
- Stress Corrosion Cracking Mitigation
- Start-up IGSCC Mitigation
- Shutdown Dose Rate Minimization
- Reactor Water Purity Transients
- Surveillance Programs
This Report gives a comprehensive understanding of the zinc chemistry mechanism and information on how Zinc Chemistry in BWR and PWR plants was introduced in the plants and explains the results achieved. This information is useful not only for utilities that are intending to apply Zinc Chemistry in the near future in their plants and for selecting strategies for adding zinc; but also for those utilities that are already applying Zinc Chemistry in order to optimize their strategy based on international experience. It will also be useful for Manufacturers and Regulators.
The objective of this report is to provide members with the basic understanding of the mechanisms involved and their relationship to material performance and activity buildup. Content of the report is outlined below.
- Fuel cladding failures due to accelerated corrosion
- Axial Offset Anomaly (AOA)
- Pressure drop problems especially in CANDU-plants and VVER units
- Build-up of out-of-core radiation fields
- Shutdown extensions due to high activity releases (Coolant clean-up)
- Increased generation of radioactive waste
- Interference with inspection necessities
Operational Issues, Practices and Remedies are important issues for plant personnel and designers. This report combines the following subjects of limited extent but potentially important consequences:
- Degradation of the primary coolant barrier together with mechanical remedies.
- The potential benefits of Enriched Boric Acid (EBA).
- Primary coolant (Co-58, colloids) inventory.
- Degradation of concrete structures in NPPs.
- Colloids, Zeta Potential and Activity Transport.
- Electrochemical Corrosion Potential (ECP) measurements.
- Key points, ”lessons learned” and ”best practices” of several recent conferences.
The intent of this Report is to provide a state-of-the-art knowledge of the mechanisms of the various forms of Zr-alloy corrosion and hydrogen pickup (HPU) and how water chemistry impacts fuel performance, including corrosion and HPU. This knowledge will help implement actions to reduce Zr alloy corrosion and hydrogen pickup.
This Report furnished in the LCC10 Programme cover the key information presented at the Nuclear Power Chemistry Conference, in October 2014. The Report not only summarise but also analyse the results to assess in which specific situation the results are applicable.
The objective of this Report is to provide a comprehensive understanding of radiochemistry in Nuclear Power Plants which has a large impact on dose rates, operational exposures, maintenance activities, shutdown process, safety issues, environmental constraints and control of proper plant operation.
The objective of this Report is to help the reader to gain a basic understanding of the mechanisms involved in the Decontamination and the Steam Generator Chemical Cleaning Processes. The processes described do not only deal with the basic description but also with application considerations. A second approach to Decontamination is a chronology of the plant applications which range from components to subsystem and full system Decontamination.
This report is the first volume out of two focusing on PWR/VVER chemistry. This document is intended to provide a detailed description of the PWR/VVER Primary Side Coolant Chemistry. Furthermore, it should provide a strong support to the utilities for establishing a responsive plant specific chemistry program. It may also help the Manufacturers and Regulators at having a detailed approach of primary water chemistry and corresponding issues.