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Reactor shutdown is normally performed by insertion of control rods in the core. If this measure fails, in a socalled anticipated transient without scram (ATWS), a diversified system for reactor shutdown is required. Existing systems only ensure mid-term subcriticality of the core by injecting boron into the reactor pressure vessel (RPV) with common pumps.


Fast boron injection for diversified reactor shutdown in the case of an ATWS
A high-pressure nitrogen-driven tank filled with a boron solution is able to reduce the reactor power in less than two minutes. One tank of the Fast Acting Boron Injection System (FABIS) can inject the whole amount of boron needed to reach a subcritical state. The boron solution is directly injected into the bypass channels of the fuel assemblies. Hence, the fission chain reaction is stopped almost immediately. FABIS combines operating experience of a proven hydraulic scram system design with a new, fast way to reach subcriticality inside the core.


Your benefits

  • Fast boron injection process to directly reach subcriticality of the core
  • Fast diversified reactor shutdown to control an ATWS
  • After initiation no power supply for boron injection required
  • Required injection volume and time can be adjusted

Interested in Fast Acting Boron Injection System – FABIS?

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