Nitrogen in PWR: Role & Equilibrium Activity

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Nitrogen plays a crucial role in pressurized water reactors (PWR) through the production of N-16, which serves as an indicator of reactor power levels. N-16, generated from an n,p reaction with O-16, reaches equilibrium activity in approximately one minute due to its short half-life of 7.16 seconds. Its activity is influenced by the fast neutron flux, which correlates with the fission rate and overall power output. In contrast to boiling water reactors (BWR), which utilize hydrogen water chemistry, PWRs maintain a slightly reducing water chemistry to minimize crud transport while keeping pH levels between 6.9 and 7.4. Understanding the behavior of N-16 is essential for effective monitoring and safety in PWR operations.
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Can anyone help me to understand the function of nitrogen in PWR.

What I know about unstable N-16 is that it is used as an indication of power PWR. How fast does it achieve an equilibrium activity?

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The half-life of N-16 (which is produced by an n,p reaction of O-16) is 7.16 s, so equilibrium is achieved rapidly - in about 1 minute. But then it also decays quite rapidly, so a detector must be close to the core. It's activity would be a function of the fast flux, which itself is related to the rate of fission or power.

N-16 is a matter for BWRs, which use hydrogen (reducing) water chemistry, since N-16 is carried through the main steam line to the turbine. PWRs use a slightly reducing water chemistry to prevent crud transport, although the pH these days tends to be 6.9 - 7.4 depending on the plant.

Reference:
http://www.nndc.bnl.gov/chart/reCenter.jsp?z=7&n=9 (then use zoom 1 in upper right corner)
 
Thnx 4 yo speedy & what I find as an accurate answer to the question. Many more thanks for providing the link. Cheers!
 
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