Methods For Measuring Boric Acid Concentration: A review

Article Abstract: Boron due to its large neutron absorption cross-section is widely used in nuclear reactors to control reactivity; the reactivity control is accomplished in part by varying the concentration of boric acid dissolved in the coolant. In other words, it is vital to maintain the boric acid concentration uniformly distributed in the primary cycle. Otherwise, if the low-borated water is injected into the reactor core, it will result in a reactivity excursion. Non-uniform distribution of boron concentration in the reactor would result in reactivity accidents or difficulty of accurate implementation of an effective reactor control system which includes reactor core power threatening reactor safety operation.  During the past decades, many theoretical and experimental studies have been carried out paying more attention to boron dilution accidents in nuclear reactors. Periodic chemical sampling and boron meter prediction methods are the most common ways to measure boron concentration in the reactor coolant. Because it is difficult to measure boron concentration in the process of transient employing experiments, numerical simulation is adopted to study these phenomena. This paper summarizes the current research status of methods for measuring boron concentration and identifies the challenges. This paper would contribute to a better understanding of the different boric acid measuring techniques and provide future work guidance for researchers