Enhancement of On-line Corrosion Product Monitor for the trace amount of iron and copper in the feed water of a PWR

An On-line Corrosion Product Monitor (OCPM) has the capability to continuously measure the concentration of iron in the secondary feed water of PWR without pretreatment of the samples. However, the original OCPM also has some problems such as its uneasy handling and limited measured element. We have developed an enhanced OCPM that is capable of continuously measuring the concentration of iron and other trace elements in the secondary feed water of PWRs. The original OCPM design was used as the starting point, and the improved design features of the enhanced OCPM reduced the regulatory requirements for its use while improving the performance of the monitor. In all, many features and components of the system were considered in the optimization; including; the X-ray tube, the optical system, the detector, the geometry of the X-ray tube and detector, and the size of the system. A combination of a 50 wattage X-ray tube with a molybdenum target, a filtered excitation method, and a Si-PIN photodiode detector with Peltier cooling was chosen for the optimized design of this enhanced OCPM. The resulting design satisfies both the performance requirements and design features for the system. It is considered that the enhanced OCPM having the specification described above meets with the requirements concerning the performance properties and the monitor installation. (author)