A THERMOSTABLE HIGH PRESSURE XENON GAMMA-RAY DETECTOR FOR MONITORING CONCENTRATION OF KCL DURING FERTILIZER MANUFACTURING

Abstract The abundance of 40 K isotope in natural K is about 10 −4 . Therefore, measurements of the intensity of the 1.46 MeV gamma line from 40 K allows to estimate the concentration of KCl in various mixtures and solutions. However, during the technological procedure it is necessary to carry out the measurements at a relatively high temperature, typically at about 120°C, where traditional detectors cannot be used. A high pressure xenon gamma-detector has been developed for these kinds of measurements. The detector is a cylindrical ionization chamber with a sensitive volume of 5 l. The pressure of xenon gas inside the chamber is 40 atm. A special charge sensitive amplifier capable to operate at high temperatures up to 200°C was designed for these measurements. The detector test under real industrial conditions at “Silvinit” – a company located in the North East of European part of Russia – proved that the concentration of KCl can be measured directly during the manufacturing process with an accuracy better than 1% in the temperature between 15°C and 120°C.