The KK650 is designed specifically for measuring hydrogen and chlorine gases within the chlor-alkali industry. Hydrogen measurement is our field of expertise, but this application is not straightforward. Hydrogen levels are low and the mixture is not binary. In addition to the hydrogen and chlorine; oxygen, nitrogen and carbon dioxide are also present. These are referred to as the ‘inerts’. At start-up, the gas stream mainly consists of nitrogen purge gas with a gradually increasing percentage of chlorine.

All types of chlorine plant can be monitored by one of two models which differ in the hydrogen range and resolution (see specification). Each provides accurate monitoring of the process gas from start up to normal running.

 

The KK650 uses two measurement sensors together with a third, sealed reference sensor. The process gas is passed across the first measurement sensor, then through a small heater where hydrogen is reacted and then across the second measurement sensor, which measures the thermal conductivity of the reacted mix. The unique design of our software algorithm and dual sensor katharometer, allows the analyser to interpret and calculate the hydrogen, chlorine and inert gas components of the chlor-alkali process gas and ouput both hydrogen and chlorine values.

 

Calibration of chlorine analysers normally requires the handling of hazardous gases by highly trained personnel. The KK650 can be calibrated using the standard chlorine and chlorine/hydrogen mixtures but it also offers alternative calibration methods, which overcome the problem of handling hazardous gases.

The KK650 offers the advantage of being able to be calibrated using benign or surrogate gases; Argon for chlorine span and Hydrogen in air for hydrogen span. These gases are non-hazardous and can be readily obtained, thus simplifying the calibration process.

Alternatively, the KK650 can be calibrated using the process gas; assuming that the composition of the process gas is known and that there is confidence in analysis of the process gas as provided by other analysers (e.g. gas chromatographs).