Continuous Mercury Monitor is Sensitive and Simple to Run for Gas Detection

As regulatory pressure to monitor mercury emissions increases, Gasmet has developed a new type of continuous monitoring system for Gas Detection that offers process operators the chance to demonstrate compliance whilst finding new ways to improve their processes. Employing cold vapour atomic fluorescence (CVAF), the fully automatic Gasmet Continuous Mercury Monitor (CMM) has been designed to be simple to operate with a low maintenance requirement. However, the major advantages of the CMM are the very low detection limits that it offers in combination with the highest levels of reliability.

The CVAF spectrometer has an integrated high temperature converter to effectively transform mercury compounds to atomic mercury without any chemicals or vulnerable catalyst materials. Sample gas dilution with synthetic nitrogen generated within the CMM system is an effective tool to promote sample transportation whilst decreasing the loss of Hg0 fluorescence signal to interactions with O2, CO2, and H2O. The fluorescence cell is specially designed to eliminate stray reflections and background light so that even with sample dilution the CMM system is capable of monitoring low levels of mercury as required in the forthcoming US Clean Air Mercury Rule.

The system is controlled through a touch screen control panel, which is integrated with the analyser and calibrator inside an air-conditioned cabinet and calibration is maintained with regular automatic zero and span calibrations using Hg0 and HgCl2 calibration gases generated within the CMM system - typically every
24 hours. Periodic linearity checks with atomic mercury or mercury chloride are also possible.

Initial users of the Gasmet CMM have reported excellent reliability with low maintenance requirements and since no separate chemicals, gold amalgamation concentrators, air scrubbers or additional gases are required, operational costs have been minimal.