The CMM employs cold vapour atomic fluorescence (CVAF) to produce low detection limits. The company says it costs less than other comparable mercury monitoring instruments and has low operational costs because it doesn’t require separate chemicals, amalgamation concentrators, air scrubbers or additional gases.
Gasmet has installed systems in Finland and Poland and says the initial CMM’s have measured low mercury levels without cross-interference from gases such as sulfur dioxide.
The CVAF spectrometer has an integrated high temperature converter to transform mercury compounds to atomic mercury without any chemicals or vulnerable catalyst materials. The close coupling of converter and fluorescence cell also ensures that mercury does not recombine to, for example, mercury chloride between the converter and the mercury analyser, the company says.
According to Gasmet, sample gas dilution with synthetic nitrogen generated within the CMM system is an effective tool to promote sample transportation while decreasing the loss of Hg0 fluorescence signal to interactions with O2, CO2, and H2O.
The company says the fluorescence cell is 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 by the Mercury and Air Toxics Standards for new power plants, finalized by the EPA last month.
The system is controlled through a touch screen control panel, which is integrated with the analyser and calibrator inside an air-conditioned cabinet. 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. It can also perform periodic linearity checks with atomic mercury or mercury chloride.
Gasmet says it has received inquiries from companies preparing for legislation to limit mercury emissions from combustion processes, as well as processes managers from sulfuric acid manufacturing plants that want to control mercury in end-product by measuring directly in the process stream.