Mercury Monitoring System
MMS

Automatic monitoring of mercury in air and other gases

Applications

Examples for different applications of the MMS:

Goldmine in Marathon, Canada

Cellroom in Newcastle, USA

Function

The sample is continuously drawn from each sampling point through special tubing to a heated multiplexer valve unit. One sample at a time is fed into the Mercury Vapor Monitor where the mercury concentration is measured. All sample lines are permanently purged with sample thus minimizing the response time of the system. This method allows for sample line lengths of 100 meters and more.

System design

The MMS system basically comprises a multiplexer-valve unit and the highly accurate and selective mercury detector VM-3000 Vapor Monitor. A bypass pump maintains a steady flow of sample through the sample filters, sample lines and multiplexer valves. Flow meters with optical alarm sensors guarantee that flow rates are stable. All components are installed inside a protective cabinet.

A special version employing the UT-3000 Mercury Ultratracer as detector is available for concentrations in the sub-µg/m³ range.

Options like air conditioning assure reliable function of the system even under extreme climatic conditions.

Data output

The analyzer unit can be connected to a PC with a serial cable or optionally with a fibre optic cable for operation under harsh industrial conditions.

Modbus or ethernet communication is available.

Stand-alone operation without PC connection is also possible.

Storage of measuring data

Measurement data are stored on hard disk as ASCII- and EXCEL files. Filed data can be retrieved at any time as graphic diagrams. A friendly search function enables the user to quickly find data of selected time intervals or data exceeding a threshold value.

Self diagnosis of the system and calibration

The MMS software permanently checks the status of the system. Low flow of bypass stream or sample, plugging up of sample filters and photometer malfunctions are detected by the system and an error message is displayed.

An optional calibration module allows automatic calibration checks and re-calibrations of the system. The calibration gas is generated by mercury vapor saturation of air and automatic dilution. The mercury filling of the calibrator is sufficient for the entire lifetime of the instrument.

Software and remote control of the analyzer system

The MMS-Win software allows remote control of the analyzer-multiplexer system via PC. It provides information to the operator such as: mercury concentrations for each sample point, history of measurement results for each sample point, status of the system and calibration information.

Alarm thresholds, duration of measurement for each channel, zero adjustment and specific deactivation of measuring points can be controlled by PC.

The operator can interrupt any running measurement and select a sample point for immediate measurement. It is also possible to deactivate any sample point. Emission reports are created automatically and stored as *.txt and *.xls (EXCEL) files.

Screenshots of software MMS-Win, clockwise from top to bottom:

Main window of MMS-Win with position of sampling points;
Time course of mean Hg-concentration channel 9;
Setting of alarm thresholds;
Measurement data displayed in EXCEL;