NGA 2000 Heated NO/NOx Analyzer Module Wet Chemiluminescence Detection

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Heated sample handling module for hot/ wet gas samples Eliminates loss of NO2 in sample condensate Built-in Peltier cooler removes moisture after NO2 conversion Thermoelectrically cooled solid state detector ensures high stability Automated ozonator shut-off on loss of air pressure Remote control and automatic calibration capabilities On-line diagnostics Efficient, interferent-free vitreous carbon NO2 converter

FEATURES Emerson's Rosemount Analytical NGA 2000 Wet Chemiluminescence Detection Analyzer Module (WCLD) is the industry's first modular analyzer designed to meet stringent environmental regulations on NOx emissions. The loss of NO2 due to solubility in sample condensate typically encountered in standard sample handling systems has been eliminated. The WCLD's heated sample conversion module is designed to accept a hot/ wet gas sample directly from the source. External sample handling requirements are therefore minimized. The WCLD is an extremely versatile instrument due to the heated sample conversion module. Applications such as internal combustion engine emissions (ICEE), continuous emissions monitoring systems (CEMS) and NOx scrubber efficiency monitoring among others can all benefit from increased accuracy and simplified sample handling requirements associated with the WCLD. The NGA 2000 WCLD Analyzer Module is a selfcontained unit complete with sample conversion, detection and associated electronics. The modular design allows for easy system integration, expandability and flexibility. The WCLD Module may be a "stand alone" instrument with the addition of our Input/Output (I/O) Module and Platform or it can be integrated into a sophisticated multicomponent analysis network. What makes the NGA 2000 Analyzer family unique is the modular approach combined with an advanced digital communication network (LON). The network allows identification of and interaction with other analyzer modules in the analytical system. All pertinent analyzer outputs and diagnostic information is carried on the network to a centralized display panel on the platform or to a remote PC. Because of this distinctive feature, the WCLD Analyzer Module may either be incorporated into a panel/rack or it can be placed near the sample source up to a mile away, thereby further reducing sample handling requirements. The WCLD analyzer module is designed to meet stringent U.S. Environmental Protection Agency requirements for NOx monitoring. Increased accuracy is achieved over conventional NOx analyzers by converting water soluble NO2 to NO in a heated sample conversion module. This hot NO2 to NO conversion eliminates the loss of NO2 in sample condensate. Moisture is then removed from the sample gas before analysis in order to eliminate water interference with the chemiluminescence reaction. The WCLD analysis system consists of three separate but interconnected modules: Sample Conversion Module – accepts hot/wet sample gas and converts NO2 to NO in a heated oven compartment. The vitreous carbon NO2 converter provides high conversion efficiency and minimizes interferent effects. The oven also contains sample handling components to control sample pressure, bypass flowrate and NO/ NOx mode switching. A thermoelectric cooler then removes condensibles from the sample gas. Chemiluminescence Detection Module – measures concentration of NO in the conditioned sample gas. The module houses the chemiluminescence reaction chamber, thermoelectrically cooled detector, ozone generator and associated electronics. Platform – performs control unit functions with operator interface. Analog/digital outputs, alarm contacts and digital inputs are available on the Input/Output (I/O) module located inside the platform. One platform can interface with several other NGA analyzer modules like CO, O2 and hydrocarbons, thereby significantly reducing installation and operating expenses. Many new refinements have been added to the WCLD to enhance overall performance. A new solid state (silicon photodiode) detector provides unsurpassed stability and low maintenance. A two-stage Peltier cooler maintains thermal stability inside the detector assembly to minimize signal to noise ratio. An internal ozone generator supplies the steady source of ozone required for the chemilu- minescence reaction. A pressure switch automatically turns the ozonator off in the event of loss of air pressure to prevent the possibility of corrosion. A back pressure regulator ensures steady sample pressure in the reaction chamber resulting in an ideal chemiluminescence reaction. The WCLD analyzer is equipped with four user-selectable ranges and auto ranging capability. The analyzer can also be equipped with an auto calibration cycle. The digital communication network (LON) allows diagnostics to be monitored while analyzers are in service to anticipate service requirements and minimize downtime. Information like detector temperature, duty cycle, peakpeak noise, converter temperature and power supply voltages, are carried on the network between the analyzers and a remote platform or PC. In addition to complete analyzer operation on the network, I/Os are available in the platform providing analog outputs and external control of analyzer functions. APPLICATIONS The NGA 2000 WCLD analyzer can be used for a variety of applications. Typical applications include: NO/NOx emissions from combustion of fossil fuels in: Vehicle engine exhaust (Meets EPA regulations for heavy duty gasoline and diesel engine testing per 40CFR, Part 86) Incinerators Boilers Gas appliances Turbine exhaust Nitric acid plant emissions Selective catalytic reduction (SCR) process control and efficiency monitoring NO emissions from landfill decomposition