Laser monitoring system 4750-PM

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The 4750-PM is a laser analyser that uses a back-scattering technique to provide accurate, reliable measurements of particulate matter in stacks and ducts, for processes where condensed water is not present. With a rugged design suitable for a wide range of applications, it features a highly stable optical system, with large-area collection, offering a low detection limit of less than 1 mg/m3. Operating in a wide temperatures range, the 4750-PM uses a stack-mounted sensor with combined internal user interface, and has no moving parts, since the optical path is pre-set to maximise measurement across the stack. Suitable for use as a continuous emission monitor (PM-CEMS) for compliance or process monitoring, the 4750-PM is idea for applications in the power generation, glass, industrial boilers, metals refining, minerals and pulp & paper industries. Minimum duct size is 1.5 m (59 inches). WIDE TEMPERATURE RANGE Employing a non-intrusive, laser back-scattering sensor, the 4750-PM does not require any delicate components to be placed in the stack, so it can be used in temperatures up to 250°C (400°F). CALIBRATION AUDIT AND CHECK Filter audit units allow for periodic linearity checks to ensure compliance with international and national emission monitoring standards. Zero and upscale calibration can be checked by inserting pre-defined filters to suit compliance requirements. BACK SCATTER TECHNIQUE As particles travel through the laser beam, they scatter light in all directions. Back-scattered light is collected on a detector, with the instrument design ensuring that stray light is eliminated.