TDL Analyzer | Tunable Diode Laser Analyzer | TDL Spectroscopy
TDL Analyzer

Tunable Diode Laser Analyzers

Low-Maintenance TDL Analyzer for Gas Measurement

Tunable diode laser analyzers (TDL analyzers) are gas analyzers designed for measuring the concentration of specific species within a gas mixture using laser absorption spectrometry. TDL analyzers by METTLER TOLEDO are recognized as a low-maintenance tool built for speed and accuracy of measurement, and immunity to background gases. The GPro 500 series of tunable diode laser spectrometers offers a range of process adaptions to ensure your process needs and measurement requirements are met.

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What is a Tunable Diode Laser (TDL) analyzer?

Tunable diode laser analyzers, or TDL analyzers for short, are gas analyzers that are used for measuring the concentration of specific species within a gas mixture using laser absorption spectrometry. In a TDL analyzer, a laser beam, tuned to identify a particular gas species, passes through the gas to a detector. The presence of this gas in the stream causes light absorption and reduced signal intensity. The light collected at the detector of the TDL analyzer is detected by a photodiode and analyzed to quantify the gas concentration.

How can I reduce maintenance and installation costs with a TDL analyzer?

Installing a TDL in situ gas analyzer allows you to eliminate the sample conditioning system that is required with standard extractive techniques. 

In addition, due to the one-flange, folded path concept showcased by METTLER TOLEDO's GPro 500 Gas Analyzer, you can further reduce the installation and maintenance costs related to typical TDL analyzer alignment.

What gas species can be measured with a TDL analyzer?

METTLER TOLEDO GPro 500 TDL Analyzers offer measurement of carbon monoxide (CO%), carbon dioxide (CO2%), hydrogen chloride (HCl), hydrogen sulfide (H2S), gaseous oxygen (O2), methane, ammonia and moisture. These can be paired with a wide range of process adaptions to provide the tunable diode laser analyzer to meet your requirements. For example, an oxygen gas analyzer can be paired with a filter probe to allow you to install an oxygen TDL analyzer in a gas stream that has heavy particulate. That same oxygen gas analyzer can be paired with a wafer adaption to create an in-line TDL gas analyzer for oxygen in a small line size (down to DN50).

What are some suitable applications for a TDL analyzer?

TDL gas analyzers are used in a wide range of applications across a variety of industries. Installations are common in chemical industries, petrochemical refining, pharmaceutical manufacturing, and food and beverage production.

In industries such as chlor-alkali, TDL analyzers by METTLER TOLEDO can replace traditional measurement systems for moisture monitoring to prevent compression system corrosion.

A GPro 500 with a filter probe adaption is optimal for process gas analyzers in combustion applications where high dust loads could typically obstruct measurement. This setup is particularly appropriate for fired heaters and boilers.

In inerting and blanketing applications, the use of a non-purge probe on a gas analyzer provides increased safety and reduces running costs.

For in situ gas analyzer measurement in DN50 or 2" pipes when you have high or low velocities or where you wish to avoid flow restrictions, the GPro 500 Wafer Cell adaption provides stable measurement.

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