FTIR gas analyser

Accurate gas analysis is critical in monitoring industrial emissions and ensuring safe working environments. Traditional monitoring tools have been used to measure one gas at a time, which can be limiting when multiple compounds are present.

FTIR analysers now identify and measure several gases at once, providing fast, reliable data that supports compliance, safety and efficiency. In this article, we take a closer look at what FTIR gas analysers are, and why you should choose them.

[edit] What is FTIR?

FTIR stands for Fourier Transform Infrared Spectroscopy, which is a technique that measures how molecules absorb infrared light. Each gas has its own unique spectral fingerprint, which represents specific wavelengths absorbed due to molecular vibrations. By detecting absorbed wavelengths, an FTIR analyser identifies the gas and its concentration.

When using an FTIR gas analyser, a beam of infrared light is passed through a gas sample. Absorbed wavelengths are recorded and converted via a Fourier transform into a spectrum that shows which gases are present and their quantities.

[edit] How FTIR works?

FTIR analysers use an interferometer, an optical device with mirrors and a beamsplitter. Infrared light is split into two paths where one hits a fixed mirror and the other hits a moving mirror.

The recombined beams interfere, creating an interferogram that contains all infrared wavelengths at once. As gases absorb different wavelengths, the analyser can recognise multiple gases simultaneously, even in complex mixtures.

The analyser collects a complete spectrum in every scan so data can be reprocessed later without resampling.

[edit] Why choose FTIR?

There are a number of features that make FTIR analysers attractive for industries and regulators. Their multi-gas capability is one of the most important factors as instead of installing separate sensors for each gas, a single FTIR unit is capable of measuring dozens of compounds at the same time.

They also offer great levels of flexibility as updates are handled through software rather than hardware changes, which allows them to adapt if regulations change or new compounds need to be tracked.

FTIR gas analysers also provide real-time results thanks to continuous monitoring which gives operators important, instant information about gas concentrations. They are an important part of non-destructive testing as the gas sample itself is not altered or consumed in any way, meaning that results are both fast and repeatable.

[edit] Advantages of FTIR

Compared with traditional techniques such as Non-Dispersive Infrared (NDIR) sensors or chemical analysers, FTIR is able to offer higher sensitivity by detecting gases at low concentrations. As they capture the full infrared spectrum, FTIR analysers also distinguish overlapping signals from different gases reducing the chance of false results and provide greater levels of accuracy in complex mixtures. They also require less frequent calibration and can remain reliable over long periods.

FTIR analysers offer high levels of efficiency and cost savings, as they can often replace multiple single-gas analysers, and as they are designed to be lightweight and rugged, they are suitable for both fieldwork and fixed installations. They are also important in environmental compliance as industries like energy, waste management and shipping have strict emissions standards that require FTIR analysis.

FTIR gas analysers are more than just monitoring tools as they can capture complete infrared spectra and analyse multiple gases at once, providing a powerful, flexible and cost-effective way to manage emissions, ensure compliance and protect people and the environment.