Spectroscopic NIR gas cells in closed-loop process control application
Continuous spectroscopic analysis of gaseous processes for emissions monitoring or process control has been established firmly across a variety of industries and using a multitude of technologies like NDIR, NIR lasers, QCLs and many more. However, did you know that your existing FT-NIR system can also be used to monitor industrial gas and vapor streams? If you are planning a new installation or have some capacity and ports available on the existing multiplexer it could be used to diversify your range of applications and improve utilization of the spectrometer.
The Typhoon NIR cell by Specac
For more than 20 years Specac has been at the forefront in the development of robust NIR process cells which can be deployed to monitor the composition of vapor and gas process streams at high pressures and temperatures. In the past two decades Specac has worked with a variety of leading experts and customers to mature this technology and develop the Typhoon gas and vapor phase NIR cell.
In the gas phase spectroscopic features become usually sharper and can therefore be separated more easily, leading to exceptional sensitivities and selectivities. See below for an example of a water vapour phase spectrum acquired with a NIR gas cell at a high resolution of 2 cm-1, with the distinct rotational fine structure.
NIR gas cells for monitoring Ethylacetate production
In the next figure several absorption spectra with varying amounts of Ethylene in the process stream have been plotted. NIR gas cells have been used to monitor the start-up and control of a process for the production of Ethylacetate at a main manufacturing unit, with a resolution of 8 cm-1. We have found that using this resolution is the best compromise between speed and accuracy for both liquid and gaseous process streams. One of the big advantages of FT-NIR systems is the fact that you can use them to monitor both liquid and gas stream simultaneously.
Recent developments in sampling technologies, preparation of gas samples and multivariate data analysis make the calibration of these measurement cells much easier than in the past. Specac has got extensive contacts in the PAT industry and academia to help you prepare for an installation.
Read our application note
Related Posts
GET IN TOUCH