17 Sep 2020

NIR process cells

Discover how NIR process cells can help you to unlock the true potential of your chemical plant. Using the long expertise of Specac engineers of 25 years in designing robust and rugged NIR spectroscopy tools you can measure the composition of your valuable hydrocarbon process streams on-line, in-situ and instantaneously. Instead of taking hazardous and time-consuming samples your operators have all the information they need at hand to run the chemical plant safely and effectively.
A petrochemical plant typically consists of many different reaction sections, including a reactor, flash tanks, distillation units, driers and many more. Although great strides have been made in recent years to simulate the compositions of the various process streams, the most consistent benefits for process optimization are derived if regular analytical measurements are conducted on critical process streams within the unit.  The process stream can contain liquids, gases or even solids (catalyst particles, rust, dirt) and sometimes mixtures thereof. Due to these variable compositions, high pressures, temperatures and corrosivity, sampling of these streams for measuring the contents off-line in a chemical laboratory on site is difficult, hazardous and highly variable.
How can you then measure these hazardous process streams remotely, reliably and safely?
This is where the concept of on-line analysis using spectroscopic tools from Specac comes into play, by in fact taking the laboratory to the plant at the point of interest. By using NIR spectroscopy you are not only avoiding sampling on a regular basis, but the concept of on-line analysis also allows you to look at incremental improvements of the chemical process by feeding the results directly into the distributed control system (DCS) and control your reaction sections that way.
Today in industry NIR spectroscopy is still the standard method of choice for the application of process analytical technology.  In industrial organic chemistry most process run at pressures of up to 100 bars and typically temperatures of up to 200 oC, sometime even hotter. Using NIR spectroscopy together with industry leading spectroscopic accessories from Specac you can measure even the most hazardous streams on-line and derive massive benefits both in terms of control and safety of your plant.
For example, one of the most important industrial organic processes involves the dehydrogenation of Ethylbenzene to Styrene, an important intermediate for the production of polymers. In the production process a distillation column is used to separate Styrene and unreacted Ethylbenzene. Atmospheric boiling points are 136.2 for Ethylbenzene and 145 oC for Styrene, which is fairly close. The differences in the molecular structures of Ethylbenzene and Styrene make it possible to measure the exact concentrations of all the components and to optimize and fine-tune the operation of the distillation column instantaneously based on the results of the spectroscopic analysis.
Another important industrial process is the production of acetic acid, from the reaction of methanol and carbon-monoxide at high pressures and temperatures. Acetic Acid is an important intermediate chemical for the manufacturing of solvents like ethyl acetate and for key ingredients in paints like vinyl acetate monomer. Recently we have published an application note on how Specac NIR cells can be used in the production of Acetic Acid to improve throughput and reduce the amount of by-products (click here).
Specac process cells can be connected remotely to the widest choice of commercially available FT-NIR spectrometers using standard SMA 905 connectors. A large range of process analytical applications on a petrochemical site can now be realized simultaneously with just one spectrometer and an optical multiplexer by the combination of Specac gas, vapour and liquid cells.
Contact us for more information on our complete range of NIR process cells