The lead stories seem to always be about control systems, software and networking, but a good portion of the past 25 years' progress in quality and efficiency of production must be credited to improvements in technology and broader implementation of process analyzers. Here's an overview of their evolution, as chronicled in the first 300 issues of Control magazine.
In his October 1992 "Around the Loop" column, Terry McMahon described analytical instrumentation as a 20th century phenomenon. "Beginning in the first decade of this century with the work of Tsvett in Russia (chromatography) and Lord Kelvin in Great Britain (mass spectrometry), analytical technologies have proliferated," he wrote. Post-World War II intelligence revealed that the German chemical industry had been using on-stream, non-dispersive, infrared analyzers for more than 20 years, but it wasn't until the 1950s that U.S. industrial laboratories began to use analytical instruments on a large scale for monitoring production processes.
Union Carbide developed on-stream gas chromatography and the DuPont Co. "began experimenting with on-stream UV photometry in connection with a new process for the production of titanium dioxide," wrote McMahon. Union Carbide spawned Greenbriar, Bendix and Combustion Engineering, which became part of ABB Process Analytics, and DuPont created Ametek Thermox.
In February 1989, contributing editor Mark Weiss wrote, "Today, there is a concerted effort to incorporate state-of-the-art process analyzers into the process control loop of industrial manufacturing processes. The goals are to assure compliance with environmental, health and safety regulations; improve efficiency by optimizing manufacturing processes to reflect the quality of raw materials; lower costs by eliminating the manufacture of ‘off-spec' batches; improve quality by manufacturing to tighter tolerances; and increase profits by efficiently and cost-effectively manufacturing the product right the first time."
Weiss described the available technologies and typical applications of near-infrared (NIR), non-dispersive infrared (NDIR), Fourier transform infrared (FT-IR), ultraviolet-visible (UV-Vis), X-ray fluorescence (XRF), gas chromatograph (GC), supercritical fluid chromatograph (SFC), mass spectrometers, high-performance liquid chromatograph (HPLC) and ion chromatograph, as well as online titrators and wet chemical analyzers.
Commenting on instrument reliability, Weiss said, "Failure is probably one of the major reasons analyzers are not more widely used. Process analyzers need to be treated as sophisticated systems that require major manpower for design, maintenance and training."
Over the following decades, as shown in the accompanying timeline, Control reported how advances in materials, miniaturization, standardization, electronics, software, automation and communication made process analyzers less expensive, as well as more useful and reliable. And the constant push for better product quality, lower costs, emissions control and the ability to prove it led to a proliferation of analyzers in the process industries.