The Incredible Shrinking Sampling System

Sophisticated and reliable, today's process analyzers can do everything from measuring moisture in a single hydrocarbon gas stream, to monitoring fluid composition at a number of points in the process. But even the most advanced analytical device is only as good as the mechanical system that conveys

the sample to it. In fact, sampling systems, which are responsible for extracting, collecting and preconditioning a sample; transporting it to the analyzer; and then disposing of the it (or returning it to the process line), are the cause of 70-85% of analyzer downtime, according to industry specialists. For the many who have tried to improve the design, the challenge has always been developing a sampling system that is easy to assemble and maintain, robust and precise in its delivery of the fluid.

Enter modular or surface-mounted sampling systems (SMSS), the applications for which originated in the semi-conductor industry, and were adapted to the chemical, petrochemical and petroleum industry through the so-called Generation I (Gen. I) design modifications proposed by the Center for Process Analytical Chemistry's (Univ. of Washington, Seattle; www.cpac.washington.edu) New Sampling/Sensor Initiative (NeSSI), a neutral forum where users and vendors discuss ways to modularize, miniaturize and introduce "smarts" to process analyzer system components.