Advanced sensor systems for theapplication of LIME technologies in the process industry: a review

Modern computer-integrated manufacturing and engineering (CIME) technologieshave been developed and implemented to improve plant and process design, measurement and control design, and plant operation, together with the economic optimization of flow processes. Almost irrespective of which approach is selected for obtaining these results, success or otherwise is based on some process measurements, involving predominantly either temperature, pressure or flow. Optical sensors are often being adopted for these tasks not only because of their non-intrusive nature, but also in view of their reliability, together with their high response speed, intrinsic resolution and increasing ruggedness. In addition, the development of new measurement capabilities such as easy adjustment for operating range, compensation for effects of environmental conditions and self-diagnosis, has given a considerable level of “intelligence” to current sensors, which are smarter, smaller and cheaper than ever before.

This paper reviews and discusses the implementation of advanced sensor systems for onlinemeasurements of process streams with emphasis on hot, dirty, hostile and multiphase environments. The requirements for the integration of the information from the sensors in a CIME environment are considered, taking into account the different levels of automation of typical processes. Novel methodologies, such as fiber-optic sensors, semiconductor materials, image processing and data analysis are discussed, as well as the use of "intelligent" instruments as part of the push towards higher quality.