Advanced Spectral Sensing Methods for Process Monitoring Applications

Analytical measurement to determine the quantitative composition of sample mixtures is gaining in importance alongside the widespread measurement of basic physical parameters such as level, temperature or pressure. It is becoming a key factor in the safe operation and control of chemical processes in a wide range of applications. miniaturized analytical systems and spectral sensors based on molecular absorption in the near or mid-infrared range are suitable in many cases to meet specific user requirements such as cost-effectiveness, integrability and reliability. [1]. The paper provides a brief overview of spectral technologies in the near infrared region for chemical process monitoring, in particular on the measurement of liquids. We focus on two measurement systems with different spectral selection principles and performance capabilities. One of the systems is based on the use of Micro Electro Mechanical System (MEMS), the other one uses light emitting diodes for spectral selection. Their design and principles, with respect to the sample implementation, will be described. Furthermore, aspects of calibration development will be pointed out.