In-situ temperature monitorization in oscillatory flow crystallizer using optical fiber sensors with a Bragg grating inscribed at the fiber tips ends

¹ INESC TEC – Institute for Systems and Computer Engineering, Technology and Science, Porto, Portugal
² Department of Engineering Physics, Faculty of Engineering, University of Porto, Porto, Portugal
³ LEPABE – Laboratory for Process Engineering, Environment, Biotechnology and Energy, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
⁴ ALiCE – Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal

^* Corresponding author: susana.o.silva@inesctec.pt

Published online: 31 October 2024

Abstract

Optical fiber sensors were implemented to measure in-situ temperature variations in an oscillatory flow crystallizer operating in continuous. The sensors were fabricated by cleaved in the middle 8 mm-length fiber Bragg gratings, forming tips with a Bragg grating of 4 mm inscribed at the fiber ends. The geometry of the sensors fabricated, with a diameter of 125 μm, allowed the temperature monitorization of the process flow, inside the crystallizer, at four different points: input, two intermediate points, and output. The results revealed that the proposed technology allows to perform an in-situ and in line temperature monitorization, during all the crystallization process, as an alternative to more expensive and complex technology.