Corrosion Resistant FBG-Based Quasi-Distributed Sensor for Crude Oil Tank Dynamic Temperature Profile Monitoring
da Silva Marques, R. S. Marques
; R. N. Ribeiro, M. R. N. Ribeiro
; Pontes, M. J. Pontes
Sensors Vol. 15, Nº 12, pp. 30693 - 30703, December, 2015.
ISSN (print): 1424-3210
ISSN (online): 1424-8220
Scimago Journal Ranking: 0,65 (in 2015)
Digital Object Identifier: 10.3390/s151229811
This article presents a corrosion resistant, maneuverable, and intrinsically safe fiber Bragg grating (FBG)-based temperature optical sensor. Temperature monitoring is a critical activity for the oil and gas industry. It typically involves acquiring the desired parameters in a hazardous and
corrosive environment. The use of polytetrafluoroethylene (PTFE) was proposed as a means of simultaneously isolating the optical fiber from the corrosive environment and avoiding undesirable mechanical tensions on the FBGs. The presented sensor head is based on multiple FBGs inscribed in a lengthy single mode fiber. The sensor presents an average thermal sensitivity of 8.82 ± 0.09 pm/°C, resulting in a typical temperature resolution of ~0.1 °C and an average time constant value of 6.25 ± 0.08 s. Corrosion and degradation resistance were verified by infrared spectroscopy and scanning electron microscopy during 90 days exposure to high salinity crude oil samples. The developed sensor was tested in a field pilot test, mimicking the operation of an inland crude tank,
demonstrating its abilities to dynamically monitor temperature profile.