Application of Sapphire-Fiber-Bragg-Grating-Based Multi-Point Temperature Sensor in Boilers at a Commercial Power Plant

Journal Article · Sun Jul 21 00:00:00 EDT 2019 · Sensors

DOI: https://doi.org/10.3390/s19143211 · OSTI ID:1543345

Yang, Shuo; Homa, Daniel ; Heyl, Hanna; Theis, Logan; Beach, John; Dudding, Billy; Acord, Glen; Taylor, Dwyn; Pickrell, Gary; Wang, Anbo

Readily available temperature sensing in boilers is necessary to improve efficiencies, minimize downtime, and reduce toxic emissions for a power plant. The current techniques are typically deployed as a single-point measurement and are primarily used for detection and prevention of catastrophic events due to the harsh environment. In this work, a multi-point temperature sensor based on wavelength-multiplexed sapphire fiber Bragg gratings (SFBGs) were fabricated via the point-by-point method with a femtosecond laser. The sensor was packaged and calibrated in the lab, including thermally equilibrating at 1200 °C, followed by a 110-h, 1000 °C stability test. After laboratory testing, the sensor system was deployed in both a commercial coal-fired and a gas-fired boiler for 42 days and 48 days, respectively. The performance of the sensor was consistent during the entire test duration, over the course of which it measured temperatures up to 950 °C (with some excursions over 1000 °C), showing the survivability of the sensor in a field environment. The sensor has a demonstrated measurement range from room temperature to 1200 °C, but the maximum temperature limit is expected to be up to 1900 °C, based on previous work with other sapphire based temperature sensors.

• Sponsoring Organization: USDOE Office of Fossil Energy (FE)
• Grant/Contract Number: FE0012274
• OSTI ID: 1543345
• Journal Information: Sensors, Journal Name: Sensors Journal Issue: 14 Vol. 19; ISSN SENSC9; ISSN 1424-8220
• Publisher: MDPI AGCopyright Statement
• Country of Publication: Switzerland
• Language: English