Ogbole Collins Inalegwu, a doctoral candidate in computer engineering, will defend their dissertation titled “Advanced Optical Fiber Sensor Technologies for Enhanced Monitoring and Safety in Electric Arc Furnaces.” Their advisor, Dr. Jie Huang, is an associate professor in the electrical and computer engineering department. The dissertation abstract is provided below.

The steel industry remains a key driver of global revenue, with electric arc furnaces (EAF) gaining widespread adoption mainly due to their lower carbon emissions and improved energy efficiency. However, optimizing production efficiency while ensuring structural integrity and operational safety requires advanced, data-rich monitoring systems that surpass the capabilities of traditional thermocouples. This work presents real-world implementations of advanced optical fiber sensor (OFS) technologies, with capabilities of offering distributed and multiplexed sensing, immunity to electromagnetic interference (EMI) and corrosion, and compact form factors for seamless retrofitting into existing infrastructure. The study showcases OFS implementation in three critical areas of EAF operation: bottom anode monitoring, spray-cooled shell monitoring for hotspot detection, and burner zone water leakage detection. In the bottom anode, fiber Bragg grating (FBG) and Rayleigh backscattering (RBS) sensors deployed in a 165-ton DC EAF over two months enabled the tracking of bottom anode’s wear, detecting temperature anomalies and providing a better way of informing operators of the estimated service life of the furnace campaign. In the spray-cooled shell, Rayleigh-based optical frequency domain reflectometry (OFDR) was utilized to achieve high spatial resolution (1.3 mm) thermal profiling, enabling real-time detection of hotspots, insights into the optimization of spray cooling strategies, and dynamic operational adjustments to prevent structural degradation. Additionally, within the burner zone, OFS (FBG and RBS) embedded in refractory lining bricks, successfully detected controlled water leaks (≥2.3 cc/min) at temperatures exceeding 500 °C, mitigating the risk of catastrophic steam explosions. These findings highlight the transformative potential of advanced OFS technologies in enhancing monitoring precision, operational safety, and efficiency in modern EAF steelmaking.