Session: 08-02: High Hydrogen Gas Turbine

Paper Number: 151912

Leak Detection and SOx Emissions Tradeoffs With Odorized Hydrogen–Natural Gas Fuel Blends in Gas Turbines 

The scalable, dispatchable operation mode leveraged by modern gas turbine power generators exploits pipeline distribution of gaseous fuels with no natural color or odor such as natural gas (NG) and potentially hydrogen (H₂). To reduce fire and explosion hazards in the event of leakage, regulations in many countries require that such fuels be doped with pungent malodorants to enable early leak detection by human smell. These compounds typically rely on fragrant sulfur groups that ultimately generate sulfur oxide (SO_x) emissions when the odorized fuel is burned. To mitigate negative air quality and environmental impacts associated with SO_x pollution, many countries also restrict SO_x emissions from gas turbines, inducing a fundamental tradeoff between upstream leak safety and end-use SO_x emissions. Historically, this tradeoff has not been a significant issue, as odorant concentrations used in current NG distribution networks do not generate sufficient SO_x emissions to warrant regulatory concern. However, this paper shows that SO_x emissions issues may become relevant for proposed future H₂ distribution networks and H₂ turbines, where the tradeoff between leak safety and SO_x emissions is over four times stronger. This disparity arises from the lower molar heating value and broader flammability limits of H₂ relative to NG, which are both shown to elevate SO_x emissions in the case of H₂. Among several other important considerations, the paper also discusses how the extreme diffusivity of H₂ and the increased pressures expected in H₂ networks may require greater odorization levels to ensure effective leak detection, inducing even steeper SO_x emissions tradeoffs.

Presenting Author: Christopher Douglas Duke University

Presenting Author Biography: Christopher Douglas' research focuses on fluid and thermal sciences, with an emphasis on flow instability, combustion dynamics, and thermoacoustics. He and his collaborators develop theoretical and numerical methods to analyze, understand, and control the behavior of high-dimensional nonlinear systems encountered in engineering applications including turbines, rockets, and other energy systems, as well as in diverse natural phenomena such as atmospheric mixing and supernovae. His broader research interests include energy decarbonization and pollutant emissions abatement, with particular attention to alternative energy carriers like hydrogen and ammonia.

Authors:

Christopher M. Douglas Duke University
Alexander Gupta EPRI
Eladio Knipping EPRI
Thomas D. Martz EPRI
David Robert Noble EPRI