Quantifying flare combustion efficiency using an imaging fourier transform spectrometer.

Our research is motivated by the need to assess hydrocarbon emissions from flaring, which is a critical problem of global significance. For example, recent studies have shown that methane destruction efficiency of flaring from upstream oil may be significantly lower than the commonly-assumed figure of 98%; work by Plant et al.1 1 G. Plant, E. A. Kort, A. R. Brandt, Y. Chen, G. Fordice, A. M. Gorchov Negron, S. Schwietzke, M. Smith and D. Zavala-Araiza, "Inefficient and unlit natural gas flares both emit large quantities of methane," Science , vol. 377, p. 1566-1571, 2022., in particular, suggest that this discrepancy amounts to CO2 emissions from 2-8 million automobiles annually, considering the US alone. Similarly, the international energy agency (IEA) estimates a global flare efficiency of 92%2 2 https://www.iea.org/energy-system/fossil-fuels/gas-flaring3 https://www.worldbank.org/en/programs/zero-routine-flaring-by-20304 D.R. Caulton, P.B. Shepson, M.O.L. Cambaliza, D. McCabe, E. Baum and B.H. Stirm, "Methane destruction efficiency of natural gas flares associated with shale formation wells," Environmental science & technology , vol. 48, p. 9548-9554, 2014.5 M-A. Gagnon, S.S. Tremblay, P.Lagueux and M. Chamberland, "Standoff thermal hyperspectral imaging for flare and smokestack characterization in industrial environments," in 5 th workshop on Hyperspectral Image ans Signal Processing: Evolution in remote Sensing , Gainesvilles, FL, 2013, which translates in 8 million tons of CH4 emitted by flares in 2020.Highlighted by these studies and supported by the World Bank3 initiatives toward zero routine flaring emissions, there is an urgent need for oil and gas industry to assess their flare methane emission, and overall hydrocarbon emissions. At the very least, it is critical to identify problematic flare operating conditions and means to mitigate flare emissions. Focusing on remote quantification of plume species, the measurement technique and quantification method presented in this paper is a considerable step forward in that direction by computing combustion efficiency and key components for destruction efficiency4,5 .