Viability of video imaging spectro-radiometry (VISR) for quantifying flare combustion efficiency.

Abstract

Implications statement: A technique called "Video imaging spectro-radiometry" (VISR) has been developed for quantifying the combustion efficiency of flares based on spectrally resolved imaging. In the original version of this technique, a multispectral camera measures emissions over spectral bands aligned with key absorption features of CO2, CO, and the C-H stretch absorption band of alkanes. A local combustion efficiency map is defined from the ratio of the broadband pixel intensities, which is then converted into an overall combustion efficiency through pixel-averaging.While this technique has been validated through extractive sampling studies, in this work we analyze simulated measurements using a CFD simulated steam-assisted flare. In this context the CFD data serves as a ground truth. The results call into question the veracity of the instrument model used to convert the local CE estimates into a global CE for the flare, as well as the ability of this technique to capture cold methane that may be diverted from the combustion zone through aerodynamic stripping. These findings have important implications for emerging technology-based emission regulations, as well as the development of new remote sensing technologies for measuring flare performance.