Use of an unmanned aircraft system to quantify NO_<i>x</i> emissions from a natural gas boiler

• Main Authors: B. Gullett, J. Aurell, W. Mitchell, J. Richardson
• Format: Article
• Language: English
• Published: Copernicus Publications 2021-02-01
• Series: Atmospheric Measurement Techniques
• Online Access: https://amt.copernicus.org/articles/14/975/2021/amt-14-975-2021.pdf

<p>Aerial emission sampling of four natural gas boiler stack plumes was conducted using an unmanned aerial system (UAS) equipped with a lightweight sensor–sampling system (the “Kolibri”) for measurement of nitrogen oxide (NO), and nitrogen dioxide (NO<span class="inline-formula">₂</span>), carbon dioxide (CO<span class="inline-formula">₂</span>), and carbon monoxide (CO). Flights (<span class="inline-formula"><i>n</i></span> <span class="inline-formula">=</span> 22) ranged from 11 to 24 min in duration at two different sites. The UAS was maneuvered into the plumes with the aid of real-time CO<span class="inline-formula">₂</span> telemetry to the ground operators and, at one location, a second UAS equipped with an infrared–visible camera. Concentrations were collected and recorded at 1 Hz. The maximum CO<span class="inline-formula">₂</span>, CO, NO, and NO<span class="inline-formula">₂</span> concentrations in the plume measured were 10 000, 7, 27, and 1.5 ppm, respectively. Comparison of the NO<span class="inline-formula">_<i>x</i></span> emissions between the stack continuous emission monitoring systems and the UAS–Kolibri for three boiler sets showed an average of 5.6 % and 3.5 % relative difference for the run-weighted and carbon-weighted average emissions, respectively. To our knowledge, this is the first evidence of the accuracy performance of UAS-based emission factors against a source of known strength.</p>