Detection, localization, and quantification of single-source methane emissions on oil and gas production sites using point-in-space continuous monitoring systems

We propose a modular framework for methane emission detection, localization, and quantification on oil and gas production sites that uses concentration and wind data from point-in-space continuous monitoring systems. The framework leverages a gradient-based spike detection algorithm to estimate emission start and end times (event detection) and pattern matches simulated and observed concentrations to estimate emission source location (localization) and rate (quantification). The framework was evaluated on a month of non-blinded, single-source controlled releases ranging from 0.50 to 8.25 h in duration and 0.18 to 6.39 kg/h in size. All controlled releases are detected and 82% are localized correctly; 5.5% of estimated events are false positives. For emissions ≤1 kg/h, the framework underestimates the emission rate by −3.9% on average, with 90% of rate estimates falling within a percent difference of [−74.9%, 195.2%] from the true rate. For emissions >1 kg/h, the framework overestimates the emission rate by 4.3% on average, with 90% of rate estimates falling within a percent difference of [−49.3%, 78.8%] from the true rate. Potential uses for the proposed framework include near real time alerting for rapid emission mitigation and emission quantification for use in measurement-informed inventories on production sites.