Laser Methane Emission Monitoring Based on Harmonic Ratio Feature and Estimation of Absorption Pulse Parameters

Monitoring of methane from oil and natural gas operations is essential to mitigate environmental risks and promote sustainable practices. The method is an effective tool to detect methane presence and compute methane concentration under condition of low signal to noise ratio. The proposed adaptive time synchronous moving average (ATSMA) and pulse signal fusion of laser signal allow to reduce measurement noise. The proposed ATSMA method reduces the random noise level in terms of root mean square error by 10 times less than the established method. The harmonic ratio features and time–amplitude features improve taking into consideration the properties of the absorption signal and pulse allow to improve the methane estimation accuracy. The proposed method provides linear regression model (R2 = 0.995) with one dependent variable (time–amplitude centroid area of the absorption pulse) for estimating methane concentration for the measured absorption signal.