Methane leakage from oil and gas pipelines leads to safety risks and climate impacts. Pan-tilt unit (PTU)-based techniques rely on single-point measurements and are highly susceptible to wind interference, and gas imaging approaches have high cost and limited performance, making accurate and comprehensive detection challenging.

In a study published in Environmental Science & Technology, a team led by Prof. ZHANG Zhirong from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences developed a high-performance laser-based three-dimensional methane gas cloud imaging telemetry system, which enables visualizing micro-leakages, accurately locating leakage sources, and quantitatively retrieving emission rates.

Researchers first developed a detection method based on tunable diode laser absorption spectroscopy, which introduces dynamic scanning in the detection process. Based on this method, they developed a methane imaging telemetry system that integrates an optical transceiver module, a hardware circuit module, a self-developed scanning PTU, and a host computer.

The system adopted a coaxial transmit-receive optical path design which enhances the coupling efficiency of long-distance backscattered signals while reducing optical losses.

By combining scanning data with wind simulations, researchers developed a flux-based inversion method to estimate methane leakage rates. They achieved accurate measurement of emissions and supported more efficient monitoring and control of pipeline networks.

The new system developed in this study enables methane leakage detection to move from qualitative assessment to quantitative measurement, supporting more intelligent energy management.