Economic Feasibility of Acoustic Emission Monitoring in CO2 Pipelines: An Experimental Study

CO 2 pipelines are critical for carbon capture, utilisation, and storage (CCUS) and industrial applications. Gas leaks from these pipelines can pose a significant safety hazard, impact the environment, and cause economic losses. When leakage occurs from the high-pressure pipeline, it creates stress waves due to localised energy release, which can be detected by using acoustic emission (AE) sensors. There have been considerable attempts made in literature to monitor leaks and perform source localisation of leaks in CO 2 pipelines using AE, as this technique is non-invasive and can be monitored in real-time. Most of these studies were performed using a straight CO 2 pipeline. However, most of the pipelines using CO 2 transportation will have bends, joints, and valves, which may impact the strength of the AE signal. Also, the economic viability of using the AE for commercial implementation for pipeline monitoring in industries is not well understood. Therefore, to address these knowledge gaps, this paper focuses on understanding the economic viability through an experimental study. Experiments were conducted on a six-meter pipeline with joints, bends and valves. Static test experiments were conducted under different flow coefficients. Also, attempts were made in the study to identify the source localisation of the leak by adjusting the sensor positions. From the experiments conducted, the minimum leak that could be identified from the valve was 0.5 L/min and from the pipeline was 42 L/min. It was also possible to identify the leak location with good accuracy. From the study conducted and based on international prices of CO 2 gas in December 2025, we observed that the industry could save at least $225,482 USD annually by monitoring leaks from a single valve and approximately 18.9 million USD by monitoring leaks from pipelines using acoustic emission. This study lays a strong basis for industries to further investigate the commercial implementation of AE sensors for CO 2 pipelines.