Leakage in oil and gas infrastructure, often cause significant financial losses, severe damage to the environment and raises public concern. In order to minimize the impact of spills, quick detection of a leak and a rapid response are needed. The systems currently employed to detect pipeline leakage range from simple visual checking to complex hardware and software systems such as mass balance, pressure point analysis, flow deviation, acoustic emission systems, and fibre-optic-based sensing technologies. These methods are useful, but there are certain limitations. The main drawback of the majority of these leak detection technologies is that they detect leakage indirectly, often unable to detect the leakage until the major spill.
The preventive monitoring system and direct detection of hydrocarbon leakage are urgently needed to enable fast response and timely repairs with less deleterious effects. Research is being conducted for the development of a functional prototype and environmental testing of in-situ carbon nanotube (CNT) nanocomposite based sensors for hydrocarbon leakage detection. The CNT nanocomposite offers a unique approach to the direct hydrocarbon leakage detection in pipelines and aboveground storage tanks (ASTs).
Expanding the study from the previous report of sensor characteristics under the optimal ambient condition, it was further investigated to identify the sensor performance under harsh conditions such as the underground (exposed to the soil) with compost and moisture, high pressure, changing temperature and long-term exposure to the outdoor environment. Investigation of the sensor behavior is studied, and a performance matrix is developed that accounts for the change in sensor response to various environmental conditions. Results showed that the proposed CNT nanocomposite sensor was applicable under given conditions with immediate responses while maintaining high sensitivity to the hydrocarbon leakage.
Once a list of sensor detection specifications is defined, it is anticipated that the CNT sensor technology is applicable as part of a robust, reliable and accurate early detection system for the pipeline industry.