"Third Party Interference", whether intentional or accidental, is responsible for more than half of the pipeline failures in the world. The consequences can be catastrophic for people, the environment but also for facilities availability. The project presented here considers the use of a communication optical cable, laid with the pipeline, in order to detect intrusions and also leaks. Field data from an operational test was acquired at the Balhaf LNG facility in Yemen in December 2012.
The LNG plant operations had been subject to numerous sabotage actions, impacting the pipeline feeding gas to the plant, and therefore the plant availability. A security review concluded that there was a need to implement specific security measures to allow early detection of potential threats. The requirement was to minimize new equipment installation in the field, so as to avoid personnel exposure, by making use of the already installed communication optic fiber communication cable.
A fiber optic based detection system was selected. Such systems detect acoustic signals via the optical pulses sent within an optical fiber, known as Rayleigh scattering. For example repeated and regular impacts on soil will trigger an "excavation" alert and a security team can be sent to stop intruders before they reach the pipeline. The advantage of this technology is that it makes use of one of the optical fibers within the communication cable, already installed in the pipeline trench. There is no need to install additional new cables alongside the pipeline.
Since its resulting installation, the system has demonstrated that this technology can reliably contribute to pipeline security by enabling operators to detect and listen to pipeline external threats. Fiber optics can also be used for leak detection. Such detection is based on the continuous measurement of the temperature gradient between the fluid transported and the surrounding ground, the environmental effects on the ground of the escaping product or the multiple acoustic signatures of a leak. This functionality is being tested and evaluated. This technology has the potential to drastically improve operational safety and security for pipelines deployed within challenging environments.