Research on the leakage monitoring of oil pipeline using BOTDR

Abstract

It's very important to detect the leakage of oil pipeline timely and accurately in order to reduce the losses and ensure the smooth operation of oil pipeline. However, the leakage monitoring of the pipeline is difficult because normally the pipeline is very long and is often buried underground or underwater. Brillouin optical time domain reflectometry (BOTDR), which can distributedly measure the temperature of fiber, has good potential in monitoring the leakage of oil pipeline. In this paper, the feasibility of monitoring the leakage of oil pipeline by using BOTDR is investigated with both laboratory experiments and field tests. The principle of the BOTDR is given at first. Then laboratory experiments are carried out to demonstrate the effectiveness of BOTDR in the leakage monitoring. Several sensing cables with different structures are evaluated in the experiments by comparing their effectiveness in the leakage monitoring and four kinds of laying styles of the sensing cables are compared as well. After that, field tests are carried out by simulating the leakage of oil pipeline. The monitoring effects for different leakage amounts are tested with BOTDR. The sensing cable suitable to monitor the leakage of oil pipeline is chosen by considering both the effect of leakage monitoring and the economics. A few laying styles are compared by testing the sensitivity of detecting the leakage of pipeline. Testing results show that the laying style of straight line along the pipeline can detect the leakage of 1.1m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> /h. A much more sensitive laying style by wrapping up the sensing cable and pipeline with plastic film can detect the leakage of 0.1m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> /h.