Integrated systems for pipeline security
1.Tougher sanctions for the environmental pollution, oil market situation, as well as the growing number of unauthorized tie-ins designed to steal oil and oil products call for improvement of efficiency, reliability and security of the pipeline management. Political motives are by no means of lesser importance: to join the world economic community, Russian oil and oil product transportation companies have to undergo certification in accordance with the international ecological standard ISO 14001.
Since the disintegration of the Soviet Union, the Russian industry inherited a vast network of worn oil- and oil product pipelines. Some of them are under-loaded and in periodic operation, others have been closed down temporarily. From the macroeconomic viewpoint, this state of affairs benefits Russia greatly, enabling the country to hold the leading positions in the European energy market under the current political situation. Yet, from the ecological point of view, it is a national disaster. According to ecologists’ estimates, between 8 to 10 percent of oil produced in Russia is lost “in transit” between the well and the fuel tank, and considerable part of this oil falls on the pipelines. These dozens of millions of tons cause pollution of soil and water, destroy flora and fauna, population habitat and health.
The official statistics of the reasons for oil and oil product pipeline accidents admits fault of operators only in 10 – 15 percent of the total amount of cases, the same percentage falls on pipe and fitting damage occurring during construction and assembly operations, as well as on workmanship defects which could be revealed immediately, rather then after dozens of years since the commencement of operation.
Frequent trunk pipeline accidents present a serious problem for the world oil and gas industry. Annual losses, incurred due to damaged trunk pipelines and other equipment, exceed $ 13 billion in the USA alone, according to the official web site of the Federal Agency for Environmental, Engineering and Atomic Energy Supervision (Rostekhnadzor).
At the same time, the Federal Agency marks a noticeable trend towards considerable increase in the accident rate in Russia due to pipeline surface destruction caused by corrosion and erosion. This happens because pipelines transport highly corrosive media containing hydrogen sulfide, oxygen, carbon dioxide, high salt and abrasive concentrations.
After the long-term pipeline operation, its corrosion (both internal and external) is considered to be the reason of leakage in the majority of cases (50 – 70 percent). But is corrosion a spontaneous and absolutely unpredictable phenomenon? It is not corrosion itself which becomes the reason of ecocatastrophes, but oil spills, the size of which depends on the production standards and personnel qualification, pipe quality and maintenance promptness, on efficiency of the pipeline management on the whole and sensitivity, operating speed and reliability of the leakage detection systems in particular.
2.The range of the proposed means for pipeline leakage detection is rather wide: from primitive leakage detectors utilized in the communal services to aerospace monitoring. However, there is no universal tool available. Pipeline diagnostics by internal devices is characterized by high sensitivity, selectivity and accuracy. Operators can afford performing inner pipeline inspection only every five years, which excludes these methods from the group of on-line control means. Static methods imply oil pumping shutdown for rather long period of time and are used either prior to start-up of new (repaired) sections of pipelines, or could be recommended as additional proving methods when leakage is suspected. The radioactive method is not ecological, the visual or acoustic ones are very labour-consuming, and they require permanent presence of the personnel equipped with special devices at the pipeline.
Parametric methods of leakage detection are in the highest demand and are widely utilized in the pipeline management systems. At present, over 50 companies offer their developments in the area of the leakage detection systems for the main pipelines, different in their physical bases and peculiarities of realization. The main part of the monitoring systems market, which exceeded $ 200 mln long ago and continues to develop by 15 – 20 percent a year on average, belongs to the foreign companies which offer leakage detection systems based on various algorithms.
None of the conventional methods can satisfy increasing requirements of the ecological and industrial safety of the major pipeline facilities. Modern tendency for development of the leakage detection system analytic tool implies application of combination methods which utilize information coming from independent sources. Their top achievement is the methodology for building of an open analytic system capable to combine numerous competing on-line estimates of leakages obtained by different diagnostic algorithms.
It should be stressed that only an integrated system for pipeline security including aerospace and parametric monitoring, visual control over the pipeline route and legal backup may resolve the problems of accidental oil spills and theft from oil- and oil product pipelines.