Foreign oil and gas pipeline abandonment methods and enlightenment

In China, some pipelines shall be abandoned, but there is no actual operation experience available for pipeline abandonment. In this paper, foreign experience on oil and gas pipeline abandonment was investigated and reviewed, and foreign abandonment methods for land and submarine pipelines were illustrated. For land pipelines, their abandonment method is firstly determined preliminarily according to abandonment option matrix. Then, the pipeline is assessed on site, and the initially determined abandonment method is modified by analyzing multiple factors comprehensively, such as pipeline status, abandonment cost and environment. And consequently, the ultimate pipeline abandonment method is determined secondarily. The determination of submarine pipeline abandonment methods is mainly dependent on the local environmental protection laws and regulations. Submarine pipelines are mostly abandoned in place while some sections located in special positions shall be removed. Finally, different kinds of pipeline abandonment cases were presented to provide the reference for the abandonment of oil and gas pipelines in China.