Safe and environment-friendly disposal of onshore abandoned oil and gas pipelines

At present, the demand for safe and environment-friendly disposal of onshore abandoned oil and gas pipelines in China is increasing, but so far, systematical and scientific pipeline abandonment technologies and standards have not been established yet. In this paper, a series of analyses were performed on safe and environment-friendly disposal method, environmental impact assessment, and pipeline abandonment technologies. Results show that pipeline abandonment mode can be selected reasonably by combining the general principle with the comparative assessment method. The environmental/ social/economic impact assessment shall be taken as an important part of abandonment plan to provide the support for analyzing the effect of abandonment engineering activities and developing the scientific mitigation measures. Thorough cleaning of pipeline residue is the important technical means to ensure safe and environment-friendly abandonment of pipelines. The residue inside pipelines can be highly cleaned by means of the conventional pigging or the combined cleaning technology, so as to satisfy the requirements on grouting and plugging of special segments, and quick and safe removal of large-scale pipelines. In a word, the abandoned pipelines can be disposed in a safe and environment-friendly way by using multiple measures.