Optimal Design Scenario for Overall Pigging Drying and Gas Displacement of Gas Transmission Pipeline Project

This paper presents two design scenarios for overall pigging drying and gas displacement of gas trans-mission pipeline project. This gas pipeline project, Ji'nan to QiLu gas pipeline, 134 km in length and 508×7.9 mm, was put into use in 2002. Before commissioning, whole pipeline pigging drying and gas displacement were made according to the optimal design scenarios. On the basis of analysis results and field feasibility in season, temperature and humidity, the pigging drying and gas displacement scenario, the 2nd scenario (methanol plus nitrogen) was determined. This scenario was successfully carried out in March, 2002.