Analyses of the Process Control and Technical Scheme of Urumchi—Lanzhou Multi-Products Pipeline

The Urumchi—Lanzhou multi-product Pipeline (China western multi-product pipeline, CWPP) is characterized by long distance, multi-delivery points, severe undulating terrain and high-required running conditions. According to technical characteristics and automation level of the stations, the various running states are analyzed, and the process control principles and accident handling methods are also identified. Based on the terrain and sequencing of the transportation process, the pipeline shutdown principles and methods are determined. Calculation methods of the shutdown pressure are proposed considering the temperature drop caused by shutdown. The dynamic optimal control methods of control valves at pressure-reducing stations are also presented considering that multi-product pipeline through the different points with a large drop height can be analyzed by lots of different control modes. Based on the analyses of operating parameters, it indicates that the application of control principles and methods offers guarantee for the pipeline safety and economic operation.