Natural Gas Pipeline Network System Optimization Design Study

The exploitation and utilization of natural gas does not depart from the transportation of pipeline system. The scroll exploitation is commonly introduced in gas field in our country. It is necessary to adjust and rebuild gas gathering and transportation system because the discovery of new gas field and the exhaustion of old gas field. Therefore, the study on optimal design of gas gathering and transportation system has important meaning.By studying many domestic and abroad papers, following closely the recent study on optimal design of gathering pipeline system, and combining with the actual state of natural gas gathering pipeline system in the west part of Sichuan, We make a deep study on optimal design of gas gathering and delivering system, it includes topological optimization and structure parameter optimization of gas pipeline system.In this paper, a multilevel optimization method has been adopted, which includes the optimal partition of gas wells, the optimal position of gathering station, the optimal topology of the main and lateral gas network, and the parameter optimization. According to the difference of exploitation process in gas field, a model on optimal topology of gas network is established to make the investment expenses minimum, and make it out by topological and geometrical method. On the basis of optimal topology, a model on structural parameter optimization of gas network is also established to make the net investment expenses minimum. Moreover, the connection of flowrate, pipe diameter, pressure, pipe length, compression ratio and compressor number has been considered. It adopts a discrete complex variable optimization method to resolve this model.Optimal design software of gas gathering pipeline network system with Visual C++ 6.0 has been developed, according to the character of pipeline network system and adopting optimization theory and method. There are wide adaptability, easy operation and high accuracy in the software. It has successful practice in natural gas pipe network building of west part of Sichuan. In other gas field, it also can be used in optimal analysis and emulation of natural gas pipe network.