Design And Operating Optimization Of Natural Gas Transmission Pipeline System

Natural gas is a clean and high-quality energy source. Proportion of natural gas increasein primary energy has great significance for optimizing the energy structure of China, easingthe demand for energy tensions and environmental pressures. As the increasing natural gasdevelopment and use scale in recent years, the constructions of natural gas transmissionpipeline develop rapidly. Thus, Natural gas transmission pipeline system has become largeand complicated, and pipeline construction cost and operating cost increase accordingly.Optimization of design and operation of natural gas pipeline system has great significance inincreasing economic benefits and ensuring safe operation.In this paper, the current research of natural gas transmission pipeline system designoptimization and dynamic simulation of natural gas pipeline system is depicted. In order tooptimize gas pipeline transmission system, technical and economic model of the minimumtotal cost of the system as the objective function is obtained, including the constraints of theboundary conditions, pipeline strength and hydraulics constraints. Using genetic algorithm tosolve the mathematical model, some design variables, such as pipeline diameter, compressorpressure ratio, compressor outlet pressure and pipe wall thickness, are optimized. Bycalculations and comparisons for several cases, model is a reasonable reflection of thediameter, gas pressure and wall thickness for the total cost, verifying the reliability of themodel.For this unsteady feature of gas pipeline, fast transient process and slow transient processmathematical models are obtained by applying the conservation of mass, moment and energy.Characteristic method and implicit centered finite difference method, theories of which forsolving partial differential equations are discussed, are used to solve fast transient processmodel and slow transient process mathematical model respectively. These two models areapplied to specific gas pipeline system and the pipeline pressure trend calculated is same asthe literature value. These models truly reflect the instability of pipeline system, proving itsreliability. This research can be used to guide the practical operation of natural gas pipelines.