Research On Steady - State Operation Optimization Of Compressor Main Line

In recent years, the development and utilization of natural gas showed a rapid growth trend, because of the natural gas production and consumption of distance is usually far, it needs to build a large number of long-distance gas pipeline to meet the demand for natural gas transportation. Energy costs of long-distance gas pipeline is a major part of the total cost of its operation, and the compressor stations along the pipeline has a variety of combinations, there is a big difference between the energy consumption of different combinations of the compressor. By a suitable optimization method to find the minimum energy consumption, has important practical significance for rational management and rational use of energy of long-distance gas pipeline.Specific contents and main conclusions are as follows:(1) There is a big difference for the long-distance gas pipeline compressor station energy consumption of different combinations of features, the objective function is minimum energy consumption of compressor station, and the constraint conditions are gas pressure constraints, pipeline strength constraints, pipeline pressure drop equation, compressor equation and pipe flow balance constraints. Then put forward the optimization variables and establish steady-state operation optimization model of long-distance gas pipeline.(2) According to the analysis, equality constraints of optimization model include the basic equations of the steady-state simulation, so the steady-state simulation is basis and prerequisite for optimization. In this paper, the steady-state gas pipeline node was established simulation model, using LU decomposition method and damping Newton-Raphson method to solve the steady-state simulation model. The steady-state simulation model is basis for solving optimization.(3) Steady state operation optimization variables of long-distance gas pipeline include continuous variables and integer discrete variable compressor station combinations. In order to solve the optimization model, first list all combinations of discrete variables. On this basis, use a linear approximation to solve the steady-state gas pipeline operation optimization model. Mathematical methods linear approximation of the process used for the simplex method. And for the simplex method may be beyond the vertex of the feasible region or deviate from the direction, this paper improves the simplex method.(4) Select West to East Gas Pipeline as the object of study, collect length, diameter, height, station layout, gas flow of the compressor and pipeline operating data and so on. Whether compressor characteristic equation for each parameter directly related to the accuracy of the correct optimization, so fit the operating data of the compressor of west to east gas pipeline and get the characteristic equation of the compressor. Then calculate the operating data of the west east gas transmission line in four seasons, and get the optimal operation scheme of the minimum energy consumption of compressor of each season.