Study On Comprehensive Evaluation Of Peak Load Regulation Of Dendritic Natural Gas

With the development of domestic gas pipeline construction,a large nationwide gas transmission network is formed. Its variation law is more and more complex with the expansion of natural gas pipeline network, therefore, it is much more difficult to keep the balance of gas supply and demand.The balance between supply and demand of natural gas is mainly achieved by the peak-shaving of thegas supply system,due to structural complexity of large-scale gas pipeline network and other features.it is difficult to make feasible technique and reasonable economy desion of the best schemes of peak-shaving.According to the voluminous information research and actual production, only will we integrate the computer simulation and evaluation methods can we get the best schemes of peak-shaving which is aiming at the economic and social benefits. So this paper carried out a study of the following aspects:First of all, on the basis of domestic and international data collection and field research, peaking on the gas pipeline technology, comprehensive evaluation method and evaluation application status in the oil and gas storage and transportation projects were collected, collated and absorbed, the peaking technology and comprehensive evaluation of technical development at home and abroad research results are analyzed and compared.Secondly, lots of Sichuan-East Gas Pipeline running information and data are collected, the pipeline simulation software SPS is understood, the Sichuan-East gas pipeline simulation model is established. The appropriate boundary conditions and initial conditions are introduced according to the concrete structure, operating conditions as well as gas law of users of Sichuan-East gas pipeline, based on this, the parameters of network are constantly changed, so the best schemes of peak-shaving of with or without compressor station in operation is finally obtained.Then,comprehensive evaluation index system and the corresponding index weights of with or without compressor station in operation are identified. Three models of natural gas peak-shaving are established including the rank-sum ratiomethod, the excellence method, the cumulative value methodand the linear weighted summation method. Based on the three models, two peaking programs are evaluated, and different ranking of alternatives are got.After comprehensiveevaluation,Maximum compatibility degree is introduced to integrate all results of the three methods mentioned above,and at last, the best schemes are got,they are ranked with the merits of three methods.Finally, Sequencing results of two conditions were compared and analyzed. Studies have shown that:When compressor station don’t operate the excellence is the best evaluation method. Thus in the premise of guaranteed supply, the excess gas is allocated to downstream users as much as possible to get a maximum economic benefit. While when compressor station operate, the linear weighted summation is the best evaluation method. Under this condition, the distribution of natural gas is closely related to the run power of gas station’s pressure. The best schemes of peak-shaving should guarantee the safety and stable gas supply, what is more, the economic benefits should be taken into account too.