Modeling The Optimization Of Natural Gas Supply And Marketing Plan Based On Value Chain

With the independence of oil and gas pipelines and the establishment of the National Oil and Gas Pipeline Company,China's natural gas market reform process has continued to accelerate.In the situation where the upstream and downstream markets have been gradually opened and the pipelines interconnection become increasingly perfect,It's required that the enterprises of natural gas supply and demand have to cooperate more efficient.For natural gas production and sales enterprises such as China National Petroleum Corporation,more efficient and flexible methods need to be adopted to optimize resource allocation and sales plans so as to formulate more reasonable production and operation plans.In this paper,the production,sales,trade,storage,and transportation of the CNPC industry are taken as an unified whole for theoretical research.Firstly,a topological structure diagram of the natural gas value chain is drawn based on the relationships between various links.Then,the main factors that affect the overall benefit of the natural gas value chain are analyzed.On this basis,a mathematical model of CNPC's natural gas supply and marketing optimization was established to maximize the overall benefit of the natural gas value chain,in which the gas supply volume of each gas source,the pipeline transportation volume of each pipeline segment and the gas purchase volume of each user are used as decision variables.And the constraints include boundary constraints,infrastructure capacity constraints,material balance constraints,etc.In the process of mathematical modeling,0-1 variables and large M values are added to establised the piecewise linear constraints of natural gas sales ladder pricing.Besides,in view of the non-linear constraints such as the direction of pipeline transportation and the hydraulic pressure drop in the pipeline transportation process,direct replacement method and series expansion method are selected to convert them into linear constraints in order to reduces the difficulty for solving the model.Combined with the design concept of the target planning model,the soft constraint design is made on the target constraints and boundary constraints,so that the model can realize the functions of conventional optimization,fixed sales optimization,fixed production optimization,benefit calculation and customization.Finally,a calculation model is designed using java programming language to achieve the functions of data input,error checking,model solution and result output,which provides a decision-making tool for CNPC's natural gas supply and marketing optimization.