Research On Fuzzy Optimization Operation Of Oil Gathering System Under The Process Of Loop-like Single-Pipeline Mixed With Hot Water

Water-mixed oil gathering is an important technical means to ensure the safety of oilfield production,and also a major production link with huge energy consumption.It can achieve remarkable economic benefits to carry out the research on the operation optimization of water-mixed oil gathering in oilfield.In most of the existing researches,the deterministic optimization theory is used to optimize the operation parameters of water-mixed oil gathering.However,due to the ambiguity of the process boundaries in the production of water-mixed oil gathering,only through the deterministic optimization method the loss of some optimization information will be resulted in.Considering the fuzziness of water-mixed oil gathering production,it is of practical significance to study the fuzzy operation optimization of crude oil gathering and transportation system for saving energy,reducing consumption and enhancing the applicability of the optimization scheme.Firstly,the network structure characteristics of single-pipeline mixed with hot water process are analyzed,and the hydraulic and thermal calculation models of pipe transport are given.Then,based on breadth-first search(BFS)the calculation method of pipe network parameters is established.Combined with the ergodicity of the method,the effective calculation of node parameters and process parameters is realized.This method has the advantages of accurate calculation and easy implementation.Secondly,the objective function is established with the lowest energy consumption and the lowest thermal energy consumption of the oil gathering system,respectively.Taking the head and pressure of the water pump and the heating temperature of the heating furnace as the decision variables,and considering the flow characteristics of the pipe flow,temperature limitation and pressure limitation as the constraints,a mathematical model of deterministic multi-objective operation optimization for the oil gathering system under loop-like single-pipeline mixed with hot water process is established.By linear weighting method the multi-objective optimization is transformed into single-objective optimization,and then the sequential quadratic programming method is used to solve the problem.Thirdly,on the basis of deterministic operation optimization of gathering and transportation system,considering the fuzziness of the feasible boundary for operation parameters in single-pipeline mixed with hot water process,the fuzzy constraints of wellheadbackpressure and station temperature are constructed by using the fuzzy set theory and fuzzy reliability method.The mathematical model of fuzzy multi-objective operation optimization for the oil gathering system under loop-like single-pipeline mixed with hot water process is formed.And the fireworks algorithm is used to solve the problem effectively.Finally,relying on Visual Studio 2010 software development platform and using C#programming language,the proposed breadth-first search process calculation method,deterministic gathering and transportation system optimization theory method and fuzzy gathering and transportation system optimization theory method are put into program implementation.And the "operation optimization platform for the oil gathering system under loop-like single-pipeline mixed with hot water process" is developed.The software realizes the functions of graphical modeling of system pipeline network,simulation operation of single-pipeline mixed with hot water process gathering and transportation,deterministic parameter optimization and fuzzy parameter optimization.With the optimization software,the calculation of an example block is carried out.The results show that both deterministic and fuzzy parameter optimization can significantly reduce the energy consumption cost of gathering and transportation,which can be reduced by 10.2% and 10.7% respectively.The effectiveness of the proposed theoretical method and the software are verified.