Optimization Research Of Structural Layout And Operation Parameters For Annular Oil Gathering Pipe Network

The structural layout and operation scheme of oil gathering pipe network are important factors that influence the construction investment and operation cost of oil gathering system,and they are directly related to the economic benefit of oil field development.Basic on the analysis of process features for oil gathering with hot water mixed in annular pipes,the optimization of structural layout and parameter for this kind of pipe network is studied in this paper,with the minimum construction and operation cost of oil gathering pipe network being the objective function.Ant colony algorithm and genetic algorithm are combined to solve the overall layout optimization model,and the well groups and station locations are optimized synchronously.In ant colony algorithm,the determination of membership is converted to the choice of routes,and well group dividing is finished through controlling the metastatic mode and probability during the process of route searching.In genetic algorithm,the information of station locations is stored in chromosome,and the best locations can be searched in the whole feasible region.Ant colony algorithm is called to obtain the best well group dividing scheme for each station distribution that possibly appeared.Comparing the overall layout scheme resulting from synchronous and stepwise optimization,it indicates that synchronous optimization algorithm can avoid the effect of initial value to the optimization process,enlarge the searching space effectively.And the objective value of well group and station location scheme is reduced more than 10%.Based on the overall layout scheme of pipe network,ant colony algorithm and genetic algorithm are combined to solve the optimization model of annular pipe structure.The division of subsets and the connection of well fields in subsets are finished synchronously.Genetic algorithm is used to determine the structural parameter of loops,including the number of loops in each station,the number of wells in each loop.Ant colony algorithm is used to determine the division scheme of subsets and the connection order of well fields in each subset.Comparing the process and results of synchronous and stepwise optimization,it shows that the synchronous optimization algorithm can obtain better combination scheme of loop amount and well amount in each loop.The objective function value of all the annular pipe structure is about 20% lower than stepwise optimization.For the parameter optimization model of annular oil gathering pipe network,genetic algorithm is adopted to solve it.The diameters,temperature of water mixed,amount of water mixed,pressure of water mixed are stored in chromosome.The expression method of parameters at each node is introduced,and objective function value is calculated for every group of optimization variables.Use the penalty function to handle the constraint condition,in order to keep the solution feasible.Optimization results show that the algorithm has strong stability and adaptability,and optimum operation scheme is obtained for all the loops.