多源单汇液态轻烃管网系统运行优化MINLP模型

MINLP model for operation optimization of multi-source single-sink liquid light hydrocarbon pipeline network system

目前中国油气田多源单汇液态轻烃管网系统主要采用间歇混合输送模式运行,将不同种类的液态轻烃从多个产烃站场混合输送至下游储备库,现场运行计划主要依靠人工经验制定,存在启停泵频繁、运行能耗较高、管网水力波动较大等问题。鉴于所建模型大多求解过程较复杂、计算结果经济性不高、启停泵次数较多,基于离散时间、定时步表达法,考虑各约束条件,以各产烃站场外输泵运行费用与外输切换操作成本总和最小为目标函数,建立了混合整数非线性规划(MINLP)模型,采用分段线性化方法处理非线性约束,并采用大规模数学规划求解器Gurobi进行求解。以中国某实际运行的多源单汇液态轻烃管网系统作为算例进行计算,求解耗时245.7 s,求解结果提高了管网运行的稳定性、安全性及经济性,符合现场操作工艺。(图7,表4,参28)

At present,batch mixed transportation mode is mainly adopted in the multi-source single-sink liquid light hydrocarbon pipeline network system of China’s oil and gas fields.In this mode,different kinds of liquid light hydrocarbon are mixed and transported from multiple hydrocarbon-producing stations to the downstream storage.In the process of transportation,however,the on-site operation planning mainly depends on personnel experience,which may lead to frequent pump startup and shutdown,high operation energy consumption,significant pipeline network hydraulic disturbance and other problems.Based on the discrete time stepping expression method with consideration of various constraints,the mixed-integer nonlinear programming(MINLP)model was built,with the minimum sum of costs,containing transmission pump operation cost and transmission switching operation cost in hydrocarbon production stations,as the objective function.Piecewise linear method was used to deal with the nonlinear constraints,and largescale mathematical programming solver(Gurobi)was used for solution.As a calculation example,one multi-source single-sink liquid light hydrocarbon pipeline network system operating in China was solved,with the solving time of 245.7 s.The solving result improves the stability,safety and economy of the pipeline network operation,and conforms to the field operation process.(7 Figures,4 Tables,28 References)