基于动态规划的原油管道运行能耗优化技术研究

Research on energy consumption optimization technology of crude oil pipeline opera⁃tion based on dynamic planning

随着管道老化和站内设备劣化,原油管道整体能耗呈逐年上升趋势。在考虑泵状态、加热炉状态、变频器状态、泵转速、加热炉功率、节流阀压降等决策变量的基础上,建立了以总运行费用最小为目标函数的原油管道运行能耗优化模型,结合总传热系数和水力摩阻系数修正值,采用动态规划算法对最优运行方案进行求解。结果表明,参数修正后,进站温度的平均相对误差为3.41%,进站压力的平均相对误差为3.60%,满足后续优化需求;水力优化结果考虑了沿程站场电价的影响,站内节流阀均保持常开,说明站间没有剩余压力浪费;热力优化结果保证了进站温度均高于原油凝点2~5℃,没有剩余进站温度浪费;总运行费用较优化前降低了12.4%,经济效益明显。研究结果可为原油管道节能运行方案的制定和实施提供理论依据。

With the aging of the pipeline and the deterioration of equipment in the station,the whole energy consumption of crude oil pipeline shows an increasing trend year by year.Based on the decision variables of pump state,furnace state,frequency converter state,pump speed,furnace power,throttle valve pressure drop and so on,the optimization model of energy consumption of crude oil pipeline operation with the objective function of minimizing the total operation cost is established.Combined with the total heat transfer coefficient and hydraulic friction coefficient correction,the optimal operation scheme is solved by dynamic planning algorithm.The results show that the average relative error of inlet temperature and inlet pressure is 3.41%and 3.60%respectively after parameter modification,which can meet the requirements of subsequent optimization.The hydraulic optimization results take into account the influence of electricity price along the station,and the throttle valves in the station are kept normally open,indicating that there is no residual pressure waste between the stations.The thermal optimization results ensure that the inlet temperature is 2~5℃higher than the crude oil freezing point,and no residual inbound temperature is wasted.The total operating cost is reduced by 12.4%compared with that before optimization,and the economic benefit is obvious.The research results can provide theoretical basis for the formulation and implementation of energy conservation operation scheme of crude oil pipelines.