成品油管道开泵方案优化MILP模型

MILP model for the optimization of pumping scheme of products pipeline

成品油管道运行过程中沿线各泵站开泵方案的优化对于降低成品油管道的运行能耗具有重要作用。以往针对此问题大多采用动态规划及人工智能算法进行求解,具有一定的局限性,很少从整体上建立混合整数线性规划(MILP)模型并将启停泵时长限制问题考虑到所建模型的约束条件中。在此基于已知的批次调度计划,考虑到启停泵时长限制、沿线节点压力约束、过泵流量约束等约束条件,以泵运行费用与启停泵成本总和最小为目标函数,建立MILP数学模型并采用分支定界算法进行求解。以某实际运行成品油管道的输油计划为例,代入成品油管道开泵方案优化模型并进行求解。结果表明:该模型在较大程度上降低了管道的运行能耗,提高了管道的运行稳定性,符合现场操作工艺。(图3,表2,参24)

The optimization of pumping scheme at each pump station along the products pipelines during the operation plays a vital role in cutting down the energy consumption of products pipelines. The previous studies on this issue mostly make use of dynamic programming and artificial intelligence algorithms to get the solution, which have certain limitations, but rarely establish a mixed integer linear programming model(MILP) and take the time limit of pump start-stop as the constraints of MILP model.In this paper, the MILP mathematical model was established on the basis of the known batch scheduling plan. In this model, the minimum cost of normal operation and start-stop of pumps is taken as the objective function, with the consideration of constraint conditions, e.g. the time limit of pump start-stop, the node pressure along pipelines and the flow rate being pumped. Then, the model was solved by means of branch and bound algorithm. Finally, a case study was carried out on the transportation plan of one in-service products pipeline. It was introduced into the MILP model for optimizing its pumping scheme. And the calculation results indicate that the model can greatly reduce the energy consumption of pipeline operation and improve the stability of pipeline operation to satisfy the requirements of on-site operation process.