冷热原油交替顺序输送中加热时机的经济比选

Optimal heating ratio of batch pipelining of cold and hot crude oils

冷热原油交替顺序输送是原油输送领域的新工艺,其中确定经济加热方案是工程应用的关键技术之一。建立了冷热油交替输送管道的水力、热力计算模型,用有限容积法和热力特征线法对非稳态热力、水力耦合问题进行求解,并用国内某原油管道现场实测数据对程序进行了检验。基于加热能耗最小,建立了加热方式经济比选的计算模型。数值模拟了不同的加热方案,计算了低凝油不同加热时机的加热能耗。结果表明:对低凝油油尾提前适当时间加热可大大节省加热能耗;加热能耗随加热时机的延长先下降后上升,最佳加热时机约为10%。

Cold oils（ not heated oils） and hot oils（ heated oils） transported alternately in pipelines is a new technology, in the transportation of crude oils. Choosing an economical heating scheme is one of the crucial technologies in the engineering application. An unsteady hydraulic and thermodynamic model describing the heat and fluid flow characteristics of the batch transportation of cold and hot oils was proposed. The governing equations were solved by the combination of a finite volume method and a thermodynamic characteristic method. A code based on the model was developed and verified by the experimental data obtained from a real oil pipeline in China. An optimization model was proposed based on the minimum heating consumption. Numerical calculations were carried out under different heating ratios. The heating consumptions of the low-pourpoint oil tail were calculated under different heating ratios. Economical comparison shows there is an optimal beating ratio for the low-pour-point oil to attain a minimum heating consumption.