复杂管道系统混输稠油能力研究

Study on the Capacity of Complicated Pipeline System for the Diluted Heavy Oil Transportation

建立含有离心泵和螺杆泵某复杂原油长输管道的工艺计算模型,通过改变稠油的掺柴(稀)比和出站温度,计算该管道系统在不同工况下的输送能力,探究该管道系统混输稠油能力的影响因素。分析计算结果表明:随着输送混合油黏度降低,管道的输送能力出现先增大、后减小、再增大的趋势;对于一定产量的稀原油和稠油,管线的最大输量对应着一个最佳的掺柴比;混合原油的出站温度对管道输送能力的影响不是单调的,随着出站温度的增大,管道的输送能力可能会出现先增大、后下降、再增大的变化趋势;高黏混合稠油处于层流状态时输送更节能。总之,稠油的掺柴(稀)比越大,出站温度越高,该管线输送稠油混合油的能力不一定就越大,而是在不同工况下,在一个最佳掺柴比、掺稀比和最佳的出站温度条件下,输送能力最大。这一结论对于掺稀稠油管道输送工艺的节能降耗有重要的指导意义。

A process calculation model of a complicated crude oil long-distance pipeline with centrifugal pump and screw pump is established.By changing the dilution ratio and station outlet temperature of heavy oil,the transportation capacity of the pipeline system under different working conditions is calculated,and the influencing factors of the mixed heavy oil transportation capacity of the pipeline system are analyzed.The results show that:With the decrease of the viscosity of heavy oil,the pipeline transportation capacity increases at first,then decreases,and increase again.There is an optimal dilution ratio corresponding to the maximum pipeline capacity for a given heavy and lighter crude output.The effect of the outlet temperature of the mixed crude oil on the capacity of the pipeline is not monotonic.For example,with the increase of the station outlet temperatures,the capacity of pipeline transporting diluted heavy oil will ascends first,then descends,and ascends at last.The transportation of high viscosity mixed heavy oil is more energy-efficient when it is in state of laminar flow.In summary,the notion that the pipeline transportation capacity goes up with the heavy oil dilution ratio and the station outlet temperature is one-sided.There are optimal oil dilution ratios and station outlet temperatures corresponding to the maximum pipeline capacity under different conditions,which has an important guiding significance for energy saving and consumption reduction in the transportation of diluted heavy oil.