凝析油蜡沉积及清管特性

Wax Deposition of Condensate Oil and Its Pigging Characteristics

针对凝析油的管道蜡沉积问题,利用3种凝析油进行了室内蜡沉积环道实验探究。发现相同条件下,沥青质含量相对较低的凝析油的沉积物质量较大,且沉积物中含蜡量较低。其沉积物质量与含蜡量分别约为另外2种凝析油沉积物质量的6倍与0.5倍。分析发现凝析油物性与沥青质含量是影响其沉积物质量及含蜡量的主要因素。此外,综合考虑凝析油物性以及沥青质含量,建立了适用于模拟凝析油在实际管道中结蜡的蜡沉积速率模型,探究了凝析油管道沿线结蜡厚度分布规律,并根据管道最大蜡沉积厚度达到2 mm制定了油品输送的清管周期,管道沿线蜡沉积厚度预测结果与现场实际清管数据吻合良好,最大误差为21.82%。结果表明,凝析油管道依然需要进行定期清管。

The pipeline wax deposition experiment of three kinds of condensate oil was carried out.It is found that the condensate oil with relatively low asphaltene content has higher sediment quantity and lower wax content in the sediment under the same conditions.The deposit quantity and wax content are about 6 times and 0.5 times that of the other two condensate oils,respectively.The physical properties and asphaltene content of condensate oil are the main factors affecting the quantity and wax content of its sediment.Considering the physical properties and asphaltene content of condensate oil,a wax deposition rate model suitable for simulating condensate oil in the actual pipeline is established,the distribution law of wax deposition thickness along the pipeline is explored,and the pigging cycle of condensate oil transportation is formulated according to the maximum wax deposition thickness of the pipeline reaching 2 mm.The predicted wax deposition thickness along the pipeline is in good agreement with the actual pigging data on site,with a maximum error of 21.82%.It indicates that regular pigging is still required for condensate oil pipeline.