沥青质是复杂分子物体，与蜡质、芳香烃和饱和烃一起形成原油。沥青质和蜡质在静态储层条件下处于热力学平衡状态。但当热力学条件发生变化时，沥青质可能会沉淀析出。油管中的沥青质沉积一直是一个突出的生产问题，对石油工业有着广泛的经济影响。同时，使用实时工具监测沿井筒的沉积非常困难。
本文针对伊朗油田的一口油井，预测了单相流井筒中的沥青质沉淀区，并计算了三个时间区间内沿油井的沥青质沉积厚度。模拟结果表明，沥青质厚度超过油管半径的50%以上时，流量减少压降增加，油管会堵塞。此外，沿井筒的沉积厚度大致呈斜态正态分布，这可能是流度增加和快速压降的结果。点击英文标题查看原文。
Investigation of Asphaltene Deposition and Precipitation in Production Tubing
Abstract
Asphaltenes are complex molecular entities, which together with resins, aromatic hydrocarbons and saturates forms the crude oil. Asphaltenes and resins are in the thermodynamic equilibrium at static reservoir condition. However, asphaltene can precipitate due to changes in thermodynamic condition. Asphaltene deposition in production tubings has been an outstanding problem with wide economic impact on the oil industry. Meanwhile, the use of real-time tools to monitor depositions along the well is of great difficulty. In this work, the asphaltene precipitation region in a single phase flow wellbore is predicted for an oil well of the Iranian oil field. Then, asphaltene deposition thickness along the well is predicted for three time intervals. The simulation results indicated that asphaltene thickness exceeded more than 50% of tubing radius; therefore, a reduction in flow rate, an increase in pressure drop and tubing blockage are expected. Moreover, it is shown the deposits thickness along the wellbore has approximately a skew normal distribution shape, which could be the result of increases in velocity and excess pressure drop.
Keywords：Asphaltene Precipitation, Asphaltene Deposition, Wellbore, Production Decline
