Abstract: Characterization is essential to modeling ill-defined systems like crude oil. Based on reasonable physical postulates and some certain mathematical model, a successful characterization model can give a reasonable description of the ill-defined parts of the crude oil,thus satisfying the requirement of reservoir phase calculation and reservoir simulation. with the present characterization methods, crude is taken as a homogeneous phase which is contrary to the fact that the crude is essentially a kind of colloid with resin and asphaltene (solid phase) suspending in it. This results in a big deviation when the present methods are applied to some of heavy oil. A modified characterization method is proposed by considering the solid (resin and asphaltene)-liquid (homogeneous oil phase) equilibrium existing in crude. Calculation of several live oil properties with the modified method was made and much better results are obtained in comparison with the present ones.

Key words: solid-liquid equilibrium, characterizing crude, asphaltene precipitation, method

摘要： 原油的特征化是利用一定的物理和教学模型,对复杂的原油体系进行简化描述,从而实现对其进行较为合理的解释,以满足油藏物性计算和油藏数值模拟等模型化工作的需要。坦现有原油特征化方法忽视了原油中有胶质、沥青质固体胶束相存在的事实,将原油以单一液相进行处理,从而导致在对于重质原油的相态计算及研究原油中沥青质、胶质等重有机质沉淀问题时,存在与原油的实际物理性质相矛盾、且计算结果与实验结果相比也存在较大的误差。基于原油中存在重有机质团相的物理事实出发,对现有的原油特征化方法进行了改进。在物理机理上,使现有特征化方法更加符合实际情况。并利用提出的方法,对几种较重原油的油藏物性进行了模拟计算,通过与现有特征化方法计算结果的比较可以看出,改进后的特征化方法所得到的计算结果准确性有较大提高。

关键词: 固液平衡, 原油特征化, 沥青质沉淀, 方法, 改进