Abstract

The presence of heavy n-alkanes , together with CO₂ and water, affects the accuracy of existing correlations used in equations of state. Moreover, they impact the performance of simulation software, resulting in flawed calculations. In this work, the most used correlations for predicting the properties of heavy n-alkanes are analyzed. Calculations were made using commercial software packages for two compositions of pre-salt reservoirs, and considering the Peng-Robinson and the Soave-Redlich-Kowng equations of state. The properties of the estimated C₂₀₊fraction affected the numerical stability, and the calculated PT diagrams are unexpected. The reasons for the observed pitfalls are discussed.

摘要

重正构烷烃以及CO ₂和水的存在会影响状态方程式中现有相关性的准确性。而且，它们会影响仿真软件的性能，从而导致计算错误。在这项工作中，分析了最常用的预测重正构烷烃特性的相关性。使用商业软件包对两个盐前储层组成进行了计算，并考虑了状态的Peng-Robinson和Soave-Redlich-Kowng方程。估计的C ₂₀₊馏分的性质影响数值稳定性，并且计算出的PT图是出乎意料的。讨论了观察到的陷阱的原因。