稠油动力黏度预测研究

Prediction of dynamic viscosity of heavy crude oil

在稠油的开采、管输等过程中,动力黏度是一个重要的参数,目前对稠油黏度的估计常采用稠油黏度预测公式进行。然而,由于现有的黏度预测关系式大多基于区域性稠油数据,因此,这些关系式只对特定区域特定组分的稠油才有很高的预测精度。该文采用Hakke RS6000旋转流变仪对中海油采油技术服务公司和渤海油田绥中陆地处理终端的共计3种稠油的动力黏度进行了测量。稠油30oC的黏度范围为:241 mPa·s–5 239 mPa·s,测量温度范围为:20oC–70oC。将Beal、Hossain等和张春明等共计11个黏度预测关系式与该文实验数据进行了对比分析。研究表明,在所研究的关系式中,张春明和Hossain关系式具有最高的预测精度,而Alomair关系式的预测精度最差。同时,结合国内多个学者以及该文的实验数据,推出了一个新的黏度预测关系式。该关系式是温度T和50oC的黏度50μ的函数。它由国内多个区块的稠油黏度数据得来,因此能更好地预测国内稠油的黏度。

Dynamic viscosity is an important parameter both in exploitation and pipeline transportation process of heavy oil. Current estimating of viscosity of heavy oil is often made by using viscosity prediction formulas. However, because most of the existing formulas are empirical equations based on regional data, they are of good prediction precision only for heavy oil with specific components in a particular area. In this paper, viscosities of three heavy oil from Suizhong oil field and China National Offshore Oil Corporation were measured using Hakke RS6000 rotational rheometer. The dynamic viscosity range at 30℃ was： 241 rnPa.s-5239 mPa.s and the temperature range was： 20℃-70℃. Eleven kinds of viscosity calculation models including Beal, Hossain et al. and Zhang Chunming et al. were analyzed comparing with the experimental data. Studies had shown that in all of the eleven models, the prediction accuracy of Zhang Chunming and Hossain was the highest, and Alomair the worst. Besides, a viscosity prediction equation was developed based on the database including the experiment and other scholars＇. This formula is a function of temperature and viscosity at 50℃. Since it is derived from several blocks of heavy oil viscosity data in China, it can better predict the domestic heavy oil viscosity.