Based on the Soave–Redlich–Kwong equation of state, empirical correlations for the -values of , , , , and are proposed. Complementarily, the binary interaction coefficients involving the plus fraction, , were optimized by fitting into 131 experimental data from the literature. The criterion to select the form of the empirical correlations was based on the identification of the major dependencies of the equilibrium constants on the system variables (e.g., pressure, temperature, and composition). For most of the experimental data, the saturation pressure calculated via the empirical correlations is in excellent agreement with those reported from the laboratory. The empirical correlations cover a variety of temperatures (128–314°F), pressures (313–6880 psi), and compositions (N₂: 0.0–1.67%; CO₂: 0.0–9.11%; H₂S: 0.0–3.68%; C₁: 5.63–74.18%; C₂: 0.84–12.45%; C₇₊: 10.72–83.2%). The proposed correlations are useful for rapid vapor-liquid equilibrium calculations during the compositional modeling of petroleum reservoirs.

中文翻译：

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原油 K 值的经验相关性

基于 Soave-Redlich-Kwong 状态方程，提出了、、、和的-值的经验相关性。互补地，涉及正分数的二元相互作用系数， 通过拟合来自文献的 131 个实验数据进行了优化。选择经验相关性形式的标准是基于平衡常数对系统变量（例如，压力、温度和成分）的主要依赖关系的识别。对于大多数实验数据，通过经验相关性计算的饱和压力与实验室报告的结果非常吻合。经验相关性涵盖各种温度 (128–314°F)、压力 (313–6880 psi) 和成分 (N ₂ : 0.0–1.67%; CO ₂ : 0.0–9.11%; H ₂ S: 0.0–3.68 %；C ₁：5.63–74.18%；C ₂：0.84–12.45%；C ₇₊: 10.72–83.2%)。所提出的相关性对于石油储层成分建模过程中的快速汽液平衡计算很有用。