Table 1 The mole fraction and gas properties of natural gases used for modelling.
From: Decoupling and predicting natural gas deviation factor using machine learning methods
Components | Min value (mol%) | Max value (mol%) | Average value (mol%) | Standard deviation | Skewness | Kurtosis |
|---|---|---|---|---|---|---|
\(\hbox {N}_2\) | 0.239 | 2.91 | 1.077 | 0.49 | 1.284 | 4.865 |
\(\hbox {CO}_2\) | 0 | 0.172 | 0.081 | 0.043 | 2.748 | 9.198 |
\(\hbox {CH}_4\) | 93.728 | 73.391 | 89.84 | 2.306 | − 0.861 | 4.18 |
\(\hbox {C}_2\hbox {H}_6\) | 4.512 | 10.4 | 5.955 | 0.971 | 1.118 | 4.063 |
\(\hbox {C}_3\hbox {H}_8\) | 0.772 | 7.253 | 1.668 | 0.621 | 1.25 | 4.916 |
\(\hbox {i-C}_4\) | 0.152 | 2.283 | 0.344 | 0.121 | 1.218 | 3.917 |
\(\hbox {n-C}_4\) | 0.0518 | 2.788 | 0.397 | 0.167 | 0.859 | 3.552 |
\(\hbox {i-C}_5\) | 0.045 | 1.23 | 0.149 | 0.066 | 1.841 | 8.241 |
\(\hbox {n-C}_5\) | 0.022 | 0.779 | 0.113 | 0.056 | 0.913 | 4.755 |
\(\hbox {C}_6\) | 0.017 | 0.574 | 0.12 | 0.084 | 1.895 | 7.675 |
\(\hbox {C}_7\)+ | 0.00562 | 1.293 | 0.312 | 0.338 | 3.818 | 25.07 |
Molecular weight | 17.222 | 23.721 | 18.383 | 0.599 | − 0.357 | 1.543 |
Specific gravity | 0.594 | 0.818 | 0.627 | 0.017 | 0.538 | 2.674 |
Pseudocritical pressure (MPa) | 2.685 | 11.917 | 5.497 | 1.045 | -0.341 | 2.454 |
Pseudocritical temperature (K) | 180.339 | 272.3 | 202.557 | 6.722 | -0.04 | 2.634 |
Temperature (K) | 284.5 | 377.5 | 335.542 | 5.153 | 0.289 | 2.265 |
Pressure (MPa) | 1.6 | 30.35 | 15.7 | 15.245 | − 0.486 | 3.284 |
Z-factor | 0.676 | 1.009 | 0.876 | 0.041 | − 0.546 | 3.917 |
