C243 – TP-15 2007 Vapour Pressure Calculation for NGLs
Description
This calculates the equilibrium vapour pressure of natural gas liquids based on their relative density and process temperature.
References
API MPMS 11.2.5/GPA Technical Publication TP-15 – A Simplified Vapor Pressure Correlation for Commercial NGLs September 2007
Kelton calculation reference C243
FLOCALC calculation reference F058
KIMS calculation reference K198
Options
Method
- New
- Modified
Choose option based on which method you wish to employ. The modified method requires the vapour pressure at 100°F as an input.
Constants
Gas coefficients
C = 443°F
D = 543°F
Table 1: Parameters for vapour pressure correlation
| Range | A0 | A1 | A2 | B0 | B1 | B2 |
|---|---|---|---|---|---|---|
| 0.35 ≤ γ60 < 0.45 | 17.5297 | -24.604 | 24.373 | -6567.6 | 19322 | -24693.3 |
| 0.45 ≤ γ60 < 0.49 | 7.9907 | 7.562 | 0 | 1895.5 | -10596.9 | 0 |
| 0.49 ≤ γ60 < 0.51 | -6.4747 | 37.083 | 0 | 12038 | -31296.5 | 0 |
| 0.51 ≤ γ60 < 0.56 | 11.5454 | 1.749 | 0 | 1378.8 | -10396.1 | 0 |
| 0.56 ≤ γ60 < 0.585 | 6.4827 | 10.79 | 0 | 3721.5 | -14579.5 | 0 |
| 0.585 ≤ γ60 < 0.625 | 6.5412 | 10.69 | 0 | 6514.5 | -19353.9 | 0 |
| 0.625 ≤ γ60 ≤ 0.676 | 20.8537 | -12.21 | 0 | -6765.6 | 1894.3 | 0 |
Calculation
Vapour Pressure
The equilibrium vapour pressure is calculated by:
New Method
Modified Method
| Where | ||
|---|---|---|
| T | = | Process temperature |
| P100 | = | Vapour pressure at 100°F |
| A | = | Coefficient based on Table 1 “Ax” parameters and relative density |
| B | = | Coefficient based on Table 1 “Bx” parameters and relative density |
| C | = | Gas coefficient C |