Reservoir EngineeringUnconventional Reservoirs
Langmuir Desorbable Gas Content Between Pressures Formula
Langmuir Desorbable Gas Content Between Pressures calculates desorbable gas content for unconventional reservoirs workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (V_L, P_i, P_f, P_L) are known and the assumptions behind the cited unconventional reservoirs relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, G_des equals 95.238095 SCF/ton.
V_LSCF/ton
800
P_ipsi
1000
P_fpsi
500
P_Lpsi
200
Inputs
V_L
SCF/tonLangmuir Volume
P_i
psiInitial Reservoir Pressure
P_f
psiFinal Reservoir Pressure
P_L
psiLangmuir Pressure
Outputs
G_des
SCF/ton
Desorbable Gas Content
V_L
SCF/ton
Langmuir Volume
P_i
display onlypsi
Initial Reservoir Pressure
P_f
display onlypsi
Final Reservoir Pressure
P_L
display onlypsi
Langmuir Pressure
Source and review
reviewedDerived from Ahmed and McKinney's Langmuir adsorption relationship for coalbed methane.
Source