Fractional gas recovery below the critical desorption pressure in coal bed methane reservoirs
Input(s)
\(\mathrm{V}_{\mathrm{m}}\): Langmuir (constant)
\(\mathrm{G}_{\mathrm{c}}\): Gas Content at Critical Desorption Pressure (SCF/ton)
b: Langmuir (constant)
P: Pressure of Reservoir (psi)
a: Recovery Exponent (dimensionless)
Output(s)
RF: Recovery Factor (fraction)
Formula(s)
\[
\mathrm{RF}=1-\left(\left(\frac{\mathrm{V}_{\mathrm{m}}}{\mathrm{G}_{\mathrm{c}}}\right) *\left(\frac{\mathrm{b} * \mathrm{P}}{1+\mathrm{b} * \mathrm{P}}\right)\right)^{\mathrm{a}}
\]
Reference(s)
Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 3, Page: 223 .