The Role of Coal Mechanical Characteristics on Reservoir Permeability Evolution and Its Effects on CO₂ Sequestration and Enhanced Coalbed Methane Recovery

Table 3

Key parameters for ECBM recovery.

Parameter	Value	Remake	Parameter	Value	Remake
Initial permeability (, mD)	0.5	—	Elastic modulus of coal seam (, GPa)	2.7	[42]
Porosity of fracture (, %)	0.4	—	Poisson’s ratio of coal ()	0.35	[42]
Dynamic viscosity of CO2 (, Pa s)		[52]	Langmuir pressure constant of CO2 (, MPa)	1.38	[42]
Dynamic viscosity of N2 (, Pa s)		[52]	Langmuir volume constant of CO2 (, m^3/kg)	0.0447	[42]
Langmuir-type strain coefficient of CO2 ()	0.0237	[42]	Langmuir pressure constant of N2 (, MPa)	2.61	[43]
Langmuir-type strain coefficient of N2 ()	0.0058	[43]	Langmuir volume constant of N2 (, m^3/kg)	0.0146	[43]
Adsorption time of CO2 (, d)	4.34	[43]	Langmuir pressure constant of CH4 (, MPa)	2.07	[42]
Adsorption time of N2 (, d)	4.34	[43]	Langmuir volume constant of CH4 (, m^3/kg)	0.0256	[42]
Thermal conductivity of CO2 (, W/(m K))	0.0137	[42]	Isosteric heat of CO2 adsorption (, kJ/Mol)	19.2	[42]
Thermal conductivity of N2 (, W/(m K))	0.0262	[43]	Isosteric heat of N2 adsorption (, kJ/Mol)	12.8	[43]
Specific heat capacity of CO2 (, J/(kg K))	844	[42]	Specific heat capacity of N2 (, J/(kg K))	1040	[43]
Initial CH4 pressure in fracture (, MPa)	5	[54]	Initial CH4 pressure in matrix (, MPa)	5	[54]
Initial CO2 pressure in fracture (, MPa)	6	—	Initial CO2 pressure in matrix (, MPa)	6	—
Initial N2 pressure in fracture (, MPa)	6	—	Initial N2 pressure in matrix (, MPa)	6	—