where N_ CH4 is the molar flow rate of input methane, cp;CH4 the speci-
fic heat capacity of methane, MCH4 the molar mass of methane, and
DTCH4 the difference between the reaction temperature and the
temperature of the preheated methane stream, N_ air the molar flow
rate of input air, cp;air the specific heat capacity of air, Mair the molar
mass of air, and DTair the difference between the reaction tempera-
ture and the temperature of the preheated air stream. The reaction
enthalpy DHr depends on the reaction temperature, and the values
applied in this study are adapted from [32].
The mass flow rate of methane which is combusted to supply
the energy demand in Concept 1 ðm_ comb:;CH4 Þ is calculated according
to the following equation: