Using N2 as drying media to replace air partially has the potential of getting a more rapid drying process and a better product quality. The N2 -air mixed gas state parameters were calculated and a humidity-enthalpy chart relating all the relevant variables was developed. Heat transfer coefficient and mass transfer coefficient parameters were predicted according to theoretical calculation. State parameters and mass transfer coefficient for the N2 -air mixed gas were found to increase with increasing N2 content, whereas heat transfer coefficient decreased with an increase in N2 content.