with the water vapor therein resulting in dry airflow 11 b in the embodiment described above in connection with fig1 9 the dry airflow 11 b then passes through the reactivation heating coils 10 of thermal fluid which was previously heated in a microwave heating chamber 35 a so as to heat the dry airflow 11 b the heated dried airflow 11 b would then pass back through the desiccant rotor wheel 7 to deactivate the desiccant material 8 the heated dried airflow 11 b thereby becomes rehydrated forming the heated moisture saturated airflow 11 c however in the alternative embodiment of fig1 the dry airflow 11 b coming from the desiccant rotor wheel 7 does not pass through reactivation heating coils 11 instead it next passes directly into microwave heating chamber 35 a as the desiccant rotor wheel 7 rotates through the microwave heating chamber 35 a the microwave heating chamber 35 a generates microwaves which heat the desiccant material 8 and or the water held in the desiccant material thereby deactivating the desiccant material 8 when the dry airflow 11 b enters the microwave heating chamber 35 a and passes back through the heated and deactivated section of the desiccant rotor wheel 7 it picks up the now released water molecules from the desiccant rotor wheel 7 thereby rehydrating further due to the.