Abstract: This drying system dries material with circulating gas or steam of any type. Air is used as the name for the gas. A drying cycle consists of the following basic phases: •Charging of drying material •Heating with circulating air without discharge of air until the air before the air heater has reached desired relative humidity and temperature •Discharge of warm humid air with continued heating of circulating air and intake of outside air or returned dehumidified air. The discharged flow is so controlled that the in the dryer circulating air keeps its desired relative humidity and temperature. •Discharge of the dried material and at the same time cleaning of all the components whose function can be disturbed by dust. •Charging of new material to be dried.