Abstract: A process and apparatus for drying of materials such as wood chips or lacquers. A stream of hot gas is provided, the hot gas passes over the material to be dried, the now waste gas is removed from the material to be dried, the volatile substances are deposited from the waste gas and the deposited substances are moved to a collector location. Dust and similar materials can be also bonded during the depositing step. The deposited volatile substances can be removed by intermittent evaporation and/or sublimation and the volatile substances can be collected at a predetermined collector location, or by continuously washing out the volatile substances, or by compressing before cooling down and expanding after cooling down the volatile substances. Removing of deposited volatile substances may be triggered in response to a certain degree of dirtying or soiling and to passing predetermined threshold values of temperature and/or pressure and in accordance with a predetermined time plan, respectively.