Patent ID: 8449648

Claim:
A method for drying compressed gas comprising: providing a gas dryer with at least two pressure vessels to which compressed gas is supplied and filling the pressure vessels with a desiccant or drying agent; operating the pressure vessels alternately, such that when one pressure vessel is drying compressed gas, the other pressure vessel is being regenerated; guiding a first part of the compressed gas to be dried entering the dryer to a cooler via a regulating line having a regulating valve therein; subsequently drying the cooled first part of the gas in a first of the two pressure vessels, this first pressure vessel acting as a drying pressure vessel; heating a second part of the compressed gas to be dried for use in regenerating the second or regenerating pressure vessel, wherein, when the temperature in the second or regenerating pressure vessel rises above a predetermined upper limit, the regulating valve is gradually moved in the direction of a shut position and, when the temperature in the regenerating pressure vessel drops under a predetermined bottom limit, the regulating valve is gradually moved in the direction of an entirely open position, said movement of the regulating valve enabling the temperature of the first part of the compressed gas to be set at a desired temperature before entering the cooler, and measuring the pressure drop over the regulating valve, and, when the measured pressure drop over the regulating valve drops under a pre-determined minimum threshold value, not opening said regulating valve any further.