NON-PURGE PROCESSING ABSORPTION TYPE AIR DRYING SYSTEM AND METHOD FOR PREVENTING HUNTING DEW POINT AND KEEPING UP VERY LOW DEW POINT

摘要

A non-purge processing absorption type air drying system and a method for controlling the same are provided to operate first and second direction conversion valves and a third direction conversion valve for regeneration by a predetermined time difference for preventing a dew point from hunting and keeping a very low dew point of about -100°C, thereby maximizing energy efficiency. A non-purge processing absorption type air drying system includes first and second direction conversion valves(260,270) mounted at lower and upper parts of first and second absorption towers(112,114) respectively for converting flow direction of dehumidifying or regenerating air which is introduced into or discharged from the first and second absorption towers. A third direction conversion valve for generation(190) is connected to the first and second direction conversion valves for circulating air for regeneration. The first direction conversion valve has first and second opening/closing valves(262,264) for injecting the dehumidifying air to the first and second absorption towers, and third and fourth opening/closing valves(266,268) for circulating the air regenerated in the first and second absorption towers. The second direction conversion valve has fifth and sixth opening/closing valves(272,274) for discharging the air dehumidified from the first and second absorption towers to the outside and seventh and eighth opening/closing valves(276,278) for injecting the air for regeneration to the first and second absorption towers. The third direction conversion valve for regeneration has ninth and tenth opening/closing valves(192,194) opened in heating regeneration, and eleventh and twelfth opening/closing valves(196,198) opened in cooling regeneration.