Absorption type air drying system and method of performing heating regeneration of the same

Abstract

This invention relates to an absorption type air drying system which can maximize energy efficiency, and to a method of controlling the same. This absorption type air drying system includes first and second adsorption towers, first diverter valves provided below the first and second adsorption towers to change the direction of transport of dehumidification air and regeneration air and including first to fourth on-off valves, second diverter valves provided above the adsorption towers to change the direction of transport of dehumidification air and regeneration air and including fifth to eighth on-off valves, and regeneration diverter valves connected to the first and second diverter valves to circulate the regeneration air and including ninth and tenth on-off valves which are opened upon heating regeneration, and eleventh and twelfth on-off valves which are opened upon cooling regeneration.

What is claimed is: 
     
         1 . An absorption type air drying system, comprising:
 first and second adsorption towers;   first diverter valves provided below the first and second adsorption towers so as to change a direction of transport of dehumidification air and regeneration air which are fed into or discharged from the first and second adsorption towers;   second diverter valves provided above the first and second adsorption towers so as to change the direction of transport of dehumidification air and regeneration air which are fed into or discharged from the first and second adsorption towers; and   regeneration diverter valves connected to the first and second diverter valves so as to circulate the regeneration air,   wherein the first diverter valves include first and second on-off valves for feeding the dehumidification air into the first and second adsorption towers, and third and fourth on-off valves for circulating air regenerated in the first and second adsorption towers,   the second diverter valves include fifth and sixth on-off valves for discharging air dehumidified in the first and second adsorption towers to outside, and seventh and eighth on-off valves for feeding the regeneration air into the first and second adsorption towers, and   the regeneration diverter valves include ninth and tenth on-off valves which are opened upon heating regeneration, and eleventh and twelfth on-off valves which are opened upon cooling regeneration.   
     
     
         2 . The absorption type air drying system of  claim 1 , wherein the first to twelfth on-off valves have a two-way valve structure. 
     
     
         3 . The absorption type air drying system of  claim 1 , wherein the first adsorption tower performs a dehumidification process, and the second adsorption tower performs a regeneration process. 
     
     
         4 . The absorption type air drying system of  claim 1 , wherein the first adsorption tower performs a regeneration process, and the second adsorption tower performs a dehumidification process. 
     
     
         5 . A method of performing heating regeneration of an absorption type air drying system comprising a compressor for compressing external wet air, first and second adsorption towers, first diverter valves provided below the first and second adsorption towers to change a direction of transport of dehumidification air and regeneration air, second diverter valves provided above the first and second adsorption towers to change the direction of transport of dehumidification air and regeneration air, regeneration diverter valves connected to the first and second diverter valves to circulate the regeneration air to the first and second adsorption towers, a heater provided on a pipe communicating with upper portions of the first and second adsorption towers, and a controller, the method comprising:
 1) circulating the regeneration air to either of the first and second adsorption towers by the regeneration diverter valves;   2) selectively operating the heater depending on an internal temperature of the first or second adsorption tower; and   3) passing the regeneration air through the first or second adsorption tower to perform heating regeneration of the first or second adsorption tower,   wherein the selectively operating the heater in 2) comprises:   2-1) detecting the internal temperature of the first or second adsorption tower wherein the regeneration process is performed;   2-2) determining whether the detected temperature corresponds to a temperature of compression heat of the compressor; and   2-3) operating the heater when the internal temperature of the first or second adsorption tower corresponds to the temperature of compression heat of the compressor, so that the regeneration air is heated to a regeneration temperature.   
     
     
         6 . The method of  claim 5 , wherein in 2-1), the temperature of a lower portion of the first or second adsorption tower is detected by means of a temperature sensor. 
     
     
         7 . The method of  claim 6 , wherein in 2-2), the temperature of compression heat of the compressor is 90˜150° C. 
     
     
         8 . The method of  claim 6 , wherein in 2-3), the regeneration temperature is 170˜250° C. 
     
     
         9 . An absorption type air drying system, comprising:
 a dehumidification tank including a first dehumidification bed, a second dehumidification bed and a third dehumidification bed, which are partitioned by at least one barrier;   a compressor for compressing external wet air;   a cooler for cooling the wet air discharged from the compressor;   a wet air supplier provided downstream of the cooler so as to supply the wet air to the dehumidification tank;   a wet air chamber connected above the dehumidification tank via a pipe;   a dry air chamber connected below the dehumidification tank via a pipe;   a cold compressed air regeneration chamber connected between the dehumidification tank and the wet air chamber via a pipe;   a hot compressed air regeneration chamber connected between the dehumidification tank and the dry air chamber via a pipe;   a dehumidification line connected between the compressor and the wet air chamber;   a hot compressed air regeneration line, which is divided from the dehumidification line provided between the compressor and the cooler and is connected to the hot compressed air regeneration chamber;   a cold compressed air regeneration line, which is divided from a dehumidification line provided between the cooler and the wet air supplier and is connected to the cold compressed air regeneration chamber;   first and second diverter valves respectively provided on the hot compressed air regeneration line and the cold compressed air regeneration line so as to change flow of regeneration air;   a connection pipe connected between the first and second diverter valves; and   a separator communicating with the connection pipe and including an air outlet for discharging air connected to the wet air supplier via a circulation pipe,   wherein a plurality of inlet pipes extends from the wet air chamber, and the plurality of inlet pipes is connected to communicate with the first to third dehumidification beds of the dehumidification tank via a plurality of upper air control valves,   the cold compressed air regeneration chamber is connected to communicate with the first to third dehumidification beds of the dehumidification tank via a plurality of communication pipes,   the plurality of upper air control valves is provided between the inlet pipes and the communication pipes, and the upper air control valves have a three-way valve structure with first, second and third ports, and the first and second ports are provided to communicate with the communication pipes and the third ports are provided to communicate with the inlet pipes,   a plurality of outlet pipes extends from the dry air chamber, and the plurality of outlet pipes is connected to communicate with the first to third dehumidification beds of the dehumidification tank via a plurality of lower air control valves,   the hot compressed air regeneration chamber is connected to communicate with the first to third dehumidification beds of the dehumidification tank via a plurality of communication pipes, and   the plurality of lower air control valves is provided between the outlet pipes and the communication pipes, and the lower air control valves have a three-way valve structure with first, second and third ports, and the first and second ports are provided to communicate with the communication pipes and the third ports are provided to communicate with the outlet pipes.   
     
     
         10 . The absorption type air drying system of  claim 9 , wherein the wet air supplier includes an ejector having a nozzle, and the nozzle of the ejector is connected to the circulation pipe of the separator. 
     
     
         11 . The absorption type air drying system of  claim 9 , wherein the wet air supplier includes a flow control valve, and the circulation pipe of the separator is connected downstream of the flow control valve of the dehumidification line. 
     
     
         12 . The absorption type air drying system of  claim 9 , wherein the hot compressed air regeneration line is provided with a heater.