Heat of compression dryer system

A gas compressing system comprising:

• a compressor operable to provide a flow of compressed gas and water vapor;
• a first desiccant tower including a first inlet, a first outlet, and a first quantity of desiccant positioned in a first flow path between the first inlet and the first outlet;
• a second desiccant tower including a second inlet, a second outlet, and a second quantity of desiccant positioned in a second flow path between the second inlet and the second outlet;
• a first moisture separator;
• a second moisture separator;
• a dry gas outlet;
• a first set of three and only three valves each movable between an open position and a closed position;
• and
• a second set of three and only three valves each movable between an open position and a closed position, wherein in a first arrangement, each of the valves of the first set of valves is open and each of the valves of the second set of valves is closed and the flow of compressed gas and vapor flows along a flow path from the compressor, through the first desiccant tower to heat and regenerate the first quantity of desiccant, then through the first moisture separator to remove a portion of the water vapor, then through the second desiccant tower to remove additional water vapor, then through the dry gas outlet, and wherein in a second arrangement, each of the valves of the first set of valves is closed and each of the valves of the second set of valves is open and the flow of compressed gas and vapor flows from the compressor, through the second desiccant tower to heat and regenerate the second quantity of desiccant, then through the second moisture separator to remove a portion of the water vapor, then through the first desiccant tower to remove additional water vapor, then through the dry gas outlet.

A method of providing dry compressed gas at a dry gas outlet, the method comprising:

• providing a first desiccant tower and a second desiccant tower, each tower including an inlet and an outlet;
• operating a compressor to compress a quantity of gas to produce a flow of compressed gas and water vapor at a high temperature;
• passing the flow of compressed gas and water vapor along a flow path through the first desiccant tower from the outlet to the inlet to cool the flow of compressed gas and water vapor;
• regenerating desiccant in the first desiccant tower as the flow of compressed gas and water vapor passes therethrough;
• passing the flow of compressed gas and water vapor through the second desiccant tower from the inlet to the outlet, the desiccant in the second desiccant tower adsorbing a portion of the water vapor from the flow of compressed gas and water vapor;
• directing the flow of compressed gas and water vapor from the outlet of the second desiccant tower to the dry gas outlet;
• periodically transitioning a first group of no more than three valves from an open position to a closed position and a second group of no more than three valves from a closed position to an open position to redirect the flow of compressed gas and water vapor from the compressor to the outlet of the second desiccant tower to regenerate desiccant in the second desiccant tower, from the inlet of the second desiccant tower to the inlet of the first desiccant tower to remove a portion of the water vapor from the flow of compressed gas and water vapor, and from the outlet of the first desiccant tower to the dry gas outlet.