Method and apparatus for controlling moisture

摘要

A method and system for controlling moisture content of a gaseous flow (500). A pair of desiccant contact structures (100, 200) each provided with a process (102, 202) adapted to pass through a process gaseous stream to altering the moisture content of the gaseous stream. Each desiccant contact structure also has a regeneration side (101, 201) adapted to pass through a regeneration gaseous stream for altering the moisture content of a desiccant in the contact structure. The process side (102) of a first desiccant contact structure (100) is fluidly connected to the regeneration side (201) of a second desiccant contact structure (200) via a first closed recirculation loop (300). In an alternative embodiment a second closed recirculation loop (400) may also be provided on the regeneration side (101) of the first desiccant contact structure (100). Gaseous flow (500) is then provided to the process side (202) of the second desiccant contact structure (200) to thereby control its moisture. The closed recirculation loops provide significant energy saving over the conventional systems. In other embodiments multiple desiccant wheels can be provided on the high or low temperature sides.