Compressed air flows through the pre-filter to remove oil and then enters the on-line Tower 1 through valve (A).
Air moves upward, where the desiccant removes moisture from the air stream. The majority of clean, dry compressed air exits valve (B) and cycles through the after filter to then flows downstream.
During the drying process, a small amount of the clean air exiting valve (B) travels to Tower 2 (shown in regeneration mode) to assist in the regeneration process.
To regenerate Tower 2, valve (C) opens and the tower is depressurized to near atmospheric pressure. The air flowing from valve (B) moves down the tower, removing moisture from the desiccant bed. Once it travels to the bottom of Tower 2, it exits the tower through valve (C) and the exhaust muffler to ambient.
Once Tower 2 is fully regenerated, valve (C) will close, repressurizing Tower 2 to line pressure with the slight airflow coming through valve (B).
Next, valve (D) will open to depressurize Tower 1 and valve (A) will switch (not pictured), directing wet incoming air to Tower 2 for drying while Tower 1 is regenerating the desiccant bed.
This process will repeats continuously every 5 minutes unless the Energy Management System is extending drying time period during low load conditions to a maximum of 30 minutes each cycle. The Energy Management System continually monitors the mid-bed humidity level in the drying tower to save energy by extending the drying cycle (up to 30 minutes).