When we talk about moisture being in our compressed air... we become mortified, right? The compressed air system can become damaged from corrosion, rust, and scale build-up. Negatively affecting the products and processes that require dry air.
Issues with moisture in compressed air can have a wide range of difficulties for everyone and everything around them. There could be a puddle leaking from the machine causing a slipping hazard in the shop, the moisture can affect the paint job which then can damage the products and byproducts surrounding it. This could also contaminate products or damage other multimillion-dollar equipment nearby. I am sure many of you who are familiar with air compressor equipment have at one time noticed these problems along the way.
Desiccant dryers, however, reduce this havoc-wreaking issue. Desiccant dryers reduce moisture by absorbing and regenerating. Desiccant dryers are used when the compressor is exposed to below-freezing temperatures which happens either from outdoor weather conditions or when passing through refrigerated areas. There are also several other reasons for having a desiccant dryer at your convenience: many materials, processes, and equipment require dry air; dry air means a dew point of -40 degrees Fahrenheit or less.
If there is only a slight portion of the compressed air that needs to dry, there are dryers that are point-of-use dryers that lessen the dew point to more convenient levels after the air is pre-dried with a refrigeration-type dryer. These are basically just small desiccant dryers. The most common and the preferred solution to reducing moisture in the compressed air is going with a twin tower desiccant dryer.
There are a few different types of twin tower desiccant dryers; heatless, heated purge, and heated blower purge. They all use some sort of absorption feature or desiccant bead form. This fills the towers to remove moisture as air passes through them. They operate with one tower drying as the other regenerates on a timer to switch back and forth.
Proper maintenance is required to ensure your twin tower desiccant dryer is in optimal working order and to maximize its useful life.