When it comes to compressed air systems, moisture can become a problem.

Moisture in compressed air can lead to operational downtime, production losses, and equipment damage. One type of dryer that is particularly effective at removing moisture is a desiccant air dryer.

Certain industries require compressed air systems that produce very clean, very dry air. Although there are many different dryer options, this article solely focuses on the types and uses of desiccant air dryers.

Types of Desiccant Air Dryers

Your unique applications will determine which desiccant air dryer works best for your system. Our team will always help customers choose the best match, but we also wanted to provide you with a resource to reference when you need it.

There are several types of desiccant air dryers that offer unique features and specifications. These include (but are not limited to):

Regenerative Desiccant Air Dryers

A general term for dryers that utilize a desiccant material which attracts and holds moisture. The ‘regenerative’ part comes from the fact that the desiccant is regenerated, or dried out, for reuse. There are various types of regenerative desiccant dryers, including single tower, heatless, heated, and blower purge dryers (listed below). They’re typically used in applications requiring extremely dry air with a pressure dew point as low as -100°F.

Single Tower Desiccant Dryer

Consists of a single tank filled with a desiccant that absorbs the moisture from the compressed air. However, it cannot regenerate the desiccant itself, so manual intervention is required.

Heatless Twin-Tower Desiccant Dryers

Operate on a dual-tower setup. While one tower dries the incoming air, the other regenerates the spent desiccant using a portion of the dried compressed air (purge air).

Heated Desiccant Dryers

Use external heat sources to regenerate the desiccant, reducing the amount of purge air required and improving efficiency.

Heated Blower Purge Desiccant Dryers

Use an external heater and blower to generate hot air for desiccant regeneration, eliminating the need for purge air and making them more energy-efficient.

Manual Change Desiccant Pots

These are simple systems where the desiccant is manually replaced once it’s saturated. They’re typically used in small-scale applications.

The choice of dryer will depend on factors such as the volume of air to be dried, the desired air quality, and the available resources for operation and maintenance.

Uses of Desiccant Air Dryers

Desiccant air dryers employ a moisture-absorbing substance, like silica gel or activated alumina, to extract moisture from compressed air. The air flows through the desiccant bed to undergo a series of chemical reactions, leaving the air dry and clean. It is then regenerated through a process of heating or purging. The regenerated desiccant can then be used again to remove moisture from incoming compressed air, giving it a continuous drying cycle.

Desiccant air dryers are rated by the amount of moisture they can remove in a specific time frame, as well as the size of the compressed air system they can support.

One significant advantage of desiccant air dryers is their ability to produce ultra-dry air. These dryers can remove up to 40% of the moisture present in compressed air. This is especially important in applications such as pharmaceuticals, where contamination could lead to adverse effects.

Other industrial settings where production lines depend on clean, dry compressed air will benefit from using desiccant air dryers. Food and beverage companies, electronics facilities, industrial painters and coaters, healthcare facilities, and laboratories often rely on ultra-clean or ultra-dry air for operations.

Ideal for Outdoor Environments

Desiccant air dryers also excel in outdoor environments that are exposed to extreme temperatures and humidity. Moisture in compressed air can condense in the air lines, causing corrosion and damage to equipment. By removing water vapor from compressed air, they prevent systems from freezing in cold weather conditions that can cause damage to pneumatic tools and machinery. Desiccant air dryers can function in temperatures lower than 35 degrees Fahrenheit and still operate effectively in harsh outdoor settings.

Desiccant air dryers are often used in conjunction with other compressed air dryers like refrigerated dryers and membrane dryers. Refrigerated dryers remove moisture by cooling the compressed air, and a membrane dryer filters out water vapor from compressed air.

However, in some industrial applications, desiccant air dryers are the only option. For example, in the aerospace industry, where air quality is strictly regulated, desiccant air dryers may be the only option to remove water vapor and prevent contamination.


Desiccant air dryers offer unrivaled performance in removing moisture from compressed air. With minimal maintenance, they produce high-quality dry air essential in applications that require moisture-free environments. Their ability to eliminate the threat of oil contamination and function in low temperatures makes them ideal dryer options (or complementary dryer options) for various industries.

At Air Mac, we take the quality, performance, and durability of compressed air very seriously. We know the importance of clean, dry air for our customers. Our selection of desiccant air dryers for compressed air systems is tested through first-hand experience and performance. Every brand we partner with has been hand-selected for their durability and innovation.

With us, customers can trust that they’re investing in durable, effective, and reliable solutions that enhance the lifespan and productivity of their compressed air systems.

Ready to start building your compressed air system? Reach out to us or give us a call at 214-879-1010.