If you work in a sensitive industry like food and beverage and medical / pharmaceutical, you'll likely benefit from desiccant dryers. While achieving a low pressure dew point (PDP), these machines remove unwanted moisture that can cause mold and other quality control issues.
Reaching a PDP of -40 °C or lower, these dryers use a hygroscopic material like silica gel to attract and separate water vapor. It's worth pointing out that PDP refers to the amount of moisture in your water system. This measurement is not the same as atmospheric dew point, and strictly refers to compressed air water content.
Depending on your ISO 8573-1 class, you may need to meet strict PDP levels. This point particularly relates to sensitive applications, like mentioned above. In addition to ensuring quality standards are met, air compressor dryers are essential for avoiding corrosion, rust, contaminants, and bacteria within your air system.
Read on below to learn more about how water vapor is formed and the effectiveness of a desiccant compressed air dryer.
When air is compressed, it becomes hotter and its moisture content vaporizes. This water vapor condenses into liquid form as the compressed air starts to cool down. Condensation may then accumulate in the compressor and the air system.
In addition to water, this moisture can contain oil and other contaminants. This point is especially relevant if you're operating an oil-injected air compressor. During the separation process, these contaminants become removed along with the unwanted moisture.
If saturated compressed air is left untreated, you'll likely encounter the issues mentioned above, as well as risk poor results. Both these factors can negatively impact your business.
As mentioned, desiccant dryers use a hygroscopic material to remove moisture from compressed air flow. When operating this equipment, you'll need to regenerate the desiccant and properly maintain filters.
Typically, there are two drums filled with desiccant material. Compressed air moves into the first drum where the adsorbent material removes water vapor. This process causes the desiccant to become saturated.
The second drum is then used to continue drying the compressed air. The first drum’s desiccant is regenerated while this is happening. This arrangement means the dryer can continuously run for peak performance.
Helping manage workflow, you'll find features like a digital control, electronic dew point management system, and optional PDP sensors on new machines. Desiccant dryers also tend to be fairly quiet, and come with on board sensors.
Mark offers a purge regenerated adsorption dryer, also known as a "heatless type dryer." These dryers regenerate desiccant with expanded/purged compressed air.
Typically, a purge dryer requires around 15-20% of the dryer's nominal capacity at 7 bar(e) working pressure. The Mark ADS desiccant dryer has a very low purge consumption, and uses an electronic timer to control phases.
If you use an oil-injected air compressor, it's recommended to use an oil-water separator for your drying system. With environmental regulations becoming stricter, it's important you're disposing of oil correctly.
As previously stated, when water is removed from an air compressor, it usually contains tiny contaminants, including oil.
Since these are usually undetectable to the naked eye, it's important to follow proper protocols. You do not want dirty condensate draining directly onto your floor or in a plastic container.
Not to worry. A proper set up is generally easy to install. Make sure to check your local regulations regarding condensate removal, usually found at recycling centers.
With our compressed air desiccant dryers, you'll benefit from easy installation and high reliability. These machines are well worth the investment for protecting your air compressor equipment while meeting quality standards.
Desiccant dryers are favored for their effectiveness to deliver extremely dry air. If you work in a particularly humid environment, they make an excellent choice. You'll also want to evaluate system capacity and PDP requirements before selecting the right machine.
Of course, our team is happy to help point you in the right direction. Feel free to get in touch today.