Best air dryer for air compressor – how do I choose & select?

Best air dryer for air compressor is not the most expensive. Here we will bring you to know how to choose the compressed air dryer. We know the range of compressed air applications are wide. It can be used in various industries, such as laser cutting, electrostatic spraying, sandblasting, pneumatic tools, etc. But what we need is clean and dry air. Condensation can damage our equipment if not removed. It will also degrade product quality. So we need to use the air compressor dryer.

What is the best air dryer for air compressor?

Different industries have different requirements for compressed air quality. So we need select the air dryer according to the specific requirements. Relative humidity (RH) and pressure dew point (PDP) are indicators to measure the dryness of compressed air.

The lower the relative humidity (RH) of compressed air, the less water vapor it contains. That is, the air is drier. So the lower the relative humidity (RH), the better.

The water vapor content in the air usually does not reach the saturation state of the maximum water content. The percentage of actual and maximum content below saturation is the relative humidity (RH). Knowing the dew point and relative humidity, the water vapor content can be calculated. E.g:

Saturation content at 25°C dew point (DP) = 22.830g/m. Relative humidity (RH) 70%. Then 1m content =1X22.83X70% = 15.981g;

Saturation content at 35°C dew point (DP) = 39.286g/m. Relative humidity (RH) 100%. Then 1m content=1X39.286X100%=39.286g;

(1) The types of air dryer for compressor

The standard for measuring the moisture content of compressed air is ISO8573-1:2010. It stipulates six grades of compressed air pressure dew point (PDP) from -70°C to 10°C. The lower the pressure dew point (PDP) number, the higher the compressed air quality requirements. That is, the compressed air is drier.

The best air dryer for air compressor choice depends on the application requirement. Air compressor dryer has different drying principles and technologies. Usually, it contains a refrigerated air dryer and an adsorption air dryer. Some manufacturers also produce membrane dryers. Water will change from liquid to solid at temperatures below 0°C. That is, freezing. Therefore, the refrigerant air dryer cannot achieve a drying effect below 0°C. At this time, it is necessary to choose a desiccant air dryer or a membrane dryer.

(2) Refrigerated air dryer for air compressor

It cools the compressed air. And reduce the pressure dew point to 2 ~ 10 ℃. The lower the dew point, the better the performance of the refrigeration dryer. Finally, the water vapor in the air condenses into liquid water. And separate out. Thereby it achieves the purpose of drying compressed air.

So what is the best-refrigerated air dryer for air compressor? In fact, refrigerant air dryer also include many types. For example, it has a normal temperature type and high inlet temperature type. Besides, there are different materials available. In addition, there are also different pressures available. These are low-pressure air dryer and high-pressure refrigerant air dryer. It also includes an air-cooled refrigerant dryer and a water-cooled refrigeration dryer.

(3) Desiccant air dryer for air compressor

There are different adsorption regeneration methods. So desiccant air dryer for air compressor include the following types. That is, heatless, heated (micro heat), blower purge, and compression heat (HOC) regenerative air dryer. Different regeneration air dryers, different energy consumption. Similarly, the desiccant dryer can also be made of different materials. In addition, we also produce a kind of compact-size desiccant dryer. That is a modular adsorption air dryer. It has a smaller size and lighter weight. So what is the best desiccant air dryer for air compressor? We need to select it according to our different requirements.

How to select the best air dryer for air compressor?

There are many factors to consider when choosing a dryer. Basic parameters are prerequisites. Pressure dew point is an important performance requirement. Similarly, different industries also have different material requirements.

(1) Basic dryer parameters

Firstly, the total airflow of the compressed air dryers must be clear. If you already have the screw air compressor, you can directly inform its power. Then we can know what size dryer to offer. Of course, the air capacity of the dryer is generally slightly larger than that of the air compressor.

If you don’t have an air compressor, you need to calculate the total air consumption of all your equipment. Then we can match you with the right dryer.

Secondly, we must know the exhaust air pressure. It’s also important for us to choose the best air dryer for air compressor. Normally the pressure 7~10bar is suitable for most industries. However some industries have different pressure requirements.

For example, the textile industry requires low-pressure refrigerated air dryer. The bottle-blowing industry requires a medium-pressure refrigerant dryer (25~40bar). There are also some industries that require high-pressure refrigeration dryers and desiccant dryers. Different pressures, different materials, and specifications. Therefore, the price of the dryer is also different.

Thirdly, it must know the pressure dew point. If your industry does not require high moisture content, you only need a refrigerated dryer. Its pressure dew point is 3~10℃. Of course, some customers strictly require a dew point of 3~5°C. We can also customize it. But if you need lower dew point, please confirm that it’s -20℃, -40℃ or -70℃. The lower the dew point, the more expensive the dryer.

In addition, it also needs to specify the intake air temperature. Because there are different types of refrigerant dryers. Normal-temperature type refrigerated dryer is not applicable in high-temperature areas. Besides, the intake temperature of the desiccant air dryer should not be too high. Otherwise, it needs to add a refrigeration dryer or cooler. The HOC-type absorption dryer must require the intake air temperature to reach 120°C.

(2) Energy saving requirements

Energy efficiency is also an important factor in choosing the best air dryer for air compressor. Because it affects the our operation cost.

Firstly, there are two types of energy-saving products for refrigerant air dryers. That is cycling and VSD refrigerated air dryer. Usually, we use a non-cycling type refrigeration dryer. It has no energy-saving effect. But the cycling refrigerant dryer contains a water accumulator. Therefore, it can realize energy savings. In addition, the VSD air dryer can adjust the refrigerant compressor. Therefore, it can also achieve energy savings.

Secondly, different desiccant air dryers, and different regeneration air consumption. So the energy consumption is different. A heatless air dryer will consume lots of regeneration air. The heated desiccant dryer consumes less regeneration air. Blower purge and HOC type dryers consume much less air. And zero air-loss desiccant dryer is the most energy-saving.

(3) Compressed air dryer material

Some industries have special requirements for dryer materials. For example, the medical & food industry have high requirements on air quality. Therefore, it also requires that the dryer must be stainless steel material. The marine industry also requires that the dryer must be stainless steel. For example, it requires SS316 or SS304+ special anti-corrosion coating. Of course, the higher the material requirements, the higher the price. So we must confirm the dryer material. Then we can choose the best air dryer for air compressor.