Refrigeration Type Compressed Air Dryers

The role of air dryers in compressed air systems is crucial, as many industrial tools and processes require moisture-free compressed air to function efficiently.

• During the compression cycle, free water accumulates, leading to corrosion and rust formation within the system. These rust particles travel through the compressed air circuit, causing equipment damage, reduced efficiency, and product contamination.
• Excess moisture in compressed air can promote bacterial growth, which may be absorbed by processed materials, leading to quality degradation, product spoilage, and potential health risks.
• Issues such as rust buildup, equipment failure, solidification of media, and paint defects like bubbling or the “orange peel effect” result in reduced efficiency, material wastage, and increased downtime.

To mitigate these issues and ensure an effective pneumatic system, utilizing air dryers to produce clean, dry compressed air is essential, reducing unnecessary costs and safeguarding the system against damages.

Cooling is one of the most effective methods for eliminating moisture from compressed air. Our Refrigerated Air Dryers use a closed-loop refrigerant circuit to cool compressed air to a precise temperature, allowing moisture to condense and separate. To prevent freezing, the air/gas is cooled to a minimum temperature of +2 to +3°C at an operating pressure of 7 Kgf/cm², ensuring optimal efficiency. These dryers are ideal for applications requiring atmospheric dew points of -20 to -22°C.

Refrigerant dryers feature an air-to-air heat exchanger and an air-to-refrigerant heat exchanger. In the first stage, incoming air is pre-cooled by the outgoing dry air. In the second stage, compressed air is further cooled to approximately 3°C within the Freon circuit, causing moisture to condense. The relative humidity drops below 50% in the reheating phase, preventing free water accumulation and system corrosion. These dryers provide reliable moisture control and are available in water-cooled and air-cooled variants.

At Integrated Engineers & Contractors, we provide Heatless Desiccant Air Dryers, specifically designed for applications that demand exceptionally dry compressed air with a pressure dew point below 0°C. These dryers utilize the natural adsorption process to effectively remove moisture, ensuring a consistent supply of high-quality air for critical industrial operations.

The system operates using two adjacent pressure vessels filled with hygroscopic desiccant beads, which work continuously to remove moisture from compressed air. The drying process involves an automatic cycle where one desiccant tower absorbs moisture while the other regenerates. As the wet air enters the active tower, the desiccant bed traps moisture, delivering ultra-dry air. Meanwhile, a small portion of the dried air is diverted into the second tower for regeneration, allowing the system to maintain consistent performance.

Although heatless adsorption dryers consume 8-10% of compressed air for regeneration, they offer highly efficient moisture control, making them ideal for industries requiring dew points as low as -70°C to -80°C at atmospheric pressure. These dryers ensure the protection of sensitive equipment, prevent system corrosion, and enhance the quality of end products, making them a crucial component in high-precision manufacturing and critical industrial applications.

The dew point is a measure of moisture content in the air, representing the temperature at which moisture begins to condense. The lower the dew point, the drier the air. For instance, air with a dew point of -40°C means that moisture will not condense unless the temperature drops below -40°C. However, achieving lower dew points requires more energy, increasing the operational cost of air dryers. Therefore, selecting the appropriate dew point is essential for maintaining efficiency while ensuring cost-effective operation.

R: refrigerated type, H: heated type, HL: heatless type air dryer, NS: Not Specified.

Quality classes for compressed air according to ISO/DIN 8573/1. Above selection chart is only indicative. For final selection, capacity and ambient conditions are important. For detailed selection, consult Panurgy application engineers.

Following details are required for preparing proposals:

• Air/Gas Flow Rate, Pressure, Temperature, and Compressor Make & Model
• Dew Point Requirement and Application.
• Type of Compressor – Lubricated or Non-Lubricated.
• Application of Compressed Air/Gas.