Humid environments not only compromise living comfort but also pose challenges for industrial production, warehousing, 

and storage. Among various dehumidification technologies, desiccant dehumidifiers stand out for their unique operating 

principle, delivering exceptional performance under high-humidity and low-temperature conditions, making them the 

preferred choice for many professional applications. This article delves into its core structure and operating principles, 

comparing it with traditional compressor-based dehumidifiers to provide readers with a fundamental understanding of 

this technology.

I. Core Structure Analysis

The key components of a desiccant wheel dehumidifier include the adsorption wheel, regeneration system, air handling 

system, and control system.

• The adsorption wheel is typically constructed from a special composite material with a honeycomb structure, coated

  with high-performance adsorbent materials (such as silica gel or molecular sieves). This design significantly increases

  the surface area exposed to humid air, enhancing moisture adsorption efficiency. The wheel is divided into processing

  and regeneration zones, continuously cycling through adsorption and regeneration through slow rotation.

• The regeneration system primarily includes heating devices (such as electric heaters, steam heaters, or waste heat

  recovery units) and a regeneration fan. Its function is to heat the moisture-adsorbed section of the wheel, causing

  the moisture to desorb and restoring the wheel's drying capacity.

• The air handling system directs humid air through the treatment zone and delivers dried air to the target space.

  Simultaneously, it guides regenerated air through the heating process in the regeneration zone, carrying off desorbed

  moisture for outdoor discharge.

II. Detailed Working Principle

The desiccant wheel dehumidification process is a continuous cycle of physical adsorption and thermal regeneration, 

divided into two synchronized key stages:

• Dehumidification (Adsorption) Process: Moist air is drawn by a fan through the wheel's treatment zone. Water molecules

  in the air are firmly captured by the adsorbent material within the wheel, and the dried air is then delivered to the space

  requiring dehumidification. This process does not require cooling the air below its dew point, thus preventing condensation

  and avoiding frost formation in low-temperature environments.

• Regeneration (Desorption) Process: Simultaneously, a separate stream of external air (regenerative air) is heated to a high

  temperature (typically 100-140°C) via a heater. This hot air passes through the wheel's regeneration zone, raising the

  temperature of the adsorbent material within. The captured moisture gains energy and desorbs, being carried out of the

  unit with the hot air. The regenerated section of the wheel partially restores its dry state. As the wheel rotates slowly

  (typically several to over ten revolutions per hour), it re-enters the processing zone to begin a new dehumidification cycle.

This continuous, stable rotational cycle enables the sustained output of dry air, achieving highly efficient and consistent 

dehumidification performance.

III. Core Differences from Traditional Compressor-Based Dehumidifiers

Compared to the more prevalent compressor-based (condensation-type) dehumidifiers, wheel-type dehumidifiers operate 

on fundamentally different principles:

• Principle: Compressor dehumidifiers cool air below its dew point via refrigerant cycles, condensing water vapor into liquid

  for drainage. This is essentially condensation dehumidification. Wheel-type units utilize the physical properties of adsorbent

  materials for adsorption dehumidification.

• Temperature Adaptability: Compressor-based units experience a sharp decline in efficiency in low-temperature environments

  (typically below 15°C), with evaporator surfaces prone to frost buildup requiring frequent defrosting—or even becoming

  inoperable. Desiccant dehumidifiers, requiring no air cooling, maintain stable and efficient dehumidification even in sub-zero

  conditions. This represents one of their most significant advantages.

• Humidity Control Capability: Compressor-based units can reduce humidity to approximately 50% RH at ambient temperatures.

  In contrast, desiccant dehumidifiers leverage their potent adsorption capacity to achieve extremely low humidity levels

  (e.g., 10% RH or lower), meeting stringent low-humidity requirements in precision manufacturing, lithium battery production,

  pharmaceutical storage, and similar demanding applications.

• Energy Form: Refrigerant-based units primarily consume electricity for compressor refrigeration. Desiccant dehumidifiers' main

  energy expenditure lies in regeneration heating, where heat sources can flexibly utilize electricity, steam, gas, or industrial waste

  heat. In settings with waste heat recovery capabilities, this significantly reduces operating costs.

IV. Technical Advantage Analysis

Based on the above principles and differences, desiccant wheel dehumidifiers demonstrate multiple technical advantages:

• Superior Low-Temperature Dehumidification Performance: Operates independently of ambient temperature, delivering

  unmatched performance in low-temperature, high-humidity environments like cold storage facilities and workshops in

  frigid regions, continuously supplying dry air.

• Deep Dehumidification Capability: Achieves extremely low humidity control, meeting stringent requirements for high-end

  industrial production and specialized material preservation.

• Strong Environmental Adaptability: No liquid condensate is produced during operation, preventing bacterial growth and

  drainage issues. Additionally, minimal impact on air sensible heat minimizes noticeable temperature fluctuations in treated spaces.

• Stable and Reliable Operation: Features a relatively simple structure without high-pressure moving parts like compressors,

  ensuring easy maintenance, extended service life, and high reliability in harsh industrial environments.

• Flexible Energy Utilization: Supports diverse regeneration heat sources, facilitating integration with factory waste heat,

  solar energy systems, and others to enhance overall energy efficiency.

Conclusion

The desiccant wheel dehumidifier establishes an efficient, stable, and adaptable dehumidification method through its unique 

adsorption wheel and regeneration system. It overcomes the temperature limitations of traditional compressor-based technologies, 

enabling efficient operation and deep dehumidification in low-temperature environments. This makes it indispensable in industrial 

production, warehousing and logistics, laboratories, swimming pools, and other sectors with stringent or specialized humidity control 

requirements. Understanding its core principles and technical advantages empowers us to select and apply dehumidification equipment 

more scientifically, thereby effectively resolving diverse moisture-related challenges.