Designing Environmental Chambers: The Role of Desiccant Dehumidification
- Summer Neal
- Mar 25
- 3 min read
Environmental chambers are essential in industries such as pharmaceuticals, aerospace, electronics, and material testing, where precise control of temperature and humidity is necessary. Achieving these controlled conditions requires a well-designed system that effectively manages moisture levels, as excess humidity can compromise test results, damage sensitive components, or alter material properties. Desiccant dehumidification plays a crucial role in optimizing environmental chambers, ensuring stable and repeatable conditions for a variety of applications.
Humidity influences material behavior, corrosion rates, chemical reactions, and overall system stability. Without effective moisture management, an environmental chamber may fail to deliver consistent conditions, leading to inaccurate test results or product failures. A desiccant dehumidifier is particularly beneficial in chambers requiring ultra-low humidity levels or precise control over moisture content.
Unlike refrigeration-based dehumidification, which condenses moisture out of the air, desiccant dehumidifiers use hygroscopic materials (Innovative Air Technologies utilizes silica gel) to adsorb water vapor directly, allowing for precise control even at low dew points. This makes them particularly effective for applications where maintaining strict environmental conditions is critical.
Designing an Optimal Environmental Chamber with Desiccant Dehumidification
An optimal environmental chamber design integrates desiccant dehumidification into a comprehensive climate control system.
The key components include:
1. Precise Temperature and Humidity Control
Desiccant dehumidifiers provide superior control over humidity, especially in low-temperature environments where traditional cooling-based dehumidifiers struggle. By selecting the appropriate desiccant wheel configuration and regeneration process, the system can maintain consistent humidity levels.
Example: A pharmaceutical stability testing chamber may require a temperature of 77°F and a relative humidity of 30% RH to simulate long-term storage conditions. Incoming ambient air at 95°F and 60% RH carries an absolute humidity of 126 grains per pound of dry air (gr/lb.). A desiccant dehumidifier can reduce the moisture content to 56 gr/lb., achieving the target humidity while maintaining precise environmental stability.
2. Pre- and Post-Treatment of Air
Pre-Cooling: In high-temperature environments, pre-cooling the air before it enters the desiccant wheel reduces the energy load on the system, improving efficiency.
Post-Cooling: Since desiccant dehumidification inherently increases air temperature, a post-cooling coil can be used to bring the air back to the desired setpoint.
Post-Heating: In applications requiring ultra-low humidity, post-heating prevents condensation and ensures uniform air distribution.
3. Controlling Dew Point for Low-Humidity Applications
Certain applications demand extremely low dew points that only desiccant dehumidifiers can achieve.
Example: An aerospace component testing chamber might need a dew point of -40°F to prevent moisture-related failures in electronic components. If the incoming air has a dew point of 50°F, a desiccant system can efficiently bring it down to the required level, ensuring moisture-sensitive materials remain unaffected.
4. Airflow and Uniformity Considerations
Proper air distribution prevents localized humidity or temperature variations that can skew test results. A desiccant dehumidifier integrated with a well-designed airflow system ensures uniform conditions throughout the chamber, regardless of load variations or external influences.
Case Study:
Controlled Environmental Systems designed and built an environmental chamber for Sport Product Testing in Alberta, Canada, large enough to house both a Thermal Manikin and a treadmill, along with the necessary systems for temperature, humidity & oxygen control. The Innovative Air Technologies Compact Series desiccant dehumidifier (Model# IAT-300REC) was crucial in achieving humidity control, a critical factor for both product testing and athletic training. The dehumidifier was equipped with MERV 8 filters and stainless-steel construction, ensuring efficient and reliable moisture control.
Read the full case study HERE
Creating an optimal environmental chamber requires precise control over temperature and humidity, making desiccant dehumidification an indispensable solution. Whether for pharmaceutical stability testing, aerospace component verification, or battery performance evaluation, integrating a desiccant dehumidifier ensures stable, repeatable conditions that enhance the reliability of testing and manufacturing processes.
By leveraging advanced moisture control strategies, industries can achieve the stringent environmental conditions necessary for research, development, and quality assurance, ultimately improving product performance and reliability.
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