Print this page Desiccant Cooling Technology
A. Bhatia, B.E.
Course Outline
Desiccants cooling technology provides a tool for controlling humidity (moisture) levels for conditioned air spaces. It offers numerous advantages over the more common vapor-compression and absorption units. For example, desiccant systems do not need ozone-depleting refrigerants and are very effective at treating the large humidity loads resulting from ventilation air. Also, they use natural gas, solar thermal energy, or waste heat, thus lowering peak electric demand.
This 4 - hour course provides an overview of how desiccant systems operate and how they can be of benefit. This course is based entirely on the resource guide titled “Desiccant Cooling Technology” developed by U.S. Army Construction Engineering Research Laboratory.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
Learning Objective
At the conclusion of this course, the student will understand the:
- Fundamental concepts of desiccant technology;
- Benefits of dehumidification with desiccants;
- Alternatives to desiccant dehumidification;
- Types of desiccant systems;
- Application of desiccant systems;
- Performance issues related to desiccant systems;
- Maintenance issues related to desiccant systems;
- Method to calculate heat and moisture loads;
- Sizing of desiccant equipment;
- Selection of control system;
- Cost evaluation (Equipment Costs, Installation Costs, Operation Costs and Maintenance Costs); and
- Lifecycle cost analysis in design of desiccant technology.
Intended Audience
This course is applicable to mechanical engineers, HVAC engineers, facility engineers, architects, environmentalists, energy auditors, operations and maintenance personnel, as well as consultants and contractors who construct, build and manage facilities.
Benefit to Attendees
This course will help readers gaining a basic understanding of desiccant technology and its applications.
Course Introduction
A desiccant is a dehumidifying agent which attracts moisture from the atmosphere. It adsorbs and holds particles of water to itself. The use of desiccant cooling and dehumidification systems into existing and new buildings has shown reduced energy costs, better health, greater comfort and increased productivity for building occupants. Recent advances in adsorptive materials, in conjunction with dehumidifier design innovations are making the technology increasingly attractive.
This course will provide an overview of desiccant cooling technology systems.
Course Content
In this course, you are directed to study “Desiccant Cooling Technology” developed by U.S. Army Construction Engineering Research Laboratory. This course content is in the following PDF document:
Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader. If you still experience any difficulty in downloading or opening this file, you may need to close some applications or reboot your computer to free up some memory.
Course Summary
Conventional mechanical compression systems dehumidify air by condensing the water vapor it contains. Unlike conventional technology, desiccant dehumidification offers the immense advantage, among others, of providing precise control over building humidity levels, independently of temperature, particularly at the dew point.
Conventional mechanical compression cooling systems are not designed to handle temperature and humidity loads separately. As a result, oversized compressors are often installed to dehumidify the incoming air. Also, mechanical compression systems are often operated for long cycles and at low temperatures to meet humidity requirements, which reduce their efficiency and require reheating the dry, cold air to achieve some degree of comfort. Both methods are expensive.
Desiccant systems, however, can supplement conventional air conditioners. Working in conjunction, the systems can handle temperature and humidity loads separately and more efficiently. HVAC designers and consultants can thus design systems which will reduce compressor size and eliminate excess chiller capacity.
Quiz
Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.
DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.
