Desiccators are enclosures used for preserving moisture-sensitive items. They provide a safe, economical, dust-free and moisture-free storage environment for a range of devices and products, including micro-electronics, medical devices, and bio-chemicals. There are several types of desiccators. Some are designed to allow an inert gas such as nitrogen to flow through the chamber. Other drying systems are filled with a desiccant that absorbs moisture. Desiccators that use vacuum pressures to prevent the intrusion of moisture are also available. Typically, these sample dryers are also desiccant-filled.
Desiccators differ in terms of performance specifications, physical dimensions, and optional features. Volume or capacity, the number of chambers, and temperature range are the most important performance parameters to consider. Physical dimensions for desiccators include the length, width, and height of the sample dryer. In terms of features, desiccators may provide electrostatic discharge (ESD) protection or block ultraviolet light (UV). Both ESD and UV can damage sensitive materials and equipment. Desiccators with shelves provide individual platforms for samples during drying.
In-line desiccators are used with compressed air systems and low pressure applications. Typically, these sample dryers use molecular sieve or silica gel desiccants to achieve dew points without fogging and corrosion. In-line desiccators for compressed air systems and process gas pipelines are designed to reduce water vapor content under specific working pressures. They are available with different connections and filters, and may be designed for individual applications. In-line desiccators for low pressure systems are often used to protect fuel tanks from moisture and corrosion.
Some vacuum desiccators are made of clear plastic to permit the visual inspection of samples. These large, dome-shaped sample dryers are relatively lightweight, and may be equipped with handles for portability. By removing the lid, users can access ventilated shelves. A molded ring allows the top of the dome to remain inverted on a laboratory bench or other surface. Additional safety features include locator pins that are designed to prevent the top half of the desiccators from sliding away from the bottom half when users lift the desiccator’s dome. Some large vacuum desiccators may also be suitable for non-vacuum applications.