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In a laboratory or other regulated environment, the need to control the environment is paramount because it determines what can get accomplished in that environment. All sorts of factors from temperature, to dust and other particles, to humidity or the moisture in the air must be controlled and regulated.
To control humidity for items placed in the laboratory, desiccants are used. A desiccant is a substance that can attract and hold water from the surrounding environment, thereby lowering or nearly eliminating humidity. Their use ranges from the most stringent laboratory environment to commonplace uses like those encountered inside food packaging to sustain the crispness of the food.
In a laboratory or clean room environment however, the need for high quality desiccants is great and so dedicated desiccator cabinets and automatic lab desiccators are used widely.
Desiccators are an economical and reliable way to assure dry, dust-free storage and organization of humidity sensitive products such as valuable chemicals or electronics.
In order to ensure the proper storage conditions one needs to select the proper desiccator size, shape and control mechanism best suited to your application, space requirements and items to be stored.
There are four types of desiccators and each has its set of benefits. They are: standard, automatic, gas purge and vacuum.
Standard Desiccator: A standard desiccator unit is operated and monitored manually. As moisture is absorbed from the air in the cabinet, the desiccant will become saturated and then replaced or possibly heated in order to regenerate the desiccant. Standard desiccators provide the flexibility to use any type of desiccant (common forms are silica gel beads and activated charcoal,) providing low cost and great convenience.
Automatic Desiccators: They use electric fans and heaters to continuously regenerate the desiccant which prevents saturation of the desiccant. Humidity is maintained a constant low. These units are programmable and operate on a pre-set schedule. They provide a precise control of humidity, and relieve the need for monitoring them often. Automatic desiccators utilize Process uses silica gel beads that last for thousands of regeneration cycles eliminating the need to replace the desiccation material regularly.
Gas Purge Desiccators: For those seeking to have a fast removal of humidity from an environment, the best choice is a gas purge desiccator. They use a slow and steady flow of inert gas to remove humidity. The gas is usually dry nitrogen which is widely available. Gas purge desiccators create dust free environment and are great for clean rooms.
Vacuum Desiccator: If you have a situation where air and humidity needs to be removed from an environment, your best choice might be a vacuum desiccator. They remove air and moisture from an environment by means of a vacuum pump. These desiccators are also great at creating dust free environments and lend themselves to clean rooms. They can also be used as standard desiccators and utilize standard desiccants.
Each type of desiccator has its advantages and disadvantages and none will provide you with everything you need when you add in low cost as a factor. However, automatic desiccators provide the widest range of benefits in the group. They are lower cost than gas purge desiccators and they work on their own requiring next to no monitoring. Finally, they can be programmed to run at different times and with different humidity levels. So unless you need the highest level of desiccation, they are perhaps the best choice.
