What is Humidity?

Before we tell you about our process of dehumidification, let’s define humidity in itself. Humidity is the amount of water vapor content in the air. Water vapor plays a critical role in maintaining quality and efficiency for products that improve our daily lives – products we consumers trust are manufactured to specification. It is essential for manufacturers in a variety of industries to understand how accurate humidity measurements work, and the role your measurement instrument plays.

The importance of accuracy when measuring humidity is very important. As humidity is often associated with relative humidity, it is imperative that your measurement devices are accurate to the environment around you. Humidity is usually measured by using a hygrometer, a tool that utilizes various materials to gauge and measure a room’s level of water vapor. While no scientific measurement is absolutely true, reaching humidity measurements that are accurate as possible is crucial across all industries. Since water vapor above certain levels can lead to condensation and eventually corrosion or mold, highly accurate humidity measurements are vital to preventing the degradation of everything from wooden construction materials, food products, pharmaceuticals, fuels, paper, electronic components and many other materials. Humidity measurements help maintain optimal environmental conditions for products and prevent costly damage to valuable goods.

What is Dehumidification?

Dehumidification is the process of taking moisture (water vapor) out of the air. Air conditioning systems remove some moisture indirectly in the process of cooling, even though humidity measurements are often not measured or tracked. Separating cooling from dehumidification is the best way to balance thermal comfort, moisture control, and energy use.

Why Choose to Dehumidify?

The benefits of using this technology:

  • Reduces the chance for mold to grow
  • Preserve archival storage
  • Keeps rust from forming on steel and water condensing on cold surfaces
  • Keeps lower dew-point environments comfortable
  • Convey or store hygroscopic materials
  • Removes moisture from event spaces with a lot of water, ice, or people.
  • Makes manufacturing processes and environments optimal

High humidity can make hot days feel even hotter and make indoor spaces >60% RH regularly. Water vapor can penetrate building walls, moving from greater to lesser vapor pressure. Structural damage can be done before symptoms even present themselves. New building structures typically have far less hydroscopic holding capacity meaning greater and faster humidity swings are possible. Measuring space humidity levels is the first step in understanding and controlling your indoor space.

What Equipment is Used for Dehumidification?

Dehumidifiers are different than standard air conditioners. Once moisture is removed on the cold coil, reheat is added so that discharge air re-enters the space temperature-neutral. This reheat often times is waste heat rejected by the condenser coil. The cold coil can either be DX (direct refrigerant expansion) or chilled water. If chilled water is used, waste heat could be in the form of hot water for reheat.

If space conditions mandate lower dew-points, then desiccant dehumidifiers can be deployed. A desiccant dehumidifier is a device where a desiccant material, often times a honeycomb-style rotor is used to produce the dehumidification affect. The process involves exposing the desiccant material to the high relative humidity air stream, allowing it to attract and retain some of the water vapor and then exposing the same desiccants to a lower relative humidity air stream which draws the retained moisture from the desiccant.

How to Select the Proper Dehumidification Equipment

Different dehumidification applications require different equipment. Introducing outside air into an office building or school requires a DOAS (dedicated outdoor air system). Indoor pools require pool dehumidifiers. Battery plants or pneumatic conveying require desiccant dryers.

Moisture loads are calculated for the space, typically in pounds of moisture per hour (lbs/hr). Dehumidifiers are selected to offset the moisture load. The resulting environment should be both temperature and moisture neutral for the required process or people.

Learn more about the Dehumidification products AAP has in stock: