What is structured desiccant?

To answer that question, we first have to understand what desiccant is. Although most people may be unfamiliar with the term, it is very likely they have come across this drying agent in their daily lives. Desiccant can most often be found in the form of those small pouches filled with tiny beads that keep packaged products dry. Various materials can serve as desiccant but silica is most commonly used – frequently as a gel. That is the substance contained in the small desiccant packets which are added to food, apparel and electronics packaging. This gel is able to absorb and store moisture in millions of miniscule pores – up to 40% of its own weight. Later, when it is heated up, the moisture evaporates and the silica gel (or another desiccant) can be used again. These moisture-absorbing properties not only make desiccant a valuable addition to the packaging of consumer goods but also an important component of so-called adsorption air dryers. Because all atmospheric air contains water vapor, compressed air contains a lot of moisture, which for most pneumatic applications first has to be dried. Traditionally, adsorption dryers accomplished this by forcing the compressed air through towers filled with thousands of these tiny desiccant beads.

A new drying technology, however, uses structured desiccant, also known as Cerades™. Instead of many small beads, Cerades consists of solid, ceramic blocks that dry the compressed air as it flows through straight, structured tubes. Because the air flow meets very little resistance, this process is much more energy efficient. Unlike the tiny beads that bounce around (and into each other) in a traditional adsorption dryer, structured, solid desiccant lasts a long time. This is particularly important because the decaying desiccant beads can negatively impact the dew point and the performance of the dryer. In addition, they produce a fine dust that not only has to be filtered out to maintain a high air quality but can also compromise the environment and the health of dryer operators. Structured desiccant does not have this problem and delivers its users ISO 8573-1:2010 Class 2 air purity for particles without any extra filtration. As a solid ceramic block, Cerades also offers greater installation and operational flexibility. For example, it can be mounted horizontally and is able to handle an inlet temperature of 70°C. This, combined with the fact that it is vibration-resistant and takes up less space, allows a structured desiccant dryer to be used in a wide range of applications, for example in the transportation industry.