Technology

The Desiccant Material

In the ’50s, when the desiccant rotor dehumidifier was invented, lithium chloride salt (LiCl) was used as the main desiccant. LiCl absorbs moisture through a chemical reaction with the water molecules. Unfortunately, LiCl became volatile when exposed to humid air and this often caused the salt to deliquesce (dissolve). Salt dust was carried into the airflow that was deposited on system components as a very corrosive powder.

Today, most desiccant dehumidifiers use silica gel rotors. Silica gel adsorbs moisture from the air as water molecules effectively adhere to the molecules of silica gel. The main advantage of the D-Max silica gel rotor is that it is unaffected by humid or saturated air. Synthesized Silica Gel. If the silica gel is chemically bonded (synthesized) to the rotor material, the longevity is extended to (typically) in excess of 10 years. All our silica gel rotors are synthesized using metal silicates. No dust from the rotor 

Some rotors contain potential “loose” desiccant that can contaminate the air with dust particles. Apart from possible damage to products, the capacity of the rotor will soon deteriorate. Only rotors with synthesized silica gel will have no desiccant migration. Tests by the Fraunhofer Institute have shown there is no particle migration from our silica gel rotors. Washable – without capacity loss. If a rotor is exposed to contaminated air it is important that it can easily be washed on-site, without capacity loss. Returning a rotor to the manufacturer for cleaning is expensive and causes unnecessary equipment downtime.

Despite manufacturers’ claims, some silica gel rotors are not washable without significant capacity loss or material softening. The D-Max rotor is washable – without capacity loss or material softening. As a consequence of an electrical power failure, residual heat from reactivation heaters has resulted in some inferior silica gel rotors burning, causing irreparable damage to both the rotor and the dehumidifier. The D-Max silica gel rotor is non-flammable (Test Method – ASTM E84). No bacterial growth (bacteriostatic)Tests carried out by the Japan Food Research Laboratories on our standard silica gel rotors have shown them to be bacteriostatic. In addition, our SSCR-H rotor is both bacteriostatic and bacteriocidal.

The Consorb principle is normally used.

The new D-Max Rotor for Industrial Desiccant Dehumidifiers

Seibu Giken DST was the first company to develop a commercially available silica gel rotor. They remain the world leaders in desiccant rotor technology. All our industrial desiccant dehumidification systems now include the advanced D-Max silica gel rotor as standard. The D-Max manufacturing process includes the synthesizing (chemical bonding) of the silica gel to the rotor structure, resulting in a silica gel rotor of superior quality and exceptional longevity.
Following 10 years of continuous operation, our rotors retain more than 90% of the original capacity! The rotor is the single most important component in a desiccant dehumidifier. It is the rotor that determines the capacity, efficiency, and lifetime of the dehumidification equipment.

 

SG HQ