Technology: D-Max Silica Gel Rotor

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 most important single component in a desiccant dehumidifier. It is the rotor that determines the capacity, efficiency and lifetime of the dehumidification equipment. The following factors should be considered:-

The Desiccant Material

Back in the fifties 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.

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

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.

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 Frauenhofer Institute have shown there is no particle mitigation from our silica gel rotors


As a consequence of an electrical power failure, residual heat from reactivation heaters have resulted in some inferior silica gel rotors to burn, causing irreparable damage to both the rotor and the dehumidifier.

The D-Max silica gel rotor is non-flammable (Test Method – ASTM E84).

D-MAX - Silica Gel Rotor

D-Max is the next generation of silica gel rotors from Seibu Giken and offers an increase of up to 15% in drying capacity when compared to our original SSCR-U rotor.

The silica gel is chemically bonded to the structure, meaning that there is no desiccant carry-over to the air while also ensuring an excellent lifetime, often in excess of 10 years.

The D-Max rotor can be washed if it becomes contaminated.A new feature with the D-Max rotor is that it is bacteriostatic and fungi-static, meaning there will be no growth of bacteria or fungus on a the rotor material.

SSCR-CI - Silicon Free

The unique SSCR-CI rotor is a 100% silicon-free sorption rotor without loss of dehumidification capacity.

Used in the automotive & pharmaceutical industry or in environments that require silicon-free air.

Thanks to thorough research, Seibu Giken have managed to produce the only 100% silicon free rotor on the market.

SSCR-CI can be used to replace existing dehumidification rotors.

SZCR - Zeolite

This Zeolite rotor from Seibu Giken is developed for dehumidification to very low dew points.

Reactivation temperatures are much higher than used on standard silica gel rotors.

SCCR-H - Bactericidal & Hygienic

A desiccant rotor specifically developed for the food and pharmaceutical industry.

The SSCR-H is bacteriostatic and bactericidal – the rotor surface effectively eliminates airborne bacteria. It was successfully tested in the Japan Food Research Laboratories in 2001.SSCR-H rotors are not washable.