Many fluids, semi-solids and powders are seriously effected by moisture and other contaminants. Most of the materials which are effected, are stored in tanks which are either located in the open and vented to atmosphere or are located in the process area and effected by other materials used in the same area.
The level of damage varies from rendering the materials useless to the lowering of efficiency and consequently the value.

The ingress of these contaminants occurs whenever material is drawn from the tank or by diurnal barometric pressure and thermal breathing caused by changes in ambient temperature. Moisture, in the form of water vapor, is the prime source of contamination and will cause simple dilution of acids, an increase in the corrosivity of oils and other fluids, fungal or biological activity in materials such as glycerol, or the lowering of electrical resistance of transformer oil sand similar materials.

In addition to water vapor, other contaminants which can be removed include: Acetone, Ammonia, Carbon Dioxide, Carbon Monoxide, Ethylene, Formaldehyde, Freon, Hydrogen Sulphide, Oxides of Nitrogen, Sulphur Dioxide, Toluene, Acid and Oil Vapors, etc.

Typical adsorbents used are: Molecular Sieves, Silica Gel, Activated Alumina, Activated Carbon, Soda Lime, Ethysorb, etc. The selective use of desiccants such as molecular sieves, silica gel and activated alumina, together with a wide range of other adsorbents in its tank vent dryers and adsorption units, enables Drytech to offer a high level of protection to a wide range of materials.

Typical materials which can be readily protected include: Acetic Acid, Brake Fluid, Ethanolamine, Genklene, Glycerol, Monomethylemethacrylate, Perklone® perchloroethylene (a trade mark of INEOS Chlor Limited), Polyalcohols, Polythers, Sulphuric Acid, Transformer Oils, Triklone® trichlorethylene (a trade mark of INEOS Chlor Limited), etc.
Unit of Measure

Connection (Flange)

N/A 1.5 in

Max fill or empty rate

N/A 230 gallons/min

Amount of desiccant

N/A 27.5 lbs

Max fluid capacity related to desiccant content

N/A 27,593 gallons


N/A Medium sized reservoirs,Containers, fuel tanks, gearboxes, medium storage tanks

Gross Weight

N/A 51 lb

Desiccant Volume

N/A 28 lb

Dimension "A"

N/A 1.5 in/NPT

Dimension "B"

N/A 10 in

Dimension "C"

N/A 12 in

Dimension "D"

N/A 7.5 in

Dimension "E"

N/A 1.9 in

Dimension "F"

N/A 2 in

Dimension "G"

N/A 10.25 in

Dimension "H"

N/A 15 in


Fluid contaminants will ingress into a tank or reservoir when material is drawn from the tank by operational demand (filling/cycling), thermal breathing, and barometric pressure changes. With a tank vent dryer in place, wet atmospheric air will enter the base of the vent dryer and flow upward through a bed of ZEOLITE desiccant removing water down to less than 100 PPM.

This VERY dry air will then flow into the storage tank or reservoir. By keeping the free air volume in the tank or reservoir constantly dry will actually liberate moisture from within the tank contents itself. This dynamic is vital for maximum performance and life of the materials being stored.

During exhale, or when the tank is being filled, it will push air from out of the storage tank and back into the vent dryer. The air will travel back through the tank vent dryer and hit a flapper valve, causing the air to vent to atmosphere, preventing any of the desiccant being contaminated from exhaled vapors. The valves work both ways essentially controlling the inflow and outflow of air to maximize performance.

N/A Drytech Tank Vent Dryers use a 1"-3" NPT connection into most tanks or reservoirs. If you have any questions on how to mount your tank vent dryer please contact our technical staff.

Installation Procedure:

  1. Remove dryer from plastic bag
  2. Remove safety cap from top of the dryer
  3. Fill dryer with desiccant if not filled
  4. Mount the dryer to the tank or reservoir using either floor or wall mounts

Disposal Procedure:

  1. Verify that the dryer is fully saturated - all blue beads will be beige in color
  2. Remove desiccant canister from vent dryer
  3. Dump desiccant contents into disposal bucket
  4. Verify and dispose of desiccant in accordance with your state and local environmental control regulations
  5. Review attached MSDS sheets



-Eliminate corrosion
-Eliminate fungal or biological activity
-Protect against high humidity and water condensation
-Protect against fluid contamination, dilution, and sedimentation - Maintain ISO cleanliness codes
-Extend life of hydraulic, lubrication, and process fluids -Extend MTBF and reduce O&M costs


1. ZEOLITE adsorbent

  • ZEOLITE adsorbent provides up to 28% by weight adsorption and provides clean dry air less than 100 PPM. ZEOLITE also maintains performance in high temperature environments, unlike Silica Gel.

2. Valved Controlled Airflow

  • All tank vent dryers use a series of flapper valves to control the inflow and outflow of air. This maximizes the desiccant performance and prevents desiccant contamination during exhale from tanks or reservoirs.

3. Robust Stainless Steel Construction

  • All Tank Vent Dryers are made of 316 stainless steel to withstand the elements and environment for decades. Viton O-Rings are also used for very harsh applications.

4. Color Indication

  • When maximum adsorption is reached, the blue indicating ZEOLITE beads will turn from blue to beige, to indicate that a replacement is required.

5. Easy to install & use

  • Tank vent dryers are easy to install and can either be wall or floor mounted. Floor mounted models feature a desiccant tray or lever which allows for easy desiccant replacements in the field.