ZEOZORB® Tank Vent Dryers

How Do Tank Vent Dryers Work?

Inhale Cycle

  1. During tank inhale (fluid exiting the tank), wet atmospheric air will enter through the base of the dryer and flow upwards through the absorbent.
  2. Dry air will then exit the top of the dryer entering the tank vent pipe and flowing into the tank.
  3. A series of internal flapper valves control the direction of air flow; directing the dry air during the inhale cycle into the tank.
  4. A glass sight window provides visual indication when the desiccant needs to be replaced. The adsorbent will change from blue to beige as it becomes saturated with water.

Exhale Cycle

  1. During tank exhale (fluid entering the tank), air leaking the tank will flow down the tanks vent pipe and into the Tank Vent Dryer
  2. A series of internal flapper valves control the direction of airflow; bypassing the absorbent and directing the exhaust air out of the vent cap on top of the dryer.



ZEOLITE adsorbent maximizes water adsorption capacity over a broad temperature range, providing less than 50ppm H2O

  • Quick and easy to install. Wall (715 & 720PE) or Floor Mounted (730)
  • 715 & 730 are constructed of 316 Stainless Steel with Viton seals
  • 720PE is constructed of Polyethylene (HDPE) with Viton seals
  • Low maintenance and easily refillable
    Easy, visible color indication of when adsorbent is due for replacement


QUICK FACT: 500 PPM (Parts Per Million) = 0.05% = 50cc of water in 1,000 liters of fluid.

Model Connection (Flange) Max fill or empty rate Amount of Desiccant Max fluid capacity related to desiccant content Applications
715 1.5 in 230 gallons/min 27.5 lbs 27,593 gallons Medium sized reservoirs, Containers, fuel tanks, gearboxes, medium storage tanks
730 3 in 916 gallons/min 110 lbs 109,972 gallons Large reservoirs, containers, large fuel tanks, gearboxes, large storage tanks


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