Vents and Scrubbers

Venting Requirements for Poly Tanks

Mechanical Pump Fill Pneumatic Fill
IF ≤ 1,000 gallons IF - Vent length ≤ 3' IF - Vent length > 3' and ≤ 30' IF - Scrubber application
✔ Vent size should equal size of largest fill or discharge fitting ✔ Maintain vent screen mesh size ≥ 1/4" or no screen used ✔ 3 or less 90º elbows with no other restrictions or reduction in pipe size ✔ Vent pipe size throughout scrubber system CANNOT be reduced!
✔ Centerline of dispersion pipe not to be submersed > 6"
IF > 1,000 gallons ✔ Emergency Pressure Relief Cover Required IF > 1,000 gallons ✔ Emergency Pressure Relief Cover Required IF > 1,000 gallons ✔ Perforated dispersion pipe must be same diameter as vent or larger. Sum of perforations ≥ cross-sectional area of pipe
✔ Vent size should exceed the largest fill or discharge fitting by 1"
Tanker Discharge Inlet/ Fitting Size Min Vent Size Tanker Discharge Inlet/ Fitting Size Min Vent Size Tanker Discharge Inlet/ Fitting Size Min Vent Size
2" 2" 4" 2" 2" 6" 2" 2" 6"
3" 2" 6" 3" 2" 6" 3" 2" 8"
3" 3" 6" 3" 3" 8" 3" 3" 10"

Click to see guidelines for vent placement.

Venting charts based on recommendation and criteria from Venting Design for ACFM Technical Paper.

U-Vent

U-Vent

Standard venting for outdoor tanks or for storing chemicals that create fumes. In PVC, in sizes 2 to 6 inches.

Drawings

Mushroom Vent

Mushroom Vent

For day tanks, an economical alternative to traditional U-vents or fittings. Made of polypropylene, in sizes 1 to 3 inches.

Drawing

8” Mushroom Vent Assembly

8” Mushroom Vent Assembly

Until now, space-consuming (and expensive) large vents or multiple vents were necessary to meet venting requirements in order to maintain the warranty. Our solution is an 8” mushroom vent, which is available as a complete assembly in a standalone version. This mushroom vent has been used by Poly Processing Company for several years as part of the F.S. 2650 manway cover. The vent now comes with a flange molded into it so that it can be installed on the dome of the tank to give you greater venting capacity. This is a more cost-effective alternative to many other venting systems.

Like the F.S. 2650, the mushroom vent comes with an HDPE screen to prevent birds from nesting and debris from plugging the vent.

Download a drawing

PolyScrub™ and PolyScrub Plus™

PolyScrub™ and PolyScrub Plus™

We have the ability to produce simple to more complex scrubbers based on our client’s need. Our standard scrubber PolyScrub is comprised of a submerged plenum, which allows fumes to bubble through a water bath. We also have the ability to supply automated PolyScrub Plus systems which will monitor scrubbed air and give you the automation you need for maintaining a neutral PH system. 

Literature