PTFE Membranes for Ozone

porous ptfe membranes for ozone check valve

PTFE Motionless™ Ozone Check Valve

Markel : Porous PTFE Membranes : Ozone Applications : Motionless Ozone Check Valve

Porous PTFE Motionless™ Ozone Check Valve:
A Breakthrough New Device for the Protection of Ozone Generators

Ozone is a powerful oxidizer that degrades over time the physical properties of many thermoplastics, thermosets, and rubber materials, and can also affect the physical properties of some metals. Mechanical devices such as check valves, which contain ozone sensitive plastics, rubber materials, and ozone sensitive metals, eventually fail or do not perform as designed in the prolonged presence of ozone.

 

To deal with the effect of ozone exposure to mechanical devices such as check valves, the decontamination market has undertaken aggressive maintenance programs such as the frequent replacement of these devices. However, replacing check valves every six months is no guarantee that they will not fail or operate as designed.

 

The Markel Motionless® Ozone Check Valve has no moving parts and is manufactured entirely of fluoropolymers. Fluoropolymers, as a family of plastics, are extremely resistant to ozone attack.

 

The Markel Motionless® Ozone Check Valve is designed to:

• Withstand water penetration over a range of time and pressures, protecting sensitive upstream ozone generation equipment

• Creates a manageable ozone gas pressure drop when compared to spring loaded mechanical check valves

 

The performance of this device allows for the elimination of process isolation mechanical check valves. An added benefit of the addition of the Motionless® Ozone Check Valve is that the costs associated with mechanical check valve change-out, plus ozone generator damage due to water intrusion, can be eliminated.

 

The most common means of generating ozone is corona discharge. Ozone is generated by supplying a dry process gas containing air, or oxygen across a dielectric in a high voltage electrode system. Because of the use of these high voltage fields, it is important to prevent water from entering the ozone generator. Much care and expense is taken to prevent water entry. Typical field installations can include liquid sensors, mechanical check valves, and drain traps.

 

The Motionless®Ozone Check Valve consists of a number of porous PTFE hollow fiber lengths, which are looped and inserted in a fluoropolymer tube. The open fiber ends are sealed in place with specialized fluoropolymer potting materials.

 

Ozone gas is fed into the fiber open ends and is allowed to pass freely through the porous wall of each fiber. If a process upset occurs, and water enters the ozone feed line and contacts the looped fiber end of the Motionless® Ozone Check Valve, the porous PTFE fiber will prevent  flow through the fiber wall because of the water rejecting properties (hydrophobic) of the porous PTFE.  

 

The Motionless® Ozone Check Valve can be easily inserted into ozone supply lines with the use of Stainless Steel or PVDF reduction compression fittings.  

 

The Markel Motionless® Ozone Check Valve can be designed for a variety of pressure drop – flow rate characteristics, suitable for small and moderately sized ozone generation systems. In each case, the end result is a design that will protect the valuable upstream generation equipment from water intrusion while minimizing the pressure drop of the ozone gas itself, and most importantly, eliminating the need for continual maintenance of mechanical check valves. The Motionless® Ozone Check Valve is a welcome addition to the list of equipment in the fight against eliminating water intrusion into ozone generators. 

Design and Product Options

Information to come.