SSI Aeration has a wide range of membrane diffusers that are available in both EPDM and PTFE seats. Both types of valve seats have pros and cons, depending on the application.

EPDM (Ethylene Propylene Diene Monomer) membranes are more economical than PTFE, which makes them the ideal choice for plants operating on tighter budgets. They’re also more durable than PTFE, so they can be used for longer timespan before needing to be replaced or repaired.

As an industrial wastewater treatment system material, EPDM has a good resistance to heat, steam, and bright conditions that can degrade other materials over time. It’s also effective with a broad spectrum of chemicals that are common in industrial wastewater.

Over time, however, EPDM can begin to show signs of degradation as it ages and is exposed to harsh conditions. These issues include plasticizer leakage and creep, resulting in decreased oxygen transfer efficiency. This type of degradation can be addressed with protective coatings, extending the lifespan of the membranes.

PTFE is a thermoplastic polymer that’s famous for its nonstick properties. It’s also known for its toughness, elasticity, and self-lubricating characteristics.

PTFE is resistant to a large number of chemicals, including acids and caustics. It can be difficult to predict compatibility, so it’s important to consult a chemical compatibility chart. SSI Aeration’s PTFE/EPDM hybrid gasket has a self centering design that aids optimum sealing at lower bolt loads, reducing installation costs. This gasket features a bonded Teflon surface to ensure chemical and corrosion resistance with the EPDM elastomer for a complete solution.