Permutit® Double Dish Underdrain System

The Permutit® double dish underdrain system answers the need for a highly efficient, yet, simple, underdrain system. It can be used in softeners and demineralizers and is practical for lined or unlined vessels of any diameter. We can provide vessels with an installed double dish underdrain or we can just provide a double dish underdrain for your existing system.

The Permutit brand of products, such as the double dish underdrain, became a part of Siemens in 1993.

Permutit double dish underdrains have been installed in many applications worldwide and its design is based on the use of a false bottom or second tank head (the double dish) that contains a series of strainers in a calculated and predetermined pattern. The double dish is of slightly greater radius than the actual tank bottom and minimizes the inactive areas at the bottom of the ion exchange bed. The strainers retain the ion exchange media and eliminate any requirements for conventional sub-fill, such as gravel, quartz, anthracite, etc.

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Features and Benefits

Permutit double dish underdrain benefits include:

No subfill needed to retain ion exchange media
Corrosion resistant, durable construction
Reduced rinse water requirements
Uniform collection and distribution of water during service, backwash, regeneration and rinse cycles