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Regeneration of ion exchange units

I am actually thinking about rinsing my ion-exchange units, after HCl/NaOH injection in a counter current direction. Will this help in improving the efficiency of my units, if yes how?

Ravikumar Abbigeri
Engineer - India
2005

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Unless I am misunderstanding, this is called "backwashing". I think if you google with that term it will be explained.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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Ted is correct. Backwashing (which some people confuse with regeneration) is always done in the reverse direction from the service flow. It serves to mix up the resin, which tends to start sorting itself by particle size during service, and to remove trash, dirt, etc. that tends to deposit on top of the resin bed.

A backwash step should be part of the regeneration cycle - that's standard practice, as far as I know.

Dave Wichern
Consultant - The Bronx, New York
2005

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Not if your doing a counterflow regeneration, its not, or if you have adequate pre-filtration - down to 0.5 to 1 micron before the IX system. That can eliminate a significant amount of water created in the regeneration cycle. He might be discussing using incorrect terminology a counterflow regeneration process, which would improve the efficiency of the regeneration process and the quality of the effluent produced. Too many variables to consider here, with not enough information!

Tom Baker
wastewater treatment specialist - Warminster, Pennsylvania
2005

 

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Thanks, I stand corrected. My knowledge of ion exchange processes is a little dated. But, backwashing used to be standard practice, in so far as I understand, because the regenerant flow rate was insufficient to "fluff" the resin. If I may ask, what changed?

Dave Wichern
Consultant - The Bronx, New York
2005