We use tandem water softeners. Due to unforeseen conditions, sodium hydroxide (caustic soda) water had transferred softener. During 5 hours the cationic resins are washed with sodium hydroxide mixture. Then resins block all the water flow in service operation. I am trying to find a method for cleaning and destroying stickiness situation. We have no time for resin discharge and load new cationic resins. How can we amend this terrible issue?
You didn't inform the NaOH concentration, my experiences for removing organic fouling in cationic resin Na-cycle. Every 3 month I was mixed NaOH with 1% only from NaCl weight per cycle regeneration.
For solving your you could neutralized your resin with HCl combine with oxalic Acid, 2:1, calculate with stoichiometric to the amount NaOH had used.
I produced solution. There is no any flow (flux) through the tank, completely blocked. I used hydroxide peroxide and citric acid to decrease pH from 9,2 to 3. I applied a technique for recirculating water. Before applying backwash+regeneration, We done a pipeline modification for giving compressed industrial air for open nozzle. Finally we applied 3 times heavy duty bachwash. The service flowrate reached the design value and completely unblocked situation is running.. This application took 7 hours . Thank you colleagues.
Oh wow, the caustic soda has chemically melted the resin into a single block of glued plastic. There is no getting around it, that’s a tank and resin replacement, sorry.