Resin Cleaning

Prevention

100%

Efficiency

Unic Chem Ion Exchange Resin Cleaning

Maintaining the efficiency of ion exchange water softeners is essential for improving industrial water quality and preventing costly repairs. A reasonable interval between regenerations is typically three days, striking a balance between resin fouling and operational convenience.

Water softeners require low maintenance, with cation resin having a lifespan of four to five years before replacement is necessary. However, two primary issues can hinder their efficiency:

Fouling by Iron and Manganese
Fouling by Organics (e.g., tannins or humic acids)

Cation Resin Fouling

Iron and manganese, which are positively charged cations, can foul the cation resin similarly to calcium and magnesium. Unlike these minerals, however, iron and manganese are not effectively removed during brine regeneration, leading to accumulation with each cycle.

Iron Cleaning Products

Effective cleaning involves chemical methods that focus on lowering the pH of the resin column, enhancing iron solubility, and converting ferric iron to the more soluble ferrous form. Common practices include creating chelated compounds that do not adhere to the cation resin.

Typical Resin Cleaning Procedure Using INDO-6202

Most resin manufacturers recommend a sodium hydrosulfite dose rate of 1.25 pounds per cubic foot of resin. Here’s a step-by-step cleaning procedure:

Backwash the Resin: Start by backwashing the resin to remove any loose debris.
Regenerate the Resin with Brine: Conduct a standard brine regeneration.
Slow Rinse: Rinse the resin until a slight salty taste remains.
Isolate the Softener: Close the valves from the main outlet to isolate the system.
Depressurize: Remove the upper man-way cover or vessel head after depressurizing.
Adjust Water Level: Lower the water level above the resin bed to half its volume.
Prepare Sodium Hydrosulfite Solution: Create a concentrated solution to achieve a 4% concentration when mixed with the water above the resin.
Mix Solution: Thoroughly mix the sodium hydrosulfite solution with the water.
Drain Excess Solution: Drain the solution from the bottom of the softener until just above the resin bed.
Mix the Solution and Resin: Avoid using air sparging, as it can oxidize the sodium hydrosulfite, rendering it ineffective.
Soak the Resin: Allow the resin to soak for four to twelve hours.
Replace the Cover: Reattach the upper man-way cover or vessel head.
Drain and Rinse: Drain, downflow rinse, and backwash for 30 minutes.
Regenerate Again: Regenerate the resin with double the normal concentration of regenerant.
Return to Service: Ensure that the effluent pH level is normal before returning the system to service.

By following these procedures, you can effectively clean and maintain the efficiency of your ion exchange resin, ensuring optimal performance and longevity. For professional cleaning services and assistance, contact Unic Chem!