Reducing regenerant chemicals to meet regulatory compliance for industrial wastewater.
In 2009 the Iowa Department of Natural Resources (IDNR) instituted a chloride discharge reduction program to set target chloride levels at < 860 mg/L. Unfortunately, a major producer of frozen desserts in the state had chloride levels exceeding this parameter. To conform with the requirement, the production plant needed to reduce salt consumption to produce less chloride discharge in wastewater associated with boiler make-up water softeners.
Besides poor tasting water, chloride consumption generally does not pose a high risk for humans. However, excess levels can be a threat to the environment. If too much chloride run-off seeps into fresh water, it can create changes in the life cycles of animals and vegetation, altering the ecosystem.
Highly knowledgeable in water treatment and ion exchange products, an official Purolite distributor, WaterLink, recommended installing Purolite’s Shallow Shell™ SSTC60 resin—a high-performance sodium form resin used for industrial water softening. Shallow shell resin help optimize system performance and reduce operating costs by reducing leakage and conserving rinse water and regenerant chemicals. Of all the SST® products made developed by Purolite, Shallow Shell SSTC60 was selected because it has the highest regeneration efficiency and lowest salt consumption.
Shallow Shell SSTC60 was installed into three of seven wells at the plant location. Additionally, the Purolite Midwest Sales Manager issued a PuroPASS™ analysis of the plants softener regeneration process. PuroPASS is a comprehensive system audit and optimization service offered by Purolite to help customer’s gain important insight into treatment system. The analysis of the plant allowed Purolite technicians to determine how the company could get the most benefit from the resin by making some changes to the softener regeneration process.
The Shallow Shell resin, combined with regeneration step recommendations enabled the customer to achieve a 40% reduction in the chloride content of their wastewater—as well as a $100,000 savings in salt expenses annually. Additionally, the customer noted longer bed life time between softener regeneration. Due to the success of the trial, the plant installed Purolite’s Shallow Shell SSTC60 resin into all seven of their water softeners.
“We are very pleased with the results, notes Tony Bonacci of WaterLink.” He adds, “The efficiency of the Shallow Shell® resins enable more flexibility in the regeneration schedule for the softener vessels and save the operators and plant significant down time.” The softeners are monitored by WaterLink regularly to ensure that the system stays in compliance with chloride targets.
To learn more about how Purolite high-performance resins can optimize your softening system, contact your region technical sales office.