EPRI Publishes Report: Successful FGD Industrial Water Reuse

"Chloride kidney" achieves 93% water recovery from flue gas desulfurization wastewater—without costly chemical pre-treatment

May 18th, 2022

Saltworks welcomes the publication of a new report by the Electric Power Research Institute (EPRI). The report summarizes results from a pilot project completed by Saltworks at one of the largest coal power plants in the US. The project employed Saltworks’ FlexEDR monovalent electrodialysis “chloride kidney” technology to treat flue gas desulfurization (FGD) wastewater at a coal-fired power plant. The project recovered 93% freshwater without the need for costly chemical softening.


The report, entitled “FGD Wastewater Treatment Testing Using a Saltworks FlexEDR Selective (Electrodialysis Reversal System) Technology”, gives an overview of treatment technologies, explains the need for selective chloride removal in FGD wastewater, and provides testing methodology and results that demonstrate FlexEDR’s performance. FlexEDR also previously won POWER Magazine’s 2020 Water Award following this same pilot project

A photo of a Saltworks FlexEDR pilot plant operating on-site at EPRI

The FlexEDR chloride kidney system builds on industrialized electrodialysis reversal by integrating Saltworks’ proprietary IonFlux selective monovalent anion exchange membranes (mAEM). These membranes selectively remove chloride ions while preventing sulfate from entering the brine. This prevents the formation of scale-causing calcium sulfate and avoids the need to remove calcium via expensive soda ash softening—a requirement of reverse osmosis systems aiming to achieve similar recoveries.


Saltworks’ FlexEDR systems are also engineered to operate reliably in the face of higher organic and particulate loads than those tolerated by reverse osmosis. This means FlexEDR offers vastly simplified pre-treatment and lowered capital and operating costs when treating FGD wastewater for chlorides, all while achieving a high water recycling rate.


Saltworks is proud to provide leading technologies that are backed by third-party data and analysis. The FlexEDR Selective system can remove monovalent ions from most industrial wastewaters. If you have wastewater that is blown down due to chloride concentration then reach out to Saltworks for a solution that selectively extracts chlorides and recycles wastewater in a singular, robust unit operation.

About Saltworks

Saltworks Technologies is a leader in the development and delivery of solutions for industrial wastewater treatment and lithium refining. By working with customers to understand their unique challenges and focusing on continuous innovation, Saltworks’ solutions provide best-in-class performance and reliability. From its headquarters in Richmond, BC, Canada, Saltworks’ team designs, builds, and operates full-scale plants, and offers comprehensive onsite and offsite testing services with its fleet of mobile pilots.

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