Flex EDR Selective FGD Wastewater
Pilot Test Results
19 March 2019
Saltworks Technologies Inc. (Saltworks) completed an off-site Flex EDR Selective pilot test to treat flue gas desulfurization (FGD) wastewater from a coal fired power plant in China. The objective was to reduce chlorides such that the FGD wastewater could be internally recycled and final treatment costs reduced notably. FGD wastewater is generated and released primarily due to chloride content that inhibits sulfur absorption in the stack and can cause corrosion problems. If chlorides can be removed, the FGD wastewater can be recycled.
The results showed that Saltworks Flex EDR Selective achieved:
- Reliable treatment built from the second most common membrane desalination technology – electrodialysis reverse (EDR) – with modernized membranes and process controls.
- 90% recovery on a highly scaling calcium sulfate FGD wastewater without the need for expensive soda ash softening. The system produced a predominantly calcium chloride brine with 127,000 mg/L total dissolved solids (TDS) concentration. The brine could be directly solidified with fly ash and other solidification agents for zero liquid discharge, eliminating the need for a crystallizer.
- Removed 78% of the chlorides with ease: treated water from ~6,900 mg/L chlorides to less than 1,500 mg/L, such that it could be recycled back to the FGD system.
For the complete results of the pilot including detailed water chemistry and cost, sign-up below to download the free case study.