Saltworks Launches Flex EDR
After Economic Zero Liquid Discharge Pilot

20 February, 2018

Saltworks Technologies achieved economic zero liquid discharge (ZLD) at a US chemical plant, treating challenging saline wastewater to 99.9% recovery.  The chemicals facility engaged Saltworks to rapidly deliver a pilot program that would remove salt from their effluent, helping to meet a discharge cap on total dissolved solids.

Upstream Pre-Treatment for Saltworks Flex EDR Electrodialysis Reversal Pilot Plant.
Saltworks Engineer working on Flex EDR Pilot Pre-Treatment Skid

The team targeted the highest salinity stream in the plant for salt removal. This concentrated stream, which also contained high organics and biological growth potential, was poorly suited for reverse osmosis (RO). Project leader Derek Mandel commented, “RO is the workhorse of desalination and we use it widely, however, the RO membrane fouling risk was too high with this wastewater. Extensive and uneconomic pre-treatment would have been required. This is why we worked with the client to test the second most popular membrane desalter – EDR.” EDR, or electrodialysis reversal, is an established water technology with more than half a century of industrial applications.

Saltworks’ Flex EDR introduces three essential innovations for EDR end users: (1) increased resilience via Saltworks’ IonFlux ion exchange membranes, which withstand turbid waters and frequent bleach cleans to prevent biological growth; (2) no need for chemical softening due to a patented hardness blocker protecting electrodes; and (3) process-control innovations to achieve higher recovery and optimize performance when facing variable inlet water conditions.

Flex EDR successfully extracted 89% of the salt load, surpassing the 75% goal. This de-risks the plant’s water balance and permit obligations. Downstream of Flex EDR, the concentrated brine was treated with the SaltMaker Evaporator Crystallizer to achieve 99.9% net water recovery in a modular package that produced solid byproduct. The solids were sent to non-hazardous landfills for safe, low-cost disposal.

Flex EDR Stack
Saltwork's Flex EDR - Next Generation Electrodialysis Reversal

This pilot demonstrated the economic and process advantages of targeting concentrated streams for salt removal. Today, Saltworks Technologies launches its Flex EDR product line – the next generation electrodialysis reversal technology for challenging waters:

  • Flex EDR Organix desalinates produced water and wastewater with high concentrations of organics, while removing the need for extensive pretreatment.
  • Flex EDR Selective pulls out monovalent ions with 98% selectivity, so you can tune water chemistries to suit your treatment needs and extract salts that deliver value.
  • Flex EDR Ammonia offers a membrane treatment system for reliable wastewater ammonia removal where biological systems struggle to meet requirements.

Sign Up for Updates

Get project & water treatment knowledge updates. 

Media Inquiries

Connect on Social Media