Saltworks Launches FlexEDR After Economic Zero Liquid Discharge Pilot
February 20th 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.
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’ FlexEDR 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.
FlexEDR successfully extracted 89% of the salt load, surpassing the 75% goal. This de-risks the plant’s water balance and permit obligations. Downstream of FlexEDR, 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.
This pilot demonstrated the economic and process advantages of targeting concentrated streams for salt removal. Today, Saltworks Technologies launches its FlexEDR product line – the next generation electrodialysis reversal technology for challenging waters:
- FlexEDR Organix desalinates produced water and wastewater with high concentrations of organics, while removing the need for extensive pretreatment.
- FlexEDR 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.
- FlexEDR Ammonia offers a membrane treatment system for reliable wastewater ammonia removal where biological systems struggle to meet requirements.