0000000000425942
AUTHOR
Marc Philibert
A new process for resourse recovery from surface water RO brine from permeate remineralization
Low-Pressure Reverse Osmosis (LPRO) membranes could be valuable alternatives to conventional surface water potabilization processes [1] thanks to a combined ability to: remove micropollutants, soften, disinfect and remove organic substances. However, these processes produce an aggressive permeate and a concentrated brine with discharge constraints [2]. Assisted Reverse Electrodialysis (A-RED, [3]) was tested for LPRO permeate remineralization by recovery of target minerals from the corresponding LPRO brine while maintaining the product water’s integrity with respect to the organic compounds present in the concentrate. Bench-scale experiments were carried out with SUEZ-WTS membranes (CR67T-A…
Surface water RO permeate remineralization through minerals recovery from brines
Assisted-Reverse Electrodialysis (A-RED) technology was applied following reverse osmosis (RO) of a surface water resource in order to recover minerals from its brine and directly remineralize the RO unit's permeate. Four different sets of cation/anion exchange membranes were benchmarked using single- and mixed-salts synthetic solutions as well as real brine and permeate streams produced from three-stage reverse osmosis applied to Seine River water. The process, operating under equal permeate and brine channel flows (2 cm/s velocities) and applied voltage varying from 0 to 10 V, showed viable remineralization results. Optimal recovery at 10 V applied allowed increasing permeate mineral cont…
Valorization of surface-water RO brines via Assisted-Reverse Electrodialysis for minerals recovery: performance analysis and scale-up perspectives
Reverse Osmosis (RO) plays a key role in seawater and brackish water desalination to fulfill the growing demand for fresh water. In recent years, RO has also been more and more adopted for the treatment and potabilization of surface waters, leading to two main problems: (i) the depletion in minerals of the product water, making it aggressive and unsuitable for drinking purposes and (ii) the production of a concentrated brine requiring proper disposal. Permeate remineralization post-treatments include pH adjustment and addition of minerals, such as bicarbonates, calcium and magnesium, which are essential for human health and required to meet drinking water guidelines. However, such solutions…