EDR 101 Electrodialysis Reversal I

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Saltworks’ micro EDR stack (left) and full scale EDR stack (right)

• Transport salt ions from one solution to another solution through ion‐exchange membranes under the influence of an applied electric potential current

• SiSeparation is due to charge, not pressure or size differences.

Anion Exchange Membrane  Anions pass through Feed Feed Feed Feed  Cations blocked

Cation Exchange Membrane  Anions blocked  Cations pass through

Anode Cathode

Concentrate Product Concentrate Product

Copyright © 2015 Saltworks Technologies Inc. Operating Principle • Water flows paralle l to the membranes. • Positive ions flux through cation exchange membranes towards negative ly chhdarged catho de.

• Negative ions flux through anion exchange membranes towards positively charged anode.

• WtWater does not flux throug h the membranes. • Product stream becomes purer while concentrate stream becomes more concentttdrated with ions.

• Polarity reverses periodically to prevent fouling on the membranes • Product compartments and Concentrate compartments swap

Reversal

Organic and inorganic fouling removed from membranes by reversed movement of ions Reversal

Advantages Disadvantages •High recovery •Only removes ions; organics •Higher brine concentration and colloids not removed achievable as system is not • Selection of membranes and limited by osmotic pressure stacks highly dependent on • Little to no feed pre‐treatment feed water chemistry required • Built in chemical‐free scaling and fouling prevention due to periodic reversal feature

Ion exchange resin regeneration Inland brackish water Brine Aluminum anodizing AcidFood & Base & Brine BeverageRecovery ManagementManagement Concentrate brine Acid etching Electrodialysis Water softener Reversal Metal pickling

Wine tartaric Phosphogypsum Acid & stabili za tion wastewaters Food & AgricultureAgriculture Base RecoveryBeverage Water recovery, Agriculture recycling and reuse wastewaters

Saltworks offers five electrodialysis reversal products under the ElectroChem name:

Wastewater Desalination, wastewater treatment, Desalter water purifier/remediation/reclamation RO Brine Reverse osmosis brine concentrator Concentrator Salt Splitter Calcium sulphate, gypsum, water softener, tailings, acid rock drainage Produced Polymer, enhanced oil recovery Water Desalter produced water Acid Recycle Sulfuric/hydrochloric/hydrofluoric acids, Saltworks’ full scale skidded System battery acid, etching acid, aluminum anodizing acids ElectroChem system (5‐50 tonne/day)