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Funding Information: The authors are grateful with Arauco Bioforest S.A. for giving the right to use the presented results. Publisher Copyright: © 2021 The Authors A pulsed electrodialysis reversal (pEDR) process is proposed to desalinate spent water after particle removal, biological and chemical coagulation, which are commonly used as a sequence in Kraft pulp mills. pEDR affords closed-loop processing, reducing the need for freshwater intake while maintaining the quality of recirculating process streams. Compared with conventional electrodialysis, pEDR minimizes production losses (from 5 % to 0.6 %), extending the time for hydraulic reversal (from 15 min to at least 2 h). Simultaneously, the conductivity of the effluent is significantly reduced, from 2100 to 200 μS/cm, reaching a quality similar to the feed water. The operation cost (0.38 US$/m3) is factored in the techno-economic viability of the process water recirculation, which is also demonstrated for its scalability. Additionally, WinGEMS simulation highlights the benefits of installing a pEDR unit, positively impacting mill water under different recirculation rates. Overall, we show remarkable gains in water economy, operation (maintenance and fouling), and quality, which are critical factors in achieving resource sufficiency.

In order to simply and safely treat radioactive iodine waste, a study of the removal of iodide ion from radioactive waste using electrodialysis with an anion exchange paper membrane, in which trimethylhydroxylpropylammonium groups were homogeneously dispersed with high density. In Na125I and Na36Cl concentration-cell system, electric ion and water conductances, phenomenological coefficients, have been experimentally determined on basis of nonequilibrium thermodynamics. Prepared paper membrane had higher permselectivity of 125I ion than 36Cl ions by approximately 21%. On the other hand, water flux that was accompanied by an ionic transference in prepared paper membrane was greatly larger than that in typical synthesized membrane. It is suggested that a depression of water mobility is important to practice an ideal radioactive iodide waste electrodialysis system with a novel anion exchange paper membrane.