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Evaporation-based solar thermal distillation is a promising approach for purifying high-salinity water, but the liquid-vapor phase transition inherent to this process makes it intrinsically energy intensive. Here we show that the exchange of heat between the distilled and input water can fulfill a resonance condition, resulting in dramatic increases in fresh water production. Large gains (500%) in distilled water are accomplished by coupling nanophotonics-enabled solar membrane distillation with dynamic thermal recovery, achieved by controlling input flow rates as a function of incident light intensity. The resonance condition, achieved for the circulating heat flux between the distillate and feed, allows the system to behave in an entirely new way, as a desalination oscillator. The resonant oscillator concept introduced here is universal and can be applied to other systems such as thermal energy storage or solar-powered chemical reactors.
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This content will become publicly available on March 1, 2026
Brine management with zero and minimal liquid discharge
Zero liquid discharge (ZLD) and minimal liquid discharge (MLD) are brine management approaches that aim to reduce the environmental impacts of brine discharge and recover water for reuse. ZLD maximizes water recovery and avoids the needs for brine disposal, but is expensive and energy-intensive. MLD (which reduces the brine volume and recovers some water) has been proposed as a practical and cost-effective alternative to ZLD, but brine disposal is needed. In this Review, we examine the concepts, technologies and industrial applications of ZLD and MLD. These brine management strategies have current and potential applications in the desalination, energy, mining and semiconductor industries, all of which produce large volumes of brine. Brine concentration and crystallization in ZLD and MLD often rely on mechanical vapour compression and thermal crystallizers, which are effective but energy-intensive. Novel engineered systems for brine volume reduction and crystallization are under active development to achieve MLD and/or ZLD. These emerging systems, such as membrane distillation, electrodialytic crystallization and solvent extraction desalination, still face challenges to outcompete mechanical vapour compression and thermal crystallizers, underscoring the critical need to maximize the full potential of reverse osmosis to attain ultrahigh water recovery. Brine valorization has potential to partially offset the cost of ZLD and MLD, provided that resource recovery can be integrated into treatment trains economically and in accordance with regulations.
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- Award ID(s):
- 2452517
- PAR ID:
- 10614980
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature Reviews Clean Technology
- Volume:
- 1
- Issue:
- 3
- ISSN:
- 3005-0685
- Page Range / eLocation ID:
- 185 to 200
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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