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#1 2024-08-27 09:01:25
- tahanson43206
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Desalination Technology
SpaceNut, the forum had three topics with the word "desalination" in the title, but nothing for a collection about the technology itself.
The YouTube video at this link: https://www.youtube.com/watch?v=wVW2-UA0SB4
has a number of comments inspired by the video.
Many of the comments are critical of the ideas given in the video.
What came across to me is the great variety of solutions/recommendations contributors seem to think might work.
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#2 2024-08-27 09:01:52
- tahanson43206
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Re: Desalination Technology
This post is reserved for an index to posts NewMars members may contribute over time.
#3:Terraformer: http://newmars.com/forums/viewtopic.php … 18#p230018
Vacuum distillation for ships
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#3 2025-02-25 11:50:33
- Terraformer
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Re: Desalination Technology
Single stage desalination system for ships.
Uses vacuum distillation. Energy intensive, at 748.5 kWh per tonne; however, 740 kWh of that is low grade heat to evaporate the water. Very simple design, no complex and expensive membranes needed. Something Martians could build and maintain and I expect a lot more tolerant of brine content than reverse osmosis is.
If the vapour was condensed using compression, could we recover some of the heat to use for further desalination? If using warm seawater, could we limit the extraction to what is achievable with the energy content of the seawater itself, so only removing say 4% of the water and discharging a cold slightly saltier brine that would have quite a low environmental impact? That would let us use the entire sea surface to collect the required thermal energy.
Use what is abundant and build to last
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#4 2025-02-25 12:35:36
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Re: Desalination Technology
Forced distillation does reuse the heat from the compression of steam to distilled water. The heat is shunted back to the boiler/evaporator/vacuum chamber.
Ending Pending 
Is it possible that the root of political science claims is to produce white collar jobs for people who paid for an education and do not want a real job?
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#5 2025-07-11 20:56:11
- tahanson43206
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Re: Desalination Technology
Here is a report on doing desalination under sea water ...
https://www.msn.com/en-us/weather/topst … c476e&ei=9
The "secret" is to pull water rather than push it. The result is a significant savings in energy required per liter of fresh water. The method also is less disruptive to the ocean because the brine that is released is less concentrated.
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#6 2025-08-10 06:48:56
- tahanson43206
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Re: Desalination Technology
This is a follow up report on companies doing undersea desalination....
https://www.yahoo.com/news/articles/com … 00322.html
This is the same technology as reported in Post #5, with details of companies and locations where the system is already in place or under construction.
Companies announce game-changing plan to harvest drinking water from the ocean floor — here's how it works
Yei Ling Ma
Sun, August 10, 2025 at 6:30 AM EDTCompanies announce game-changing plan to harvest drinking water from the ocean floor — here's how it works
Three companies are leveraging modern technology to reshape the future of commercial desalination, making the process cleaner, smarter, and more cost-effective, the Wall Street Journal reported.
Safe drinking water helps prevent the transmission of preventable diseases like "cholera, diarrhoea, dysentery, hepatitis A, typhoid, and polio," per the World Health Organization. Yet, more than four billion people in 135 low- and middle-income countries across the world lack that, according to a 2024 study published in the journal Science.
Access to fresh drinking water is shrinking as global water usage increases, driven by industries like agriculture and new technology like artificial intelligence.
Desalination appears to be the most logical solution since 97% of the Earth's water is found in the ocean.
However, traditional commercial desalination methods like thermal desalination and reverse osmosis are highly energy-intensive and expensive.
Seawater reverse osmosis requires significant energy to pressurize water that passes through a semi-permeable membrane. This membrane filters out salt and impurities, allowing only water molecules to pass through. This process creates a concentrated brine byproduct that can harm aquatic life when deposited back into the ocean.
Thermal desalination leverages heat energy to remove salt from the water. The process involves heating the water to produce steam, which naturally separates from the salt and minerals, and turns back into fresh water when the steam has cooled. Thermal desalination also requires a lot of energy to heat water at scale.
Dirty fossil fuels power these methods, and they remain expensive compared to alternative methods of harvesting freshwater.
Flocean, Waterise, and OceanWell are three water desalination companies that are thinking outside the box.
Instead of wasting energy to pressurize the water to pass through filter membranes, could the desalination process harness the ocean's natural water pressure to do the same thing?
By using deep-sea technology, including deep-sea robots and undersea power cables, and submerging the filter membrane to a depth of at least 400 meters, or 1312 feet, the water pressure at that depth will naturally flow through the desalination membrane. According to the Wall Street Journal, this deep water desalination process can save up to 40% on energy usage.
In addition to the benefits of working at that depth, the harmful brine byproduct the process creates can be dispersed quickly back into the ocean, minimizing harm to aquatic life.
Flocean and Waterise have established their pilot desalination plants off the coast of Norway, and OceanWell has built its plant at a reservoir in California's Las Virgenes Municipal Water District, per the Wall Street Journal.
These companies are seeking government contracts that will help further develop and make more accessible this cleaner, desalination process.
Currently, Flocean is supplying ultra-pure water to a local Norwegian company to make premium-craft cocktail ice. The company also has a contract with Mongstad, an oil refinery facility, to produce about 264,000 gallons of desalinated water per day, expected to launch by the second half of 2026.
Waterise has entered a contract with Jordan Phosphates Mines, a mining company based in Jordan, agreeing to supply 6.6 million gallons of desalinated water per day from the Gulf of Aqaba, south of Jordan.
Most commenters seemed intrigued and hopeful about this new desalination process. However, others questioned the logistics behind the process.
"But they still need to pump that fresh water from the depths to wherever it's going on land so it's hard to see where significant energy savings comes from," one commenter pointed out.
Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
A savings would come from not having to set up processing facilities on land. The "land" is free, at the bottom of the ocean, until some government decides to tax it.
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#7 2025-10-20 21:06:24
- tahanson43206
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Re: Desalination Technology
This post is about desalination of salty water using solar energy. Ma Nature uses solar energy to desalinate sea water.
The system described in the article at the link below apparently combiners solar panel technology with desalination.
https://www.yahoo.com/news/articles/sci … 00725.html
Ulsan is a university in South Korea
Scientists make incredible breakthrough to pull clean drinking water from the sea: 'An amazing leap forward'
Audrey Brewer
Sun, October 19, 2025 at 6:30 AM EDT
2 min readScientists make incredible breakthrough to pull clean drinking water from the sea: 'An amazing leap forward'
Scientists have developed a novel technology to further advance water desalination — the process of removing salt from seawater — potentially offering a large-scale solution for an imperiled freshwater supply.
A team from Ulsan National Institute of Science & Technology has developed new desalination technology that utilizes solar power for energy, according to a report from Interesting Engineering.
The method uses an oxide perovskite — which traps heat and converts it into energy without any carbon emissions, making it an overall cleaner process — in the solar panels.
Researchers also developed a device to overcome salt accumulation, a common problem in desalination. Their design uses a one-directional fluid flow, creating a salt gradient that pushes salt to the edge of the solar panels, improving light penetration by clearing away salt crystals after they're removed from the water.
"This work demonstrates a breakthrough approach to enhancing the efficiency and durability of solar desalination through advanced material engineering and smart design," the team told Interesting Engineering.
According to the researchers, who published their work in the journal Advanced Energy Materials, they've already seen an impressive evaporation rate of 3.4 kilograms of freshwater (about 7.5 pounds) per hour, and sturdy operation with solutions containing 20% salt, which is far saltier than regular seawater.
"This breakthrough provides a practical and scalable solution to the global water scarcity crisis," Professor Ji-Hyun Jang explained. This technology represents an amazing leap forward in desalination, creating more freshwater for those in need.
Lack of access to potable water impacts over four billion people globally, and the situation is likely to worsen with the increased prevalence of droughts, extreme weather events, and changes to the water cycle.
A traditional downside to the desalination process is that it typically requires significant energy derived from dirty sources, making it a more expensive and environmentally detrimental process. The fact that the system uses solar power makes it a much cleaner option and an even more cost-effective approach over time.
Desalination isn't a perfect process, but the National Institute of Health indicated that there are ways to mitigate its impacts and utilize it to support the water cycle at scale.
Harnessing the power of the sun to ensure better access to safe water ultimately benefits everyone.
It is encouraging to see that the researchers tested with brine concentrated greater than sea water on Earth. Much water on Mars is going to be loaded with salt.
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#8 2025-10-21 14:55:03
- SpaceNut
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Re: Desalination Technology
Opening was about "Unlimited Fresh Water: Can Glass Domes Save Us?" where the water evaporates within a small space and is cooled once it reaches the top sort of like a still.
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#9 2026-05-12 21:05:33
- tahanson43206
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Re: Desalination Technology
This post is about research to try to replace Titanium in metal parts in desalination plants.
a-new-super-steel-survives-the-extreme-conditions-needed-to-split-seawater-into-green-hydrogen-solving-a-corrosion-problem-that-stumped-engineers-for-years/
The research is encouraging but it is laboratory level.
AI Overview
A University of Hong Kong team led by Professor Mingxin Huang developed an "ultra stainless steel" (SS-H2) that resists extreme corrosion during seawater electrolysis for green hydrogen production. By forming a unique double-layer passive film (chromium and manganese-based), it survives high anodic voltages (up to 1700 mV) that destroy conventional steel, offering a low-cost alternative to titanium, potentially cutting structural material costs by up to 40-fold.
Key Breakthroughs and Technical Details:The Corrosion Solution: Conventional stainless steel fails in seawater because chloride ions destroy its chromium oxide layer. The new SS-H2 adds a secondary manganese-based passive layer that activates at
, providing a "dual-barrier" that defies traditional corrosion science.
Performance: The alloy resists pitting corrosion under intense, long-term exposure to seawater, maintaining stability at voltages up to 1700 mV.
Cost Efficiency: Replacing titanium (a standard, expensive material in current electrolyzers) with this new steel could make seawater-to-hydrogen production commercially viable.
Status: While laboratory results are promising, the team is working on converting the material into practical, industrial-scale products like meshes and foams.This innovation addresses the long-standing challenge of creating affordable, durable electrolyzers that can operate directly in seawater without needing expensive, purified water or rare metals.
ScienceDailyhttps://www.sciencedaily.com
“Cannot be explained” – New ultra stainless steel stuns researchers
May 10, 2026 — A team at the University of Hong Kong has developed a new “super steel” that can survive the harsh conditions needed to make green...
Fuel Cells Workshttps://fuelcellsworks.com
Ultra Stainless Steel SS-H2 Revolutionizes Green Hydrogen
May 11, 2026 — A Steel Breakthrough With Clean Energy Potential SS-H2 is not yet a plug and play solution for the hydrogen economy. The team has ...
The Brighter Side of Newshttps://www.thebrighterside.news
New type of stainless steel pulls hydrogen directly out of ...
May 11, 2026 — That quote gets at what makes the work stand out. The researchers are not just reporting a better-performing alloy. They are descr...Show all
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#10 2026-05-27 21:11:04
- tahanson43206
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Re: Desalination Technology
The story at the link below is about desalination technology
solar-powered-desalination-system-turns-ocean-water-into-drinking-water-without-waste
Here is a link to the original story:
https://www.rochester.edu/newscenter/wh … er-704732/
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#11 2026-05-30 13:02:32
- tahanson43206
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Re: Desalination Technology
The story at the link below is about desalination technology using laser cut ridges in aluminum:
https://www.msn.com/en-us/weather/topst … -out-salt/
This may be the same story as reported in Post #10
Engineers just built a solar still that pulls fresh water straight from the ocean — a laser-etched black metal that drinks brine and spits out salt
Story by Everett Sloane • 5h •
5 min readEngineers just built a solar still that pulls fresh water straight from the ocean — a laser-etched black metal that drinks brine and spits out salt
© adhitya_2505/UnsplashA sheet of aluminum, etched with billions of microscopic grooves by a femtosecond laser, sat angled toward the sun in a University of Rochester lab for seven straight days. Saltwater crept up its surface against gravity, evaporated without any pump or chemical input, and left behind neat ridges of crystallized salt along the panel’s edges. No concentrated brine dripped back into the water supply. No membrane needed replacing. The device just kept running.
The results, published in spring 2026 in Light: Science & Applications, a Nature Portfolio journal, describe what the Rochester team calls a “superwicking black metal” solar still. If the approach survives the jump from benchtop to coastline, it could give communities a way to desalinate seawater without producing the toxic brine that conventional reverse-osmosis plants dump back into the ocean.
How the panel actually works
The secret is in the surface. Femtosecond laser pulses, each lasting a quadrillionth of a second, carve micro- and nanostructures into ordinary aluminum. The resulting texture does two jobs simultaneously: it turns the metal nearly black, absorbing over 99 percent of incoming sunlight and converting it to heat, and it creates a network of tiny channels that pull a thin film of saltwater upward through capillary action alone.
As sunlight heats the film, water molecules evaporate off the surface. Dissolved salts, left behind, migrate along the wicking channels toward the panel’s edges, where they crystallize into solid deposits. Those deposits can be brushed or shaken off without shutting the system down.
That geometry solves the problem that has plagued solar evaporators for years: fouling. Most designs that absorb sunlight efficiently also clog with salt within hours or days, choking off evaporation. By routing crystallization away from the active evaporation zone, the Rochester panel kept its central surface clear for the full seven-day test without visible performance loss.
The technical lineage
The panel did not appear out of nowhere. The same Rochester research group, led by optics professor Chunlei Guo, laid the groundwork in a 2020 study published in Nature Sustainability.
That earlier paper demonstrated that femtosecond laser processing could create aluminum surfaces capable of rapid uphill water transport and showed that angled panels could maintain a thin evaporating film across a range of sun positions. The 2026 crystallizer builds directly on that foundation, adding the controlled salt-deposition step and proving the system can run continuously for a week under laboratory conditions.
Separately, a different research team tested a passive floating solar still in Atlantic waters near Halifax, Nova Scotia, and reported reductions of dissolved salts and heavy metals by orders of magnitude. That device used different materials and a different architecture, so its durability numbers do not transfer directly to the Rochester design. But the Halifax deployment does confirm a broader point: passive solar stills can function in real ocean conditions, not just under lab lighting.
Why zero liquid discharge matters
Conventional reverse-osmosis desalination plants push seawater through semi-permeable membranes at high pressure, separating fresh water from a concentrated brine stream. That brine, often laced with antiscalants and cleaning chemicals, gets pumped back into the sea. A 2019 study in the journal Science of the Total Environment estimated that global desalination plants produce roughly 142 million cubic meters of brine daily, raising salinity and chemical concentrations in discharge zones and stressing marine organisms from plankton to fish.
The Rochester panel sidesteps that problem entirely. Salt leaves the system as a solid, not a liquid. The researchers describe the process as “zero liquid discharge,” meaning no concentrated wastewater stream is generated at any point. At bench scale, the claim is supported by the published data. Whether it holds at larger scales and over longer periods is a different question.
What the research has not yet shown
Seven days is a proof of concept, not a track record. A practical desalination system would need to run for months or years, enduring fluctuating salinity, biofouling, storm waves, and seasonal temperature swings. No multi-month deployment data for the superwicking panel has been published.
Scale is an open challenge. The experiments used relatively small panels under controlled illumination. A community-scale installation would require many square meters of laser-textured metal, structural supports to keep panels oriented toward the sun, and protection against wind, salt spray, and corrosion. Whether edge crystallization still works cleanly when panels are joined into large arrays has not been tested in the peer-reviewed record.
Cost is perhaps the most pressing unknown. Femtosecond lasers are precision instruments typically found in research labs, and the energy and processing time required to texture aluminum at commercial scale have not been broken down in the published methods. The University of Rochester’s press materials describe the process in general terms but provide no per-panel cost estimates or energy budgets. Without those numbers, comparing the cost of water from these panels to that of existing RO infrastructure is not possible.
The researchers also describe “simultaneous complete mineral mining from ocean water,” but no published data breaks down the purity or commercial value of the recovered salt crystals. Whether those deposits are clean enough for industrial use or require further refining remains unaddressed. Claims about offsetting desalination costs through mineral sales are, for now, speculative.
And zero liquid discharge, while a genuine advance at bench scale, does not automatically mean zero environmental impact. Large fields of dark, heat-absorbing panels could alter local microclimates. Aluminum surfaces exposed to seawater will face corrosion and biological growth over time. Independent environmental assessments have not yet been conducted.
Where the technology stands in mid-2026
The physics are sound. Superwicking, high solar absorption, and edge-directed crystallization each have independent experimental support, and the Rochester team’s contribution is integrating all three into a single device that ran for a sustained period without fouling. That integration is genuinely new and addresses the specific failure mode that has stalled earlier solar evaporators.
But a seven-day lab demonstration and a deployable water system are separated by years of engineering, field testing, and cost reduction. The next milestones to watch for are multi-month ocean trials with continuous monitoring of water output rates, salt balance, and panel degradation, followed by independent third-party verification of the zero-liquid-discharge claim under variable real-world conditions. Until those results appear, the superwicking black metal panel is best understood as a compelling proof of principle: a device that shows laser-etched aluminum can turn sunlight and seawater into fresh water and solid salt, with no brine left over, and that keeps working long enough to suggest the approach deserves serious investment in scaling up.
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