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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
- Void
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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.
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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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