There are several ways to desalinate seawater. The problem is to do so quickly and economically. Heating seawater then cooling and capturing the condensate takes too much energy to be really efficient. Perhaps these membranes, if they can be produced cheaply and will stand up to a large volume of water, are the answer. The problem still remains of disposing of the slurry of salt and other minerals. Currently most desalination plants return the sludgy, salty leftovers to the water supply, which is highly destructive of the environment.
Well, if we desalinize a lot of ocean water, that will take care of the rising ocean levels.
I understand that, but it is kind of interesting. The purified water recovered doesn't disappear from the water cycle, but is used and eventually reenters the cycle at some point, and that would include the oceans. In other words, the water your remove from the ocean eventually finds it's way back.
So, if you don't dispose of the salt and minerals recovered back into the ocean, won't that eventually throw off the salinity of the oceans by making them less salty than they should be?
Someone could invent a process that uses C02 and Skittles to produce limitless fresh water and the greenies would still ban it.
Returning sea salt to the sea shouldn’t be too destructive to the “environment.”
The Israelis are using it to build a rampart to slow the invaders who want to eventually overrun Israel.. Nice thread about it here a few weeks ago. Lots of pictures, too.
The Saudis and Israelis get a large chunk of their water from desalination. What do they do with the leftover brine?
Dump it back into the ocean. It’s not like they are making it saltier.
“The problem still remains of disposing of the slurry of salt and other minerals. Currently most desalination plants return the sludgy, salty leftovers to the water supply, which is highly destructive of the environment.”
That is an old environmentalist bromide used as an argument against desalination plants. The obvious solution is to dilute the filtered material before returning it to the ocean.
The following is from the Tampa Bay desalination plant website.
“At full capacity, the RO process leaves about 19 mgd of twice-as-salty seawater behind which is returned to Big Bend’s cooling water stream and blended with up to 1.4 billion gallons of cooling water, achieving a blending ratio of up to 70-to-1. At this point before entering and mixing with any bay water, the salinity is already only 1.0 to 1.5 percent higher, on average, than water from Tampa Bay. This slight increase falls within Tampa Bay’s normal, seasonal fluctuations in salinity.
The cooling water mixture moves through a discharge canal, blending with more seawater, diluting the discharge even further. By the time the discharged water reaches Tampa Bay, its salinity is nearly the same as the Bay’s. And, the large volume of water that naturally flows in and out of Tampa Bay near Big Bend provides more dilution, preventing any long-term build-up of salinity in the bay.
Tampa Bay Water’s comprehensive hydrobiological monitoring program collects thousands of samples including continuous salinity measurements every 15 minutes near the desalination facility. This and other water quality monitoring since 2003 shows no measurable salinity changes in Tampa Bay related to plant production.”
https://www.tampabaywater.org/tampa-bay-seawater-desalination