New method turns ocean water into drinking water, without waste
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Re: New method turns ocean water into drinking water, without waste
#2This appears to be the same New Rochester article as 4 days ago with 20 comments.
Re: New method turns ocean water into drinking water, without waste
#3This reads like hyperbole:
> The brine byproduct wreaks havoc on sea life when it’s deposited back into the ocean by raising the salt level and lowering oxygen in the water.
Managing return of concentrated brine should be entirely tractable in the literal ocean.
Re: New method turns ocean water into drinking water, without waste
#4There is a fundamental minimum amount of energy needed to desalinate: you can't take less energy to do it,than you could gain back (from osmotic pressure) if you allowed the desalinated water to expand a cylinder containing the residual brine. This is large. This paper is a thermal method, so it doesn't have an electricity input, but to justify their efficiency claim, they should really compare against what you could do by using the same surface area for solar panels, driving a conventional setup. My (limited) understanding is that conventional reverse osmosis is not far from the theoretical optimum, energy-wise, the main difficulties being operational (the membranes need declogging). And of course RO is more expensive than rain.
This paper is interesting, however, in directly producing crystalline salt, which is lower volume than brine and easier to dispose of, maybe even valuable.
Re: New method turns ocean water into drinking water, without waste
#5This reads like hyperbole: > The brine byproduct wreaks havoc on sea life when it’s deposited back into the ocean by raising the salt level and lowering oxygen in the water. Managing return of concentrated brine should be entirely tractable in the literal ocean.
Sure, but typically desalination plants are located in a single physical place, so a discharge pipe dumping brine 24x7 is bad for all of the things around it, as the local concentration is extremely high.
Re: New method turns ocean water into drinking water, without waste
#6This reads like hyperbole: > The brine byproduct wreaks havoc on sea life when it’s deposited back into the ocean by raising the salt level and lowering oxygen in the water. Managing return of concentrated brine should be entirely tractable in the literal ocean.
depends of course, how easy does the brine dissolve, how long does it take that it is so diluted that it can't do any harm, without that information it's not easy to tell
Re: New method turns ocean water into drinking water, without waste
#7This reads like hyperbole: > The brine byproduct wreaks havoc on sea life when it’s deposited back into the ocean by raising the salt level and lowering oxygen in the water. Managing return of concentrated brine should be entirely tractable in the literal ocean.
Sure, but typically desalination plants are located in a single physical place, so a discharge pipe dumping brine 24x7 is bad for all of the things around it, as the local concentration is extremely high.
Seems like you could run a long perforated tube to diminish that effect.
Re: New method turns ocean water into drinking water, without waste
#8Earlier quoted context omitted.
Sure, but typically desalination plants are located in a single physical place, so a discharge pipe dumping brine 24x7 is bad for all of the things around it, as the local concentration is extremely high.
Seems like you could run a long perforated tube to diminish that effect.
And it doesn't even need to be a rigid pipe. A flexible pipe made out of, say, waterproof fabric, could be cheaply made to extend miles while remaining open due to the pressure of the water pumped into it.
Re: New method turns ocean water into drinking water, without waste
#9This reads like hyperbole: > The brine byproduct wreaks havoc on sea life when it’s deposited back into the ocean by raising the salt level and lowering oxygen in the water. Managing return of concentrated brine should be entirely tractable in the literal ocean.
depends of course, how easy does the brine dissolve, how long does it take that it is so diluted that it can't do any harm, without that information it's not easy to tell
These are often built near shallower parts along the coast where changes are more pronounced.
Re: New method turns ocean water into drinking water, without waste
#10There is a fundamental minimum amount of energy needed to desalinate: you can't take less energy to do it,than you could gain back (from osmotic pressure) if you allowed the desalinated water to expand a cylinder containing the residual brine. This is large. This paper is a thermal method, so it doesn't have an electricity input, but to justify their efficiency claim, they should really compare against what you could…
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