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The Dirty Truth About Turning Seawater into Drinking Water

earther.gizmodo.com

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Re: The Dirty Truth About Turning Seawater into Drinking Water

#3
> At the very least, we should be treating the brine so it’s safe to discharge into the ocean.

This amused me as I pictured people mixing newly produced fresh water with the brine and releasing this "new" seawater back.

Seriously though, I guess I assumed people were at least turning this stuff into salt. I watched a documentary on salt production (Italy I think) and they just got sea water and evaporated it in huge salt beds.

I kind of assumed the sea salt (Malden) I buy has been created using the same process.

Re: The Dirty Truth About Turning Seawater into Drinking Water

#4
> this salty-ass junk

Do you mean sea water? The amount of fresh water the human race will extract from the oceans will be what fraction of a percentage point of the total? Not accounting for, of course, the fact that most of it will make its way back to the oceans.

If pumping it back in has a local effect, then by all means try to mitigate that. But the idea that we're producing 'toxic waste' by creating saltier sea water is absurd.

What is with journalism today?

Re: The Dirty Truth About Turning Seawater into Drinking Water

#5

The desalinated water will end up back in the oceans eventually, so should the brine. Of course you can't just dump it back in directly, but if diluted and released responsibly, the ocean is the right place for the brine.

What do you dilute it with? You just spent a bunch of time and energy seperating water from it. I guess we should ship/pipe the brine to wastewater treatment facilities, and mix it with the treated waste before discharging it back into the ocean/river?

Re: The Dirty Truth About Turning Seawater into Drinking Water

#6
Just to be clear, "brine" isn't "salty water."

> This untreated salt water can’t just hang around in ponds—or, in worst-case scenarios, go into oceans or sewers. Disposal depends on geography, but typically the waste does go into oceans or sewers, if not injected into wells or kept in evaporation ponds. The high concentrations of salt, as well as chemicals like copper and chlorine, can make it toxic to marine life.

> “Brine underflows deplete dissolved oxygen in the receiving waters,” said lead author Edward Jones, who worked at the institute and is now at Wageningen University in the Netherlands, in a press release. “High salinity and reduced dissolved oxygen levels can have profound impacts on benthic organisms, which can translate into ecological effects observable throughout the food chain.”

It's an actual waste product that has to actually be responsibly handled. It's not "just the salty water from the ocean that we can dump back in however we want."

Re: The Dirty Truth About Turning Seawater into Drinking Water

#8
post #5

The desalinated water will end up back in the oceans eventually, so should the brine. Of course you can't just dump it back in directly, but if diluted and released responsibly, the ocean is the right place for the brine.

What do you dilute it with? You just spent a bunch of time and energy seperating water from it. I guess we should ship/pipe the brine to wastewater treatment facilities, and mix it with the treated waste before discharging it back into the ocean/river?

Seawater (edit: and air, too. one of the problems is the brine has little dissolved oxygen).

Re: The Dirty Truth About Turning Seawater into Drinking Water

#10
post #7

> In fact, the study concluded that for every liter of freshwater a plant produces, 0.4 gallons (1.5 liters) of brine are produced on average. How does removing water from solution makes more of that solution?

2.5 L of water go in.

1 L freshwater comes out of pipe A.

1.5 L wastewater comes out of pipe B.

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