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Comment by viburnum | Hacker News Reader

Leftover brine is really a problem though

https://www.wired.com/story/desalination-is-booming-but-what...

I don't think it's just the brine that's concerning. Remember all of those toxic pesticides and heavy metals the author mentions? The ones causing health problems for residents of the Salton Sea area?

Those have to go someplace as well, and they would be mixed into that brine. Dumping a more concentrated version of that sludge into the gulf sounds like a bad time for people who live in the gulf region.

Don't get me wrong, I love this idea. I just know that there are hidden externalities here which need to be examined and dealt with properly.

It's not a huge problem: it's the same salt that was in the sea, just more concentrated. Dilute it well enough and it's a literal drop in the ocean.

The article also mentions that inefficient thermal desal produces much more brine, with modern RO desal being more efficient.

Yes just dilute it. In freshwater. Freshwater you got from ... where already ?

Why do you want to dilute it in freshwater?

Could we just... eat it? A by-product sounds a lot more efficient to access than mining. And people pay a premium for "sea salt."

Yeah I don't think you can just dump it in the top end of the gulf of california, especially if that's where you're sourcing feedwater.

Why not?

Existing ocean currents in the Gulf of California driven by wind, tides, and thermohaline circulation are on the order of 10cm/s, tens of kilometers wide, hundreds of meters deep. Very little of that is associated with local rivers, which are relatively tiny because the whole region is extremely arid. Are you going to be desalinating 0.1 km^2 of water per second?

The Sun pumps a thousand watts a square meter onto the surface of the Earth on a 24-hour cycle and this tends to shake things up.

The brine doesn’t spread out automatically, it sinks, and it’s deadly to aquatic life.

It does spread out automatically. We call it diffusion.

Diffusion can also be assisted with very modest power requirements.

Pump it into the Salton Sea.

It already has too much toxic salt dust blowing around.

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