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Saudi Thirst for Water Is Creating a Toxic Brine Problem

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Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#21

Post by Johnny555 »

hughdbrown wrote: post #14

> Saudi Arabia’s desalination plants produce about 31.5 million cubic meters of contaminated water each day. That volume of liquid, most of which is pumped back into the ocean, is equivalent to about 20 million barrels of oil a day, or, double the amount of crude it currently produces I don't understand the math. 31.5e6 cubic meters * 1e3 liters/cubic meter = 31.5e9 liters 31.5e9 liters / 3.78 liters/gallon = 8333333…

I don't understand the equivalence to oil at all -- are they saying that one barrel of this contaminated water has the same environmental impact of dumping a barrel of oil in the water?

I don't really understand the relevance of equating water waste to exports, if it were a nation known for pork exports, would they put the water volume in terms of hogs?

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#22

Post by TheBill »

systemfreund wrote: post #7
sp332 wrote: post #2

Why would they chlorinate the water before desalination? And where does the copper come from?

Apparently it's for prevention of fouling: > Combined low concentrations of copper (5 μg/l and chlorine (50,μg/l have been effective in preventing both micro and macro-fouling in over 120 seawater installations since 1987. https://www.researchgate.net/publication/242186534_FOULING_P...

It's also done in freshwater (great lakes) to prevent zebra mussels from clogging the intake pipes. Things like to grow where other things bring food by for free, and are sheltered from predators.

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#23

Post by sp332 »

Retric wrote: post #19
SolaceQuantum wrote: post #18

Earlier quoted context omitted.

The concern is not ocean-level damage through the salt directly but in localized ecological system destruction. The mangrove forest encompases a tiny portion of the ocean overall but removing this forest affects a large portion of sealife. The creation of 'deadzones' through salinity will have knockoff effects elsewhere that cannot necessarily be predicted.

At worst these dead zones would be tiny. They could dilute the waste stream by dumping it into the local sewage system, but I don’t think that’s going to change much. It’s on the order of building a mall parking lot. Sure bad for the local ecosystem, but we have vastly larger issues.

It's going to be dumped near the shoreline, where sea life is very different from what is supported in the open ocean. If the shoreline is made uninhabitable, the marine life there might not have anywhere else to go.

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#25

Post by refurb »

ricardobeat wrote: post #15
dsfyu404ed wrote: post #6

Earlier quoted context omitted.

Even if it's just extra salty it's still a local problem. You can't just dump it all in the ocean because it would still kill everything. You'd need to dump it out slowly or over a much wider area for the concentration not to be harmful. It's like a polluted river killing everything where it dumps out even if the amount of pollution is inconsequential overall.

Someone correct me if I'm wrong (not the best at math), but the ocean is massive . The entire amount of brine they mention (31.5 million cubic meters) fits in one 300m square cube. Even if you drop it in an enclosed 1km-wide area of seawater, it will barely increase concentration by 0.01%. It would take millenia for us to increase sea salinity by this method, and all that treated water is eventually coming back. Even…

Dissolution takes time. If we’re to dump the extra salty water off the coast, it would be hard to create an area of higher salinity.

Of course over time it would dissipate and barely change the salinity is the ocean.

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#27

Post by ryanmercer »

swebs wrote: post #17
dsfyu404ed wrote: post #6

Earlier quoted context omitted.

Even if it's just extra salty it's still a local problem. You can't just dump it all in the ocean because it would still kill everything. You'd need to dump it out slowly or over a much wider area for the concentration not to be harmful. It's like a polluted river killing everything where it dumps out even if the amount of pollution is inconsequential overall.

How about dumping it into a shallow pit and letting the water evaporate, creating new salt flats.

>Saudi Arabia emits 31.5 million cubic meters of liquid effluent a day

You'd need some massive pits and you'd have to displace way more than 31.5 million cubic meters of soil as it isn't all going to evaporate in a day. Ideally you'd want really shallow pools so you'd eat up an insane surface area.

For some reference an Olympic sized swimming pool is about 2,500 cubic meters so you'd need 12,600 (pools) just to hold one day worth of the contaminated water.

For a fun little compassion (that amuses me and might someone else) it is estimated that all of the silver ever mined adds up to about 166,375 cubic meters Source: https://www.usgs.gov/faqs/how-much-silver-has-been-found-wor...

And only about 8000 cubic meters of gold has been mined. Source: https://www.jmbullion.com/investing-guide/james/gold-supply/

Edit: derpity-derp-derp fix

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#28

Post by foobiekr »

swebs wrote: post #17
dsfyu404ed wrote: post #6

Earlier quoted context omitted.

Even if it's just extra salty it's still a local problem. You can't just dump it all in the ocean because it would still kill everything. You'd need to dump it out slowly or over a much wider area for the concentration not to be harmful. It's like a polluted river killing everything where it dumps out even if the amount of pollution is inconsequential overall.

How about dumping it into a shallow pit and letting the water evaporate, creating new salt flats.

the copper will be an issue.

Re: Saudi Thirst for Water Is Creating a Toxic Brine Problem

#30

Post by utexaspunk »

ryanmercer wrote: post #27
swebs wrote: post #17

Earlier quoted context omitted.

How about dumping it into a shallow pit and letting the water evaporate, creating new salt flats.

>Saudi Arabia emits 31.5 million cubic meters of liquid effluent a day You'd need some massive pits and you'd have to displace way more than 31.5 million cubic meters of soil as it isn't all going to evaporate in a day. Ideally you'd want really shallow pools so you'd eat up an insane surface area. For some reference an Olympic sized swimming pool is about 2,500 cubic meters so you'd need 12,600 (pools) just to hold…

Couldn't they just run a big pipe out into the middle of the desert and pump it there? Maybe they could create giant salt flats and extract rare earth elements from them, even...
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