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xilman 2016-07-25 17:30

[QUOTE=VictordeHolland;438725]The most abundant dissolved ions in seawater are sodium, chloride, magnesium, sulfate and calcium.

NaCl is common table salt
Sulfates are already extracted from oil and gas in large quantities.
And magnesium and calcium are quite common.
The remaining element are in minute quantities, so you'll need to process large amounts of seawater before extracting useful quantities.[/QUOTE]Yup.

Sul{f,ph}ate is dirt common. That is, lots of variety of dirt contains the SO[sub]4[/sub][sup]-[/sup] ion or its close relatives. Removing SO[sub]2[/sub] from coal-fired power stations is a PITA that the operators would prefer not to have to do but governments in much of the over-developed world require to be done.

Iodine is, AFAIK, the element most likely to be extractable from seawater at a reasonable cost. The use of algae as a pre-processor for the extraction has historical (and AFAIK still is) importance. It's not clear to me how one could plausibly combine algal pre-processing with current desalination technoloogy.

chalsall 2016-07-25 17:35

[QUOTE=VictordeHolland;438725]Sulfates are already extracted from oil and gas in large quantities.[/QUOTE]

A complete tangent, if I may...

Mineral Oil is a by-product of oil and gas production. Cheap as chips. It is put into beauty products and food.

No one here in Bimshire even knows what this is!

I've been trying to source about 20 litres of the stuff to put into our rain water tanks to prevent mosquitoes reproducing. The only supply I've found available retail here is "Johnson's Babyoil" at USD $7 per 500 ml.

Sigh... It can be frustrating living in paradise....

Dubslow 2016-07-26 00:16

[QUOTE=chalsall;438731]
Sigh... It can be frustrating living in paradise....[/QUOTE]

Depends of course on your definition of paradise.

Uncwilly 2016-07-26 01:31

[QUOTE=only_human;438635]There is a desalination plant planned quite near me. This is a local paper.
[URL="http://www.dailybreeze.com/environment-and-nature/20160722/why-south-bay-environmentalists-oppose-west-basins-planned-ocean-water-desalination-plant"]Why South Bay environmentalists oppose West Basin’s planned ocean water desalination plant[/URL][/QUOTE]
I wish to inject some knowledge here.
[LIST=1][*]West Basin has access to several 100 M litres per day of water less saline than the ocean, that is non-potable and currently not used. [URL="http://www.westbasin.org/files/uwmp/section-9-recycled-water.pdf"]Pages 9-1 and 9-2[/URL][*][URL="http://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/RW_DPR_advisorygroup.shtml"]California[/URL] is looking at [URL="http://www.waterworld.com/articles/print/volume-29/issue-9/editorial-features/battling-water-scarcity.html"]allowing for direct reuse of treated water[/URL].[*]The "brine" can be injected in either a currently used 8 km or an unused [URL="http://www.water-technology.net/projects/hyperion/"]11 km pipe[/URL] into the deep offshore water.[*]Using the 8 km pipe would raise the saline content toward the level of seawater.[*]They could use the waste heat of [URL="http://www.dailybreeze.com/government-and-politics/20130912/new-energy-efficient-power-plant-unveiled-in-el-segundo"]several[/URL] [URL="http://www.ladwpnews.com/go/doc/1475/1886746/LADWP-Begins-Rebuilding-Scattergood-Power-Plant-to-Eliminate-Ocean-Water-Cooling-Reduce-Emissions-and-Improve-Reliability"]nearby[/URL] [URL="http://www.dailybreeze.com/business/20160215/redondo-beachs-aes-power-plant-on-the-market"]power[/URL] plants to pre-heat the water to maybe 80C.[/LIST]

chalsall 2016-07-26 01:32

[QUOTE=Dubslow;438745]Depends of course on your definition of paradise.[/QUOTE]

LOL... Having grown up in a part of Canada where -40 degrees was common, it's nice being able to walk around in shorts and saddles in December. Where the only time one encounters water as a solid is in one's drink.

Having said that, I'm reminded of Leonard Cohen's song "Closing Time": "...and the place is dead as Heaven on a Saturday night...".

fivemack 2016-07-27 16:20

[QUOTE=VictordeHolland;438725]The most abundant dissolved ions in seawater are sodium, chloride, magnesium, sulfate and calcium.

NaCl is common table salt
Sulfates are already extracted from oil and gas in large quantities.
And magnesium and calcium are quite common.
The remaining element are in minute quantities, so you'll need to process large amounts of seawater before extracting useful quantities.[/QUOTE]

I believe magnesium has been commercially extracted from sea water during WW2, but that may have stopped once more accessible resources appeared. Bromine is pretty rare in the crust and reasonably common in sea water; strontium is surprisingly common both in the crust and sea water (most common element from that row of the Periodic Table), but little used (it had a big application in high-Z glass when you wanted high-Z glass for the front plates of CRT televisions).

Making sea salt out of sea water is not just a matter of evaporating it to dryness; you do something that looks like fractional crystallisation, because CaCO3 and CaSO4 precipitate before NaCl, and KCl and MgCl2, both of which taste bad, come out after.

xilman 2016-07-27 17:07

[QUOTE=fivemack;438842]I believe magnesium has been commercially extracted from sea water during WW2, but that may have stopped once more accessible resources appeared. Bromine is pretty rare in the crust and reasonably common in sea water; strontium is surprisingly common both in the crust and sea water (most common element from that row of the Periodic Table), but little used (it had a big application in high-Z glass when you wanted high-Z glass for the front plates of CRT televisions).[/QUOTE]Another problem, from the commercial POV, is that there is such a lot of sea water which has already been dried and is now ready for mining in quantity. The UK and Poland are European countries well known for their salt mines. There are, of course, many other such mines around the world.

only_human 2017-06-10 00:32

[URL="https://electrek.co/2017/06/09/tesla-superchargers-solar-battery-grid-elon-musk/"]Tesla plans to disconnect ‘almost all’ Superchargers from the grid and go solar+battery, says Elon Musk[/URL]

The article has a concept picture for Tesla charging stations shaded by giant panels of solar cells. At least in this article he is missing the obvious trick of using the awnings to showcase his solar housing tiles as in tract housing demonstration homes.

[QUOTE]Tesla has been talking about adding solar arrays and batteries to its Supercharger stations ever since announcing the fast-charging network in 2012.

But only half a dozen stations or so out of the over 800 stations ended up getting a solar array.

CEO Elon Musk said that they plan to deploy more battery and solar systems with the upcoming ‘Version 3’ of the Supercharger, but now he went a step further and claimed that “almost all Superchargers will disconnect from the electricity grid.”
Previously, Musk said that Tesla’s new Powerpack and solar arrays will power some Supercharger stations in sunny regions to go off-grid – adding that “the grid won’t be needed for moderate use Superchargers in non-snowy regions.”

While it makes sense to add solar arrays and battery packs, it’s not clear why there would be a need to completely disconnect from the grid, which is often still useful – especially if net metering is available.

Now Musk said on Twitter this morning that they are not only adding solar and batteries to “all Superchargers”, but also that “almost all” Supercharger stations will eventually disconnect from the grid:

[QUOTE]All Superchargers are being converted to solar/battery power. Over time, almost all will disconnect from the electricity grid.

— Elon Musk (@elonmusk) June 9, 2017[/QUOTE]

The comment was in response to someone stating that Tesla’s Superchargers are charging vehicles with dirty electricity from coal plants.

As we recently reported, while partly true, the statement makes no sense if the goal is to be less polluting than gas-powered vehicles.

A recent study of electricity generation concluded that the average electric car in the US now gets the equivalent efficiency of a non-existent 73 mpg gas-powered vehicle after accounting for emission from electricity production.[/QUOTE]

chalsall 2017-06-10 23:33

[QUOTE=only_human;460903]The article has a concept picture for Tesla charging stations shaded by giant panels of solar cells. At least in this article he is missing the obvious trick of using the awnings to showcase his solar housing tiles as in tract housing demonstration homes.[/QUOTE]

Yeah. The usual carbon apologists claim that renewable energy can't be trusted for temporal stability.

What they always (conveniently) forget is electrical storage is always getting better, and we have a finite amount of carbon which can be dug up or pumped out cheaply, and then burned.

CRGreathouse 2017-06-11 00:35

[QUOTE=chalsall;460985]Yeah. The usual carbon apologists claim that renewable energy can't be trusted for temporal stability.

What they always (conveniently) forget is electrical storage is always getting better, and we have a finite amount of carbon which can be dug up or pumped out cheaply, and then burned.[/QUOTE]

The other thing is that we can move more electrical load off-peak if there is sufficient motivation (e.g., differential pricing) to do so.

only_human 2017-06-29 21:48

[QUOTE=CRGreathouse;460990]The other thing is that we can move more electrical load off-peak if there is sufficient motivation (e.g., differential pricing) to do so.[/QUOTE]
Agreed. It would help to use market forces to shift usage patterns.

Currently in California because renewable generation is the easiest to quickly ramp down during oversupply, it is increasingly throttled back to maintain power network stability and California is increasingly paying other states to take some of California's power during oversupply periods:
[URL="http://www.latimes.com/projects/la-fi-electricity-solar/"]California invested heavily in solar power. Now there's so much that other states are sometimes paid to take it[/URL]
[QUOTE]On 14 days during March, Arizona utilities got a gift from California: free solar power.

Well, actually better than free. California produced so much solar power on those days that it paid Arizona to take excess electricity its residents weren’t using to avoid overloading its own power lines.

It happened on eight days in January and nine in February as well. All told, those transactions helped save Arizona electricity customers millions of dollars this year, though grid operators declined to say exactly how much. And California also has paid other states to take power.

The number of days that California dumped its unused solar electricity would have been even higher if the state hadn’t ordered some solar plants to reduce production — even as natural gas power plants, which contribute to greenhouse gas emissions, continued generating electricity.

Solar and wind power production was curtailed a relatively small amount — about 3% in the first quarter of 2017 — but that’s more than double the same period last year. And the surge in solar power could push the number even higher in the future.[/QUOTE]

[QUOTE]When there isn’t demand for all the power the state is producing, CAISO needs to quickly sell the excess to avoid overloading the electricity grid, which can cause blackouts. Basic economics kick in. Oversupply causes prices to fall, even below zero. That’s because Arizona has to curtail its own sources of electricity to take California’s power when it doesn’t really need it, which can cost money. So Arizona will use power from California at times like this only if it has an economic incentive — which means being paid.

In the first two months of this year, CAISO paid to send excess power to other states seven times more often than same period in 2014. “Negative pricing” happened in an average of 18% of all sales, versus about 2.5% in the same period in 2014.

Most “negative pricing” typically has occurred for relatively short periods at midday, when solar production is highest.

But what happened in March shows how the growing supply of solar power could have a much greater impact in the future. The periods of “negative pricing” lasted longer than in the past — often for six hours at a time, and once for eight hours, according to a CAISO report.[/QUOTE]


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