[Scrub Puller]

Yair . . . I'm showing my ignorance here but I'll ask a Question.
I read that we are running out of this or that . . . high grade iron ore, copper ore, Bauxite, phosphate and so on.

Well where did it all go? It's still here somewhere but mostly in another form which can often be recycled.

As far as I can see the only things that are truly "gone" are fossil fuels which are still here but exist now as a gas . . . as I see it the "work" they did in passing from a liquid or solid to a gas is largely irrelevant in the great scheme of things.

Cheers.

[Loki]

As far as I can see the only things that are truly "gone" are fossil fuels which are still here but exist now as a gas . . . as I see it the "work" they did in passing from a liquid or solid to a gas is largely irrelevant in the great scheme of things.

Yair...the process of combustion tends to make those fossil fuels less useful to perform the work that runs modern industrial society.

Metals degrade through corrosion, or are landfilled, or degrade slowly through use (think brake pads).

Phosphorous is shat out by us and dumped into the rivers, which go out to sea---or it's filtered out in sewage treatment plants and landfilled. Or it runs off from fields, ends up in the rivers, and goes out to sea. Or it's leached into groundwater. Still "there," but no longer useful to run modern industrial society.

Factoid of the day:

Each person excretes between 200 and 1000 grams of phosphorus annually.

http://en.wikipedia.org/wiki/Sewage_tre ... us_removal

[Pops]

Entropy, disorder, fossil mining, dispersion, disruption...

What's going is the easy. High grade ore to low, nuggets to dust, ancient oaks to pine plantations, endless fisheries to grain-fed carp.

Where once oil was in pressurized reservoirs that gushed when we tapped them, now we apply pressure or heat or bulldozers to budge what oilish stuff there is left.

The easily arable land is all in use. So farmers in the US are regularly told by suppliers that yields must increase 75% by 2050 to avoid "hunger". More pesticides, herbicides, fungicides, fertilizers, minerals, irrigation . . . just to stay even.


The problem isn't that it is gone, the problem is it isn't just laying there for the taking.

[Surf]

I have found only two ways elements can be lost:
1. Radioactive elements decay and once they decay they are gone. Today the only ones we have are the ones that decay very slowly such as uranium and thorium. Nuclear reactors can make radioactive elements but most decay rapidly (iodine, cesium)) or can be reused to make more power (plutonium).

2. Gases in the atmosphere can be lost into space. Mars once had a substantial atmosphere. However once it lost it's magnetic field, it lost most of its atmosphere. Earth still has a magnetic field so the loss of atmospheric gases ia very very slow.

Most of the other elements can be recovered but the low cost of rich ore makes the gathering of used materials uneconomic. The EROEI of gathering of used material for reuse is in many cases not known because it is not currently being done.

For example, the planet's oceans contain 1.37 billion cubic kilometers or 4.5 billion tons of uranium. Assuming we could recover half of this resource, this much uranium could support 6,500 years of nuclear capacity.

But we don't have enough uranium on hand to extract it. IE., a lousy eroei.

The most promising method of extracting uranium from seawater has been tested and has achieved a EROEI of 22. This assumes the absorbent is reused 6 times. However the condition of the absorbent after the experiment suggests it can be reused 18 times instead of 6 resulting in a possible EROEI of 66.

Source: http: [url]//spectrum.ieee.org/energy/nuclear/nuclear-fuel-from-the-sea[/url]

[Tanada]

I have found only two ways elements can be lost:
1. Radioactive elements decay and once they decay they are gone. Today the only ones we have are the ones that decay very slowly such as uranium and thorium. Nuclear reactors can make radioactive elements but most decay rapidly (iodine, cesium)) or can be reused to make more power (plutonium).

2. Gases in the atmosphere can be lost into space. Mars once had a substantial atmosphere. However once it lost it's magnetic field, it lost most of its atmosphere. Earth still has a magnetic field so the loss of atmospheric gases ia very very slow.

Most of the other elements can be recovered but the low cost of rich ore makes the gathering of used materials uneconomic. The EROEI of gathering of used material for reuse is in many cases not known because it is not currently being done.

Sounds great, but when you take a concentrated source of elements like a Phosphate mine, manufacture the ore into fertilizer, spread it on fields in a much lower than ore concentration and then have it leach away in urine and as irrigation/rainfall wash water it ends up in streams, rivers and eventually the ocean where it is diluted to extremely low concentrations compared to the ore from which it was mined.

Sure all the Phosphorus you mined still exists, but you took it from a highly concentrated ore to a liquid dispersed out through the volume of the world oceans. Using it again involves capturing it from the very dilute form, and that takes either a lot of time for nature to work, or a lot of energy for technology to work.

The same can be said of every water soluable element you can find, dissolve it in water and it will disperse.

[Lore]

Think, everyone who was ever born and lived on the planet is still here, why can't we talk with them?

[Surf]

But anyway apparently mined uranium returns over 400:1 units of energy. And that seems barely economic, given the dearth of new reactor installation.[quote][/quote]

EROEI is calculated from Watts in watts out or BTU in BTU out. Cost is not part of EROEI calculation. Lan, legal, labo, safety, security, procurement, and wast management all affect the cost of a reactor and can make a reactor uneconomic even if the EROEI is good.

Code: Select all

Sure all the Phosphorus you mined still exists, but you took it from a highly concentrated ore to a liquid dispersed out through the volume of the world oceans. Using it again involves capturing it from the very dilute form, and that takes either a lot of time for nature to work, or a lot of energy for technology to work.

Yes phosphorus is highly diluted in the sea. but plants (sea weed) manage to extract it from the sea water and use it to grow. In fact Sea weed can grow very rapidly if tIf the temperature and good and enough light is present growth can be very fast. People have been harvesting seaweed for use as food and fertilizer for centuries. Seaweed can also be used to make fuel. Yes the minerals in sea water are highly dilute but that doesn't nean a lot of energy, time, or equipment is needed to extract it.

[Loki]

Yes phosphorus is highly diluted in the sea. but plants (sea weed) manage to extract it from the sea water and use it to grow. In fact Sea weed can grow very rapidly if tIf the temperature and good and enough light is present growth can be very fast. People have been harvesting seaweed for use as food and fertilizer for centuries. Seaweed can also be used to make fuel. Yes the minerals in sea water are highly dilute but that doesn't nean a lot of energy, time, or equipment is needed to extract it.

I'd appreciate evidence for the assertion that we can mine phosphorous from the ocean to provide for our industrial agricultural needs. Almost all current phosphorous comes from phosphate rock and guano, which are projected to peak in the next couple decades.

Just because there's a lot of phosphorous "out there" doesn't mean it'll ever be commercially viable to mine it.

[Pops]

Note the Quote of the Day:
"peaking is the result of declining production rates, not declining reserves"

The current surplus [of everything] is the result of extracting highly concentrated, previously untouched resources. Advances in technology have to this point increased the rate at which we can extract what we want from those pockets.

I think we are entering the phase where advancing technology and energy will be spent just to keep up the rate of extraction constant. I don't think anyone would argue that harvesting kelp for P is as efficient as mining it from concentrated deposits. Efficiency is the key here; the low effort required to get those concentrated goodies, the more effort can be devoted to producing other goodies.

Interestingly, better technology has also increased our ability to identify less concentrated resources, say light tight or ultra deep oil, that may never be usable simply because they are to expensive to obtain.

Just because I know there is a $15M iPhone out there doesn't mean Santa is gonna bring it.

[Lore]

I'm selling interest in this mountain of gold I've discovered on the moon. Any takers?

[Subjectivist]

I'm selling interest in this mountain of gold I've discovered on the moon. Any takers?

Depends, how much does a share cost and how many are you selling? ROFL!

[kuidaskassikaeb]

I found this it's kind of cool

Urban mining: Glittering pavements and underworld treasure

http://inspirebetter.blogspot.com/2013/06/urban-mining-glittering-pavements-and.html

Basically urban dust has concentration of platinum group elements as high as the ores.

As for phosphorous

Phosphorus comprises about 0.1% by mass of the average rock, and consequently the Earth's supply is vast, although dilute.[9]

So we'll never run out of phosphate either. As long as we have energy we won't run out of anything else. One thing that was special about fossil fuels is that they have been the substitute for all these high grade ores, good soil etc. Fossil fuel energy has been the go to, when you run out of this or that. That is why running out of fossil fuels was so scary. And all those users are counting on them to run their air conditioners on an unlivable planet.