Shuttle Replacement Needs to Become a National Priority!!!

On Mon, 01 Aug 2005 21:28:28 -0700, Richard Morris
wrote (in part):


Ditto for the 3.3 ppb of uranium in seawater. 3.3 ppb is about 10,000
times less concentrated than any ore that has ever been successfully
mined. Gold is a lot more concentrated, and far more valuable, but I
haven't heard of anybody extracting gold from the oceans either. All of
the uranium that has ever been extracted from seawater would probably
fit easily in the palm of your hand. I will believe it can be done,
economically, when somebody builds a pilot plant producing uranium in
useful quantities (tons per year) over a period of one or two decades.
The oceans are not a friendly environment for high-tech equipment, and
it will take a considerable amount of operations to get an idea of the
real costs.

The last paper I saw on extracting uranium from seawater projected a
cost of about $1400 per pound, IIRC. It assumed that the plants would
be anchored in ocean currents to avoid the, apparently, crippling cost
of pumping the water through the filters. It also assumed that we would
burn coal to provide the required process heat. That does not sound
very practical to me.


The Japanese have been looking into this. One cost projection is
$120/pound. See below.

http://www.thegeorgiaguidestones.com/Up_and_Atom.htm

"One possibility for maintaining fission as a major option without
reprocessing is low-cost extraction of uranium from seawater. The uranium
concentration of sea water is low (approximately 3 ppb) but the quantity of
contained uranium is vast - some 4 billion tons (about 700 times more than
known terrestrial resources recoverable at a price of up to $130 per kg). If
half of this resource could ultimately be recovered, it could support for
6,500 years 3,000 GW of nuclear capacity (75 percent capacity factor) based
on next-generation reactors (e.g., high-temperature gas-cooled reactors)
operated on once-through fuel cycles. Research on a process being developed
in Japan suggests that it might be feasible to recover uranium from seawater
at a cost of $120 per lb of U3O8.40 Although this is more than 10 times the
current uranium price, it would contribute just 0.5¢ per kWh to the cost of
electricity for a next-generation reactor operated on a once-through fuel
cycle-equivalent to the fuel cost for an oil-fired power plant burning
$3-a-barrel oil."

40 Nobukawa 1994: H. Nobukawa "Development of a Floating Type System for
Uranium Extraction from Sea Water Using Sea Current and Wave Power," in
Proceedings of the 4th International Offshore and Polar Engineering
Conference (Osaka, Japan: 10-15 April 1994), pp. 294-300.

"Paul F. Dietz" wrote:

Richard Morris wrote:

If we could mine granite and extract the uranium and/or thorium for a
cost that was less than what the energy would sell for at the current
price, somebody would be doing it. If they are, I haven't heard about
it.

Yes, but that's not what I said, or what the argument I was
critiquing required.

I wasn't responding to exactly what you said. And I'd like to see your
analysis of the cost of mining granite for uranium or thorium.

Uranium is currently very cheap, and contributes very little
to the cost of nuclear power. This is why we don't have breeder
reactor programs -- why develop a technology that conserves
uranium when the stuff is so cheap?

Uranium from granite, or from seawater, would be more expensive
than the current market price of uranium. But it would still
be cheap enough that we could afford to mine it and use it
in breeder reactors.

And how likely is the public to accept an energy system dependent on the
production and distribution of hundreds or thousands of tons of
plutonium per year?

Ditto for the 3.3 ppb of uranium in seawater. 3.3 ppb is about 10,000
times less concentrated than any ore that has ever been successfully
mined.

The fact that the stuff is already in solution is a considerable benefit.

Gold is a lot more concentrated,

Wrong. The concentration of gold in seawater is orders of magnitude
lower than that of uranium. Uranium has this ion, uranyl, that
is nicely soluble in oxidizing conditions.

Shouldn't trust the memory at that hour.

The last paper I saw on extracting uranium from seawater projected a
cost of about $1400 per pound, IIRC.

Now realize that a 1 GW(e) breeder reactor would consume roughly
a ton of uranium a year. That $3M/year would contribute $.0005/kWh
to the cost of this electricity.

That's not the point. Even if your numbers are correct, they are
unlikely to come within orders-of-magnitude of that $1,400 cost in the
real world, IMHO.

Have you calculated the number of cubic miles of seawater that would
have to be filtered to supply as much energy as we presently get from
fossil fuels? How much is it going to cost to build and maintain all
the undersea infrastructure to do it?




Paul

George William Herbert wrote:

Richard Morris wrote:
Carbon can be sequestered.

It's already sequestered. Mother Nature has done the job for us, and I
frankly don't see much sense in digging it up and burning it and then
spending a huge amount of money and energy to re-sequester it.

Why not? The net energy gain after sequestration is still
nearly as high as it is without sequestration. The "huge amount"
is significant, but less than is spent to extract it and then
burn it in the first place.

How much less? References?

That we're burying the reaction products again doesn't mean that
the cycle doesn't work. If it's economic to do so, and despite
regular pronouncements of doom and gloom from environmentalists
and luddites, it is, then we can do it and probably should,
if CO2 is a problem.

To point out that we have problems is not the same as saying that we are
"doomed". Can you give me some references of reputable
environmentalists who are saying that we are "doomed"? And I don't know
anyone I would call a "luddite", except maybe Ted Kazinski. People who
want to smash all the machines and go back to a pastoral or
hunter/gatherer lifestyle are certainly a very small minority, even
within the environmental community.

-george william herbert

George William Herbert wrote:

Richard Morris wrote:
The last paper I saw on extracting uranium from seawater projected a
cost of about $1400 per pound, IIRC.

One pound of Uranium contains about 3E13 J of energy.
In BOTE terms, 1E10 Wh. At 10% net efficient conversion,
1E9 Wh, or 1E6 KWh. Or roughly 0.14 cent per KWh.

I currently pay 11 to 13 cents per KWh delivered to my house
on the electrical grid.

Which completely misses the point.

Your economic paranoia is innumerate.

Which has no point.

-george william herbert

"Paul F. Dietz" wrote:

George William Herbert wrote:

Why not? The net energy gain after sequestration is still
nearly as high as it is without sequestration.

In principle, it might even be higher. Mineral carbonation
is net exothermic.

I'd like to see your engineering analysis of the processes and required
infrastructure.

What are you going to carbonate, and how many billions of tons of it do
we have to dispose of per year, just to keep the CO2 concentration from
rising?

Granted, in practice it probably wastes some energy
to overcome slow kinetics. OTOH, it also could produce,
as side streams, enough nickel, chromium, and platinum
group elements to swamp existing markets.

Paul

"Christopher P. Winter" wrote:

On Mon, 01 Aug 2005 21:28:28 -0700, Richard Morris
wrote (in part):


Ditto for the 3.3 ppb of uranium in seawater. 3.3 ppb is about 10,000
times less concentrated than any ore that has ever been successfully
mined. Gold is a lot more concentrated, and far more valuable, but I
haven't heard of anybody extracting gold from the oceans either. All of
the uranium that has ever been extracted from seawater would probably
fit easily in the palm of your hand. I will believe it can be done,
economically, when somebody builds a pilot plant producing uranium in
useful quantities (tons per year) over a period of one or two decades.
The oceans are not a friendly environment for high-tech equipment, and
it will take a considerable amount of operations to get an idea of the
real costs.

The last paper I saw on extracting uranium from seawater projected a
cost of about $1400 per pound, IIRC. It assumed that the plants would
be anchored in ocean currents to avoid the, apparently, crippling cost
of pumping the water through the filters. It also assumed that we would
burn coal to provide the required process heat. That does not sound
very practical to me.


The Japanese have been looking into this. One cost projection is
$120/pound. See below.

http://www.thegeorgiaguidestones.com/Up_and_Atom.htm

"One possibility for maintaining fission as a major option without
reprocessing is low-cost extraction of uranium from seawater. The uranium
concentration of sea water is low (approximately 3 ppb) but the quantity of
contained uranium is vast - some 4 billion tons (about 700 times more than
known terrestrial resources recoverable at a price of up to $130 per kg). If
half of this resource could ultimately be recovered, it could support for
6,500 years 3,000 GW of nuclear capacity (75 percent capacity factor) based
on next-generation reactors (e.g., high-temperature gas-cooled reactors)
operated on once-through fuel cycles. Research on a process being developed
in Japan suggests that it might be feasible to recover uranium from seawater
at a cost of $120 per lb of U3O8.40

I suggest we not count our chickens before they're hatched. Nobody has
yet *demonstrated* a cost within many orders-of-magnitude of that. I'd
like to see your engineering analysis of the infrastructure required to
supply a large part of the worlds energy with uranium from sea water.
And how much does it cost to maintain it?

Although this is more than 10 times the
current uranium price, it would contribute just 0.5¢ per kWh to the cost of
electricity for a next-generation reactor operated on a once-through fuel
cycle-equivalent to the fuel cost for an oil-fired power plant burning
$3-a-barrel oil."

40 Nobukawa 1994: H. Nobukawa "Development of a Floating Type System for
Uranium Extraction from Sea Water Using Sea Current and Wave Power," in
Proceedings of the 4th International Offshore and Polar Engineering
Conference (Osaka, Japan: 10-15 April 1994), pp. 294-300.

Can't find anything more recent?

Richard Morris wrote:
George William Herbert wrote:
Richard Morris wrote:
The last paper I saw on extracting uranium from seawater projected a
cost of about $1400 per pound, IIRC.

One pound of Uranium contains about 3E13 J of energy.
In BOTE terms, 1E10 Wh. At 10% net efficient conversion,
1E9 Wh, or 1E6 KWh. Or roughly 0.14 cent per KWh.

I currently pay 11 to 13 cents per KWh delivered to my house
on the electrical grid.

Which completely misses the point.

Then what was your point?

The point that I inferred, which was that extracting U from
seawater for power generation was uneconomic and/or impractical,
is neatly and completely refuted by "...and yet, such costs are
a trivial ~1% fraction of delivered energy cost today".

Thousands of dollars per pound material cost is perfectly
reasonable modern economic sense for materials that
generate a hundred thousand dollars of revenue per
pound of raw material.

For example, silicon boules ...


-george william herbert

Richard Morris wrote:
Have you calculated the number of cubic miles of seawater that would
have to be filtered to supply as much energy as we presently get from
fossil fuels? How much is it going to cost to build and maintain all
the undersea infrastructure to do it?

Fortunately, the Sun and ocean thermodynamics conspire to cause
ocean currents without our having to lift a finger, and thus
circulation of seawater is a solved problem for most purposes.

At 3.3 ppb in generic seawater, there should be 3.3 tons per
cubic kilometer of water. Even on a once-through, LWR enriched
and 50% tails enrichment process we're talking about something
like 400 kg of usable material per cubic kilometer of seawater.
If half the energy content comes out as usable energy, then
we're talking about 74 terajoules per kg U-235, or about
2 TJ/kg enriched U. Which is 555,000 KWh/kg, or 222 million
KHw per cubic kilometer of seawater.

100 million households in the US. Times 25 KWh/day x 365 days/yr
call it 10,000 KWh/household/year. Double that for work and
transportation maybe? 1 Trillion KWh/year in the US?
So roughly 5,000 cubic km of water effectively filtered,
or at 1% effective recovery 500,000 cu km.

At a current flow rate of 10 kph, 24x365 hrs/year,
that is 87,600 kilometers of flow per year on average.
So a collecting surface area of around 6 square km.
Of perhaps 1mm thick, density 2.0 plastic with the
uranium specific activated resin coating. 12,000 or
so tons of plastic.

Annual plastics production in the US is something
like 50 million tons.


-george william herbert

"Richard Morris" wrote in message
...

George William Herbert wrote:

Richard Morris wrote:

It's already sequestered. Mother Nature has done the
job for us, and I frankly don't see much sense in
digging it up and burning it and then spending a huge
amount of money and energy to re-sequester it.

Why not? The net energy gain after sequestration is still
nearly as high as it is without sequestration. The "huge
amount" is significant, but less than is spent to extract it
and then burn it in the first place.

How much less? References?

This is one I quite liked, while overkill, it has a nice design purity
to it.

http://www.ees.lanl.gov/pdfs/6_zeroemission_52.pdf

Zero emissions coal technology - they are looking at around 93%
efficiency, using the trick of thermo chemical fuel regeneration from
the waste heat.

Pete.

Richard Morris wrote:

I wasn't responding to exactly what you said. And I'd like to see your
analysis of the cost of mining granite for uranium or thorium.

At worst, it would require grinding the rock to very fine powder
and dissolving it in acid, followed by liquid-liquid separation.
This is how uranium is extracted from phosphate ore, for example.
Since the energy content is 20x that of coal, and combustion
of coal releases much more energy that would be required to
melt the same mass of rock, the cost should be acceptable.

I did look up the energy cost of crushing rocks some years back.
It's surprisingly small, even if you go down to dust-sized
particles.


And how likely is the public to accept an energy system dependent on the
production and distribution of hundreds or thousands of tons of
plutonium per year?

Much more likely than accepting freezing and starving in the dark,
if that's the alternative?

Now realize that a 1 GW(e) breeder reactor would consume roughly
a ton of uranium a year. That $3M/year would contribute $.0005/kWh
to the cost of this electricity.


That's not the point. Even if your numbers are correct, they are
unlikely to come within orders-of-magnitude of that $1,400 cost in the
real world, IMHO.

And your basis for this opinion is...? Note that some published
papers given estimates an order of magnitude below your figure.

But let's say they're more expensive than your figure by a factor
of ten. The cost is still affordable.

Have you calculated the number of cubic miles of seawater that would
have to be filtered to supply as much energy as we presently get from
fossil fuels? How much is it going to cost to build and maintain all
the undersea infrastructure to do it?

It's going to cost a lot. Global-scale energy production is
a multi-trillion dollar enterprise, so why should that be surprising?
Are you insisting that any solution also be orders of magnitude
less expensive than what it replaces?

Paul