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Old 21st May 2019, 07:09 AM   #161
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Originally Posted by Kestrel View Post

Similar plants in the United States have equipment, plans and staff training to deal with that scenario. This was not part of the original design. It was a safety improvement that was done later.

Newer modular reactor designs with passive cooling systems don’t have the problem.
At the plant I worked at in the US, there were no contingency plans for the loss of the emergency on site power.

There were three of them for a total of 15 MW, housed behind three foot thick concrete walls, and the fuel bunker inside another concrete wall.

Fukishima were all pre TMI plants with no post TMI modifications to make them safer.

No reactor core isolation cooling system, no hydrogen recombiners etc.
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Old 21st May 2019, 07:14 AM   #162
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Originally Posted by lomiller View Post
To me that’s why I see nuclear as a transitionary technology not the final landing spot.
But transitionary towards what?
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Old 22nd May 2019, 11:49 AM   #163
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Originally Posted by Belz... View Post
But transitionary towards what?
Renewables. Contrary to what a lot of people seem to believe there isn’t an issue in running our using renewables, the issue is that doing so means we have to change things we’ve become accustomed to and some people do not deal well with change.

Eg. When running a manufacturing plant, for example, it’s “more efficient” to keep the equipment as heavily utilized as possible, and if it there isn’t enough demand run in cycles of 100% utilization and 0% utilization. We’ve then gone ahead and built our cities and societies around this type of schedule. The problem is that this is only more efficient if we ignore the costs of having energy available to run these plants like this.


It’s not like this is the only possible way to produce goods it’s just what we are used to dong it this way because it’s what markets have favored due to the hidden subsides of free CO2 emissions. We are still going to need time to adapt to how/when/where me make things, hence the need for transitionary power sources.

Fortunately making things is a shrinking part of our economy. Most jobs these days do not actually require us to travel to some centralized location. Working remotely from home is perfectly viable for an increasing number of jobs, but we still congregate in centralized offices and move people long distances to do so, again in large part because we subsidize the energy costs involved. We also make a lot of cheep disposable products rather then using better made longer lasting ones. Once again, the subsidizing of energy costs is a major reason, but it’s something we have become accustomed to not something we must do.

We need energy with less variation in production in the short term because our cities and society have adapted to this type of environment. Without externalities free market are actually very good at adapting to resource arability and would certainly adapt to different conditions, just not overnight. Likewise how we design cities and how we move in our cities can adapt, but again not instantly.
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Old 27th May 2019, 05:37 PM   #164
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Originally Posted by lomiller View Post
Renewables. Contrary to what a lot of people seem to believe there isn’t an issue in running our using renewables, the issue is that doing so means we have to change things we’ve become accustomed to and some people do not deal well with change.

Eg. When running a manufacturing plant, for example, it’s “more efficient” to keep the equipment as heavily utilized as possible, and if it there isn’t enough demand run in cycles of 100% utilization and 0% utilization. We’ve then gone ahead and built our cities and societies around this type of schedule. The problem is that this is only more efficient if we ignore the costs of having energy available to run these plants like this.


It’s not like this is the only possible way to produce goods it’s just what we are used to dong it this way because it’s what markets have favored due to the hidden subsides of free CO2 emissions. We are still going to need time to adapt to how/when/where me make things, hence the need for transitionary power sources.

Fortunately making things is a shrinking part of our economy. Most jobs these days do not actually require us to travel to some centralized location. Working remotely from home is perfectly viable for an increasing number of jobs, but we still congregate in centralized offices and move people long distances to do so, again in large part because we subsidize the energy costs involved. We also make a lot of cheep disposable products rather then using better made longer lasting ones. Once again, the subsidizing of energy costs is a major reason, but it’s something we have become accustomed to not something we must do.

We need energy with less variation in production in the short term because our cities and society have adapted to this type of environment. Without externalities free market are actually very good at adapting to resource arability and would certainly adapt to different conditions, just not overnight. Likewise how we design cities and how we move in our cities can adapt, but again not instantly.
NONSENSE. While automation has reduced the number of people working in manufacturing, it is still very important to the economy and our lives. The WORLD in fact manufacturers more now than EVER and that will in fact skyrocket as the developing world starts to consume as much as the west . To say different is a demonstration of ignorance.

A dependable baseload of cheap power is needed to rise half the planet out of poverty. While I am not a fan of how nuclear power has been implemented, the truth is a nuclear power done right could power the world for thousands of years.

The problem is we've been using nuclear power the same way. Solid fuel using pressurized water. What we need are idiot proof walk away safe reactors and the 1950s Submarine approach has inherent safety problems. Most of these can be addressed by continued development of molten salt reactors.
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Old 28th May 2019, 12:21 AM   #165
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Originally Posted by lomiller View Post
We also make a lot of cheep disposable products rather then using better made longer lasting ones. Once again, the subsidizing of energy costs is a major reason, but it’s something we have become accustomed to not something we must do.
Is that true? In some cases cheap disposable products have a lower energy cost than the energy cost of better made longer lasting ones.

For instance, this 2018 danish study suggests that reusable cotton shopping bags need to be used 7100 times in order to have less environmental impact than using disposable plastic bags.

If only climate change is being considered that number drops to 52, which is much more reasonable.
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Old 28th May 2019, 01:53 PM   #166
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Originally Posted by acbytesla View Post
It is a problem, but comparatively it is a minor and over-exaggerated one. Especially if molten salt breeder reactors are developed which can burn up most of that waste.
The British design relied on using their existing accumulated stockpile of nuclear waste as fuel. Thus, the fuel was effectively free (and the Brits have a lot of it)

You can read about it.

Interesting quote from the above...

Quote:
If the programme had continued and a commercial MSFR had started supplying the grid in 1995, removing the need for 2.5GWe of coal-fired power, this would have prevented 340 million tonnes of CO2 emissions — or nearly three quarters of the UK’s entire annual CO2 emissions in 2013. A single MSFR would have reduced UK carbon emissions by approximately 5% a year, every year, since 1995! A fleet of six MSFRs could have completely replaced coal in the UK’s energy mix.
That simply illustrates where the world could be in the race against carbon.

So why are we not even close?

Surely the eco-nuts should be supporting this, right?

Wrong. They are ideologically opposed to nuclear. This was actually a principled, moral and rationally justified stance at the time it arose. But that time is not this time and the eco-nuts cannot seem to find their way out of an ideology that has become entrenched over decades. So entrenched that the automatic reaction to anything containing the words "nuclear reactor" is automatically bad, never mind that the technology and process and waste of MSR is entirely different.

This puts them in a fork of an uncomfortable type. They could lobby for a technology that would wipe out vast swathes of carbon emissions instantly, but they can't because their ideology won't let them. It has gone beyond ideology into fervent religious faith like proportions.

I've been quietly saying nuclear was the way to go for some years. Quietly, because nobody listens. Sure I started loudly, but the sheer inertia beat me.

The objection to nuclear has gone from rational, to ideological, to irrational. And you cannot reason anyone out of an irrational position.

So, YES, acbytesla, I am fully aboard with urgently pressing forward with MSRs and similar tech.

Anyone who isn't simply hasn't looked at the facts.
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Old 28th May 2019, 02:22 PM   #167
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Originally Posted by abaddon View Post
The British design relied on using their existing accumulated stockpile of nuclear waste as fuel. Thus, the fuel was effectively free (and the Brits have a lot of it)

You can read about it.

Interesting quote from the above...



That simply illustrates where the world could be in the race against carbon.

So why are we not even close?

Surely the eco-nuts should be supporting this, right?

Wrong. They are ideologically opposed to nuclear. This was actually a principled, moral and rationally justified stance at the time it arose. But that time is not this time and the eco-nuts cannot seem to find their way out of an ideology that has become entrenched over decades. So entrenched that the automatic reaction to anything containing the words "nuclear reactor" is automatically bad, never mind that the technology and process and waste of MSR is entirely different.

This puts them in a fork of an uncomfortable type. They could lobby for a technology that would wipe out vast swathes of carbon emissions instantly, but they can't because their ideology won't let them. It has gone beyond ideology into fervent religious faith like proportions.

I've been quietly saying nuclear was the way to go for some years. Quietly, because nobody listens. Sure I started loudly, but the sheer inertia beat me.

The objection to nuclear has gone from rational, to ideological, to irrational. And you cannot reason anyone out of an irrational position.

So, YES, acbytesla, I am fully aboard with urgently pressing forward with MSRs and similar tech.

Anyone who isn't simply hasn't looked at the facts.


I am in complete agreement.
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Old 29th May 2019, 07:52 AM   #168
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Originally Posted by lomiller View Post
Renewables. Contrary to what a lot of people seem to believe there isn’t an issue in running our using renewables,
And, to complicate matters, nuclear is renewable. The amount of uranium released into the world's oceans due to weathering of rocks is enormous.

Experiments with extracting uranium from seawater indicate a projected cost for yellowcake about twice that of current prices. OK, this is almost certainly over-optimistic - pioneer estimates always err that way. Nonetheless, given the small fraction of operating cost accounted for by fuel, it seems clear that the process ought to economically feasible for even very modest increases in power costs. Furthermore, the oceanic footprint required for the separation process is remarkably small - a few square kilometers per gW-yr. Given the constant nature of ocean currents, the amount of seawater which passes through a square km aperture is enormous, and the extraction apparatus essentially looks like enormous kelp beds and does not grossly impact marine life.
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Old 29th May 2019, 07:55 AM   #169
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Originally Posted by lomiller View Post
Renewables.
A fool's errand. No one's going to lower their standard of living to use inferior methods of energy generation unless the choice is forced upon them, including myself.

Solar and wind simply can't replace coal, hydro or nuclear. At best they can supplement a grid nicely, but what's your bedrock? You can stay with coal and hydro doesn't work everywhere.

No points for guessing which one remains.

Quote:
Fortunately making things is a shrinking part of our economy.
...what?
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Old 29th May 2019, 12:09 PM   #170
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Originally Posted by WhatRoughBeast View Post
And, to complicate matters, nuclear is renewable. The amount of uranium released into the world's oceans due to weathering of rocks is enormous.

Experiments with extracting uranium from seawater indicate a projected cost for yellowcake about twice that of current prices. OK, this is almost certainly over-optimistic - pioneer estimates always err that way. Nonetheless, given the small fraction of operating cost accounted for by fuel, it seems clear that the process ought to economically feasible for even very modest increases in power costs. Furthermore, the oceanic footprint required for the separation process is remarkably small - a few square kilometers per gW-yr. Given the constant nature of ocean currents, the amount of seawater which passes through a square km aperture is enormous, and the extraction apparatus essentially looks like enormous kelp beds and does not grossly impact marine life.
This is true, but what also is true is today's reactors use only a few percent of the uranium before they call it spent fuel.

This is the problem with solid fuel. The uranium pellets which are a uranium ceramic mixture swell and crack and become contaminated with fission products until they become unusable. But 97 to 99 percent of the uranium goes unused. This isn't a problem with molten salt as the the gases that crack the solid fuel just bubble out of the salt mixture. There appears to be no reason that any fissile material cannot be used up in salt mixture whether that be U235, U233 or Plutonium.

There is no shortage of uranium although extraction methods could become more expensive. But fuel costs is a minor issue.

The big problem with nuclear is the expense of building today's reactors. The need to build safe reactors is the crux of the problem. It is what makes them economically uncompetitive. As long as reactors are fighting what is occurs naturally by using solid fuel and pressurized water as the moderator and coolant, I'm afraid nuclear power will never be cost competitive with fossil fuels.
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Old 29th May 2019, 12:44 PM   #171
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Originally Posted by acbytesla View Post
The secondary or tertiary circuits are not in contact with radioactive elements. Yes a steam pipe in that circuit could burst due to pressure but I'm guessing they would have pressure relief valves.

I don't know. But I don't really believe this is a major issue.
I'm assuming you mean where the designs would continue to use a solid fuel and have salt circulate around a solid fuel. The answer is some do.

Yes. And that is a big feature in most of the designs. A traditional reactor requires periodic shutdowns to refuel. An MSR allows you to add fuel on a regular basis.
These are excellent questions that I don't know the answers to at this moment. Fission would be what keeps it hot but I don't know how they start it exactly.

There doesn't seem to be much of a concern of it becoming aerosolized. But Tritium has been mentioned as a potential issue with FLIBE. But a form of it was used in the MSRE and tritium wasn't a substantial problem. You seem to understand this very well.

But this was just one salt mixture. I think they like it because it has a low melting point.
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I've watched almost every video that has been published about Molten Salt Reactors and Thorium as well as reading as much as possible about it. I've been looking for information that busts this balloon. But I haven't heard it yet. Below is the 1970s Oak Ridge Laboratory documentary on the Molten Salt Reactor Experiment. It's pretty technical.
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There is at least 20 new startups working on using molten salt in some way with future reactors. Using the thorium fuel cycle seems be highly desirable as well. But a lot of these companies want to just start with molten salt and work their way into using Thorium.
A bit of a late response, and to only one point (for now).

In an MSR in which the fuel is mixed with, or is, the salt, if the primary loop is breached, there’s nothing to stop it flowing to wherever it can go, right?

Last edited by JeanTate; 29th May 2019 at 02:28 PM. Reason: fixed a typo (should be "an")
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Old 29th May 2019, 12:56 PM   #172
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Originally Posted by acbytesla View Post
NONSENSE. While automation has reduced the number of people working in manufacturing, it is still very important to the economy and our lives. The WORLD in fact manufacturers more now than EVER and that will in fact skyrocket as the developing world starts to consume as much as the west . To say different is a demonstration of ignorance.

A dependable baseload of cheap power is needed to rise half the planet out of poverty. While I am not a fan of how nuclear power has been implemented, the truth is a nuclear power done right could power the world for thousands of years.

The problem is we've been using nuclear power the same way. Solid fuel using pressurized water. What we need are idiot proof walk away safe reactors and the 1950s Submarine approach has inherent safety problems. Most of these can be addressed by continued development of molten salt reactors.
There is a really interesting article in the Graphic detail section of the May 25th 2019 issue of The Economist (sorry, can’t post a link).

A high level summary might be that the later GDP per person rises, the lower the CO2 emissions per person.

So what lomiller wrote could be quite accurate ...
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Old 29th May 2019, 12:58 PM   #173
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Originally Posted by abaddon View Post
The British design relied on using their existing accumulated stockpile of nuclear waste as fuel. Thus, the fuel was effectively free (and the Brits have a lot of it)

You can read about it.

Interesting quote from the above...



That simply illustrates where the world could be in the race against carbon.

So why are we not even close?

Surely the eco-nuts should be supporting this, right?

Wrong. They are ideologically opposed to nuclear. This was actually a principled, moral and rationally justified stance at the time it arose. But that time is not this time and the eco-nuts cannot seem to find their way out of an ideology that has become entrenched over decades. So entrenched that the automatic reaction to anything containing the words "nuclear reactor" is automatically bad, never mind that the technology and process and waste of MSR is entirely different.

This puts them in a fork of an uncomfortable type. They could lobby for a technology that would wipe out vast swathes of carbon emissions instantly, but they can't because their ideology won't let them. It has gone beyond ideology into fervent religious faith like proportions.

I've been quietly saying nuclear was the way to go for some years. Quietly, because nobody listens. Sure I started loudly, but the sheer inertia beat me.

The objection to nuclear has gone from rational, to ideological, to irrational. And you cannot reason anyone out of an irrational position.

So, YES, acbytesla, I am fully aboard with urgently pressing forward with MSRs and similar tech.

Anyone who isn't simply hasn't looked at the facts.
Are there any “eco-nuts” posting in this thread?
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Old 29th May 2019, 02:31 PM   #174
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Originally Posted by JeanTate View Post
A bit of a late response, and to only one point (for now).

In a MSR in which the fuel is mixed with, or is, the salt, if the primary loop is breached, there’s nothing to stop it flowing to wherever it can go, right?
Until it freezes ...which it will. Imagine liquid water spilling inside a room that is 175 below zero. It's not going to remain in its liquid state very long.

And the risk of the primary loop being breached is far less because of the lack of pressure.
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Old 29th May 2019, 02:38 PM   #175
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Originally Posted by JeanTate View Post
There is a really interesting article in the Graphic detail section of the May 25th 2019 issue of The Economist (sorry, can’t post a link).

A high level summary might be that the later GDP per person rises, the lower the CO2 emissions per person.

So what lomiller wrote could be quite accurate ...
Sorry, but this sentence did not make much sense to me. Ill look for the article though.
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Old 29th May 2019, 02:38 PM   #176
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Originally Posted by acbytesla View Post
Until it freezes ...which it will.
Why would it?

It is hot, in part, because the fuel is fissioning ... it doesn't magically stop fissioning if it escapes a pipe.

It is also hot because some fission products emit highly energetic alphas, betas, and gammas. It takes quite a while for such short-lived nuclides to decay to somewhat more stable species.

Quote:
Imagine liquid water spilling inside a room that is 175 below zero. It's not going to remain in its liquid state very long.
It will certainly remain liquid if it contains dissolved, highly radioactive salts, for example.

Quote:
And the risk of the primary loop being breached is far less because of the lack of pressure.
And how, may I ask, is this relevant?
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Old 29th May 2019, 03:39 PM   #177
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Originally Posted by JeanTate View Post
Why would it?
It is hot, in part, because the fuel is fissioning ... it doesn't magically stop fissioning if it escapes a pipe.
Fission stops outside the reactor. The reactor is designed with a neutron slowing moderator such as graphite. It also contains neutron reflecting materials. Those neutrons would be lost to other elements.

Originally Posted by JeanTate View Post

It is also hot because some fission products emit highly energetic alphas, betas, and gammas. It takes quite a while for such short-lived nuclides to decay to somewhat more stable species.

It will certainly remain liquid if it contains dissolved, highly radioactive salts, for example.

Radioactivity do
And how, may I ask, is this relevant?
This is the inherent safety feature of a molten salt reactor. Unlike radioactive water that flashes to steam when depressurized, liquid or molten salt freezes and becomes a solid outside of the reactor. Lithium Fluoride solidifies at 500 C.
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Old 29th May 2019, 03:57 PM   #178
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Thanks for your response.

Originally Posted by acbytesla View Post
Fission stops outside the reactor. The reactor is designed with a neutron slowing moderator such as graphite. It also contains neutron reflecting materials. Those neutrons would be lost to other elements.
Hmm ... so the molten mixture (various salts, fission products, etc) contain no moderating or reflecting components?

Quote:
Originally Posted by JeanTate
It is also hot because some fission products emit highly energetic alphas, betas, and gammas. It takes quite a while for such short-lived nuclides to decay to somewhat more stable species.

It will certainly remain liquid if it contains dissolved, highly radioactive salts, for example.

Radioactivity do
And how, may I ask, is this relevant?
This is the inherent safety feature of a molten salt reactor. Unlike radioactive water that flashes to steam when depressurized, liquid or molten salt freezes and becomes a solid outside of the reactor. Lithium Fluoride solidifies at 500 C.
Sorry but that does not address my question, nor the fact that water which contains highly radioactive dissolved salts will remain liquid in a "sea level" atmospheric environment that is at a temperature some hundreds of K below 0K ...
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Old 29th May 2019, 04:32 PM   #179
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Originally Posted by JeanTate View Post
Thanks for your response.

Hmm ... so the molten mixture (various salts, fission products, etc) contain no moderating or reflecting components?
Right.

Originally Posted by JeanTate View Post

Sorry but that does not address my question, nor the fact that water which contains highly radioactive dissolved salts will remain liquid in a "sea level" atmospheric environment that is at a temperature some hundreds of K below 0K ...
I guess I don't understand your question. And I'm fairly sure your mistaken. There is NO WATER in a Molten Salt Reactor except possibly in a secondary non radioactive coolant.

The fuel/primary molten salt coolant during fission is around 600 to 1000C.(This varies on the design, the specific chemistry of the salt and the amount of reaction taking place) Higher concentrations of fuel leads to more criticality whereas hotter temperatures causes the salt to expand reducing criticality.

Without criticality, one is dealing with decay heat and then the question is simply about how quickly that heat is lost to the surrounding environment. But again the beauty the molten salt does not disperse to the atmosphere and is limited by how far the liquid salt can travel before becoming a solid.
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Old 29th May 2019, 04:47 PM   #180
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Thanks again.

Originally Posted by acbytesla View Post
Right.
Source?

Quote:

I guess I don't understand your question. And I'm fairly sure your mistaken. There is NO WATER in a Molten Salt Reactor except possibly in a secondary non radioactive coolant.
Um, it was you who introduced water, not me.

I asked/stated that the molten mixture will not freeze if it escapes its confines because of the highly radioactive fission products contained in it (at least, not quickly anyway).

This is the (well one) point you have not yet addressed (as far as I can see; apologies if i missed it).

Quote:
The fuel/primary molten salt coolant during fission is around 600 to 1000C.(This varies on the design, the specific chemistry of the salt and the amount of reaction taking place) Higher concentrations of fuel leads to more criticality whereas hotter temperatures causes the salt to expand reducing criticality.

Without criticality, one is dealing with decay heat and then the question is simply about how quickly that heat is lost to the surrounding environment. But again the beauty the molten salt does not disperse to the atmosphere and is limited by how far the liquid salt can travel before becoming a solid.
Well, sorta. If, for example, the primary loop fails inside the heat exchanger, it comes in contact with liquid water (in some designs anyway), which can surely lead to many possible nasty consequences, including the dispersal of highly radioactive material into the atmosphere. Not to mention something carelessly (and very much against SOP!) left on the floor which gets flooded with molten primary loop liquid ...
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Old 29th May 2019, 05:23 PM   #181
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Originally Posted by JeanTate View Post
Thanks again.



Source?



Um, it was you who introduced water, not me.

I asked/stated that the molten mixture will not freeze if it escapes its confines because of the highly radioactive fission products contained in it (at least, not quickly anyway).

This is the (well one) point you have not yet addressed (as far as I can see; apologies if i missed it).

Well, sorta. If, for example, the primary loop fails inside the heat exchanger, it comes in contact with liquid water (in some designs anyway), which can surely lead to many possible nasty consequences, including the dispersal of highly radioactive material into the atmosphere. Not to mention something carelessly (and very much against SOP!) left on the floor which gets flooded with molten primary loop liquid ...
All, I can say is not really. My studies have lead me to believe that the molten salt would not remain liquid very long outside the reactor. Also, fluorides are extremely stable and even if they mixed with water, there is little danger of nasty reactions.

But here's the problem Jean. It's impossible to say all this with 100% certainty. Most of these reactors are paper reactors and they all differ from each other in so many ways.

Here are a couple of links. There are also tons more info out there on this subject.

http://www.world-nuclear.org/informa...-reactors.aspx

https://en.m.wikipedia.org/wiki/Molten_salt_reactor
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Old 29th May 2019, 05:29 PM   #182
JeanTate
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Again, thanks.

Originally Posted by acbytesla View Post
All, I can say is not really. My studies have lead me to believe that the molten salt would not remain liquid very long outside the reactor. Also, fluorides are extremely stable and even if they mixed with water, there is little danger of nasty reactions.
Nothing to complain about on that. Other than to say that, for me here in this ISF board, I often expect something a lot, um, meatier.

Quote:

But here's the problem Jean. It's impossible to say all this with 100% certainty. Most of these reactors are paper reactors and they all differ from each other in so many ways.

<snip>
Indeed.

Maybe we'll learn more about the risks etc of such reactors after several hundred have been in operation for a decade or three, and the stupidity (let me leave it at that) of an operator or two manifests itself ...
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Old 29th May 2019, 06:01 PM   #183
acbytesla
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Originally Posted by JeanTate View Post
Again, thanks.

Nothing to complain about on that. Other than to say that, for me here in this ISF board, I often expect something a lot, um, meatier.

Indeed.

Maybe we'll learn more about the risks etc of such reactors after several hundred have been in operation for a decade or three, and the stupidity (let me leave it at that) of an operator or two manifests itself ...
I think you're being a bit unfair.

I'm not saying everything is perfect with these designs and they are entirely safe. Any time one is working with radioactive materials an element of danger is involved. That said, the danger is significantly limited in comparison to present day reactors that involve pressures of 150 atmospheres and the explosive issues with hydrogen. There simply is no possibility of radioactive clouds circling the earth. No requirement for a 15 mile evacuation zone. When perfected, they should be a 100 times safer and a fraction of the cost.

Thanks for the conversation.
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Old 29th May 2019, 06:22 PM   #184
JeanTate
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Originally Posted by acbytesla View Post
I think your being a bit unfair.

I'm not saying everything is perfect with these designs and they are entirely safe. Any time one is working with radioactive materials an element of danger is involved. That said, the danger is significantly limited in comparison to present day reactors that involve pressures of 150 atmospheres and the explosive issues with hydrogen. There simply is no possibility of radioactive clouds circling the earth. No requirement for a 15 mile evacuation zone. When perfected, they should be a 100 times safer and a fraction of the costs.

Thanks for the conversation.
A bit unfair?

I don’t think so. What you wrote may be described with many terms; I’ll use “apples and oranges”.

A more “apples to apples” comparison might be with the very best, safest, contemporary designs for non-MSR power reactors.

And thank you too.
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Old 29th May 2019, 06:55 PM   #185
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Originally Posted by JeanTate View Post
A bit unfair?

I don’t think so. What you wrote may be described with many terms; I’ll use “apples and oranges”.

A more “apples to apples” comparison might be with the very best, safest, contemporary designs for non-MSR power reactors.

And thank you too.
That's the point. It is apples and oranges. It's nuclear fission done an entirely different way. However, I get your point. But given time considerations, I don't have the bandwidth or complete understanding of the 6 different Generation IV reactors all of which have variants. Still, there is pretty much a consensus that molten salt reactor is inherently safer than the others. That said, safety is only one consideration.
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Old 29th May 2019, 07:19 PM   #186
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Originally Posted by acbytesla View Post
That's the point. It is apples and oranges. It's nuclear fission done an entirely different way. However, I get your point. But given time considerations, I don't have the bandwidth or complete understanding of the 6 different Generation IV reactors all of which have variants. Still, there is pretty much a consensus that molten salt reactor is inherently safer than the others. That said, safety is only one consideration.
I concur.

There’s cost (of many kinds), regulation (oh so much built in to just one word!), disposal of “spent fuel”, nimby-ism, ...
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Old 29th May 2019, 08:50 PM   #187
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Originally Posted by JeanTate View Post
I concur.

There’s cost (of many kinds), regulation (oh so much built in to just one word!), disposal of “spent fuel”, nimby-ism, ...
My view is that the public is ignorant and irrationally afraid. Few people understand that nuclear power can be done a hundred different ways and they treat them as a monolith. Nuclear is nuclear in their minds. It's all the same. But as we've discussed, it's not.

Regulations are required, but I view it a bit like insurance. There is such a thing as too much.
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Old 30th May 2019, 06:38 AM   #188
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Originally Posted by acbytesla View Post
My view is that the public is ignorant and irrationally afraid. Few people understand that nuclear power can be done a hundred different ways and they treat them as a monolith. Nuclear is nuclear in their minds. It's all the same. But as we've discussed, it's not.

Regulations are required, but I view it a bit like insurance. There is such a thing as too much.
And with this, I think we're pretty done here, in this the SMM&T board of the ISF ... there are other boards far more suited to discussion of costs, regulations, nimby-ism, etc.

But perhaps a discussion of "disposal of spent fuel" (and cleanup after disasters) belongs here?
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Old 30th May 2019, 07:22 AM   #189
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Originally Posted by JeanTate View Post
And with this, I think we're pretty done here, in this the SMM&T board of the ISF ... there are other boards far more suited to discussion of costs, regulations, nimby-ism, etc.

But perhaps a discussion of "disposal of spent fuel" (and cleanup after disasters) belongs here?
Frankly, I thought this belonged in politics which is where I started it but the mods moved it here. Nuclear power developed into it's present state because of the military requirements, politics and entrenchment. Almost all of today's designs have their roots in the Nautilus.

There have always been different approaches to doing nuclear power. The first reactor that generated electricity was in fact a fast breeder reactor. The molten salt reactor was originally designed to power an aircraft indefinitely in the air although that was never really practical.
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Old 1st June 2019, 06:54 AM   #190
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Originally Posted by JeanTate View Post

Nothing to complain about on that. Other than to say that, for me here in this ISF board, I often expect something a lot, um, meatier.
Thorium Molten-Salt Nuclear Energy Synergetics That meaty enough?

I am not a nuclear physicist, so don't ask me to explain details, but I think acbytesla was telling you right. The advantage of TSR is that in the event of a worst case scenario "meltdown", the material turns into solid rock which is easily isolated and removed from the environment.

Also I am told we can actually use radioactive waste as fuel and iirc end up with something that is ~600 times smaller by volume and dangerous only ~300 years instead of tens of thousands of years. It's a huge improvement.
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Old 1st June 2019, 08:50 AM   #191
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Thanks RBF.

Originally Posted by Red Baron Farms View Post
Thorium Molten-Salt Nuclear Energy Synergetics That meaty enough?

I am not a nuclear physicist, so don't ask me to explain details, but I think acbytesla was telling you right. The advantage of TSR is that in the event of a worst case scenario "meltdown", the material turns into solid rock which is easily isolated and removed from the environment.

Also I am told we can actually use radioactive waste as fuel and iirc end up with something that is ~600 times smaller by volume and dangerous only ~300 years instead of tens of thousands of years. It's a huge improvement.
For me, this thread has gone about as far as it can, here in the SMM&T board.

On paper, and in some limited, small-scale tests, some molten salt reactors - for power production when they grow up - show great promise. In many respects. In several different ways (and FWIW, so do some contemporary non-MSR designs).

However, unless and until a full-scale prototype is built, and has some serious testing time under its belt, that promise will remain just that.

AFAICS, the main barriers (let's say) to progress have little to do with nuclear physics, chemistry, basic engineering, etc, and much more to do with non-SMM&T factors like cost, regulation, and nimby-ism.
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Old 1st June 2019, 12:38 PM   #192
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Originally Posted by JeanTate View Post
Thanks RBF.

For me, this thread has gone about as far as it can, here in the SMM&T board.

On paper, and in some limited, small-scale tests, some molten salt reactors - for power production when they grow up - show great promise. In many respects. In several different ways (and FWIW, so do some contemporary non-MSR designs).

However, unless and until a full-scale prototype is built, and has some serious testing time under its belt, that promise will remain just that.

AFAICS, the main barriers (let's say) to progress have little to do with nuclear physics, chemistry, basic engineering, etc, and much more to do with non-SMM&T factors like cost, regulation, and nimby-ism.
Check out this recent article in Forbes magazine. I love Thorcon's approach.

One such reactor is ThorCon, a fission reactor with a liquid molten salt fuel containing thorium+uranium. A full-scale 500 MW ThorCon prototype should be able to be built and operating within four years.

"horCon takes a different tack on manufacturing. It would be completely manufactured in 150 to 500 ton blocks in a shipyard, assembled, then towed to the site, producing order of magnitude improvements in productivity, quality control, and build time.

https://www.forbes.com/sites/jamesco...t-in-salt/amp/
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Old 1st June 2019, 12:57 PM   #193
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Thanks.

Originally Posted by acbytesla View Post
Check out this recent article in Forbes magazine. I love Thorcon's approach.

One such reactor is ThorCon, a fission reactor with a liquid molten salt fuel containing thorium+uranium. A full-scale 500 MW ThorCon prototype should be able to be built and operating within four years.

"horCon takes a different tack on manufacturing. It would be completely manufactured in 150 to 500 ton blocks in a shipyard, assembled, then towed to the site, producing order of magnitude improvements in productivity, quality control, and build time.

https://www.forbes.com/sites/jamesco...t-in-salt/amp/
If I could have just $1 for every “should” ...
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Old 1st June 2019, 01:07 PM   #194
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Originally Posted by JeanTate View Post
Thanks.



If I could have just $1 for every “should” ...
Sure, but i like the factory approach. There really is no reason that 85 to 90 percent of the construction of these reactors can't be built in a modern shipyard and delivered where it's needed.
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Old 1st June 2019, 01:20 PM   #195
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Originally Posted by acbytesla View Post
Sure, but i like the factory approach. There really is no reason that 85 to 90 percent of the construction of these reactors can't be built in a modern shipyard and delivered where it's needed.
And $2 for every one of these too ...

(not so easy to deliver to a land-locked country, for example ...)
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Old 1st June 2019, 02:21 PM   #196
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Originally Posted by JeanTate View Post
And $2 for every one of these too ...

(not so easy to deliver to a land-locked country, for example ...)
Over 90 percent of today's nuclear power plants are on rivers that are navigable or close to the coast. Also, because of the higher temperatures of Molten Salt, they are not only ideal for electricity generation, but also desalination.
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Old 1st June 2019, 03:49 PM   #197
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Originally Posted by acbytesla View Post
The big problem with nuclear is the expense of building today's reactors. The need to build safe reactors is the crux of the problem. It is what makes them economically uncompetitive. As long as reactors are fighting what is occurs naturally by using solid fuel and pressurized water as the moderator and coolant, I'm afraid nuclear power will never be cost competitive with fossil fuels.
While safety is an issue, it is arguable that the big issue is the permitting process. As it stands, anti-nuclear groups have an explicit policy of making objections serially, rather than all at once.This enormously increases the process time and expense.
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Old 1st June 2019, 04:08 PM   #198
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Candu Reactors (Heavy Water based) are the way to go ... proven technology, very expensive to build ... but this could be streamlined and reduced in cost drastically, by using less union labour, and dispensing with un-necessary government permits, reviews and permission from the public ... JUST built them!
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Old 1st June 2019, 04:25 PM   #199
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Originally Posted by WhatRoughBeast View Post
While safety is an issue, it is arguable that the big issue is the permitting process. As it stands, anti-nuclear groups have an explicit policy of making objections serially, rather than all at once.This enormously increases the process time and expense.
That's just it. The combination of well meaning but short sighted environmentalists and nimbyism, the process for permitting has made it uneconomical. If we can get reactors built and approved in a factory setting,we can reduce cost dramatically.
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Old 1st June 2019, 04:31 PM   #200
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Originally Posted by Ron Swanson View Post
Candu Reactors (Heavy Water based) are the way to go ... proven technology, very expensive to build ... but this could be streamlined and reduced in cost drastically, by using less union labour, and dispensing with un-necessary government permits, reviews and permission from the public ... JUST built them!
The Candu reactors are one if the best built reactors in the world today. But it still uses pressurized water and solid fuel which still has the inherent dangers and is inefficient. I'm. convinced that molten salt reactors are the future of nuclear. Safer, cheaper and more efficient.
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