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PostPosted: Feb 10, 2012 11:52 am 
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Location: South Carolina
Here's the link to the NRC'c news release on the AP1000 COL approval for the Voglte 3-4 site .
http://www.nrc.gov/reading-rm/doc-colle ... 12-013.pdf

I work at V.C.Summer station, and we are expecting similar news on our COL sometime within the next two months. Our job site look very similar too the Voglte site except that our construction progress look's about two months behind Voglte.

Maybe the 34 year curse has been lifted off the US nuclear industry. Time will tell.

Steve Irwin


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PostPosted: Mar 31, 2012 2:44 pm 
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Location: Columbia, SC
COL approved for VCS Units 2&3 on Friday. Should have actual COL paper in 10 days or less.

Off to the races.


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PostPosted: Mar 31, 2012 7:08 pm 
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I see that Chairman Jaczko was helpful in this decision.......


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PostPosted: Apr 01, 2012 6:45 am 
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arcs_n_sparks wrote:
I see that Chairman Jaczko was helpful in this decision.......


It's good to know that he can't sabotage everything. The other commissioners don't suffer his innuendo and double agenda. Good, good.


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PostPosted: Apr 02, 2012 3:20 am 
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That's good news. 6 new U.S. reactors are coming online this decade. The Vogtle and Summer plants as well as the TVA's Bellefonte 1 and Watts Bar 2 plants. It's typical that all these new plants are in the southeastern part of the USA. Why is nuclear energy not chosen in the rest of the country ?


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PostPosted: Apr 02, 2012 8:26 am 
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camiel wrote:
That's good news. 6 new U.S. reactors are coming online this decade. The Vogtle and Summer plants as well as the TVA's Bellefonte 1 and Watts Bar 2 plants. It's typical that all these new plants are in the southeastern part of the USA. Why is nuclear energy not chosen in the rest of the country ?


There's generally more public support there than in the southwest and northeast. Also I think coal prices are an important factor. Where coal is cheap (close to the cheaper, lower quality coal deposits) nuclear can't compete economically. But its more than decent economically where coal is the most expensive.


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PostPosted: Apr 23, 2012 6:09 am 
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The AP1000 pump has passed qualification testing in the USA.

http://www.world-nuclear-news.org/NN-AP ... 04124.html

(I'm not sure why the design has been certified without a qualified pump. Must be for time/schedule reasons).

This is an important development. It is the biggest canned motor pump in the world. A canned motor pump is techically more attractive than traditional pumps for a LFTR (no seal leaks). Succesful development means it will be easier to use these for a LFTR. The AP1000 needs 4 of these big pumps for the primary loop. A 1 GWe LFTR would only need 1 such a pump for the primary loop (or equivalent capacity smaller pumps). IIUC the dissimilar ceramic bearings and sliders are already used in other industries that pump corrosive and/or high temperature fluids.

Notice the specs: 91 tonnes, 6.9 meters tall, 1.5 meters wide. Big pumps!


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PostPosted: Apr 23, 2012 7:10 pm 
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Location: Columbia, SC
Cyril R wrote:
The AP1000 pump has passed qualification testing in the USA.

http://www.world-nuclear-news.org/NN-AP ... 04124.html

(I'm not sure why the design has been certified without a qualified pump. Must be for time/schedule reasons).

This is an important development. It is the biggest canned motor pump in the world. A canned motor pump is techically more attractive than traditional pumps for a LFTR (no seal leaks). Succesful development means it will be easier to use these for a LFTR. The AP1000 needs 4 of these big pumps for the primary loop. A 1 GWe LFTR would only need 1 such a pump for the primary loop (or equivalent capacity smaller pumps). IIUC the dissimilar ceramic bearings and sliders are already used in other industries that pump corrosive and/or high temperature fluids.

Notice the specs: 91 tonnes, 6.9 meters tall, 1.5 meters wide. Big pumps!


Maybe, but I think it would be better to use a long shaft and keep the motor out of the hot cell. Those rad levels are going to be extreme, not to mention the molten salt environment on the bearings. Remember a canned RCP was developed because of the high primary system pressure (2250psia), and the desire to eliminate seal cartridges for a variety of reasons. No need for that level of difficulty on a LFTR at atmospheric pressure. Your seal leakage problem goes away with the lower pressure.


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PostPosted: Apr 24, 2012 9:41 am 
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USPWR_SRO wrote:
Cyril R wrote:
The AP1000 pump has passed qualification testing in the USA.

http://www.world-nuclear-news.org/NN-AP ... 04124.html

(I'm not sure why the design has been certified without a qualified pump. Must be for time/schedule reasons).

This is an important development. It is the biggest canned motor pump in the world. A canned motor pump is techically more attractive than traditional pumps for a LFTR (no seal leaks). Succesful development means it will be easier to use these for a LFTR. The AP1000 needs 4 of these big pumps for the primary loop. A 1 GWe LFTR would only need 1 such a pump for the primary loop (or equivalent capacity smaller pumps). IIUC the dissimilar ceramic bearings and sliders are already used in other industries that pump corrosive and/or high temperature fluids.

Notice the specs: 91 tonnes, 6.9 meters tall, 1.5 meters wide. Big pumps!


Maybe, but I think it would be better to use a long shaft and keep the motor out of the hot cell. Those rad levels are going to be extreme, not to mention the molten salt environment on the bearings. Remember a canned RCP was developed because of the high primary system pressure (2250psia), and the desire to eliminate seal cartridges for a variety of reasons. No need for that level of difficulty on a LFTR at atmospheric pressure. Your seal leakage problem goes away with the lower pressure.


Good point, I hadn't considered that. I wonder though - the AP1000 primary coolant pumps have to deal with powerful gamma radiation as well (though there are no neutrons of course). So I figured they at least solved the rad shielding problem for the motor.

But it would be great if we can just use the ORNL long shaft pump design to get started. In the buffer salt concept, this allows to motor to be above the buffer salt liquid level. ORNL thought that pumps would be one of the biggest RD&D requirements for upscaling to MSBR power levels.


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PostPosted: Apr 24, 2012 3:15 pm 
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Cyril R wrote:
...Good point, I hadn't considered that. I wonder though - the AP1000 primary coolant pumps have to deal with powerful gamma radiation as well (though there are no neutrons of course). So I figured they at least solved the rad shielding problem for the motor.

But it would be great if we can just use the ORNL long shaft pump design to get started. In the buffer salt concept, this allows to motor to be above the buffer salt liquid level. ORNL thought that pumps would be one of the biggest RD&D requirements for upscaling to MSBR power levels.


The rad levels are orders of magnitude higher for the MSBR hot cell compared to what a AP1000 RCP motor will see. Yes, it will see a lot of nasty N-16 gammas and a measurable neutron field, but not anything like the gamma and neutron field in that hot cell. Think of it like this, the MSBR hot cell is comparable to being inside the core of a LWR.


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PostPosted: Apr 24, 2012 4:42 pm 
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USPWR_SRO wrote:
Cyril R wrote:
...Good point, I hadn't considered that. I wonder though - the AP1000 primary coolant pumps have to deal with powerful gamma radiation as well (though there are no neutrons of course). So I figured they at least solved the rad shielding problem for the motor.

But it would be great if we can just use the ORNL long shaft pump design to get started. In the buffer salt concept, this allows to motor to be above the buffer salt liquid level. ORNL thought that pumps would be one of the biggest RD&D requirements for upscaling to MSBR power levels.


The rad levels are orders of magnitude higher for the MSBR hot cell compared to what a AP1000 RCP motor will see. Yes, it will see a lot of nasty N-16 gammas and a measurable neutron field, but not anything like the gamma and neutron field in that hot cell. Think of it like this, the MSBR hot cell is comparable to being inside the core of a LWR.


I'm not sure about this. The pump internals would see a delayed neutron flux from contact with the primary salt in any pump design. I see no problems there. The problems if any would be in the motor system. But N-16 gammas, during fullpower operation, are a big rad field for the AP1000 loop. Now the AP1000 pump is almost 7 meters tall. So you do have a lot of distance (and metal) from stator to impellor. What exactly stops us from using pumps in high rad field anyway, if you have ceramic insulation on the copper wiring for the stator? There's not any reason to have electronic circuitry near the pump itself is there? (maybe stupid questions, I'm not really a pump guy).

For a buffer salt pool concept, gamma rad field drops rapidly with buffer salt cover, and neutrons are not allowed to pass to the buffer salt in significant quantities by neutronic protections.


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PostPosted: Apr 24, 2012 4:48 pm 
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There won't be much N-16 gamma in the hot cell, but there surely will be a lot of high energy gammas from fission products. And I would worry about winding insulation more than anything else.


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PostPosted: Jun 10, 2012 8:17 am 
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Rod Adams has an article that provides evidence for my claims that the NRC should be abolished if nuclear power is to be more meaningful in the US.

http://ansnuclearcafe.org/2012/06/06/st ... hard-work/

The rebar case is a good example of why the NRC retards innovation, creative thinking, and common sense safety analysis.

Clearly the nuclear renaissance isn't going anywhere in the US. It's a big deja-vu. The NRC hasn't learned, despite their bragging about COLs and streamlined licensing, they're about as innovative and flexible as a brick. It is exactly the same situation as the 1980's.


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