First commercial nuclear power plant in the US - 1957 - Page 1
Forum section: electronics / general

author: rrinker
author_rank: Super Contributor
timestamp: March 21, 2017, 11:08:34 pm
content: Shippingport, PA - other side of the stste from where I live.

author: DenzilPenberthy
author_rank: Frequent Contributor
timestamp: March 22, 2017, 12:03:52 pm
content: Interesting that it appears to be genuinely only for civil use. Our early reactors were all plutonium factories dressed up as civil projects I believe.Also Shippingport is really hard to read in upper-case cyrillic

author: Kevman
author_rank: Regular Contributor
timestamp: March 22, 2017, 12:30:58 pm
content: That's about a 25 minute drive from me. I have driven past it.Most people around here don't realize that it has been decommissioned- they think that the Beaver Valley Nuclear Generating Station is Shippingsport and call it that. Bit of a point of pride in the Pittsburgh area, having the first nuclear power plant in the US.There's a lot of nuclear around here- Three Mile Island isn't all that far (driven past it many times), and a company called NUMEC dumped a ton of... Something... In an area about 15 minutes from my parents. NUMEC also managed to loose something like 500 pounds of highly enriched Uranium ("The Apollo affair").Some contractors were called in to clean it up as a superfund site- but got the hell out of dodge after a while. Then they started patrolling it with military armed with Assault rifles and the Core of Engineers took over. Perhaps they found the uranium?There isn't much land value to that area anymore, but my parents are far enough away it doesn't affect them. The Actual damage is surprisingly localized.

author: rrinker
author_rank: Super Contributor
timestamp: March 22, 2017, 02:17:21 pm
content: Yes, I'm not far from TMI and Peach Bottom. Also driven past Berwick many times. Still envy my ex over that - as an employee of PP&L she got to tour Berwick.I'm about 20 minutes from Limerick. Far enough to not have warning sirens around on poles, I drive by there on a fairly regular basis.

author: Delta
author_rank: Super Contributor
timestamp: March 22, 2017, 03:37:58 pm
content: Fantastic feat of science and engineering.

author: tggzzz
author_rank: Super Contributor
timestamp: March 22, 2017, 03:46:51 pm
content: I'm glad the title was "... in the US ...", since the first full-scale nuclear power plantwasn'tin the US andwasn'tin 1957.It was in the UK in 1956http://www.sellafieldsites.com/2016/10/sixty-years-since-the-day-that-changed-the-nuclear-industry/

author: DenzilPenberthy
author_rank: Frequent Contributor
timestamp: March 27, 2017, 02:27:29 pm
content: It's very misleading to describe Calder Hall as a 'commercial' or civil plant though. It was definitely a plutonium factory that sometimes used to feed power to the grid as a by-product...

author: tggzzz
author_rank: Super Contributor
timestamp: March 27, 2017, 03:06:31 pm
content: Quote from: DenzilPenberthy on March 27, 2017, 02:27:29 pmThat kind of claim has been made for the entire UK nuke plants!

author: Towger
author_rank: Super Contributor
timestamp: March 27, 2017, 04:04:20 pm
content: I watched Pandora the other night on Netflix (https://www.netflix.com/ie/title/80158577) about a ageing Korean nuclear power plant hit by an earthquake. Very much on the anti nuclear footing.... Did not think much of their solution at the end, piles of spent fuel rods sitting on top of each other may not have a good outcome.

author: Syntax_Error
author_rank: Regular Contributor
timestamp: March 27, 2017, 10:51:29 pm
content: I know this thread was not about Fukushima Daiichi but I watched this very informative video the other day. It is very clearly articulated and in my opinion with minimal biases.Beware link hopping on Youtube, as there is currently a TON of Fukushima-apocalypse fear-mongering videos right now.

author: yuzuha
author_rank: Contributor
timestamp: March 27, 2017, 10:57:16 pm
content: Quote from: Towger on March 27, 2017, 04:04:20 pmMolten salt thorium reactors would be cheaper, don't make plutonium and don't require power like Fukashima

author: Red Squirrel
author_rank: Super Contributor
timestamp: March 27, 2017, 11:09:50 pm
content: Quote from: yuzuha on March 27, 2017, 10:57:16 pmI read on thorium reactors at some point and it really sounds like a viable solution. It's really sad there's so much political BS when it comes to nuclear.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 28, 2017, 12:35:22 pm
content: The molten salt reactors have trouble of their own. One of the two experimental reactors (MSRE) form the 1960's is still sitting there and waiting for a solution disposal. It was shut down with the fuel in side. In 1994 they found that the salt was decomposing under the influence of radiation an radioactive fuel in gaseous form was moving through the reactor system. If left unnoticed longer this might even have cause criticality outside the actual reactor core. It was rather close to a nasty release of highly radioactive uranium 233. So it took a rather expensive cleanup to at least remove to uranium fuel in 2008. The rest of the reactor and fuel salt is still waiting for disposal, as there is no destination for this type of waste.Besides of that incident, the chemical separation of fuel and fission products needed to us thorium fuel turned out to be very difficult. Chances are it will be way to expensive. Also corrosion and radiation damages are still a problem. After about 2 years of operation at rather moderate power levels the materials from the MSRE were essentially end of life due to corrosion and radiation damage. Also the idea of passive cooling was more like a design requirement - nothing specific to a molten salt reactor. The molten salt even makes passive cooling more tricky than in conventional reactors. New conventional reactors are also designed to be more or less passive cooled - similar to, but a little better than block 1 in Fukushima.Finally there is a problem surprisingly similar to the fast breeder reactors: if the reactor is made to produce enough fuel by breeding (which is the only way to use thorium as a fuel in a thermal reactor), the reactor design tends to get unstable, with a positive void coefficient, just like the Chernobyl reactor. While the small test reactor was reasonable safe because of favorable stability, large breeding reactors tend to be not.The initial video showed a reactor the separate seed and banket fuel - thus a concept well suited for plutonium production.

author: rstofer
author_rank: Super Contributor
timestamp: March 28, 2017, 03:15:46 pm
content: I guess there is a dose of semantics involved with 'first' since the GE plant at Vallecitos, CA has claim to serial number 1.https://en.wikipedia.org/wiki/Vallecitos_Nuclear_Center

author: Kleinstein
author_rank: Super Contributor
timestamp: March 28, 2017, 03:22:41 pm
content: Estimated from the energy produced, the Vallecitos reactor is much smaller. So not really full scale commercial. Compared to modern reactors the Shippingport reactor is also small.

author: magetoo
author_rank: Frequent Contributor
timestamp: March 29, 2017, 12:21:14 pm
content: Quote from: Kleinstein on March 28, 2017, 12:35:22 pmA gas is much less dense than a liquid. How would you get enough uranium in gaseous form (UF6?) together in one place to achieve criticality, when the system is designed to avoid criticality in fluid form?QuoteYou don't need to separate uranium fuel from the fission products in order to use thorium. It's a separate thing, and a benefit from using a fluid fuel; if you can separate out the fission products you can get more complete fuel burnup and much less and shorter-lived waste. Whether the uranium initially came from breeding thorium or not makes no difference. (I believe there is at least one company working on a design that just leaves this part out entirely, but those might be non-breeding designs, I'm not sure.)Either way it's just chemical engineering, and it doesn't even seem that hard. The existence of plutonium-based weapons is one proof that chemical processes like this can be done even when things are radioactive.QuoteThe "E" in the name stands for "Experiment", it was never designed to be an operating power reactor or to last forever. The advocates for new thorium/molten salt designs have been talking about the need to find the right materials for new designs since the beginning. It's another problem to be solved.QuoteI've heard some criticisms about it not being such a slam dunk as it's often portrayed as, when it comes to the reactivity coefficient changing with temperature. Is that what you're talking about?If it only affects large reactors I guess it's a good thing that everyone is working on small ones.QuoteBy putting a blanket of U238 around it? That should work, but given that the two-fluid designs that are worked on will actively remove U from the blanket in order to use it as fuel, I don't see how any of these proposed commercial designs could be used.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 29, 2017, 04:52:27 pm
content: The problem on the MSRE aftermath was in deed the formation of UF6 gas (at high enough temperature) that deposited somewhere in the gas handling system, partially transformed back to other forms. They found something like 2 kg of fissile ("weapons grade" by IAEA definition) U233 in the char-coal filter for the off gas system. This part was not that far from criticality (e.g. an additional 1 kg missing, or may be just a water ingress) as char coal is an effective moderator. AFAIK the filter part is already outside the containment.Without chemical separation, the liquid fuel reactor would send quite a lot of fissile material to the waste - about twice as much as solid fueled reactor, as there is no separation of fresh and spend fuel.So at least some degree of separation is needed. To use thorium as a fuel and thus reach break even breeding, there is quite a lot of chemical separation needed - way more (e.g. 10-100 times) than with a fast breeding reactor in the U-Pu cycle. The chemical separation does not really help with short lived waste - it just removes it from the reactor core to send it to off site storage. The separation helps in that bread Pu239 or U233 is not send to the waste - so less long term radioactivity.Especially the separation of thorium and fission products is really difficult (in the salt process even more difficult than the recovery of plutonium). It barely works in the non radioactive case to get rare earth elements from monazite sand and causes a lot of waste and emissions. So no way to use those same dirty technology with radioactive material. Due to the large thorium inventory the amount of thorium that would need cleaning is also much larger (e.g. 100 times) than the plutonium in the U-Pu cycle. So with the current state of technology it is more like sending much of the thorium mixed with radioactive rare earth elements to waste. So no even near to the claimed use of 99% of the thorium, more like 0.1 % or less. Recovery of just the uranium seemed to work, at least on experimental scale. There was hope that the reprocessing in the salt process might be easier than of solid fuel - however AFAIK the experiments for fluoride based fuel where not really successful. So not sure that reprocessing is really easier that way.There was quite some effort to improve on the materials used in the MSRE. However these did not fully solve to problems. The lifetime and maximum temperatures are still expected to be rather limited. There might be more advances in that area, as the first wall for fusion reactors might have comparable requirement . Still a lot of fundamental research is needed and special materials tend to increase the costs.The reactivity coefficients and related void coefficient is the problem I was referring to. There where quite a few tries to design a single fluid, thermal breeding core with favorable coefficients and they essentially all failed or at least required chemical reprocessing at non feasible rates. However there is a chance that a core blanket design, with a separate breeding blanket could by made to have acceptable stability. However using two types of fuel dramatically increases the number of possibly accident scenarios and it is even more demanding on the materials used. Another option investigated is a fast neutron design. Here safety seems to be better and less chemical processing is needed, but radiation damage to the materials is a problem. Still the fast molten salt reactor is likely the better option.Single fluid small reactors that do not have the reactivity problem are not even close to reach break even breading - so they are not an option for the thorium cycle. On the other side the two fluid versions seems to only work out small scale.The molten salt reactor idea is not limited to thorium fuel. It can also work on uranium / plutonium fuel. The MSRE initially ran on U235/U238 and in this time produced a small amount of weapons grade plutonium. So with suitable chemical processing this type of reactor could even be an effective way to produce high grade plutonium. This might be an additional reason why the research was stopped.According to the video the shipping-port reactor used separate seed and blanked. So this reactor could also have been used to produce at least some weapons plutonium (from those elements that get relatively little radiation) when removed.