Japan restarts prototype fast breeder reactor today.

[Statistical]

Japan restarted a costly fast-breeder nuclear reactor Thursday for the first time since it was shut down 14 years ago because of a major accident and cover-up. After getting a final government go-ahead, workers began Thursday removing control rods from the plutonium-fired reactor in the northern fishing town of Tsuruga, said Toshihisa Sakurai, a spokesman for the Japan Atomic Energy Agency.

The experimental reactor Monju, which means wisdom, uses plutonium fuel instead of conventional uranium and produces radioactive substances that can be reused as fuel. It would reach operating level Saturday and continue its test runs before entering full-fledged operation in 2013.

Monju's initial start-up in August 1995 lasted only four months. It was shut down on Dec. 8 of that year when more than a ton of volatile liquid sodium leaked from a secondary cooling system. No one was hurt and no radioactivity escaped, but Monju's operators came under fire for concealing videotape that showed extensive damage to the reactor.

...

The multi-billion-dollar project, which dates back to late 1960s, is part of Japan's ambitious nuclear fuel recycling program. Japan hopes to put the fast-breeder reactor into commercial use around 2050.

http://www.google.com/hostednews/ap/media/ALeqM5hFk8jBNV_8C9PluTsAR_gUbLeVgw?size=l



I diagram of generic sodium cooled FBR. Monju is a loop type (right)



Personally I think pool style if preferable for a variety of reasons.

[NoNothing]

1. What is the transfer medium in the intermediate loop?

[Statistical]

2. It can vary. I believe in Japanese FBR the intermediate loop is pressurized water.

Pressurized to avoid boiling at the temperatures in the loop. Essentially a double walled heat exchanger transfers heat from sodium to water.

Personally I think the ultimate goal is to use a gas as heat transfer mechanism.


http://en.wikipedia.org/wiki/Very_high_temperature_reactor

VHTR uses Helium in primary loop. The proposed design uses the heat to either:
a) produce hydrogen
b) drive steam turbine
c) produce industrial process heat

The ultimate goal would be something like this:


http://en.wikipedia.org/wiki/Gas_cooled_fast_reactor

100% gas cooled and operated. Rather than output steam (to drive a turbine at low thermal efficiency ~30%) the very high temperature gas (1000 deg vs 300 deg for PWR) is run directly through a turbine. This means thermal efficiency is improved to roughly 40% to 45%. In process it works similarly to natural gas turbine except that fission heat is used instead of buring fossil fuels to raise the turbines input gas temperature.

For even more efficiency a combined cycle plant eventually could be built. Using direct turbine and steam boilers the efficiency of a plant could be %60. Getting more and more electrical energy from the same amount of thermal energy.

[NoNothing]

4. That's what I would have guessed

Thanks!

[ensho]

3. kick

nt

[NNadir]

5. I had no idea that Monju was to restart. Some of my nuclear friends are not as fond of plutonium

as I am, but I'm glad to see this reactor running again, although truth be told there are many better approaches to fast reactors than LMFBR.

In order to derive the energy value of the uranium that has already been mined we will certainly want to have fast spectrum reactor experience.

Right now the longest operating experience belongs to the former Soviet reactor in Kazakhstan, the BN-350, the small Phoenix - the Superphoenix remains closed because of ignorance and stupidity - and the Indian fast breeder prototype.

But like I say, this sort of reactor is hardly the best approach to fast spectrum systems - and I'm somewhat ambivalent about it - but as China and India both plan extensive FBR programs, each planning on building 4 - it will be good to accumulate more operable reactor years of experience.

Although I strongly believe in the necessity for using fast spectrum reactors, I also realize that we can make very good use of our depleted uranium reserves - which are an enormous asset - by engaging in a thermal Pu -> Th/U-233 -> U-233/U238 -> Pu cycle. This is much simpler and could be employed readily with a few tweaks in must existing thermal reactor infrastructure.

The IEAE's fast reactor working group consists of 14 countries: Belarus, Brazil, China, France, Germany, India, Italy, Japan, Kazakhstan, Republic of Korea, Russia, Switzerland, United Kingdom, and United States of America. Belgium and Sweden have observer status on the working group.

We may list the members who have or have had official "nuclear phase out" programs: Germany, Italy, Belgium and Sweden. I guess even they don't take their phase outs seriously. No one should. Nuclear phase outs are all environmental disasters designed by the fossil fuel industry as a red herring to keep itself rolling in "green," where "green" refers not to any environmental concern but purely to money, money, money.

There are some other ironies in this group. For instance it would appear that Belarus is not tuned into all the rhetoric of lightweight scientifically illiterate bloggers who think that Chernobyl is the only reactor that ever operated, even though Belarus experienced the most contamination from Chernobyl. They seem to be laboring under the belief that everyone in their country wasn't wiped out by Chernobyl, even if lightweight anti-science bloggers wish to represent that everyone in Belarus, Russia and Ukraine died as a result of Chernobyl.

What I don't necessarily like about the working group is that this is a liquid metal crowd. Like I say, there are far better approaches.