Tuesday, February 21, 2012

Thorium Reactors and Fast Breeder Reactors in the News

The Washington Post is reporting on the recent push for thorium nuclear reactors in the US.
... a small group of scientists, entrepreneurs and advocates see the post-Fukushima era as the perfect opportunity to get the United States to consider a proposal they have made with no success for years. What about trying a new fuel, they say, and maybe a new kind of reactor?

The proposed fuel is thorium, an abundant silver-gray element named for the Norse god of thunder. It is less radioactive than the uranium that has always powered U.S. plants, and advocates say that not only does it produce less waste, it also is more difficult to turn into nuclear weapons.

They’re pushing the idea of adapting plants to use thorium as a fuel or replacing them with a completely new kind of reactor called a liquid-fluoride thorium reactor, or LFTR (pronounced “lifter”). The LFTR would use a mixture of molten chemical salts to cool the reactor and to transfer energy from the fission reaction to a turbine.

Proponents say such a system would be more efficient and safer than existing plants, which use pressurized water to cool uranium fuel rods and boiling water or steam to transfer the energy they create.

“A molten-salt reactor is not a pressurized reactor,” said John Kutsch, director of the Thorium Energy Alliance, a trade group based in Harvard, Ill. “It doesn’t use water for cooling, so you don’t have the possibility of a hydrogen explosion, as you did in Fukushima.”

Kutsch and others say that a thorium-fueled reactor burns hotter than uranium reactors, consuming more of the fuel. “Ninety-nine percent of the thorium is burned up,” he said. “Instead of 10,000 pounds of waste, you would have 300 pounds of waste.” _WaPo
Thorium is approximately three times as abundant as uranium in the earth’s crust, reflecting the fact that thorium has a longer half-life. In addition, thorium generally is present in higher concentrations (2-10%) by weight than uranium (0.1-1%) in their respective ores, making thorium retrieval much less expensive and less environmentally damaging per unit of energy extracted. Countries with significant thorium mineral deposits include: Australia, India, Brazil, USA, Canada, China, Russia, Norway, Turkey, Venezuela, Sri Lanka, Nigeria, South Africa, and Malaysia.

Naturally occurring thorium has one isotope- thorium-232. In the DBI reactor, the initial start up fuel mix is a combination of thorium and uranium-235. The uranium acts as the “seed” source of neutrons needed to achieve criticality for the first reactor. This combination of fuels decreases the time and capital required to start the thorium fuel breeding cycle. As the DBI reactor design begins producing electricity, Uranium-233, bred from the Thorium-232, increased core reactivity and power output. Over time, the original uranium-235 is burned up and subsequently the reactor is fuelled only with Thorium-232. Over the life of the DBI reactor design (approx. 60 years), about 3% of the original load mass (thorium only) will be added every 18 months. Depending upon operational choices available with the DBI designs, no or very little additional uranium will be needed. _DBI
As noted here recently, famed futurist Gerald Celente is proposing that Iran and other unstable third world dictatorships consider developing thorium cycle reactors rather than uranium cycle, should they insist upon developing a nuclear infrastructure.
The thorium cycle is far more efficient and simpler than the uranium cycle. So besides the fact that significantly more thorium reserves are present than uranium, it is possible to extract far more of the potential energy from the thorium -- with much less effort -- than from uranium.
Thorium is well distributed globally, providing an ample supply for industrial and emerging nations well into the future.

More information on the future of thorium energy:  Flibe

Besides thorium, other alternative approaches to nuclear reactors being developed include the fast breeder reactor. Brian Wang looks at fast breeder reactor development in India and other countries. More on the Indian FBR development:
India plans to commission the first-of-its-kind Prototype Fast Breeder Reactor (PFBR) early in 2013, kickstarting the second stage of its nuclear programme. The 500 MWe reactor, being developed by the Indira Gandhi Centre for Atomic Research (IGCAR) at Kalpakkam in Tamil Nadu, uses a unique mix of uranium and plutonium which significantly enhances the capability to generate electricity per tonne of fuel utilised.

The indigenously-developed PFBR is at an advanced stage of construction under the aegis of state-owned Bhartiya Nabhikiya Vidyut Nigam (BHAVINI).

"The construction will be completed by September and fuel will be lowered by December. We expect commissioning by early 2013," IGCAR Director S C Chetal said here. _HindustanTimes
Future high-tech nuclear infrastructures in advanced countries will likely include LFTRs, advanced PWRs, integral fast reactors, gas cooled high temperature reactors, and a variety of small modular reactors meant to produce both electrical power and industrial process heat.

As noted here many times, nuclear power is well suited to assist in the production of a wide array of synthetic liquid hydrocarbon fuels as well as industrial chemicals, lubricants, and other high value materials such as polymers. In this manner, nuclear power will act to generate plentiful substitutes for crude oil, at a time when political turmoil and "the coming anarchy" is likely to lead to frequent artificially caused short supply of crude.



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