Clear The Air Energy Blog Rotating Header Image

Thorium Salt

Introduction to the LFTR

The Liquid Fluoride Thorium Reactor

http://www.thoriumsingapore.com/content/index.php?option=com_content&view=article&id=50&Itemid=37

Nuclear Power Is Extremely Safe — That’s the Truth About What We Learned From Japan

http://thorium.klimabedrag.dk/

In the midst of a still struggling and fragile global economy, Germany has announced that it will shut down seven nuclear plants by the end of the year – which means that Germans will be left to run their factories, heat their homes, and power their economy with 10% less electrical generating capacity. Nine more plants will be shut down over the next decade and tens of billions of dollars in investment will be lost.

The grounds for this move, and similar proposals in Switzerland, Italy, and other countries, is safety. As the Swiss energy minister put it, “Fukushima showed that the risk of nuclear power is too high.”

In fact, Fukushima showed just the opposite. How’s that? Well for starters, ask yourself what the death toll was at Fukushima. 100? 200? 10? Not true. Try zero.

To think rationally about nuclear safety, you must identify the whole context. As the late, great energy thinker Petr Beckmann argued three decades ago in his contrarian classic “The Health Hazards of NOT Going Nuclear,” every means of generating power has dangers and risks, but nuclear power “is far safer than any other form of large-scale energy conversion yet invented.”

To date, there have been devised only five practical means of producing large-scale, affordable, reliable energy: coal, natural gas, oil, hydroelectric, and nuclear. (Although widely hyped and frequently subsidized, solar and wind power – which generate energy from highly diffuse and intermittent sources – have failed for forty years to deliver.) Whether you’re concerned about a dangerous accident or harmful emissions, a nuclear power plant is the safest way to generate power.

The key to nuclear power’s safety, Beckmann explains, is that it uses a radioactive energy source – such as uranium. In addition to having the advantage of storing millions of times more energy per unit of volume than coal, gas, or water, the radioactive material used in power plants literally cannot explode. Ridiculing the scare tactics that a nuclear power plant poses the same dangers as a nuclear bomb, Beckmann observes: “An explosive nuclear chain reaction is no more feasible in the type of uranium used as power plant fuel than it is in chewing gum or pickled cucumbers.”

The one danger of running a nuclear plant is a large release of radiation. This is extremely unlikely, because nuclear plants contain numerous shielding and containment mechanisms (universal in the civilized world but callously foregone by the Soviets in their Chernobyl plant).

But in the most adverse circumstances, as Fukushima illustrated, the cooling system designed to moderate the uranium’s heat can fail, the backups can fail, the radioactive material can overheat to the point that the plant cannot handle the pressure, and a radiation release is necessary.

Yet, even then, it is extremely unlikely that the radiation levels will be high enough to cause radiation sickness or cancer – and radiation in modest quantities is a normal, perfectly healthy feature of life (your blood is radioactive, as is the sun). And even the worst nuclear accident gives neighbors a luxury that broken dams and exploding refineries do not: time.
….

While many, many things went wrong at Fukushima, as might be expected in an unprecedented natural disaster, what is more remarkable is that thanks to the fundamental integrity of the nuclear vessel and the containment building, none of the power plant’s neighbors have died, nor have any apparently been exposed to harmful levels of radiation. (The Japanese government has announced that eight of 2,400 workers have been exposed to higher-than-allowed amounts of radiation, but these amounts are often hundreds of times less than is necessary to do actual damage.)

Now imagine if a 9.0 earthquake and 40 foot tsunami had hit a hydroelectric dam; thousands of people could have died in the ensuing flood.
….

The Fukushima nuclear plants, with their incredible resilience, almost certainly saved many, many lives.

Nuclear power also saves lives that would otherwise be lost to pollution. A nuclear power plant has effectively zero harmful emissions. (It generates a small amount of waste, which France, among other countries, has demonstrated can be both re-used economically and stored safely.) By contrast, fossil fuel plants generate various forms of particulate matter that strongly correlate with higher cancer rates. We should not “knock coal,” Beckmann stressed, as fossil fuel plants are vital for human survival for decades to come, but we should recognize that new nuclear power plants are far safer than the status quo.
….

As a consequence of the anti-nuclear hysteria in Beckmann’s time, the U.S. government made it either impossible or economically prohibitive to build new plants, in the name of “safety.” Fukushima has affirmed that nuclear is the safest form of power in existence. Any government that fails to recognize this is endangering its citizens’ health.

By Alex Epstein Published July 23, 2011, FoxNews.com

Alex Epstein is a fellow at the Ayn Rand Center for Individual Rights, specializing in energy issues. The Ayn Rand Center is a division of the Ayn Rand Institute.

Read the full article at FoxNews

Unclear On Nuclear? Try Thorium – Nuclear Energy Without The Side Effects

HomeInventor  Inventor Spot   23 March 2011

If the current events in Japan have demonstrated one thing, it’s that nuclear energy in its current form is not safe. Put simply, if the Japanese can’t do it right with their impeccable approach to workmanship, then heaven help the rest of us.

But nuclear energy produces about 13,000 times the amount of energy per pound of fuel than coal, and considerably less waste. The only problem with the waste, of course, is that uranium and plutonium produce immeasurably more dangerous waste than coal, or oil, or natural gas, or any other energy source currently in widespread use: not only does it need to be stored safely for thousands of years (like that’s going to happen), but if it gets in the wrong hands, well, use your imagination.

With so many unknowns surrounding nuclear power – the impossibility of 100% safe operation; the unlikeliness of ensuring safe storage of nuclear waste across millennia; the probability of some of that waste ending up in the hands of terrorists or rogue states – you could justifiably be wondering why there are nearly 450 nuclear power stations operating around the world, with a further 65 under construction.

You could especially be wondering why, if you knew that a way to process a much safer form of nuclear energy has been available for nearly the last half a century. And then if you discovered that the source of this energy was four times more abundant than uranium (which contains all the plutonium), you could well be vigorously shaking and slapping your head simultaneously.

Don’t do it to yourself! Even if it is true that thorium possesses all these properties.

The primary advantage of thorium is probably safety. As reported recently in The Telegraph, thorium expert Kirk Sorensen claims that, “If it begins to overheat, a little plug melts and the salts drain into a pan. There is no need for computers, or the sort of electrical pumps that were crippled by the tsunami. The reactor saves itself. They operate at atmospheric pressure so you don’t have the sort of hydrogen explosions we’ve seen in Japan. One of these reactors would have come through the tsunami just fine. There would have been no radiation release.” This is largely because thorium is not fissile: it cannot sustain a nuclear chain reaction without a catalyst.

But that’s not all. Because thorium is lighter than uranium (which is lighter than plutonium), it doesn’t produce as many heavy, radioactive byproducts. It produces considerably less waste than its heavier cousins, and that is waste that only needs to be managed for 500 years – still a long time, but nowhere near the 10,000 years that some existing nuclear waste requires. That’s if you want to store it. Alternatively, you could add a bit of plutonium to the mix, and you’d burn it all up as part of the energy creation process. That’s right: handled properly, a thorium reactor produces no radioactive waste.

Oh, and thorium comes out of the ground as 100% thorium. It doesn’t need to be enriched, like uranium, which contains less than 1% fissionable material. So, while there is around four times as much thorium in the ground as uranium, there is closer to 6,000 times more usable thorium than usable uranium.

In the USA, which possesses the world’s largest thorium reserves, an experimental thorium reactor was built at the Oak Ridge National Laboratory in Tennessee back in the ’60s, operating for around five years before its funding was cut. Today, there is an operating thorium reactor in India, and plans for them in China, Russia and Norway.

Liquid Fluoride Thorium Reactor

A quite different concept is the Liquid Fluoride Thorium Reactor (LFTR), utilizing U-233 which has been bred in a liquid thorium salt blanket.

The core consists of fissile U-233 tetrafluoride in molten fluoride salts of lithium and beryllium at some 700°C and at low pressure within a graphite structure that serves as a moderator and neutron reflector. Fission products dissolve in the salt and are removed progressively – xenon bubbles out, others are captured chemically. Actinides are less-readily formed than in fuel with atomic mass >235, and those that do form stay in the fuel until they are transmuted and eventually fissioned.

The blanket contains a mixture of thorium tetrafluoride in a fluoride salt containing lithium and beryllium, made molten by the heat of the core. Newly-formed U-233 forms soluble uranium tetrafluoride (UF4), which is converted to gaseous uranium hexafluoride (UF6) by bubbling fluorine gas through the blanket solution (which does not chemically affect the less-reactive thorium tetrafluoride). Uranium hexafluoride comes out of solution, is captured, then is reduced back to soluble UF4 by hydrogen gas in a reduction column, and finally is directed to the core to serve as fissile fuel.

The LFTR is not a fast reactor, but with some moderation by the graphite is epithermal (intermediate neutron speed). Safety is achieved with a freeze plug which if power is cut allows the fuel to drain into subcritical geometry in a catch basin. There is also a negative temperature coefficient of reactivity due to expansion of the fuel.

The China Academy of Sciences in January 2011 launched an R&D program on LFTR, known there as the thorium-breeding molten-salt reactor (Th-MSR or TMSR), and claimed to have the world’s largest national effort on it, hoping to obtain full intellectual property rights on the technology.