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Thorium Molten Salt Nuclear reactor (MSR) No Better Than Uranium Process

The safety issue is also not resolved, as stated above: pressurized water leaking from the steam generator into the hot, radioactive molten salt will explosively turn to steam and cause incredible damage.  The chances are great that the radioactive molten salt would be discharged out of the reactor system and create more than havoc.  Finally, controlling the reaction and power output, finding materials that last safely for 3 or 4 decades, and consuming vast quantities of cooling water are all serious problems.  

The greatest problem, though, is likely the scale-up by a factor of 500 to 1, from the tiny project at ORNL to a full-scale commercial plant with 3500 MWth output.   Perhaps these technical problems can be overcome, but why would anyone bother to try, knowing in advance that the MSR plant will be uneconomic due to huge construction costs and operating costs, plus will explode and rain radioactive molten salt when (not if) the steam generator tubes leak.

The Truth About Nuclear Power – Part 28, Sowells Law Blog , 14 July 2014 Thorium MSR No Better Than Uranium Process, 

Preface   This article, number 28 in the series, discusses nuclear power via a thorium molten-salt reactor (MSR) process.   (Note, this is also sometimes referred to as LFTR, for Liquid Fluoride Thorium Reactor)   The thorium MSR is frequently trotted out by nuclear power advocates, whenever the numerous drawbacks to uranium fission reactors are mentioned.   To this point in the TANP series, uranium fission, via PWR or BWR, has been the focus.  Some critics of TANP have already stated that thorium solves all of those problems and therefore should be vigorously pursued.  Some of the critics have stated that Sowell obviously has never heard of thorium reactors.   Quite the contrary, I am familiar with the process and have serious reservations about the numerous problems with thorium MSR.

It is interesting, though, that nuclear advocates must bring up the MSR process.  If the uranium fission process was any good at all, there would be no need for research and development of any other type of process, such as MSR and fusion. Continue reading

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October 5, 2018 Posted by | 2 WORLD, Reference, technology, thorium | Leave a comment

Thorium nuclear reactors and their ability to produce nuclear weapons material

The half-lives of the protactinium isotopes work in the favor of potential proliferators. Because protactinium 232 decays faster than protactinium 233, the isotopic purity of protactinium 233 increases as time passes. If it is separated from its uranium decay products a second time, this protactinium will decay to equally pure uranium 233 over the next few months. With careful attention to the relevant radiochemistry, separation of protactinium from the uranium in spent thorium fuel has the potential to generate uranium 233 with very low concentrations of uranium 232—a product suitable for making nuclear weapons. 

Thorium power has a protactinium problem https://thebulletin.org/2018/08/thorium-power-has-a-protactinium-problem/ By Eva C. Uribe, August 6, 2018  In 1980, the International Atomic Energy Agency (IAEA) observed that protactinium, a chemical element generated in thorium reactors, could be separated and allowed to decay to isotopically pure uranium 233—suitable material for making nuclear weapons. The IAEA report, titled “Advanced Fuel Cycle and Reactor Concepts,” concluded that the proliferation resistance of thorium fuel cycles “would be equivalent to” the uranium/plutonium fuel cycles of conventional civilian nuclear reactors, assuming both included spent fuel reprocessing to isolate fissile material.

Decades later, the story changed. “Th[orium]-based fuels and fuel cycles have intrinsic proliferation resistance,” according to the IAEA in 2005. Mainstream media have repeated this view ever since, often without caveat. Several scholars have recognized the inherent proliferation risk of protactinium separations in the thorium fuel cycle, but the perception that thorium reactors cannot be used to make weapons persists. While technology has advanced, the fundamental radiochemistry that governs nuclear fuel reprocessing remains unchanged. Thus, this shift in perspective is puzzling and reflects a failure to recognize the importance of protactinium radiochemistry in thorium fuel cycles. 

Protactinium turns 100. The importance of protactinium chemistry for obtaining highly attractive fissile material from thorium has been recognized since the 1940s. However, the story really begins 100 years ago during the earliest research on natural radioactivity. In 1918, Austrian-Swedish physicist Lise Meitner and German chemist Otto Hahn were on a quest to discover the long-lived isotope of “eka-tantalum” predicted to lie between thorium and uranium in the periodic table. The isotope they sought would decay to actinium, which was always found with uranium but was known to be the parent of an unknown natural radioactive decay chain distinct from that of uranium 238, the most common isotope of uranium found in nature.

Meitner and Hahn discovered that treating pitchblende with nitric acid yielded an insoluble fraction of silica that associated with tantalum and eka-tantalum. After many years, they purified enough eka-tantalum for identification and measured its properties. As discoverers of eka-tantalum’s longest-lived isotope, Meitner and Hahn named this new element protactinium. They had isolated protactinium 231, a member of the uranium 235 decay chain. In 1938, they discovered that protactinium 233 could be produced by neutron irradiation of thorium 232, the most abundant isotope in naturally occurring thorium.

For the next several decades, protactinium was shrouded in “mystery and witchcraft” due to its scarcity in nature and its perplexing chemical properties. We now know that protactinium’s peculiar chemistry is due to its position in the periodic table, which lends the element vastly different chemical properties than its neighbors. Protactinium behaves so differently from thorium and uranium that, under many conditions, their separation is inevitable.
Scientists did not investigate the macroscopic chemistry of protactinium until the Manhattan Project. In 1942, Glenn T. Seaborg, John W. Gofman, and R. W. Stoughton discovered uranium 233 and observed its propensity to fission. Compared with naturally occurring uranium 235, uranium 233 has a lower critical mass, which means that less material can be used to build a weapon. And compared with weapons-grade plutonium 239, uranium 233 has a much lower spontaneous fission rate, enabling simpler weapons that are more easily constructed. A 1951 report by the Manhattan Project Technical Section describes extensive efforts devoted to the production of uranium 233 via neutron irradiation of thorium 232. Because the initial thorium feed material was often contaminated with natural uranium 238, the scientists obtained pure uranium 233 by using a variety of methods for separating the intermediate protactinium 233.

By this time, advances in technology and projections of uranium shortages stimulated interest in developing a breeder reactor, which produces more fissile material than it consumes. In the late 1960s, a team at Oak Ridge National Laboratory designed a Molten Salt Breeder Reactor fueled by thorium and uranium dissolved in fluoride salts, but it could only breed uranium 233 by continuously removing impurities—including protactinium 233—from the reactor core. To improve breeding ratios, the researchers investigated methodsfor removing protactinium from the molten fluoride salts.

In 1977, President Jimmy Carter banned commercial reprocessing of spent nuclear fuel, citing concerns with the proliferation of technology that could be used to make nuclear weapons. And with the high startup costs of developing new reactors, there would be no place for the Molten Salt Breeder Reactor in the energy market. With the end of research on thorium reactors came the end of ambitious research on protactinium separations. Over time, the role of protactinium in obtaining weaponizable uranium 233 from thorium was largely forgotten or dismissed by the thorium community.

Thorium reactors born again. Fast forward to 2018. Several nations have explored thorium power for their nuclear energy portfolios. Foremost among these is India. Plagued by perennial uranium shortages, but possessing abundant thorium resources, India is highly motivated to develop thorium reactors that can breed uranium 233. India now operates the only reactor fueled by uranium 233, the Kalpakkam Mini reactor (better known as KAMINI).

Thorium reactors have other potential advantages. They could produce fewer long-lived radioactive isotopes than conventional nuclear reactors, simplifying the disposal of nuclear waste. Molten salt reactors offer potential improvements in reactor safety. Additionally, there is the persistent perception that thorium reactors are intrinsically proliferation-resistant.

The uranium 233 produced in thorium reactors is contaminated with uranium 232, which is produced through several different neutron absorption pathways. Uranium 232 has a half-life of 68.9 years, and its daughter radionuclides emit intense, highly penetrating gamma rays that make the material difficult to handle. A person standing 0.5 meters from 5 kilograms of uranium 233 containing 500 parts per million of uranium 232, one year after it has been separated from the daughters of uranium 232, would receive a dose that exceeds the annual regulatory limits for radiological workers in less than an hour. Therefore, uranium 233 generated in thorium reactors is “self-protected,” as long as uranium 232 levels are high enough. However, the extent to which uranium 232 provides adequate protection against diversion of uranium 233 is debatable. Uranium 232 does not compromise the favorable fissile material properties of uranium 233, which is categorized as “highly attractive” even in the presence of high levels of uranium 232. Uranium 233 becomes even more attractive if uranium 232 can be decreased or eliminated altogether. This is where the chemistry of protactinium becomes important.

Protactinium in the thorium fuel cycle. There are three isotopes of protactinium produced when thorium 232 is irradiated. Protactinium 231, 232, and 233 are produced either through thermal or fast neutron absorption reactions with various thorium, protactinium, and uranium isotopes. Protactinium 231, 232, and 233 are intermediates in the reactions that eventually form uranium 232 and uranium 233. Protactinium 232 decays to uranium 232 with a half-life of 1.3 days. Protactinium 233 decays to uranium 233 with a half-life of 27 days. Protactinium 231 is a special case: It does not directly decay to uranium, but in the presence of neutrons it can absorb a neutron and become protactinium 232.

Neutron absorption reactions only occur in the presence of a neutron flux, inside or immediately surrounding the reactor core. Radioactive decay occurs whether or not neutrons are present. For irradiated thorium, the real concern lies in separating protactinium from uranium, which may already have significant levels of uranium 232. Production of protactinium 232 ceases as soon as protactinium is removed from the neutron flux, but protactinium 232 and 233 continue to decay to uranium 232 and 233, respectively.

The half-lives of the protactinium isotopes work in the favor of potential proliferators. Because protactinium 232 decays faster than protactinium 233, the isotopic purity of protactinium 233 increases as time passes. If it is separated from its uranium decay products a second time, this protactinium will decay to equally pure uranium 233 over the next few months. With careful attention to the relevant radiochemistry, separation of protactinium from the uranium in spent thorium fuel has the potential to generate uranium 233 with very low concentrations of uranium 232—a product suitable for making nuclear weapons.
Scenarios for proliferation. Although thorium is commonly associated with molten salt reactors, it can be used in any reactor. Several types of fuel cycles enable feasible, rapid reprocessing to extract protactinium. One is aqueous reprocessing of thorium oxide “blankets” irradiated outside the core of a heavy water reactor. Many heavy water reactors include on-power fueling, which means that irradiated thorium can be removed quickly and often, without shutting the reactor down. As very little fission would occur in the blanket material, its radioactivity would be lower than that of spent fuel from the core, and it could be reprocessed immediately.

Myriad possibilities exist for the aqueous separation of protactinium from thorium and uranium oxides, including the commonly proposed thorium uranium extraction (THOREX) process. Alternatively, once dissolved in acid, protactinium can simply be adsorbed onto glass or silica beads, exploiting the same chemical mechanism used by Meitner and Hahn to isolate protactinium from natural uranium a century ago.

Another scenario is continuous reprocessing of molten salt fuel to remove protactinium and uranium from thorium. Researchers at Oak Ridge explored the feasibility of online protactinium removal in the Molten Salt Breeder Reactor program. Uranium can then be separated from the protactinium in a second step.

Sensible safeguards. Protactinium separations provide a pathway for obtaining highly attractive weapons-grade uranium 233 from thorium fuel cycles. The difficulties of safeguarding commercial spent fuel reprocessing are significant for any type of fuel cycle, and thorium is no exception. Reprocessing creates unique safeguard challenges, particularly in India, which is not a member of the Nuclear Non-Proliferation Treaty.

There is little to be gained by calling thorium fuel cycles intrinsically proliferation-resistant. The best way to realize nuclear power from thorium fuel cycles is to acknowledge their unique proliferation vulnerabilities, and to adequately safeguard them against theft and misuse.

August 10, 2018 Posted by | 2 WORLD, Reference, thorium, weapons and war | Leave a comment

Thorium nuclear power – not so great, really

Today, advocates of thorium typically point to a variety of advantages over uranium. These include fail-safe reactor operation, because most thorium reactor designs are incapable of an explosion or meltdown, as was seen at Chernobyl or Fukushima. Another is resistance to weapons proliferation, because thorium reactors create byproducts that make the fuel unsuitable for use in nuclear weapons.Other advantages include greater abundance of natural reserves of thorium, less radioactive waste and higher utilisation of fuel in thorium reactors. Thorium is often cast as “good nuclear”, while uranium gets to carry the can as “bad nuclear”.

Not so different

While compelling at first glance, the details reveal a somewhat more murky picture. The molten salt architecture which gives certain thorium reactors high intrinsic safety equally applies to proposed fourth-generation designs using uranium. It is also true that nuclear physics technicalities make thorium much less attractive for weapons production, but it is by no means impossible; the USA and USSR each tested a thorium-based atomic bomb in 1955.

Other perceived advantages similarly diminish under scrutiny. There is plenty of uranium ore in the world and hence the fourfold abundance advantage of thorium is a moot point. Producing less long-lived radioactive waste is certainly beneficial, but the vexed question remains of how to deal with it.

Stating that thorium is more efficiently consumed is the most mischievous of the claimed benefits. Fast-breeder uranium reactors have much the same fuel efficiency as thorium reactors. However, they weren’t economic as the price of uranium turned out to rather low.

May 19, 2018 Posted by | ANTARCTICA, Reference, thorium | Leave a comment

Disadvantages of thorium reactors

High start-up costs: Huge investments are needed for thorium nuclear power reactor, as it requires significant amount of testing, analysis and licensing work. Also, there is uncertainty over returns on the investments in these reactors. For utilities, this factor can weigh on the decisions to go ahead with plans to deploy the reactors. The reactors also involve high fuel fabrication and reprocessing costs.

High melting point of thorium oxide: As melting point of thorium oxide is much higher compared to that of uranium oxide, high temperatures are needed to make high density ThO2 and ThO2–based mixed oxide fuels. The fuel in nuclear fission reactors is usually based on the metal oxide.

Emission of gamma rays: Presence of Uranium-232 in irradiated thorium or thorium based fuels in large amounts is one of the major disadvantages of thorium nuclear power reactors. It can result in significant emissions of gamma rays. http://www.compelo.com/energy/news/newsmajor-pros-and-cons-of-thorium-nuclear-power-reactor-6058445/

May 19, 2018 Posted by | 2 WORLD, Reference, thorium | Leave a comment

Swizerland’s Health Office recalls jewellery contaminated with radioactive thorium and uranium

Radioactive jewellery recalled in Switzerland  swissinfo, 7 May 18 A Swiss company has sold esoteric “negative-ion” jewellery containing high levels of uranium and thorium. The Federal Office of Public Health has written to people who have bought the jewellery, telling them to send it to the health office.

Health office spokesman Daniel Dauwalder on Monday confirmed media reports that an unnamed company had imported rock powder from China with levels of the two radioactive substances that were harmful for skin cells and the outer skin layer.

The health office said if the bracelets, necklaces and earrings were worn for several hours a day over a year, the skin’s dose threshold of 50 millisieverts could be exceeded. In the long term, the risk of skin cancer would increase, it added.

….The radioactive rock powder was discovered by German customs guards, who informed the Federal Office of Public Health.

Dauwalder said the office had already received many items of jewellery, which would be disposed of accordingly. The jewellery must not end up in the normal rubbish, the office said.https://www.swissinfo.ch/eng/uranium-earrings_radioactive-jewellery-recalled-in-switzerland/44101980

 

May 9, 2018 Posted by | health, Switzerland, thorium | Leave a comment

Union of Concerned Scientists Statement on Thorium-fueled Reactors

  https://www.ucsusa.org/sites/default/files/legacy/assets/documents/nuclear_power/thorium-reactors-statement.pdf Some people advocate the use of thorium to fuel nuclear power plants. Thorium could be used in a variety of different types of reactors, including conventional light-water reactors, which are the type used in the United States. However, thorium cannot be used by itself to sustain a nuclear chain reaction: it must be used together with a fissile material such as enriched uranium, uranium-233, or plutonium.

 Nuclear reactors fueled with thorium and uranium do not provide any clear overall advantages over reactors fueled with uranium alone. All types of nuclear fuels, whether uranium- or thorium-based, generate large amounts of heat during reactor operation, and failing to effectively remove that heat will lead to serious safety problems, as was seen at Fukushima. The U.S. Department of Energy has concluded after a review that “the choice between uranium-based fuel and thorium-based fuel is seen basically as one of preference, with no fundamental difference in addressing the nuclear power issues [of waste management, proliferation risk, safety, security, economics, and sustainability].”1 However, the report also notes that “Since no infrastructure currently exists in the U.S. for thorium-based fuels, and the processing of thorium-based fuels is at a lower level of technical maturity when compared to processing of uranium-based fuels, costs and RD&D [research, development and deployment] requirements for using thorium are anticipated to be higher.”
Some people believe that liquid fluoride thorium reactors, which would use a high-temperature liquid fuel made of molten salt, would be significantly safer than current-generation reactors. However, such reactors have major flaws. There are serious safety issues associated with the retention of fission products in the fuel, and it is not clear these problems can be effectively resolved. Such reactors also present proliferation and nuclear terrorism risks because they involve the continuous separation, or “reprocessing,” of the fuel to remove fission products and to efficiently produce U-233, which is a nuclear weapon-usable material. Moreover, disposal of the used fuel has turned out to be a major challenge. Stabilization and disposal of the remains of the very small “Molten Salt Reactor Experiment” that operated at Oak Ridge National Laboratory in the 1960s has turned into the most technically challenging cleanup problem that Oak Ridge has faced, and the site has still not been cleaned up.

April 20, 2018 Posted by | 2 WORLD, thorium | Leave a comment

Poor financial results for thorium power industry

Thorium Power (NASDAQ:LTBR) last released its earnings results on Thursday, March 15th. The energy company reported ($0.18) earnings per share (EPS) for the quarter. Thorium Power had a negative net margin of 4,060.00% and a negative return on equity of 118.29%. The company had revenue of $0.01 million during the quarter. https://stocknewstimes.com/2018/04/07/lightbridge-ltbr-earning-somewhat-favorable-media-coverage-study-shows.html

April 14, 2018 Posted by | business and costs, thorium | Leave a comment

Despite the media hype, Thorium Power still a poor investment

Favorable Media Coverage Somewhat Unlikely to Impact Thorium Power (NASDAQ:LTBR) Stock Price, Weekly Herald, by Samantha Guadardo on Apr 10th, 2018 

News articles about Thorium Power (NASDAQ:LTBR) have been trending positive this week, according to Accern Sentiment. The research group identifies negative and positive press coverage by reviewing more than twenty million news and blog sources. Accern ranks coverage of publicly-traded companies on a scale of -1 to 1, with scores nearest to one being the most favorable. Thorium Power earned a media sentiment score of 0.25 on Accern’s scale. Accern also assigned news coverage about the energy company an impact score of 45.422705335828 out of 100, meaning that recent press coverage is somewhat unlikely to have an effect on the stock’s share price in the next several days.

LTBR stock opened at $1.15 on Tuesday. Thorium Power has a 12-month low of $0.94 and a 12-month high of $4.80.

April 11, 2018 Posted by | business and costs, thorium | Leave a comment

Thorium ‒ a better fuel for nuclear technology? 

  Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018 An important, detailed critique of thorium by Dr. Rainer Moormann, translated from the original German by Jan Haverkamp. Dr. Moormann concludes:

The use of technology based on thorium would not be able to solve any of the known problems of current nuclear techniques, but it would require an enormous development effort and wide introduction of breeder and reprocessing technology. For those reasons, thorium technology is a dead end.”

Author: Dr. Rainer Moormann, Aachen (r.moormann@gmx.deThorium is currently described by several nuclear proponents as a better alternative to uranium fuel.

Thorium itself is, however, not a fissile material. It can only be transformed into fissile uranium-233 using breeder and reprocessing technology. It is 3 to 4 times more abundant than uranium.

Concerning safety and waste disposal there are no convincing arguments in comparison to uranium fuel. A severe disadvantage is that uranium-233 bred from thorium can be used by terror organisations for the construction of simple but high-impact nuclear explosives. Thus development of a thorium fuel cycle without effective denaturation of bredfissile materials is irresponsible.

Introduction

Thorium Introduction 

Thorium (Th) is a heavy metal of atomic number 90

(uranium has 92). It belongs to the group of actinides, is

around 3 to 4 times more abundant than uranium and is

radioactive (half-life of Th-232 as starter of the thorium

decay-chain is 14 billion years with alpha-decay). There

are currently hardly any technical applications. Distinctive

is the highly penetrating gamma radiation from its decaychain

(thallium-208 (Tl-208): 2.6 MeV; compared to

gamma radiation from Cs-137: 0.66 MeV). Over the past

decade, a group of globally active nuclear proponents is

recommending thorium as fuel for a safe and affordable

nuclear power technology without larger waste and

proliferation problems. These claims should be submitted

to a scientific fact check. For that reason, we examine

here the claims of thorium proponents.

Dispelling Claim 1: The use of thorium expands the

availability of nuclear fuel by a factor 400  

Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018

Thorium itself is not a fissile material. It can, however, be

transformed in breeder reactors into fissile uranium-233

(U-233), just like non-fissile U-238 (99.3% of natural

uranium) can be transformed in a breeder reactor to fissile

plutonium. (A breeder reactor is a reactor in which more

fissile material can be harvested from spent nuclear fuel

than present in the original fresh fuel elements. It may be

sometimes confusing that in the nuclear vocabulary every

conventional reactor breeds, but less than it uses (and

therefore it is not called a breeder reactor).)

For that reason, the use of thorium presupposes the use

of breeder and reprocessing technology. Because these

technologies have almost globally fallen into disrepute, it

cannot be excluded that the more neutral term thorium is

currently also used to disguise an intended reintroduction

of these problematic techniques.

The claimed factor 400: A factor of 100 is due to the

breeder technology. It is also achievable in the uraniumplutonium

cycle. Only a factor of 3 to 4 is specific to

thorium, just because it is more abundant than uranium

by this factor…….

March 5, 2018 Posted by | 2 WORLD, ENERGY, Reference, thorium | Leave a comment

It’s a myth that thorium nuclear reactors were ever commercially viable

Dispelling Claim 2: Thorium did not get a chance in the  nuclear energy development because it is not  usable for military purposes   Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018

In the early stages of nuclear technology in the USA (from 1944 to the early 1950s), reprocessing technology was not yet well developed. Better developed were graphite moderated reactors that used natural uranium and bred plutonium.

For the use of thorium (which, other than uranium, does not contain fissile components), enriched uranium or possibly plutonium would have been indispensable.

Initially, neither pathway for thorium development was chosen because it would have automatically reduced the still limited capacity for military fissile materials production. (Thorium has a higher capture cross section for thermal (that means slow) neutrons than U-238. For that reason, it needs as fertile material in reactors a higher fissile density than U-238.)

Only when the US enrichment capacity at about 1950 delivered sufficient enriched uranium, the military and later civil entry into thorium technology started: in 1955 a bomb with U-233 from thorium was exploded, and a strategic U-233 reserve of around 2 metric tons was created. The large head-start of the plutonium bomb could not be overtaken any more, and plutonium remained globally the leading military fission material (although, according to unconfirmed sources, Indian nuclear weapons contain U-233).

The US military research concluded in 1966 that U-233 is a very potent nuclear weapon material, but that it offers hardly any advantages over the already established plutonium. Because light water reactors with low-enriched uranium (LEU) were already too far developed, thorium use remained marginal also in civil nuclear engineering: for instance, the German “thorium reactor” THTR-300 in Hamm operated only for a short time, and in reality it was a uranium reactor (fuel: 10% weapon-grade 93% enriched U-235 and 90% thorium) because the amount of energy produced by thorium did not exceed 25%.

 

March 5, 2018 Posted by | 2 WORLD, business and costs, Reference, spinbuster, thorium | Leave a comment

The weapons proliferation risks of thorium nuclear reactors

Dispelling Claim 3: Thorium use has hardly any proliferation risk   Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018

The proliferation problem of Th / U-233 needs a  differentiated analysis ‒ general answers are easily misleading. First of all, one has to assess the weapon capability of U-233. Criteria for good suitability are a low critical mass and a low rate of spontaneous fission. The critical mass of U-233 is only 40% of that of U-235, the critical mass of plutonium-239 is around 15% smaller than for U-233. A relatively easy to construct nuclear explosive needs around 20 to 25 kg U-233.

The spontaneous fission rate is important, because the neutrons from spontaneous fission act as a starter of the chain reaction; for an efficient nuclear explosion, the fissile material needs to have a super-criticality of at least 2.5 (criticality is the amount of new fissions produced by the neutrons of each fission.)

When, because of spontaneous fissions, a noticeable chain reaction already starts during the initial conventional explosion trigger mechanism in the criticality phase between 1 and 2.5, undesired weak nuclear explosions would end the super-criticality before a significant part of the fissile material has reacted. This largely depends on how fast the criticality phase of 1 to 2.5 is passed. Weapon plutonium (largely Pu-239) and moreover reactor plutonium have – different from the mentioned uranium fission materials U-235 and U-233 – a high spontaneous fission rate, which excludes their use in easy to build bombs.

More specifically, plutonium cannot be caused to explode in a so-called gun-type fission weapon, but both uranium isotopes can. Plutonium needs the far more complex implosion bomb design, which we will not go into further here. A gun-type fission weapon was used in Hiroshima – a cannon barrel set-up, in which a fission projectile is shot into a fission block of a suitable form so that they together form a highly super-critical arrangement.   Here, the criticality phase from 1 to 2.5 is in the order of magnitude of milliseconds – a relatively long time, in which a plutonium explosive would destroy itself with weak nuclear explosions caused by spontaneous fission.

One cannot find such uranium gun-type fission weapons in modern weapon arsenals any longer (South Africa’s apartheid regime built 7 gun-type fission weapons using uranium-235): their efficiency (at most a few percent) is rather low, they are bulky (the Hiroshima bomb: 3.6 metric tons, 3.2 meters long), inflexible, and not really suitable for carriers like intercontinental rockets.

On the other hand, gun-type designs are highly reliable and relatively easy to build. Also, the International Atomic Energy Agency (IAEA) reckons that larger terror groups would be capable of constructing a nuclear explosive on the basis of the gun-type fission design provided they got hold of a sufficient amount of suitable fissile material.1

Bombs with a force of at most 2 to 2.5 times that of the Hiroshima bomb (13 kt TNT) are conceivable. For that reason, the USA and Russia have tried intensively for decades to repatriate their world-wide delivered highly enriched uranium (HEU).

A draw-back of U-233 in weapon technology is that – when it is produced only for energy generation purposes – it is contaminated with maximally 250 parts per million (ppm) U-232 (half-life 70 years).2 That does not impair the nuclear explosion capability, but the uranium-232 turns in the thorium decay chain, which means ‒ as mentioned above ‒ emission of the highly penetrating radiation of Tl-208. A strongly radiating bomb is undesirable in a military environment – from the point of view of handling, and because the radiation intervenes with the bomb’s electronics.

In the USA, there exists a limit of 50 ppm U-232 above which U-233 is no longer considered suitable for weapons.

Nevertheless, U-232 does not really diminish all proliferation problems around U-233. First of all, simple gun-type designs do not need any electronics; furthermore, radiation safety arguments during bomb construction will hardly play a role for terrorist organisations that use suicide bombers.

Besides that, Tl-208 only appears in the end of the decay chain of U-232: freshly produced or purified U-233/U-232 will radiate little for weeks and is easier to handle.2 It is also possible to suppress the build-up of uranium-232 to a large extent, when during the breeding process of U-233 fast neutrons with energies larger than 0.5 MeV are filtered out (for instance by arranging the thorium in the reactor behind a moderating layer) and thorium is used from ore that contains as little uranium as possible.

A very elegant way to harvest highly pure U-233 is offered by the proposed molten salt reactors with integrated reprocessing (MSR): During the breeding of U-233 from thorium, the intermediate protactinium-233 (Pa-233) is produced, which has a half-life of around one month. When this intermediate is isolated – as is intended in some molten salt reactors – and let decay outside the reactor, pure U-233 is obtained that is optimally suited for nuclear weapons.

An advantage of U-233 in comparison with Pu-239 in military use is that under neutron irradiation during the production in the reactor, it tends to turn a lot less into nuclides that negatively influence the explosion capability. U-233 can (like U-235) be made unsuitable for use in weapons by adding U-238: When depleted uranium is already mixed with thorium during the feed-in into the reactor, the resulting mix of nuclides is virtually unusable for weapons.

However, for MSRs with integrated reprocessing this is not a sufficient remedy. One would have to prevent separation of protactinium-233.9

The conclusion has to be that the use of thorium contains severe proliferation risks. These are less in the risk that highly developed states would find it easier to lay their hands on high-tech weapons, than that the bar for the construction of simple but highly effective nuclear explosives for terror organisations or unstable states will be a lot lower.

 

March 5, 2018 Posted by | Reference, spinbuster, thorium, weapons and war | Leave a comment

Thorium nuclear reactors: no safer than conventional uranium reactors

Dispelling Claim 4: Thorium reactors are safer than  conventional uranium reactors  Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018

The fission of U-233 results in roughly the same amounts

of the safety-relevant nuclides iodine-131, caesium-137

and strontium-90 as that of U-235. Also, the decay heat is

virtually the same. The differences in produced actinides (see

next claim) are of secondary importance for the risk during

operation or in an accident. In this perspective, thorium use

does not deliver any recognisable safety advantages.

Of greater safety relevance is the fact that uranium-233

fission produces 60% less so-called delayed neutrons than

U-235 fission. Delayed neutrons are not directly created

during the fission of uranium, but from some short-lived

decay products. Only due to the existence of delayed

neutrons, a nuclear reactor can be controlled, and the

bigger their share (for instance 0.6% with U-235), the

larger is the criticality range in which controllability is given

(this is called delayed criticality). Above this controllable

area (prompt criticality) a nuclear power excursion can

happen, like during the Chernobyl accident. The fact that

the delayed super-critical range is with U-233 considerably

smaller than with U-235, is from a safety point of view an

important technical disadvantage of thorium use.

During the design of thermal molten salt reactors (breeders),

the conclusion was that the use of thorium brings problems

with criticality safety that do not appear with classical

uranium use in this type of reactors. For that reason, it was

necessary to turn the attention to fast reactors for the use

of thorium in molten salt reactors. Although this conclusion

cannot be generalised, it shows that the use of thorium can

lead to increased safety problems.

As mentioned, a serious safety problem is the necessity to

restart breeder and reprocessing technology with thorium.

Thorium is often advertised in relation to the development

of so-called advanced reactors (Generation IV). The

safety advantages attributed to thorium in this context are

mostly, however, not germane to thorium (the fuel) but

rather due to the reactor concept. Whether or not these

advanced reactor concepts bring overall increased safety

falls outside the scope of this article, but that is certainly

not a question with a clear “yes” as the answer.

March 5, 2018 Posted by | 2 WORLD, Reference, safety, spinbuster, thorium | Leave a comment

Thorium reactors – NOT a solution to nuclear waste problem

Dispelling Claim 5: Thorium decreases the waste problem  

Thorium ‒ a better fuel for nuclear technology? Nuclear Monitor,   by Dr. Rainer Moormann  1 March 2018

Thorium use delivers virtually the same fission products

as classical uranium use. That is also true for those

isotopes that are important in issues around long-term

disposal.  Those mobile long-lived fission products

(I-129, Tc-99, etc.) determine the risk of a deep geological

disposal when water intrusion is the main triggering event

for accidents. Thorium therefore does not deliver an

improvement for final disposal.

Proponents of thorium argue that thorium use does not

produce minor actinides (MA)5, nor plutonium. They argue

that these nuclides are highly toxic (which is correct) and

they compare only the pure toxicity by intake into the body

for thorium and uranium use, without taking into account

that these actinides are hardly mobile in final disposal

even in accidents.

March 5, 2018 Posted by | 2 WORLD, Reference, spinbuster, thorium, wastes | Leave a comment

The Thorium lobby – religious fervour in attacking critics of the nuclear industry

Thorium Church: a trojan horse in the “green” movements. Here the Removal Tool.   How do I know if my preferred “green” organization, or group, or leader… is infected by the ‘thorium church’ trojan horse?”. How to protect yourself from malicious propaganda of Thorium Church or from related compromised group or organizations. nonukes Italy, By Massimo Greco (June 2015)

What are trojan horses?

Trojan horses, otherwise known as trojans, are programs or applications that are inadvertently opened by the user, who expects the file to be something else..  by the same way “thorium supporters” are infecting forums, mailing list, debacts and environmental organizations.

It’s a strategy that is working in progress from some year. In few years they infected large part of the web. 

Like any malware, thorium’s priests are insinuated through any open space or open port .. and they are able to act at different levels. Mutating depending on the circumstances, improvising them selves as technicians or economists with the sole purpose of creating deviationism which in practice consists of annoying redirect to their cause that is regularly touted as a “green” solution or, even, “pacifist” or as a miraculous solution for the “salvation of the climate”.

Their function is aggressive, especially when you try to contradict them. Continue reading

March 2, 2018 Posted by | 2 WORLD, Reference, secrets,lies and civil liberties, spinbuster, thorium | 1 Comment

Scan your environmental group for “thorium troll” infection

 nonukes Italy, By Massimo Greco (June 2015) “How do I know if my preferred “green” organization, or group, or leader… is infected by the ‘thorium church’ trojan horse?”

“……..Scanning and Removal, First check if the leader or “group leader” you are referring knows the problem of thorium, whether it has never taken a position on it. If the answer is “I do not know the problem” or “what you’re talking about,” you have the first certainty that your organization or target group is NOT protected.

If the answer is: “It is not a problem that concerns us”, “there is no matter in our topic or with antinuclear matter or uranium …”, or even worse … “nuclear thorium could be a clean way but the NWO prevents “… then you have the most certain that your group or environmental organization is terribly infected and that the leader is highly compromised.

If you are doing this survey “in public”, in a forum related to your organization reference, and after posting these sacrosanct questions and you are reproached or assaulted without causing or leading an intervention by the “admin” able to defend you, that’s another proof that your organization, or environmental group, results hugely infected.

You can also do a very easy search to see if the “admin” or the “most active” subjects are related to pro-thorium forums or registered as supporters of fan in groups offering thorium as a “savior” or “green”, especially when you attend to spam and suspicious behavior in the forums or social networks. You can do the same search about chemtrails or “HAARP” deviationism. As better Explained before, Thorium Church used very much the conspiracy decoy in order to mislead, confused and make it weak, vulnerable and unpractical environmental movements.

How to protect yourself from malicious propaganda of Thorium Church or from related compromised group or organizations.

If, as explained above, your reference group or environmental organization is infected: leave the group. This way you will avoid being accomplices. Thou hast tried, you have already taken the necessary steps. You’re not responsible. You have tried to change things.

If you are a “leader” or admin of a forum, or group… or green or environmental organization, you have to eject such people before they get completely the control of any topic. You have the duty to eject these individuals, without any hesitation of “democracy” and “freedom of confusion”… Because they, in the spaces controlled by the Thorium Church, do not allow you ever to contradict them and erase systematically, as their typical practice, anything that might cast doubt on their truth or propaganda. And, in any case, as admin or “leader” you have a duty to treat these subjects like any nuclearist that want to provoke discussion on the space that you are owning, or controlling.

If you are owning a youtube channel or any social page on social networks and you want to get protection from the thorium worm.. specially concerning antinuclear or environmental documents:

Simply “turn off” the option about “free comments” and choice comments under authorization or moderate. If you are admin of social pages delete their worms (spamming) and eject the vehicle of infection (for the reasons better explained before).

“How can I become active against cultural damages of pro-nuclear business propaganda of the Thorium Church?”

Ofcourse there are many different ways. Remember that pro-nuclear lobbies are pushing for the “new generation of nuclear power”, that means not only tradicional way of uranium. In fact they are talking about “nuclear of future”. So, “green”, environmentalist organizations, antinuclear people need to look about future strategies of the lobbies and not only to the past or the temporary, local, contingencies.

In recent years many antinuclear resources and internationally famous have taken a position on thorium. Just think about documents released by Bellona, Beyond Nuclear or to the Excellent article from Bob Alvarez on why thorium is not the wonder fuel it’s being promoted as and a brief history of the US’s persistent failure in making thorium safe or efficient ending with the expected trail of dangerous, weaponizable, waste… or the position of Helen Caldicott, violently attacked by the priests of the Thorium Church with a lot of insults like at the time of the “Scarlet Letter”…

[Dr. Arjun Makhijani on the downsides of the proposed thorium reactors (by Dr. Helen Caldicott)]

So it’s important to diffuse all the events, documents and positions, everywhere is possible, in order to counteract the mala information and debunking thorium commercials spot on the net.

To start an international and active support of the antinuclear movement in Indonesia, Malaysia, specially concerning the mobilization around Lynas, Koodankulam and any Rare Earth opposition in the West Asia. Promoting an active “UPGRADE” of all the antinuclear organizations.

Not only. You can help also supporting all the RNA spaces. Like this. For a new “NoThorium” activism. RNA was the first organization that started activism against thorium in Italy and in Paris. And at this moment has and diffuses the most rich archive of documents against thorium.

Better active today than radioactive tomorrow http://www.nonukes.it/rna/news326.html

March 2, 2018 Posted by | Reference, secrets,lies and civil liberties, spinbuster, thorium | Leave a comment