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Blunderov
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Revolutionary Thorium Reactor
« on: 2009-06-29 16:37:14 » |
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[Blunderov] ISTM the future is nuclear. This type seems to be the best of all possible worlds. Why is this technology not already sweeping all before it?
Revolutionary Thorium Reactor - The most environmentally beneficial power source on earth
Source: opednews
Author: by Christopher Calder
Dated: June 28, 2009 at 22:12:42
There are many so-called "Generation IV" nuclear reactor designs being studied to replace the world's aging fleet of light water nuclear power plants. Light water nuclear reactors use ordinary H2O to moderate nuclear fission, for cooling, and to create steam for running turbines. All of the newer reactor designs have clear advantages over the old light water standard. China and South Africa are rapidly perusing meltdown proof pebble bed reactor technology, and the Idaho National Laboratory is experimenting with prismatic block reactors, reported to be even more efficient and stable. Most of the proposed new designs represent evolutionary improvements, but the LFT (liquid fluoride thorium) reactor design is truly revolutionary. LFT reactors are an earth friendly power source that solves all of the major problems associated with nuclear power.
LFT reactors transform thorium into fissionable uranium-233, which then produces heat through controlled nuclear fission. The reactor only requires input of uranium to kick-start the initial nuclear reaction, and as the uranium can come from spent nuclear fuel rods, LFT reactors will inevitably be used as janitors to clean up nuclear waste. Once started, the controlled nuclear reactions are self-perpetuating as long as the reactor is fed thorium. As the fuel is a molten liquid salt, it can be cleansed of impurities and refortified with thorium through elaborate plumbing, even while the reactor maintains full power operation. This reduces reactor downtime and increases total yearly energy output.
LFT reactors produce electric power via a waterless gas turbine system that can use helium, carbon dioxide, or nitrogen gas. The reactors are small and air cooled, so they can be installed anywhere, even in a desert. Robert Hargraves, an LFT advocate, states that "Liquid fluoride thorium reactors operate at high temperature for 50% thermal/electrical conversion efficiency, thus they need only half of the cooling required by today's coal or nuclear plant cooling towers." LFT reactors will be manufactured on an assembly line, dramatically lowering costs and enabling electricity generation at a projected rate of about 3 cents per kilowatt hour. It has been estimated that a physically small 100 megawatt LFT reactor would cost less than 200 million dollars to build, which is a bargain. Multiple reactors can be installed at one location and connected to a single control room. With convenient modular design, LFT reactors can be transported in pieces by truck or barge for easy assembly on site. This allows for swift construction with reliable results, avoiding delays and cost overruns. Rapid assembly line construction also allows for easy updating of the design, which will get better and better, like the evolution of automobiles, airplanes, and computer chips.
LFT reactors are much more fuel efficient than other designs, because they burn up 100% of the thorium fed them. Light water reactors typically burn only about 3% of their loaded fuel, or about .7% of the fundamental raw uranium, which must be enriched to become fissionable. Because of their high energy conversion efficiency, LFT reactors produce less than 1% of the long lasting radioactive waste of light water reactors, making the controversial Yucca Mountain Repository for nuclear waste unnecessary.
A LFT reactor can never meltdown, because its fuel is already in a molten state by design. Any terrorists who obtained forceful entry into the reactor complex could not realistically remove any of the hot molten fissionable fuel. Coolant in LFT reactors is not pressurized as in light water reactors, and the fuel arrives at the plant pre-burned with fluorine, a powerful oxidizer. This makes a reactor fire or a coolant explosion impossible. LFT reactors do not require large, cavernous pressure vessels designed to contain an internal explosion of superheated steam, so LFT enclosures are tightly fitting and compact, which makes them less expensive to build. The reactors will be installed underground with a thick reinforced concrete cap, making an attack by a kamikaze airplane pilot ineffective. Overheating of a LFT reactor expands the molten salt fuel past its criticality point, making the design intrinsically safe due to the unchangeable laws of physics. Even a total loss of operational reactor control would not cause disaster. In addition to the fuel's natural safety, any excess heat in the reactor core would automatically melt a built-in freeze-plug, causing the liquid fuel to drain via gravity into underground storage compartments, where the fuel would then cool into a harmless, noncritical mass.
We have enormous amounts of low cost thorium fuel available, with estimates of efficiently recoverable reserves ranging from a supply lasting thousands of years, to a supply lasting over 2 million years. LFT reactors can be used to manufacture synthetic gasoline made from atmospheric CO2 and water, or can produce high energy methanol fuel. The French Reactor Physics Group is leading in LFT research, and there are LFT experiments being conducted in Japan, the Netherlands, Russia, and in the Czech Republic. If the U.S. Government committed a relatively modest amount of money to LFT research in cooperation with France, a fully operational TOTAL ENERGY SOLUTION might be possible within as little as 5 years, because most of the basic research has already been accomplished and is well proven. LFT research at Oak Ridge National Laboratory was ended in 1976, because the reactor's design cannot practically produce weapons grade plutonium. LFT reactors will not lead to the proliferation of nuclear weapons.
LFT technology will have a very small footprint on planet earth, unlike renewable energy schemes that use up impossibly large amounts of land and vital resources. Scientist Jesse H. Ausubel, Director of the Program for the Human Environment, found that to meet U.S. electricity demand for 2005 with wind power would require about four million megawatt hours of electricity. Even with impossible around-the-clock-winds, he calculated this would require a wind farm covering over 301,159 square miles, which is about the size of Texas and Louisiana combined. It has been proven by real-world experience that solar and wind power schemes are far more costly than a simple price per kilowatt hour comparison would suggest. Their unreliable on-again, off-again nature requires huge backup power reserves from other energy sources, which greatly increases costs.
The Energy Information Administration, which provides official energy statistics from the U.S. Government, has projected the estimated cost of electricity from U.S. power plants of different varieties that will come into service in the year 2016. These average levelized costs, expressed in 2007 valued dollars, includes all costs of construction, financing, fuel, and all other operating costs. The EIA also listed the expected Capacity Factor (CF) for each power plant type. A power plant with a CF of 85 generates energy at its rated capacity an average of 85% of the time during a given year. The ideal power plant would have a CF of 100, meaning it could output energy at full power 100% of the time. As capacity factor drops, economic efficiency drops, usefulness drops, and real-world costs increase. In the comparison below I have inflated the projected cost of electricity produced by LFT reactors from the projected 3 cents per kilowatt hour (kWh) to 6 cents per kWh in order to allow for unexpected cost overruns.
Natural Gas in Conventional Combined Cycle @ 8.34 cents per kWh (87 CF) - Not carbon free; small footprint; cost effective and cleanest fossil fuel available.
Conventional Coal @ 9.3 per cents per kWh (85 CF) - Not carbon free; medium footprint; causes approximately 24,000 U.S. deaths per year due to air pollution, which also damages buildings. Judged in total, coal is not cost effective due to the environmental damage it creates.
3rd Generation Light Water Reactor Nuclear Power @ 10.48 cents per kWh (90 CF) - Carbon free; small footprint and cost effective.
Geothermal @ 11.67 cents per kWh (90 CF) - Carbon free; small footprint and cost effective.
Wind @ 11.55 cents per kWh (35.1 CF) - Carbon free; extremely large footprint; not cost effective due to unreliability and very low CF.
Solar Thermal Mirror Oven @ 25.75 cents per kWh (31.2 CF) - Carbon free; extremely large footprint; not cost effective due to unreliability, high construction cost, and very low CF.
Solar Photovoltaic Panel Power Plant @ 38.54 cents per kWh (21.7 CF) - Carbon free; extremely large footprint; very high construction cost; cannot be updated after manufacture; relatively short lifespan; solar panels are not cost effective for large scale power production.
LFT Nuclear Reactor @ 6.0 cents per kWh (over 90 CF) - Carbon free; small footprint; highest CF available; highest cost effectiveness. If things go well, the actual eventual cost per kWh may be at or close to the original 3 cents per kWh projection, which would be wonderful. LFT technology's tiny ecological footprint on planet earth makes it the most environmentally harmless energy source available.
Reference links:
Aim High (brief overview) - http://rethinkingnuclearpower.googlepages.com/aimhigh
Aim High slide show on 3.2MB PDF - http://home.comcast.net/~robert.hargraves/public_html/AimHigh.pdf
Energy from Thorium - http://thoriumenergy.blogspot.com/
The Liquid Fluoride Thorium Paradigm - http://www.theoildrum.com/node/4971
French Reactor Physics Group - http://lpsc.in2p3.fr/gpr/gpr/
EIA Annual Energy Outlook 2009 - http://www.eia.doe.gov/oiaf/aeo/index.html
Turning nuclear power into gasoline - http://www.lanl.gov/news/newsbulletin/pdf/Green_Freedom_Overview.pdf
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Fritz
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Re:Revolutionary Thorium Reactor
« Reply #1 on: 2009-06-29 16:53:49 » |
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This one snuck up on me; thx Blunderov. I was curious to see if CANDU and Bechtel are in the mix and sure enough found the attached.
Cheers
Fritz
Source: thoriumenergey Inc.
Author=n/a
Date: Tuesday, June 16, 2009 19:56 IST
http://www.dnaindia.com/india/report_nuke-dealmovingsatisfactorilykakodkar_1265502
Kolkata: After becoming operational, the Indo-US civil nuclear deal is moving "satisfactorily"
with the government now negotiating with nuclear vendors, Atomic Energy Commission chairman
Anil Kakodkar said on Tuesday.
_____________________________________________________________
US nuclear mission to visit India
6 Jan 2009, 0011 hrs IST, Shalini Singh, TNN New Delhi - The Americans are coming. India is to receive its first commercial nuclear mission after the signing of its historic nuclear deal with the US on October 11, 2008 in Washington The intent of this visit is to establish an advantage in the projected $150 billion business potential with India. It is learnt that the US India Business Council (USIBC) and NEI is bringing the largest trade mission ever to visit India over the next few days. While details of the delegations agenda while in India are still under wraps, it is expected that it will meet with senior Indian government officials, the leaders of India's top public-sector undertakings, and senior executive counterparts from Indian companies. The mission includes over 50 senior US commercial nuclear executives representing more than 30 of the world's leading commercial nuclear companies including General Electric, Westinghouse, Bechtel Nuclear, The Shaw Group, Babcock &Wilcox, Black & Veatch, CH2M Hill, Uranium One, Thorium Power, and USEC, among others. The Indo-US nuke deal was historic, marking the end of 34 years of US sanctions on nuclear trade with India, as well as a turning point in the bilateral relationship of these two democracies. The landmark deal also unleashes billions of dollars of investment between India and the West. According to the CII, the agreement could open up around $27 billion in investments in 18-20 nuclear plants over the next 15 years, while lobby group Imagindia Institute has said the overall economic benefits accruing to India's economy as a result of nuclear trade could touch $500 billion by 2030. According to a Reuters report, the deal is expected to double nuclear power's share in India's electricity supply to up to 7% in the next two decades. With nuclear fuel in short supply, India's nuclear power plants are running at 55% of their capacity of about 4,000 megawatts. India's electricity supply, about 15% short of demand in peak hours is also expected to get a boost, but any new nuclear power plant may take a decade to be completed, leaving the country dependent of coal and liquid fuels. Formed in 1975 under the aegis of the US Chamber of Commerce, USIBC is a business advocacy organization representing 300 of the largest US companies investing in India, joined by global Indian companies, seeking deeper US-India commercial ties. The Nuclear Energy Institute (NEI) is the policy organisation of the nuclear energy and technologies industry that seeks to ensure the formation of policies promoting the beneficial uses of nuclear energy and technologies in the US and around the world. According to the USIBC, the US commercial nuclear industry leads the world in size, performance, innovation, and engineering worldwide. The US is the largest generator of electric power in the world with 27% of the world's total installed capacity and nearly double the number of reactors as France. India committed to developing thorium reactors: NPCIL chief 03 December 2008 India is committed to the three-stage nuclear power development programme involving the use of pressurized heavy water reactors, the fast breeder reactors and the thorium reactors, according to Nuclear Power Corporation chairman and managing director S K Jain. While the recent nuclear power deals have opened up a plethora of opportunities for the Indian industry in the field of nuclear power, much will still remain in the state domain, Jain said in a paper released at the recently concluded annual conference of the Indian Nuclear Society. He said while the Atomic Energy Commission (AEC) has identified some PHWRs to be put in civilian domain, some are not. These would feed the subsequent development, the fast reactors, the interconnecting fuel cycle, that means the reprocessing plants and then when you go to the third stage the thorium reactors and the related fuel cycle, he added. The DAE has reaffirmed its commitment to thorium fuel cycle, proposing to construct a dozen indigenously-developed nuclear power reactors. These units will be supplemented by imported conventional reactors, he said. ''This is still a technology in evolution and because we want to evolve the technology to a level of commercial robustness of global competitive level, we want to be able to do this on our own and so we need to protect this development from external vulnerabilities and so it is outside the civilian domain,'' Jain said. NPCIL will start site work next year for 12 indigenously-developed reactors, including eight pressurized heavy water reactors of 700 MWe each, three 500 MWe fast breeder reactors (FBRs) and one 300 MWe advanced heavy water reactor (AHWR), as part of the 11th plan (2007-12) programme, Jain said. This will take forward India's long-standing commitment to the thorium fuel cycle, notwithstanding the opening up of trade in uranium and conventional nuclear technology, he said. The eight PHWRs were supposed to have been in the last five year plan, but constraints on uranium mining in India delayed them and set back the overall schedule, Jain said. "India is now focusing on capacity addition through indigenization" with progressively higher local content for imported designs, up to 80 per cent, he said. NPCIL, Jain said, plans to construct 25-30 light water reactors of at least 1000 MWe by 2030, and is currently identifying coastal sites for the first of these, both 1000 and 1650 MWe types. Long term, the AEC envisages its fast reactor programme being 30 to 40 times bigger than the present PHWR programme, which has some 4.4 GWe operating or under construction and 5.6 GWe planned. This 40 GWe of imported LWR multiplied to 400 GWe via FBR synergy would complement 200-250 GWe based on the indigenous programme of PHWR-FBR-AHWR. Thus, AEC expects developing reactors of about 500 to 600 GWe over the next 50 years. ''This programme which is not a part of the civilian domain and that programme is not going to be small. That programme is going to be large because the ultimate energy independence for the country would come about through the three stage nuclear power programme. This programme has to be autonomous since there is parallel elsewhere and there is no other solution either,'' he said. We are talking about four more FBRs to follow immediately after PFBR. We are talking about a fast breeder programme which may well be 30-40 times larger than PHWR programme and a good part of that we would have to keep outside the civil domain till we are sure about a synchronized working of the reprocessing plant and the reactor plant with commercial efficiency and assurance, he added. India has a flourishing and largely indigenous nuclear power program and expects to have 20,000 MWe nuclear capacity on line by 2020. It aims to supply 25% of electricity from nuclear power by 2050. Because India is outside the Nuclear Non-Proliferation Treaty due to its weapons program, it has been for 34 years largely excluded from trade in nuclear plant or materials, which has hampered its development of civil nuclear energy. Due to these trade bans and lack of indigenous uranium, India has uniquely been developing a nuclear fuel cycle to exploit its reserves of thorium. From 2008, foreign technology and fuel are expected to boost India's nuclear power plans considerably. India has a vision of becoming a world leader in nuclear technology due to its expertise in fast reactors and thorium fuel cycle. Thorium cycle development The long-term goal of India's nuclear program is to develop an advanced heavy-water thorium cycle.This first employs the PHWRs fuelled by natural uranium, and light water reactors, to produce plutonium. Stage 2 uses fast neutron reactors burning the plutonium to breed U-233 from thorium. The blanket around the core will have uranium as well as thorium, so that further plutonium (ideally high-fissile Pu) is produced as well as the U-233. Then in stage 3, Advanced Heavy Water Reactors (AHWRs) burn the U-233 and this plutonium with thorium, getting about two thirds of their power from the thorium. In 2002 the regulatory authority issued approval to start construction of a 500 MW prototype fast breeder reactor at Kalpakkam and this is now under construction by BHAVINI. The unit is expected to be operating in 2010, fuelled with uranium-plutonium oxide (the reactor-grade Pu being from its existing PHWRs). It will have a blanket with thorium and uranium to breed fissile U-233 and plutonium respectively. This will take India's ambitious thorium program to stage 2, and set the scene for eventual full utilisation of the country's abundant thorium to fuel reactors. Four more such fast reactors have been announced for construction by 2020. Initial FBRs will be have mixed oxide fuel but these will be followed by metallic-fuelled ones to enable shorter doubling time. India has six reactors under construction and expected to be completed by 2010. This includes two large Russian reactors and a large prototype fast breeder reactor as part of its strategy to develop a fuel cycle which can utilise thorium. Further units are planned. Ten further units are planned, and plans for more - including western and Russian designs - are taking shape following the lifting of trade restrictions. (November 2008) India has a flourishing and largely indigenous nuclear power program and expects to have 20,000 MWe nuclear capacity on line by 2020. It aims to supply 25% of electricity from nuclear power by 2050. Because India is outside the Nuclear Non-Proliferation Treaty due to its weapons program, it has been for 34 years largely excluded from trade in nuclear plant or materials, which has hampered its development of civil nuclear energy. Due to these trade bans and lack of indigenous uranium, India has uniquely been developing a nuclear fuel cycle to exploit its reserves of thorium.
From 2008, foreign technology and fuel are expected to boost India's nuclear power plans considerably. India has a vision of becoming a world leader in nuclear technology due to its expertise in fast reactors and thorium fuel cycle. A. P. J. Abdul Kalam Tuesday, Dec 04, 2007
HYDERABAD: Former President A.P.J. Abdul Kalam has advised nuclear scientists to work with perseverance for generating nuclear power through thorium route. “That will be the eventual answer for meeting our needs from clean sources,” he said.
Replying to a question on the nuclear deal with the US after delivering the keynote address at the annual Google India Conference here on Monday, he said:
"When political leaders are busy in debating about the treaty, my advice to the nuclear scientists would be to design and develop thorium-based nuclear reactor and operationalise it within the next five years. Simultaneously, he said, work had to be done on generating large quantity of power through solar and wind energy"
In India, both Kakrapar-1 and -2 units are loaded with 500 kg of thorium fuel in order to improve their operation when newly-started. Kakrapar-1 was the first reactor in the world to use thorium, rather than depleted uranium, to achieve power flattening across the reactor core. In 1995, Kakrapar-1 achieved about 300 days of full power operation and Kakrapar-2 about 100 days utilizing thorium fuel. The use of thorium-based fuel was planned in Kaiga-1 and -2 and Rajasthan-3 and -4 (Rawatbhata) reactors. With about six times more thorium than uranium, India has made utilisation of thorium for large-scale energy production a major goal in its nuclear power program, utilizing a three-stage concept: Pressurized Heavy Water Reactors (PHWRs, elsewhere known as CANDUs) fueled by natural uranium, plus light water reactors, produce plutonium.
Fast Breeder Reactors (FBRs) use this plutonium-based fuel to breed U-233 from thorium. The blanket around the core will have uranium as well as thorium, so that further plutonium (ideally high-fissile Pu) is produced as well as the U-233.
Advanced Heavy Water Reactors burn the U-233 and this plutonium with thorium, getting about 75% of their power from the thorium. The spent fuel will then be reprocessed to recover fissile materials for recycling.
This Indian program has moved from aiming to be sustained simply with thorium to one "driven" with the addition of further fissile uranium and plutonium, to give greater efficiency.
Source: World Nuclear Association
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Hermit
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Re:Revolutionary Thorium Reactor
« Reply #2 on: 2009-06-29 18:54:27 » |
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[Blunderov] Why is this technology not already sweeping all before it?
[Hermit]
Perhaps because the Devil is always in the details. In this case, the detail is that fluorine salts are nasty (!) and they have to be kept really pure or they can turn into hydrofluoric acid which gets frighteningly close to the alchemists "universal solvent" (which of course could be safely stored only in a solution of supersaturated universal solvent).
We know how to purify the salts required in lab quantities, but not at production quantities and not at an affordable cost.
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Blunderov
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Re:Revolutionary Thorium Reactor
« Reply #3 on: 2009-06-30 04:28:43 » |
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Quote from: Hermit on 2009-06-29 18:54:27
[Blunderov] Why is this technology not already sweeping all before it?
[Hermit]
Perhaps because the Devil is always in the details. In this case, the detail is that fluorine salts are nasty (!) and they have to be kept really pure or they can turn into hydrofluoric acid which gets frighteningly close to the alchemists "universal solvent" (which of course could be safely stored only in a solution of supersaturated universal solvent).
We know how to purify the salts required in lab quantities, but not at production quantities and not at an affordable cost.
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[Blunderov] Thanks for that information. I had not heard of Hydrofluoric acid before. Quite impressive stuff as I now discover.
http://en.wikipedia.org/wiki/Hydrofluoric_acid
<snip>Hydrofluoric acid is best known to the public for its ability to dissolve glass by reacting with SiO2 (silicon dioxide), the major component of most glass, to form silicon tetrafluoride gas and hexafluorosilicic acid. This property has been known since the 17th century, even before hydrofluoric acid had been prepared in large quantities by Scheele in 1771...Because of its high reactivity toward glass, hydrofluoric acid must be stored (in small quantities) in polyethylene or Teflon containers. It is also unique in its ability to dissolve many metal and semimetal oxides.</snip>
Hermit, if you have time, could you be kind enough to clarify something for me/us? According to the original blurb which I posted the the claim is made that this Thorium technology presents no proliferation problems. And yet in the piece that Fritz posted it seems as if there are a variety of highly fissile and weapons capable materials produced at different stages of the (various?) cycles.
(I had been hoping that there would have been a solution to the Iranian 'problem' here; that the Iranians could offer to build 'Islamic'(tm) reactors thus pulling the rug right out from under many bellicose feet and scoring some nice points to boot.)
Thanks in anticipation 
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Re:Revolutionary Thorium Reactor
« Reply #4 on: 2009-06-30 13:03:32 » |
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[Blunderov] Hermit, if you have time, could you be kind enough to clarify something for me/us? According to the original blurb which I posted the the claim is made that this Thorium technology presents no proliferation problems. And yet in the piece that Fritz posted it seems as if there are a variety of highly fissile and weapons capable materials produced at different stages of the (various?) cycles.
[Hermit]
I took your question to mean "proliferation of nuclear weapons", because aside from the four non-signatories to the NPT, being the DPRK, India, Israel and Pakistan, who are not legally entitled to assistance from any NPT states, despite American, British, French, German, Israeli, PRC and Russian contraventions of the NPT in assisting these countries, it is recognized that all signature countries have a right to all possible assistance to promote their peaceful application of the nuclear cycle and thus, by definition, not proliferation.
This turned out to be a very complicated question to answer, because understanding the answer really presupposes a comprehension of both nuclear weapons design and the nuclear fuel cycle. I am going to do my best in turning it into bite sized chunks.
To begin with, please read http://www.reference.com/browse/nuclear+device. Pay attention and make notes. There will be a small quiz at the end :-P
It doesn't deal with the use of laser triggered, inertially confined Deuterium/Tritium warheads which are definitely 4th generation devices but which, given the rapid proliferation of femtosecond accurate optical technology for communications purposes, may well end up becoming the route of choice to fast delivery of small, compact, powerful and highly programmable nuclear devices.
Despite this lack, the article identifies many (but by no means all) of the factors surrounding the production of the relatively crude fission/fusion core of the 1st,2nd and 3rd generation nuclear device. It should be noted that a device triggered with a pulse of neutrons from a few grams of Tritium, possibly laser exited, can reduce the amount of Plutonium or Uranium required for an equivalent device by 30% to 70%, while the use of Gold or Cobalt accelerator shells can result in similar reductions for the same degree of particle production. The use of Tritium injection also offers the ability to create relatively simple fail safe selectable power cores.
Of course, aside from simple, low yield and very bulky gun type devices which can only be manufactured using Uranium cores but are relatively trivial to build, all other designs require the ability to build shaped charges to a very high degree of precision, and the ability to synchronize the detonation of multiple shaped charges with a great deal of accuracy. While this is becoming simpler (due to increasing availability of miniaturized timing and optical components), it is unlikely that anyone would rely on any device without prior testing - even when it is built to what is thought to be a "known good" design. This means that, outside of a gun type device, we are likely to have prior warning of the achievement of nuclear capability in the form of a test. And yes, Israel has tested a shell and devices.
You might safely conclude from the above and the referenced site that design, at least theoretically, is really not much of a challenge, but that only a few materials are suited to the construction of a classical nuclear device. These include:- Highly enriched Uranium
- Plutonium
- Tritium
- Lithium Deuteride
- Deuterium
- Gold
- Cobalt
Even though Uranium is a relatively common metal, it is very challenging to enrich it. Highly enriched Uranium is difficult to buy and is carefully tracked. While some low power separation techniques have been developed, they currently require highly advanced technology, meaning that high power enrichment installations are the norm. This made them relatively easy to see from the air until Israel's attack on the civilian Iraqi program persuaded countries to begin building their facilities deep underground. Libya, Iran, Israel, the ROC (Taiwan) and North Korea have all built underground centrifuge cascades although Libya has abandoned its nuclear programs and Iran's is fully inspected.
While Plutonium is usually obtained from spent fuel rods from a conventional reactor (as the DPRK is doing), it can be produced cheaply and in vast quantities in a reactor designed for the purpose, by building a pile in a containment shell lined with a "blanket" of Uranium which when bombarded with neutrons from the pile is converted to Plutonium. South Africa, Pakistan, India, Israel and North Korea have all taken this approach to massively increase the Plutonium available to them.
Similarly, Tritium may be produced and concentrated in a Heavy Water reactor, but the quantities created are small and the concentration process expensive, so Tritium is usually created by replacing some fuel rods in a research reactor with Lithium which will produce Tritium when bombarded.
Like Gold and Cobalt, Deuterium is not radioactive per se (it is a moderator), and as it also has non weapons uses, it is less controlled than the supplies above. Deuterium supplies are obtained through concentration, usually chemical, of natural supplies.
From the above it is possible to conclude that so long as supplies of highly enriched Uranium, Plutonium and Tritium are well managed that the likelihood of (weapons) proliferation is small, and in fact, the key to the control of production of all the above radioactive products is to control access to highly enriched Uranium (HEU). Further, so long as supplies of HEU are controlled and managed by the IAEA the probability of diversion of material, without which no weapons proliferation is possible, is effectively zero. There is a challenge (which will increase in significance) in that Tritium, not releasing ionizing radiation, is not subject to IAEA controls - and in my opinion, it should be, but because it is only produced in reactors using HEU, and all HEU reactors outside of the 4 renegade non-signaturies, the DPRK, India, Israel and Pakistan, are controlled, the problem, and availability, is limited (although I know that at least Russia and Israel sold Tritium as late as the 1990s without requesting export control documents)*.
The ability to create highly enriched Uranium is dependent on:- Knowledge of the possible processes
- Technical competence to implement the required processes
- Energy to operate the required processes
- Production capacity to produce meaningful output streams
- Time to perform the required processes
- Raw material to process.
The higher the concentration of desired isotopes, and just as importantly, the lower the concentration of undesired isotopes, in the raw material, the easier all of the above becomes. This is why, while it is theoretically possible to process fluids from a Thorium salt reactor to extract materials from the stream, it would be crazy, because readily available and cheap Uranium yellowcake is a much more significant source of desirable Uranium isotopes, with far fewer neutron absorbing isotopes to dispose of.
As such, the (weapons) proliferation value of a Thorium reactor is tiny.
Apropos of something, while Uranium is relatively common, there is not enough economically accessible to take us beyond 50 years at current usage levels without using fast breeder reactors to recycle the supply - which poses massive proliferation risks and the large-scale production of nasty long life isotopes - which are very difficult to dispose of safely (I think South Africa is the only country to achieve safe disposal so far). Which is why we are not currently operating any fast breeder reactors and why I think the approach India is described as taking in this article seems sensible. Although India's choices are very likely shaped by the unstated expectation that the Southern Asian breeding rate will lead to nuclear war and the probably faulty idea that the country with the largest arsenal will "win".
[Blunderov] (I had been hoping that there would have been a solution to the Iranian 'problem' here; that the Iranians could offer to build 'Islamic'(tm) reactors thus pulling the rug right out from under many bellicose feet and scoring some nice points to boot.)
[Hermit]
Iran isn't the problem. Israel is a problem. American perceptions of Iraq and Israel are an even bigger problem.
Along with the aforementioned troubles of purifying the salts in a TSR on an industrial basis.
Iran has mastered the Uraniun fuel cycle, and I do not see them abandoning it at this stage. My suspicion is that they are also already in the process of mastering laser separation which will almost certainly survive any attacks.
Anyone attacking them at this point would merely drive them out of the NPT and force them to overcome their ethical objections to nuclear weapons. Ongoing sanctions may well have the same effect. I am hoping that somebody in US intelligence is making this fairly obvious point to the Whitehouse and State Department.
Like everyone else, at this point Iran needs Space Solar.
[Hermit] *And if I were an weapons scientist in a country which had acceded to the NPT, and my political bosses sought a "perfect weapon," I would be focussing on an X-ray laser triggered Tritium-Deuterium/Lithium Deuteride fusion weapon. Despite membership of the NPT it would be perfectly legal to build it (not using any materials producing ionizing radiation), could be much smaller and potentially lighter than existing weapons, and a single device family could be programmed to produce either a variable explosive effect (from a few kilograms to a few megatons) to a pure neutron effect depending on the composition of the outer shell selected. Deploying one may or may not be legal, depending on where and how and against what it was targeted, but as the US and Israel have proved, neither the International Court nor International War Crimes tribunals appear to have effective teeth - and the Nuremberg tribunal created the precedent that one cannot prosecute an enemy for something one does not prosecute when your own troops do it (although of course the US kangaroo court prosecution and execution of Saddam Hussein showed that that won't prevent abuse of process when courts are prepared to participate in war crimes).
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With or without religion, you would have good people doing good things and evil people doing evil things. But for good people to do evil things, that takes religion. - Steven Weinberg, 1999
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Blunderov
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"We think in generalities, we live in details"
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Re:Revolutionary Thorium Reactor
« Reply #5 on: 2009-07-01 19:32:47 » |
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[Blunderov] Many thanks to The Hermit for the clear elucidation of a complicated subject. It would be excellent if a solution could be devised for the hydrofluoric acid problem. Seems worth a serious investment.
Best Regards.
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