India's Thorium based nuclear power programme

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http://www.fissilematerials.org/blog/2010/02/history_and_status_of_fas.html

History and status of fast breeder reactor programs worldwide


The International Panel on Fissile Materials released a new research report, Fast Breeder Reactor Programs: History and Status (a pdf copy of the report is here). The report argues that the track record of all fast breeder reactor programs demonstrates that sodium-cooled reactors cannot serve as a major part of the long-term nuclear waste disposal solution.

The report notes that "fast breeder" reactors already have been the focus of more than $50 billion in development spending, including more than $10 billion each by the U.S., Japan and Russia. Yet, the report further notes, none of these efforts has produced a reactor that is anywhere near economically competitive with light-water reactors ... After six decades and the expenditure of the equivalent of tens of billions of dollars, the promise of breeder reactors remains largely unfulfilled and efforts to commercialize them have been steadily cut back in most countries. The reactors have been plagued by high costs, often multi-year downtime for repairs, multiple safety problems, and unresolved proliferation risks.

REPORT: UNSUCCESSFUL "FAST BREEDER" IS NO SOLUTION FOR LONGTERM REACTOR WASTE DISPOSAL ISSUES

After Over $50 Billion Spent by US, Japan, Russia, UK, India and France, No Commercial Model Found; High Cost, Unreliability, Major Safety Problems and Proliferation Risks All Seen as Major Barriers to Use.


PRINCETON, N.J. - February 17, 2010 - Hopes that the "fast breeder"- a plutonium-fueled nuclear reactor designed to produce more fuel than it consumed -- might serve as a major part of the long-term nuclear waste disposal solution are not merited by the dismal track record to date of such sodium-cooled reactors in France, India, Japan, the Soviet Union/Russia, the United Kingdom and the United States, according to a major new study from the International Panel on Fissile Materials (IPFM).

Titled "Fast Breeder Reactor Programs: History and Status," the IPFM report concludes: "The problems (with fast breeder reactors) ... make it hard to dispute Admiral Hyman Rickover's summation in 1956, based on his experience with a sodium-cooled reactor developed to power an early U.S. nuclear submarine, that such reactors are 'expensive to build, complex to operate, susceptible to prolonged shutdown as a result of even minor malfunctions, and difficult and time-consuming to repair.'"

Plagued by high costs, often multi-year downtime for repairs (including a 15-year reactor restart delay in Japan), multiple safety problems (among them often catastrophic sodium fires triggered simply by contact with oxygen), and unresolved proliferation risks, "fast breeder" reactors already have been the focus of more than $50 billion in development spending, including more than $10 billion each by the U.S., Japan and Russia. As the IPFM report notes: "Yet none of these efforts has produced a reactor that is anywhere near economically competitive with light-water reactors ... After six decades and the expenditure of the equivalent of tens of billions of dollars, the promise of breeder reactors remains largely unfulfilled and efforts to commercialize them have been steadily cut back in most countries."

The new IPFM report is a timely and important addition to the understanding about reactor technology. Today, with increased attention being paid both to so-called "Generation IV" reactors, some of which are based on the fast reactor technology, and a new Obama Administration panel focusing on reprocessing and other waste issues, interest in some quarters has shifted back to fast reactors as a possible means by which to bypass concerns about the longterm storage of nuclear waste.

Frank von Hippel, Ph.D., co-chair of the International Panel on Fissile Materials, and professor of Public and International Affairs, Woodrow Wilson School, Princeton University, said: "The breeder reactor dream is not dead but it has receded far into the future. In the 1970s, breeder advocates were predicting that the world would have thousands of breeder reactors operating by now. Today, they are predicting commercialization by approximately 2050. In the meantime, the world has to deal with the legacy of the dream; approximately 250 tons of separated weapon-usable plutonium and ongoing -- although, in most cases struggling -- reprocessing programs in France, India, Japan, Russia and the United Kingdom."

Mycle Schneider, Paris, international consultant on energy and nuclear policy, said: "France built with Superphenix, the only commercial-size plutonium fueled breeder reactor in nuclear history. After an endless series of very costly technical, legal and safety problems it was shut down in 1998 with one of the worst operating records in nuclear history."

Thomas B. Cochran, nuclear physicist and senior scientist in the Nuclear Program at the Natural Resources Defense Council, said: "Fast reactor development programs failed in the: 1) United States; 2) France; 3) United Kingdom; 4) Germany; 5) Japan; 6) Italy; 7) Soviet Union/Russia 8) U.S. Navy and 9) the Soviet Navy. The program in India is showing no signs of success and the program in China is only at a very early stage of development. Despite the fact that fast breeder development began in 1944, now some 65 year later, of the 438 operational nuclear power reactors worldwide, only one of these, the BN-600 in Russia, is a commercial-size fast reactor and it hardly qualifies as a successful breeder. The Soviet Union/Russia never closed the fuel cycle and has yet to fuel BN-600 with plutonium."

M.V. Ramana, Ph.D., visiting research scholar, Woodrow Wilson School and the Program in Science, Technology, and Environmental Policy, Princeton University, said: "Along with Russia, India is one of only two countries that are currently constructing commercial scale breeder reactors. Both the history of the program and the economic and safety features of the reactor suggest, however, that the program will not fulfill the promises with which it was begun and is being pursued. Breeder reactors have always underpinned the DAE's claims about generating large quantities of cheap electricity necessary for development. Today, more than five decades after those plans were announced, that promise is yet to be fulfilled. As elsewhere, breeder reactors are likely to be unsafe and costly, and their contribution to overall electricity generation will be modest at best."

OTHER KEY FINDINGS

The IPFM report also found:

* The rationale for breeder reactors is no longer sound. "The rationale for pursuing breeder reactors -- sometimes explicit and sometimes implicit -- was based on the following key assumptions: 1. Uranium is scarce and high-grade deposits would quickly become depleted if fission power were deployed on a large scale; 2. Breeder reactors would quickly become economically competitive with the light-water reactors that dominate nuclear power today; 3. Breeder reactors could be as safe and reliable as light-water reactors; and, 4. The proliferation risks posed by breeders and their 'closed' fuel cycle, in which plutonium would be recycled, could be managed. Each of these assumptions has proven to be wrong."

* Significant safety issues are unresolved. "Sodium's major disadvantage is that it reacts violently with water and burns if exposed to air. The steam generators, in which moltensodium and high-pressure water are separated by thin metal, have proved to be one of the most troublesome features of breeder reactors. Any leak results in a reaction that can rupture the tubes and lead to a major sodium-water fire. .... a large fraction of the liquid-sodiumcooled reactors that have been built have been shut down for long periods by sodium fires. Russia's BN-350 had a huge sodium fire. The follow-on BN-600 reactor was designed with its steam generators in separate bunkers to contain sodium-water fires and with an extra steam generator so a fire-damaged steam generator can be repaired while the reactor continues to operate using the extra steam generator. Between 1980 and 1997, the BN-600 had 27 sodium leaks, 14 of which resulted in sodium fires ... Leaks from pipes into the air have also resulted in serious fires. In 1995, Japan's prototype fast reactor, Monju, experienced a major sodium-air fire. Restart has been repeatedly delayed, and, as of the end of 2009, the reactor was still shut down. France's Rapsodie, Phenix and Superphenix breeder reactors and the UK's Dounreay Fast Reactor (DFR) and Prototype Fast Reactor (PFR) all suffered significant sodium leaks, some of which resulted in serious fires."

* Downtime makes the breeder reactor unreliable. "... a large fraction of sodium-cooled demonstration reactors have been shut down most of the time that they should have been generating electric power. A significant part of the problem has been the difficulty of maintaining and repairing the reactor hardware that is immersed in sodium. The requirement to keep air from coming into contact with sodium makes refueling and repairs inside the reactor vessel more complicated and lengthy than for water-cooled reactors. During repairs, the fuel has to be removed, the sodium drained and the entire system flushed carefully to remove residual sodium without causing an explosion. Such preparations can take months or years.

* Proliferation risks have not been addressed. "All reactors produce plutonium in their fuel but breeder reactors require plutonium recycle, the separation of plutonium from the ferociously radioactive fission products in the spent fuel. This makes the plutonium more accessible to would-be nuclear-weapon makers. Breeder reactors -- and separation of plutonium from the spent fuel of ordinary reactors to provide startup fuel for breeder reactors -- therefore create proliferation problems. This fact became dramatically clear in 1974, when India used the first plutonium separated for its breeder reactor program to make a 'peaceful nuclear explosion.' Breeders themselves have also been used to produce plutonium for weapons. France used its Phenix breeder reactor to make weapon-grade plutonium in its blanket. India, by refusing to place its breeder reactors under international safeguards as part of the U.S.-India nuclear deal, has raised concerns that it might do the same."

* Most breeder reactors are being shut down. "Germany, the United Kingdom and the United States have abandoned their breeder reactor development programs. Despite the arguments by France's nuclear conglomerate Areva, that fast-neutron reactors will ultimately fission all the plutonium building up in France's light-water reactor spent fuel, France's only operating fast-neutron reactor, Phenix, was disconnected from the grid in March 2009 and scheduled for permanent shutdown by the end of that year. The Superphenix, the world's first commercial-sized breeder reactor, was abandoned in 1998 and is being decommissioned. There is no follow-on breeder reactor planned in France for at least a decade." For the full text of the IPFM study, go to http://www.fissilematerials.org on the Web.

ABOUT THE IPFM

The International Panel on Fissile Materials (IPFM) was founded in January 2006. It is an independent group of arms-control and nonproliferation experts from 17 countries, including both nuclear weapon and non-nuclear weapon states. The mission of the IPFM is to analyze the technical basis for practical and achievable policy initiatives to secure, consolidate, and reduce stockpiles of highly enriched uranium and plutonium. These fissile materials are the key ingredients in nuclear weapons, and their control is critical to nuclear disarmament, halting the proliferation of nuclear weapons, and ensuring that terrorists do not acquire nuclear weapons. The IPFM is co-chaired by Professor R. Rajaraman of Jawaharlal Nehru University in New Delhi and Professor Frank von Hippel of Princeton University. Its members include nuclear experts from Brazil, China, France, Germany, India, Ireland, Japan, South Korea, Mexico, the Netherlands, Norway, Pakistan, Russia, South Africa, Sweden, the United Kingdom and the United States. Princeton University's Program on Science and Global Security provides administrative and research support for the IPFM. IPFM's initial support is provided by a fiveyear grant to Princeton University from the John D. and Catherine T. MacArthur Foundation of Chicago.

CONTACT: Ailis Aaron Wolf, + 1 (703) 276-3265 or [email protected].

EDITOR'S NOTE: A streaming audio recording of IPFM's news event will be available on the Web as of 5 p.m. EST/2200 GMT on February 17, 2010 at http://www.fissilematerials.org.
 
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http://www.hindu.com/2010/05/14/stories/2010051459652400.htm


Prototype Fast Breeder Reactor crosses milestone


Chennai: As a very tall crane ever so slowly winched up the circular contraption weighing 78 tonnes with "a spider" gripping it from top on Thursday, the contraption called thermal baffle sometimes stayed still in midair. At times, it swayed slowly as it rose in the air and hundreds of eyes were riveted on it. "Roger," "roger" went the commands on walkie-talkies to those manning the crane. As the thermal baffle reached a height of about 80 metres, it was gingerly lowered to a height of 54 metres from the ground and then placed deftly inside the main vessel of the Prototype Fast Breeder Reactor (PFBR) under construction at Kalpakkam, near Chennai.

Applause rang out as the baffle fitted flush inside the main vessel, with just 90 mm of space separating the two contraptions. With that, the tension that had gripped the engineers of Bharatiya Nabhikiya Vidyut Nigam Limited (BHAVINI), which is building the PFBR, was gone. The entire operation took about an hour.

Prabhat Kumar, Project Director, BHAVINI, who was happy that the PFBR project had flawlessly crossed the milestone, said "the entire world was looking at India" building the 500 MWe PFBR. Its construction signalled the beginning of the second stage of India's nuclear power programme, under which a series of fast breeder reactors would be built.

The PFBR will use plutonium-uranium oxide as fuel and liquid sodium as coolant. It will go critical in March 2012.

All the internals of the reactor including the core and the primary sodium circuit are contained in a single main vessel.

The thermal baffle, with two concentric shells, is about 12.5 metres in diameter and five metres tall. Although the baffle itself weighs 78 tonnes, the total weight handled for its erection was 170 tonnes.

Under the first stage of the Department of Atomic Energy's nuclear power programme, a series of Pressurised Heavy Water Reactors, using natural uranium as fuel and heavy water as both coolant and moderator, has already been built.

Mr. Prabhat Kumar said the baffle would provide passage for the cold sodium to cool the main vessel and bring down the temperature during the normal operation of the reactor from 550 deg. Celsius to 450 deg. Celsius. This was to minimise the effect of creep, thermal fatigue and embrittlement of the structure. The baffle was fabricated at the site by Bharat Heavy Electricals Limited and will be integrated to the main vessel by in situ welding.

P. Chellapandi, Director, Nuclear Group, Indira Gandhi Centre for Atomic Research (IGCAR), said the winching up of the baffle employed a "floating spider concept."

Requires careful planning

The handling of its two concentric shells required careful planning and development of procedures. Conventional methods would not do. "We adopted an innovative method wherein the shape of the thermal baffle was maintained to a high degree of accuracy and there was no fear of collapsing of the structure due to buckling," Mr. Chellapandi said. It was the IGCAR which designed the PFBR, he added.

S.C. Chetal, Director, Reactor Engineering Group, IGCAR, said the PFBR would have a life of 40 years.

"We have been able to demonstrate to the country that we can build this reactor with high standards of safety," he said.
 
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http://www.newkerala.com/news/fullnews-92504.html

India open to more exports of heavy water: Official

Bangalore, Apr 19 : India, which is a surplus nation production of heavy water
, was open for more exports subject to government approvals, Heavy Water Board Chief Executive and Chairman A L N Rao said today.

Delivering IISc Diamond Jubilee Commemoration Lecture here, he said the Board had exported heavy water to firms in the US, South Korea and China. However, exports to neighbouring countries had stopped after the first shipment of 30 tonnes, he said.

''Presently India is the largest producer of heavy water in the world and is the only country using multiple technologies for production.

''India possesses moderate 61,000 tonne reserve of uranium and 2.25 lakh tone of thorium. This, however, increases manyfold the country's potential of augmenting nuclear power capacity,'' he said.

He said HWB presently operates five industrial scale heavy water plants located in different parts of the country. The setting up of Managuru plant on the banks of Godavari had made the country heavy water surplus, he said.
 
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http://www.livemint.com/2009/09/08215934/Does-India-really-need-the-Hb.html

Does India really need the H-bomb?


The recent assertion by K. Santhanam, formerly with the Defence Research and Development Organisation and a key figure who coordinated the Shakti series of nuclear tests, that the thermonuclear bomb tested on 11 May 1998 was a fizzle and failed to reach the desired yield has raised questions about the reliability of India's nuclear arsenal.

It has also renewed the debate on whether it is essential to conduct further nuclear tests or not to ensure India's thermonuclear weapon will work as expected.

It is the wrong question to ask. The real question is: does India really need a thermonuclear weapon to ensure its credible minimum nuclear deterrent?

Before addressing this question, it is important to understand what a thermo- nuclear weapon is and how it is different from a nuclear weapon. It is equally crucial to understand the factors motivating countries to acquire such weapons.

So, what is a thermo- nuclear bomb? A nuclear bomb, which is triggered by conventional explosives to create a chain reaction from the critical mass of fissile material, derives its explosive power by splitting (fissioning) atoms of the heavy elements uranium (U235) and plutonium (Pu239). That is why a nuclear bomb is known as a fission weapon.

In contrast, a thermonuclear bomb is also called a fusion bomb or a hydrogen bomb because the bomb derives its explosive power from fusing atoms of the light element hydrogen, such as tritium (3H) or deuterium (2H or D). Since fusion can only be achieved at extremely high temperatures of around 10,000 degrees Celsius (such as those found in the sun), hydrogen bombs are triggered by a fission bomb, which is the only source capable of producing these high temperatures on earth. Because of the high temperatures needed for fusion, the hydrogen bomb, or H-bomb, is also known as a thermonuclear bomb.

The H-bomb is a two-stage weapon where a fission nuclear bomb serves as the primary detonator, which then compresses and triggers a fusion fuel secondary, leading to a massive explosion. In theory, an H-bomb can produce unlimited destructive power. The biggest bomb tested by the Soviet Union produced 50 megaton of explosive power—nearly 3,000 times more destructive power than the bomb dropped on Hiroshima.

The H-bomb is also the most complex of all nuclear weapons to develop and this is why no country has been able to perfect it in a single shot. It would have been a miracle or a technological fluke if the first ever test of an Indian H-bomb had worked flawlessly.

The challenges of building an H-bomb notwithstanding, there are at least three reasons why countries seek to acquire this deadliest of all nuclear weapons. First, thermonuclear weapons provide more bang for the buck in that the fissile material used to make a fission bomb can be made a hundred or thousand times more lethal by adding a secondary or a second-stage fusion at little extra cost.

This might be particularly appealing to countries that have limited fissile material and feel the need to develop weapons with yield in the megatons. Although this might be attractive to a country such as India that perhaps has limited fissile material for all its strategic nuclear needs, it is a huge gamble to depend on a design that has not worked as expected. It would be far more prudent to use the material in a boosted weapon, which has already been successfully tested in 1998.

Secondly, countries that adhere to a counter-force strategy, which seeks to attack and destroy the nuclear forces and related command and control capabilities of the other side in a decapitating first strike before these forces can be launched, will find the H-bomb attractive. The enormous destructive power of the H-bomb is particularly suitable for destroying the hardened underground nuclear missile silos and command and control centres.

However, for India, which has a declared no-first-use strategy and an implied second-strike, counter-city strategy (which calls for India to absorb the first nuclear strike and then retaliate against the vulnerable cities of the other side), the H-bomb is not particularly useful. Such massive destructive power is not necessary against unprotected cities, which are particularly vulnerable even to fission weapons.

Perhaps this is why the Indian Armed Forces, which have consistently asked for nuclear weapons, have never demanded the H-bomb. The outgoing navy chief and the chairman of the chiefs of staff committee, Admiral Sureesh Mehta, endorsed this when he categorically stated that India had already acquired a credible minimum nuclear deterrent, implying that an H-bomb was not essential for India's strategic nuclear objectives.

The third reason why countries might seek the H-bomb is prestige. In fact, given the complexity of building the H-bomb, the history of this bomb is rife with stories about scientists and countries seeking this weapon to prove that they are as good, if not better, than scientists in other countries or even in their own nuclear establishments.

This debate is likely to remain alive and the reliability of India's nuclear arsenal will be constantly questioned until the government firmly endorses the credibility of the arsenal by ruling out any further tests once and for all.

The best way for the Manmohan Singh government to end this debate and shut off the possibilities of future tests is to sign and ratify the comprehensive test ban treaty. Such a move would be even more courageous than signing the Indo-US nuclear deal or, indeed, carrying out more tests for a weapon that India does not really need. Will Singh show this courage of conviction?
 
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India can build upto 200 kilton bomb: Kakodkar

Last updated on: September 24, 2009 12:49 IST

Rubbishing doubts on the efficacy of the hydrogen bomb test in 1998, Atomic Energy Commission Chairman Anil Kakodkar on Thursday said scientists have achieved success in building deterrence capability of up to 200 kiltons.

"Once again I would like to re-emphasise that the 1998 nuclear tests were fully successful. We had achieved all the objectives in toto. It has given us the capability to build deterrence based on both fission and thermonuclear weapon systems from modest to all the way upto 200 kilotons," he said addressing a press conference in Mumbai

Kakodkar, who was Director of the Bhabha Atomic Research Centre in 1998, termed as "unnecessary" the controversy over the Pokhran-II nuclear tests triggered after claims by a former DRDO scientist that the hydrogen bomb experiment was a failure.

R Chidambaram, Chairman of the AEC in 1998 and the current Principal Scientific Adviser to the Union Government, made a presentation on the results of the Pokhran-II nuclear tests.

Former DRDO scientist K Santhanam, who was the DRDO coordinator for the 1998 tests, had claimed that the thermonuclear test was much below expectation triggering a controversy.

Santhanam had also demanded an inquiry by an independent panel of experts into the test results.
 
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http://nuclearstreet.com/blogs/nucl...ech-Leader-In-Fast-Breeder-Reactors-1852.aspx

Dr Anil Kakodkar: India Could Be Global Tech Leader In Fast Breeder Reactors




Small sized Pressurized Heavy Water Reactors (PHWRs), which this country is capable of building, have considerable demand in developing nations

- By Abby Gessner -

Dr. Anil Kakodkar, Chairman, Atomic Energy Commission (AEC) and Secretary, Department of Atomic Energy (DAE), contends that India's capability to independently design and build thorium-based Fast Breeder Reactors (FBRs) will make the country a global technological leader in this crucial area in the future.

In an interview to www.asiannuclearenergy.com, he said that small sized Pressurized Heavy Water Reactors (PHWRs), which this country is capable of building, have considerable demand in developing nations.

The interview, which also appears in the forthcoming issue of Asian Nuclear Energy, a bi-monthly and first of its kind to power nuclear commerce, and published by New Media, India's largest bilateral trade magazine publishing house, stresses the importance of private sector participation in making this country a global hub for nuclear component industry.

A key negotiator of the historic Indo-US civilian nuclear energy agreement, culminating in the lifting of the 34-year-long ban on India by the Nuclear Suppliers' Group, Dr. Kakodkar said, "The Immediate benefit of the international civil nuclear commerce with other countries will be an additionality of installed nuclear power capacity (40,000 MWe by 2020) over and above that to be achieved through the indigenous three-stage programme."

India's three-stage nuclear energy programme comprises building uranium-fuelled Pressurized Heavy Water Reactors (PHWRs), development of Fast Breeder Reactor (FBRs) and an advanced nuclear power system based on Thorium-Uranium-fuelled reactors.

Kakodkar said, "With nuclear energy likely to become centre stage, FBRs are expected to be in considerable demand in future. With India having taken the lead in this crucial area, we could very well be the technological leaders worldwide."

He said the same thing could happen in the context of thorium systems a little later. "Thorium based reactor technology forms the third stage of the three-stage Indian Nuclear Power Programme. It is envisaged that reactors based on thorium will become commercial not only for electricity generation but also for providing high temperature process heat for industries and hydrogen as a clean fuel as substitute for the petroleum based fuels," Dr. Kakodkar added.

Taking into consideration the vast thorium resources in the country, it will provide energy for several centuries," he said.

"On a short-term basis the small size Pressurized Heavy Water Reactors (PHWRs) have a potential to be supplied to some developing countries, Kakodkar said.

On scaling up of India's installed nuclear power generation capacity by nearly five times to 20,000 MWe by 2020 from the present 4,120 MWe, Dr. Kakodkar said that this target "is likely to be revised upwards."

About the funds required for meeting the 20,000 MWe target, he said, the state-owned Nuclear Power Corporation of India Ltd (NPCIL) could manage about 10,000 MWe through its own financial resources. Atomic Energy Act in its current form does allow investment by private sector up to the extent of 49 percent, Dr. Kakodkar added.

While the Atomic Energy Act stipulates that nuclear power generation to be done by a government company, holding at least 51 percent equity, the private sector could, however, carry out manufacturing of nuclear equipment and other supply chain activities including construction, Dr. Kakodkar said.

He stressed that Indian companies must maintain their technological competence and ability to tap emerging markets. "In so doing they should not allow themselves to be subjected to extraterritorial application of foreign laws that restrict their participation in the domestic development of India's three-stage nuclear power programme which is the key to opening up of very large potential of nuclear power," Dr. Kakodkar cautioned.

DAE would continue its engagement with the Indian industry in this regard, he added.
 
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http://www.hindustantimes.com/Lab-a...eactor-New-BARC-director/Article1-545969.aspx

Lab at Tarapur to test heavy water reactor: New BARC director

By December, the Bhabha Atomic Research Centre will set up a research laboratory at Tarapur to test various systems of the 300 mega watt Advanced Heavy Water Reactor (AHWR), which will allow India to use thorium instead of uranium for power generation.

The trials for the AHWR will begin in 2011, said Ratan Kumar Sinha, the new director of BARC who took charge on Wednesday.

Appointed as the tenth director, Sinha who has been guiding the design and development of AHWR said: "The reactor has been recognised as a world class international design. It has undergone peer review and every licensing procedure has been carried out."

Sinha (59) added that IIT-Bombay and IIT-Kharagpur have been simulating AHWR parts and supplying data to BARC.

While regulatory requirements to set up the AHWR have come through, search is on for a site. "For such a small power project, a dedicated site is not economically viable. We will need to deal with it," said Sinha. "In a couple of weeks, we will start issuing tenders for design and preparation on non-nuclear systems for AHWR."

Apart from deployment of thorium on a commercial scale, Sinha said some of the centre's priorities will be to ensure fuel supply to the country's first prototype fast breeder reactor and other non-safeguarded reactors, deployment of power and increase in production and supply of radio isotopes at a competitive price.

The former director, Reactor Design & Development Group & Design, Manufacturing & Automation Group, said that while the objectives have been set by his predecessors, he will try and get them achieved faster. "Priorities will not change. The goals are there. The milestones have to be reconfigured," he said.

"The new unit will generate three times more power which assess whether various systems in the AHWR can withstand high pressure levels. It will have four channels and the fuel handling machine in one of them will be tested," said outgoing director S. Banerjee.
 
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http://www.world-nuclear-news.org/E...cts_proposed_Indian_uranium_mine-1705105.html

Rejection of proposed Indian uranium mine


Plans to develop a uranium deposit within the Balphakran National Park in Meghalaya state, India, have been rejected by a federal ministry because local authorities had failed to prevent illegal coal mining in the area.

The Department of Atomic Energy (DAE) had sought approval from the Ministry of Environment and Forests to conduct exploratory drilling for uranium in the Garo Hill District. However, at a recent meeting of its Standing Committee of the National Board on Wildlife, the ministry decided to reject the proposal.

In a statement, the committee said that, while acknowledging India's urgent need to augment domestic uranium supplies, it "took this decision keeping in view of the sentiments of the local people and a number of representations received from local civil society groups."

During its meeting, the committee was presented with a report by one of its members - Asad Rahmani of the Bombay Natural History Society - on illegal private coal mining around the Balphakran National Park. Having visited the area, he found that there were private coal mines operating in Meghalaya state, close to the Bangladesh border, in violation of national environmental and mining regulations.

In his report, Rahmani said, "The Chief Executive Council of Garo Hills Autonomous District Council has all the powers to stop these illegal mines. Similarly, the District Magistrate of Baghmara can also take action to stop illegal mines. However, in effect neither of these agencies appears to have any control on the ground situation." He added, "After visiting the area, I found that it gives the appearance of an untamed wild frontier where anyone can occupy the land and loot the natural resources."

Rahmani noted, "The most shocking fact was that all this illegally extracted coal is being exported 'legally' to Bangladesh through a border outpost at Gasaupara." He added, "Interestingly, the office of the Department of Mines and Minerals in located at Gasaupara. The whole area around Gasaupara village is spoiled due to coal dumps (on any open space), movement of trucks, pollution of water bodies, noise, and black exhaust by rickety old trucks."

The Standing Committee subsequently decided to press the state government of Meghalaya to implement the recommendations contained within the report. These included the immediate ban on all mining and road construction activity within the Balphakran National Park and to introduce strict regulation of all coal mines in Garo Hills and other parts of the state. It also called for the implementation of "proper mining plans which will ensure that local people avail the greatest benefit from mining."

There are currently 19 nuclear power reactors in commercial operation in India, with a combined generating capacity of 4183 MW. The country expects to have 20,000 MWe of nuclear capacity online by 2020 and 63,000 MWe by 2032. However, India's uranium resources are modest with 54,000 tonnes as reasonably assured resources and 23,500 tonnes as estimated additional resources in situ. Accordingly, from 2009 India is expecting to import an increasing proportion of its uranium fuel needs.

Mining and processing of uranium is carried out by Uranium Corporation of India Ltd, a subsidiary of the DAE, at Jaduguda, Bhatin, Narwapahar and Turamdih - all in Jharkhand state near Calcutta. A common mill is located near Jaduguda that processes some 2090 tonnes of ore per day.
 
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http://nucleargreen.blogspot.com/2010/04/indian-light-water-reactor-costs.html

Indian Light Water Reactor Costs




Business Daily of THE HINDU group of publications in a recent article, titled $1600/kW is benchmark cost for light water reactor imports sheds new light on Indian present and future LWR costs and plans. The article that the two Russian VVER-1000 reactors nearing completion at Koodankulam have a
total construction cost was estimated at $2.6 billion.

At current exchange rates, it translates to around Rs 6.5 crore per MW.

The Russian Government had provided India with long-term credit, which covers almost half of the cost of the first two units.
Indian sources rarely provide much information on financing or credit costs for nuclear capital financing. I suspect that the other 50% for the Koodankulam reactors come directly or indirectly from the Indian government. According to the story,
NPCIL expects the first Koodankulam unit, when operational, to be able to sell power at less than Rs 2.50 a unit (kilowatt hour).
When completed, the two VVER-1000 will increase Indian rated nuclear capacity by 50%. Most locally designed Indian reactors are small and have a rated power output of about 1/5th that of the Russian designed WWERs. Reactor manufactures often see reactor sales as loss leaders, and plan to recoup discounts by long term contracts for nuclear fuel. This fits in well with long term Indian nuclear plans. The Indians intend to use the "spent nuclear fuel" often wrongly called "nuclear waste," to fuel their future fast breeder reactors. The prototype Indian Fast Breeder reactor is expected to come on line next year, and the Indians plan to build 4 more by 2020. By 2050, the Indians would like to have more than 300 fast breeders online. Thus the Russian interest in selling uranium motivates their willingness to sell the Indians reactors on favorable terms, while the Indian desire to recycle used nuclear fuel in fast reactors, motivates their desire to obtain Russian uranium.
Russia has offered a sweetener in the form of a 30 per cent discount on the $2-billion price tag for each of its new nuclear reactors under discussions for sale to India. The Russians have offered the discount based on plans to start serial production of reactors for the Indian nuclear industry, with much of the equipment and components proposed to be manufactured in India, thereby bringing down costs.

After factoring in the discount, the cost of construction for a mega watt (MW) for each new reactor comes to roughly Rs 7 crore (at current exchange rates, without including decommissioning costs).
The Indians appear to be making the Russian deal the standard for negotiating costs with other reactor manufacturers. Indian industries have announced plans for the construction of $50 billion in industrial infrastructure.
The costing aspect gains significance as the Government's plans to scale up India's nuclear capacity nearly ten-fold over the next decade is underway, with the Centre according 'in principle' approval to over 38,000 MWe (mega watt electrical) of new reactor capacity.

Imported LWR units ranging from 1,000 MWe to 1,650 MWe from Russia, France and the US would make for over 80 per cent of the envisaged capacity, with indigenous Pressurised Heavy Water Reactors of 700 MWe accounting for the rest.
The Indian preference for foreign LWRs, does not reflect negatively on the local nuclear technology. Rather the Indians are interested in access to the uranium that is part of the Light Water Reactor business plan.

The planned new Russian reactor will be a slightly larger version of the Russian WWER-1000s now under construction in India.
 
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http://www.markthetruth.com/defence-a-military/118-quest-for-a-hydrogen-bomb.html

Quest for a Hydrogen Bomb

Indian media is, currently, in throes of a debate about `success' of India's Pokhran_II nuclear tests. The controversy was sparked by scientist, K. Santhanam's disclosure that the tests had questionable success. The whistle-blower, though a bit tardy, particularly denuded the claim that `the tests included a thermo-nuclear device that was 100 per cent successful'.

He claimed that the yield from the thermonuclear device (H-bomb) was a `fizzle' (50-60%), 'short of 100% parameters'. His claim was supported by another scientist, P K Iyengar. Since it was he who had coordinated the Pokhran-II tests, so his statement could not be brushed off as a mere figment of imagination.

The disclosure followed a flurry of statements from Indian prime minister downwards. The Indian prime minister pilloried him for having engendered a needless controversy. Former Indian-army chief General V. P. Malik (retd.) was so piqued that he prompted Dr `Rajgopal Chidambaram and his whole team' to come forward to rebut the claim (IANS, September 6, 2009). He reminded the community of scientists that it was their responsibility to reassure, not confuse the military, about the country's nuclear capability.

R Chidambaram later described Santhanam's claim as `absurd'. Former Indian president A P J Abdul Kalam also refuted the statement of his former colleague. He described the tests as `successful'. He was scientific advisor to the defence ministry when the tests took place.

It stands established now that one of the Pokhran_II-tested bombs was a 60-kiloton H-bomb as confirmed by data released by 125 seismic stations across the world. 'In [Indian] parliament, the government recently described as "erroneous" the conclusions that the Pokhran tests did not comprise a hydrogen bomb' ("So, it was an H-bomb after all", <www. rediff.com/news/1998/jul/27bomb.htm>).

Aside from success or failure of the thermonuclear device, the bitter reality is that India is no longer on peaceful nuclear course. India did make the A- or H-bombs and tested them at Pokhran. India did so despite the fact that the Indian parliament, as desired by the then prime minister Lal Bahadur Shastri, had turned down Jana-Singh-introduced 'resolution for India to develop and deploy Atomic weapons'.

To make the bombs, India misused the Canadian CIRUS reactor as also heavy water imported from the USA .Canada could not supply heavy-water to India as its heavy-water industry was, then, in a nascent stage ( Brahma Chellaney, Nuclear Proliferation: The US-Indian Conflict, Orient-Longman, Hyderabad, "Purchase of American Heavy Water", pp. 5-6).

As of now, India is no longer deficient in its heavy-water needs. In fact, it now exports heavy water to several countries. Consignments of heavy water, contracted by US firm Spectra Gases, New Jersey were shipped from India's Mumbai port. Acording to media reports, A L N Rao, Chief Executive of India's Heavy-Water Board confirmed delivery of consignments to the USA.

India boasts of its heavy water of being 'of excellent quality and the highest purity level'. India is the world's second largest heavy water producer. It has exported 100 tonnes of heavy water to South Korea and 30 tonnes to China. Be it noted that India joined the heavy-water export club in 1996 two years before nuclear weapons test in May 1998.

India has acquired breakthrough ability to extract tritium from heavy water (detritiation) and use it in making H-bombs. India owes this capability to research carried out at a Bhabha Atomic Research Centre (BARC) plant at Kalpakkam (near Madras, Tamil Nadu).

India's ability came to world's notice when the book titled Heavy Water: Properties, Production and Analysis was published by two BARC scientists Sharad M Dave and Himangshu K Sadhu Khan with Mexican co-author Octavio A Novaro. India's technological breakthrough has enabled it to produce tritium isotope through the accelerator process. Details of the detritiation process are given on page 461 of the afore-quoted book.

Janes Intelligence Review, 1998 contains the observation that the pilot plant (under Bhabha Atomic Research Centre, Bombay) has developed a wet-proof catalyst for LPCE (liquid-phase catalytic exchange) employed for 90 per-cent tritium-removal from heavy water. Janes' observes that 'This facility seems to be the only operating LPCE-based detritiation facility in the world. The recovered tritium is being stockpiled for strategic purposes.

Each thermonuclear warhead is said to contain 4 g of the isotope. However, neutron bombs designed to release more radiation will require 10-30 g of tritium'. India's planned three-stage use of power reactors involves use of natural uranium, plutonium and thorium (India has the world's largest reserves of thorium.

Besides exporting heavy water, 'India has stepped up its diplomacy with the Nuclear Suppliers' Group (NSG) countries to become supplier of low-cost nuclear reactors to other countries by joining the NSG' ("India planning to sell low-cost nuclear reactors", The Times of India March 4, 2007).

Who knows how many H - or N-bombs India has made. It also remains to be seen whether India's exports of heavy water and reactors promote peace or war.

The debate in India should be an eye-opener for its slumbering neighbours. India has previously misued the imported reactors and fuel. Will it not misuse the fuel imports facilitated under 123 Agreement (Human Resource Bill 5682 or Henry-Hyde Act)? It is clear that India's nuclear programme is not oriented towards `peaceful purposes'. The debate appears to be government's sponsored. Its underlying purpose is to build consensus for more tests and to strengthen India's opposition to signing the CTBT.
 

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^^^^^^^^^^^^^^^^^

That whole controversy was created , to stir up debate of the Indo-US nuclear agreement.
It was a waste of time.

Now that the deal has been signed and done.

everyone shut up and went on with their lives.
 
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^^^^^^^^^^^^^^^^^

That whole controversy was created , to stir up debate of the Indo-US nuclear agreement.
It was a waste of time.

Now that the deal has been signed and done.

everyone shut up and went on with their lives.
The article made no sense because India was not looking to acquire heavy water but uranium to fuel the reactors. The nuclear deal has little impact on India's heavy water program, other than the NSG clearance allowing India to export heavy water.
 
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http://mjoshi.blogspot.com/2009/09/h-bomb-failure-demands-that-we-re-write.html


H-bomb failure demands that we re-write our nuclear strategy and doctrine





Facts have consequences, especially facts that are inconvenient. The fact that India's hydrogen bomb failed in its first and only test is one such truth. It has consequences for the country's nuclear doctrine, force posture as well as foreign policy issues relating to the US and China, and our approach to the comprehensive test ban treaty and the fissile material cut off treaty.In such circumstances what was considered true in the past must be discarded and new choices must be made. Take the most important one. Should India resume nuclear testing? There will be some who argue that the logic of the situation demands just that. I, for one, am agnostic. India is not a bold country. Our conduct during the 1998 nuclear tests itself suggests that.Having broken the informal embargo on nuclear tests, we rushed in indecent haste to reassure the world of the goodness of our heart. This took two forms — first the offer of the pledge of no first use and a defensive nuclear doctrine. The second, the commitment to a unilateral moratorium. Both were made hurriedly and did not benefit from a wider debate in the government or the country.

Testing


2009 is not the same as 1998. The most important difference is the relative power of China and the US. The last time around, a quick genuflection to the US, prevented the wrath of Beijing. Recall, that in the wake of the tests, the UN Security Council had passed Resolution 1172 which demanded, among other things, that "India and Pakistan immediately stop their nuclear weapon development programmes, refrain from weaponisation or from the deployment of nuclear weapons, cease development of ballistic missiles capable of delivering nuclear weapons and any further production of fissile material for nuclear weapons."Even as late as 2000, China was pressing the world community to act on this resolution. It was only when it became clear that Washington was using the Indian dissonance with China to build bridges with New Delhi, that Beijing changed tack.

In the present circumstances, renewed testing by India could be hazardous to our health. Things are not likely to play out as they did the last time.Fresh tests would terminate the Indo-US nuclear deal because the Hyde Act that enabled it only provides for a waiver for Indian nuclear tests till May 13, 1998. It would also pit India against the international system which is now readying itself to ratify the Comprehensive Test Ban Treaty and the Fissile Material Cut-off Treaty. Fire-eaters will argue that India should bash on regardless and stick it out as a pariah in the international system because its security is paramount.I would argue for a middle-path because we know India lacks the stamina to make it alone as China did in the 1949-1970 period. Also it would confront us with the choice of forfeiting our economic destiny.We must make do with what we have and this time we must do it well. Till now the Indian effort at weaponising its deterrent has been as fitful and lethargic as the pace of its missile programmes. Both are seriously lagging that of even Pakistan. For obvious reasons we could not weaponise the flawed thermonuclear design, but we do have a reliable fission weapon which yielded 25kT in the May 1998 test. This design could be safely boosted to a weapon of at least 50kT.A great deal of work remains to be done in the missile field. The Agni series needs to be locked down by a series of tests to prove its reliability and accuracy. The Brahmos needs to be transformed into a longer range cruise missile capable of reaching 900-1500 km. Both the weapons and the missiles should be handed over to the armed forces, though the country may still choose to keep its weapons in a dis-assembled form.

Doctrine

But first we need to alter our nuclear doctrine so that it can guide us to a different kind of force posture. The doctrine of 1998 was a slapdash job. It did not arise from Indian practice or goals, but was imposed top down to convince the world that our arsenal was purely for defence and that it would be a minimalist one, though its credibility would be assured by the fact that it was in a triad of land and sea-based and air-dropped weapons.Just how incomplete a job it was became apparent when India confronted Pakistan in the wake of the attack on Parliament in 2001 and found that our doctrine did not cover the possibility of nuclear strikes on Indian forces operating outside our national territory.The biggest hole in it was that at the time it was enunciated, India did not have the wherewithal for the massive retaliation, or to use the politically more correct term, inflict "unacceptable" destruction and punishment on the adversary, that it promised. While doctrines may precede capability, we are now confronted with the fact that we do not have the key weapon we thought we had for inflicting massive retaliation — a thermonuclear bomb.The Indian doctrine implied that since we had offered a "no first use" pledge, we would sustain a first strike by an adversary and then retaliate massively. This assumed that some of our already minimalist arsenal would also be destroyed in the adversary's strike. And so there was need for, first, measures to secure our weapons against such strikes. And, second, to have weapons that would inflict the crushing retaliation.If you take these two factors, it implied that an Indian retaliation would be of the "counter-value" type, targeting cities and population centres. These "city-busting" strikes rested on the possession of 200-300 kilotonne weapons, which cannot but be of the fusion or thermonuclear kind.

Capability

The revelations about the failure of the thermonuclear bomb means that new choices will now have to be made about our force structure since it could take 15- 20 bombs of the 25 kT variety to obtain the kind of destruction a single 200 kT thermonuclear bomb wreaks.So out goes the minimalist posture. If we are to have a credible force, we need to redo the sums about the size of the arsenal. We also need to work out different ways of deploying and using our weapons and getting our armed forces into the picture, instead of keeping them out as is the case now.Our new doctrine and re-engineered capabilities must be able to re-endorse the credibility of our retaliatory capabilities— minus the thermonuclear bomb. A "no first use" pledge could be a luxury in the present

circumstances.

What we need is a system that will provide a guarantee that a nuclear attack on India will meet with assured retaliation.
 
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http://www.hindu.com/seta/2010/06/10/stories/2010061050631600.htm

India's innovative nuclear power reactor

The reactor's development is an effort to realise futuristic objectives through innovative configuration of present-day technologies



People waiting for a nuclear renaissance expect that the new reactors on the drawing board should assure a very high level of safety and security; they must have the ability to perform with a lower level of technological infrastructure prevailing in several developing countries; they must have high fuel use efficiency and superior waste disposal options.

"The development of the Advanced Heavy Water Reactor, AHWR300-LEU, is an effort to realize these futuristic objectives through innovative configuration of present day technologies," Anil Kakodkar and Ratan Sinha, the designers of India's innovative nuclear reactor wrote in the May 2010 issue of Nuclear Engineering International.

They called the reactor India's passive breeder.

"As a result of its fuel mix and fuel breeding properties, the 300 MWe plant requires 42 per cent less mined uranium per unit of energy produced than a modern high burn up PWR", they added.

AHWR300-LEU with an estimated design life of 100 years is a vertical, pressure tube type, boiling light water-cooled, heavy water- moderated reactor with reduced environmental impact. It has many features which are likely to reduce both its capital and operating costs.

The designers have eliminated primary coolant pumps and drive motors and related control and power supply equipment, thereby saving the electric power to run them. This helps to reduce cost and to enhance reliability.

The use of heavy water at low pressure reduces the potential for leakages. The heat generated in the moderator will be recovered and used for heating the feed-water.

Quick replacement

The shop assembled-coolant channels have features which enable quick replacement of pressure tubes alone without affecting other components.

The design objective of the reactor is to require no exclusion zone beyond the plant boundary. The reactor will use natural circulation to remove heat from its core under operating and shut down conditions. In case the primary and the secondary shut down systems are not available due to the failure of all active systems or malicious employee action, passive injection of a "poison" — a high neutron absorbing liquid, in to the moderator will shut down the reactor.

When the reactor operates, its core will be very hot. Coolant removes the heat. If coolant is not available due to a Loss of Coolant Accident (LOCA), the emergency core cooling system (ECCS) will remove heat by passive means.

If the primary coolant tube ruptures, a large flow of water from accumulators will cool the reactor initially. Later, the core will be cooled by the injection of cold water from a 7000 cubic metre Gravity Driven Water Pool (GDWP) located at the top of the reactor building. After that, the passive containment cooling system (PCCS) provides long term containment cooling. GDWP serves as passive water sink giving a grace period of three days.

The reactor has a double containment with an elegant design which assists the formation of a passive water seal in the event of a loss of coolant accident. The seal isolates the reactor containment and the external environment, preventing the spread of radioactivity.

Fission of Uranium-233

The reactor fuel on an average contains 19.75 per cent of enriched uranium and the balance thorium oxide. A significant fraction of the reactor power, about 39 per cent, comes from the fission of Uranium-233 derived from in-situ conversion of thorium-232.

The reactor physics design has inherent safety characteristics during all conditions likely to be encountered during startup, shutdown and LOCA.

During an interview, Dr Sinha has stated that the scientists and engineers at BARC have designed a novel advanced heavy water reactor to burn thorium ( IEEE Spectrum, 2008)

"They say that because no reactor in the world today uses thorium on a large scale, they will be breaking new ground", he added

Currently BARC has the facility for large scale validation work.

Partly as a result of this, the reactor can achieve commercial operation by 2020.Indian scientists have been exploring various fuel cycle options for improved versions of AHWR.

AHWR300-LEU has all the safety features of AHWR. It also helps in thorium utilization.

It produces much less plutonium and minor actinides compared to Pressurized Water Reactors(PWR) which is the mainstay internationally. In view of that, this reactor is more proliferation resistant.

Since minor actinides (which have relatively long half life) are less than those in PWR, it is a better choice from considerations of waste management.

AHWR300-LEU has better reactor physics characteristics.
 
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http://www.neimagazine.com/story.asp?sectionCode=76&storyCode=2056393

India's passive breeder

India's Bhabha Atomic Research Centre has adapted its AHWR design, which features only passive safety features, to run on LEU-thorium MOX fuel. As a result of its fuel mix and fuel breeding properties, the 300MWe plant requires 42% less mined uranium per unit of energy produced than a modern high burnup PWR. By Ratan Sinha and Anil Kakodkar

The threat of climate change and the importance of sustainable development has brought nuclear power in sharper focus in recent times. Growth of nuclear power worldwide, however, requires satisfactory technological responses to the challenges of a very high level of safety and security assurance (as dictated by a very large increase in the number of reactors), ability to perform with a lower level of technological infrastructure as it prevails in several developing countries, and a high degree of fuel-use efficiency and superior waste disposal options. The development of the Advanced Heavy Water Reactor, AHWR300-LEU, is an effort to realise these futuristic objectives through innovative configuration of present day technologies.

General description

AHWR300-LEU is a 300 MWe, vertical, pressure-tube type, boiling light water-cooled, and heavy water-moderated reactor. The reactor incorporates a number of passive safety features and is associated with a fuel cycle having reduced environmental impact. AHWR300-LEU possesses several features that are likely to reduce its capital and operating costs.

"¢ Using heavy water at low pressure reduces potential for leakages

"¢ Recovery of heat generated in the moderator for feedwater heating

"¢ Elimination of major components and equipment such as primary coolant pumps and drive motors, associated control and power supply equipment and corresponding savings of electrical power required to run these pumps

"¢ Shop-assembled coolant channels, with features to enable quick replacement of pressure tube alone, without affecting other installed channel components

"¢ 100-year reactor design life

A design objective of AHWR300-LEU is to require no exclusion zone beyond the plant boundary. The AHWR300-LEU uses natural circulation for removal of heat from the reactor core under operating and shutdown conditions. All event scenarios initiating from non-availability of main pumps are, therefore, excluded. Another unique feature of its design is passive poison injection in moderator in the event of non-availability of both the primary and the secondary shut down system due to failure of all active systems, or malicious employee action.

How it works

The main heat transport (MHT) System transports heat from fuel pins to steam drum using boiling light water as the coolant. The MHT system consists of a common circular inlet header from which feeders branch out to the coolant channels in the core. The outlets from the coolant channels are connected to tailpipes carrying steam-water mixture from the individual coolant channels to four steam drums. Steam is separated from the steam-water mixture in steam drums, and is supplied to the turbine. The condensate is heated in moderator heat exchangers and feed heaters and is returned to steam drums by feed pumps. Four downcomers connect each steam drum to the inlet header.

The emergency core cooling system (ECCS) is designed to remove the core heat by passive means in case of a postulated loss of coolant accident (LOCA). In the event of a rupture in the primary coolant pressure boundary, the cooling is initially achieved by a large flow of water from accumulators. Later, cooling of the core is achieved by the injection of cold water from a 7000 m3 gravity driven water pool (GDWP) located near the top of the reactor building. After that, the passive containment cooling system (PCCS) provides long-term containment cooling following a postulated LOCA. GDWP serves as a passive heat sink yielding a grace period of three days. The core is submerged in water from GDWP long before the end of this period.

The AHWR300-LEU has a double containment with passive containment isolation. The reactor building air supply and exhaust ducts are shaped in the form of U-bends of sufficient height. In the event of LOCA, the containment pressure acts on the water pool surface and drives water, by swift establishment of siphon, into the U-bends of the ventilation ducts. Water in the U-bends acts as a seal between the containment and the external environment, providing necessary isolation between the two.

Fuel

The AHWR300-LEU fuel cluster contains 54 fuel pins arranged in three concentric circles surrounding a central displacer assembly. The Zircaloy-2 clad fuel pins in the three circles, starting from the innermost, contain 18%, 22% and 22.5% of LEUO2 (with 19.75% enriched uranium) respectively, and the balance ThO2. The average fissile content is 4.21%. The fuel also incorporates a multipurpose displacer assembly for the spraying of ECCS water directly on fuel pins during a postulated LOCA. This helps achieving negative void coefficient. The fuel is currently designed for an average burnup of 64 GWd/te. In comparison to a reference high burnup PWR considered for scenario studies under the IAEA's International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO), the AHWR300-LEU requires about 42% less mined natural uranium for the same quantity of energy produced, thus making it a favourable option for efficient utilisation of natural uranium resources. The reactor is configured to obtain a significant portion of power by fission of 233U derived from in-situ conversion from 232Th. On an average, about 39% of the power is obtained from thorium. With uranium constituting less than 22% of the total fuel inventory, the reactor produces only about 17% of the plutonium and 42% of the minor actinides as compared to the reference high burnup PWR.

The reactor physics design has inherent safety characteristics, such as negative reactivity coefficients of all conditions likely to be encountered during startup, shutdown and LOCA.

AHWR reactor systems are currently under study at the Bhabha Atomic Research Centre. Test environments include a 3MW boiling water test loop, a scaled test facility (the integral test loop) based on power-to-volume scaling for thermal hydraulic simulation of AHWRs, a natural circulation loop for stability and start-up studies, a transparent setup for natural circulation flow distribution studies, and a facility at the Apsara reactor that uses neutron radiography to perform flow pattern transition studies. Partly as a result of this large-scale validation work, the reactor can achieve commercial operation by 2020.
 

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