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PostPosted: Nov 12, 2008 2:44 am 
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Not only it takes years to develop mines but there is quite often local opposition. It is there in Australia, the country (really a sparsely populated continent) with maximum reserves. They have so far refused to sell it to India. There is much more disturbance due to any change in land use in densely populated India, resulting in resistance. Even a car plant had to be relocated in India due to local opposition in spite of additional jobs it could create. Uranium mining carries with it the stigma of radioactivity. Less the ground you disturb, better it is. I know it sounds like Green propoganda but that is the real basis for its acceptance. You cant really count on uranium in seawater to power the world. It is really best to use U238 and thorium after breeding some fissile material to start fast reactors.
A million tons of depleted uranium and spent fuel is lying round the world.


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PostPosted: Nov 12, 2008 3:48 am 
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I mean i am surprised that people/companies owning the plants did not plan ahead to get enough fuel secured, as they must be loosing tons of money by not running the plants they have...

Agreed that it does not make sense to extract uranium from the oceans without the favorite B and R words.


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PostPosted: Nov 12, 2008 6:50 am 
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jagdish wrote:
You cant really count on uranium in seawater to power the world. It is really best to use U238 and thorium after breeding some fissile material to start fast reactors.


I can only come to the conclusion that you are completely uninformed about the resource base of Uranium. We wont ever recover uranium from the sea simply because the hard rock resources will allways be so plentiful that it will be wasteful to do so. Breeder reactors are a dead end as long as they carry any capital premium at all.


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PostPosted: Nov 12, 2008 6:54 am 
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dezakin wrote:
I can only come to the conclusion that you are completely uninformed about the resource base of Uranium. We wont ever recover uranium from the sea simply because the hard rock resources will allways be so plentiful that it will be wasteful to do so. Breeder reactors are a dead end as long as they carry any capital premium at all.


If it is so, then why is half Indian capacity down because of the lack of fuel?


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PostPosted: Nov 12, 2008 12:13 pm 
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ondrejch wrote:
dezakin wrote:
I can only come to the conclusion that you are completely uninformed about the resource base of Uranium. We wont ever recover uranium from the sea simply because the hard rock resources will allways be so plentiful that it will be wasteful to do so. Breeder reactors are a dead end as long as they carry any capital premium at all.


If it is so, then why is half Indian capacity down because of the lack of fuel?

Because the Indian government placed emphasis on breeding rather than mining. Not terribly surprising when you have crooks and clowns like Lalu as representative Indian politicians. I think I've repeated this several times.


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PostPosted: Nov 12, 2008 12:50 pm 
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dezakin wrote:
We wont ever recover uranium from the sea simply because the hard rock resources will allways be so plentiful that it will be wasteful to do so.

Wasteful of what ? ...tidal flow ?

Quote:
Nuclear India, VOL. 40/NO.1-2/Jul.-Aug. 2006
Recovery of Uranium from Seawater by Harnessing Tidal Energy
A K Saxena
PICUS, Desalination Division Bhabha Atomic Research Centre, Mumbai
In the last century uranium has universally gained acceptance as primary energy source. Currently it caters to about 16% of the electricity generation globally. Uranium was projected as the main workhorse of future when the fossil energy reserves dwindle by the middle of this century.
The terrestrial distribution of uranium ore occurrence is grossly uneven.
With a large coastline, India, Japan, Korea and a few other nations have a larger stake in exploiting the 4.5 billion tones of uranium locked in seawater. The greatest of the scientific and technological challenges in extracting uranium from seawater are lying in finding a technology that gives a net positive energy balance in terms of electricity produced from the so recovered uranium and the other is the cost of production.
This article deals with the Indian efforts on both these issues.
Basic adsorption mechanism
During seventies and eighties the Initial investigations on the possibilities of recovery of uranium from seawater were done using inorganic adsorbents. The inorganic adsorbents suffer limitations of adsorption rate and insufficient mechanical stability. Since early nineties extensive investigations are being carried out on organic adsorbents. Poly Acrylamid Oxime (PAO) was picked up as the best bet for studies since July 1999. It preferentially extracts heavy metal ions by chelating mechanism. A polypropylene fibre substrate is irradiated with electron beam to create grafting sites on the polymer chain and then treated with acrylonitrile to graft cyano groups on those sites. Then the cyano groups are reacted with hydroxylamine to convert them into amidoxime groups.
These amidoxime groups trap the loosely bonded uranyl ion from the uranyl tricarbonate present in the ionic form i.e. UO2 (CO3)3 in seawater. For each pair of two molecules of PAO one uranium atom is captured. Stoichiometrically PAO should have an extraction capability of 3.6 kg U/kg PAO.
Lab-scale experiments
During lab-scale experiments, many types of fiber cross-sections and geometries were evaluated for establishing efficacy of grafting. Polypropylene fibre of 1.5 Denier cross-sections as stem material in nonwoven felt form was used. Electron Beam Radiation induced grafting of acrylonitrile was carried out with optimized parameters. The solution viscosity and temperature were also found to be important factors. Then the cyno group was converted to PAO.
The substrate was then reacted with alkaline solution to impart hydrophylicity and adsorption characteristics. The tokens of size 75x70x2 mm thick and 150x150x2mm thick were used.
Corrosion, bio fouling and their combined effect on the adsorption kinetics and mechanical properties of the materials used in the suspension assembly and the substrate were studied and their compatibilities with seawater and process chemicals were established.
Based on initial success of extracting about 800 micro-g of uranium by harnessing the tidal wave using PAO adsorbent, a process flow sheet for a facility to extract 100gU/year was developed.
Conclusion
The specially developed organic adsorbent PAO has shown promising results for recovery of uranium from seawater. Pumped circulation schemes are inherently riddled with negative electricity gain, which means that the electricity producing potential of the recovered uranium is less than the electricity spent in its recovery. Harnessing tidal waves has the advantage of positive electricity gain. The extent of energy gain ratio will depend much on the site selection. Feasibility studies on various sizes of pilot scales will help in optimization of process design parameters of adsorbent synthesis and improving the yield of recovered uranium. Various configurations of contactor array designs are being developed to facilitate the operational flexibility for the offshore unit of the plant and utilization of tidal energy/waves more efficiently.


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PostPosted: Nov 12, 2008 12:57 pm 
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dezakin wrote:
Because the Indian government placed emphasis on breeding rather than mining.

OTOH.....

Quote:
Uranium shortage hits Nuclear Power
Some of the uranium mining projects have been hampered due to delay in getting environmental clearances and also on account of the difficult terrain in which the mines are located
Mumbai, May 20 2008

Shortage of uranium and a shut-down at four plants dragged down revenues and profit of Nuclear Power Corporation of India Ltd for the fiscal ended March 2008.

The corporation's net profit for the year dipped by 31 per cent to Rs 1,078 crore, from Rs 1,570 crore the previous year.

Income from operations declined by 7 per cent, to Rs 3,333 crore from Rs 3,592 crore.

Mr S Thakur, Executive Director (Corporate Planning), said that due to insufficient uranium supply, power production for the year fell to about 16,960 MU (million units) in 2007-08 from 18,000 MU the previous year.

Shutdown of plants

The lack of uranium supply was compounded by the shut-down of Narora-I, Kaiga-III, Rajasthan-II and Madras-I plants. These 220 MW plants are under going technical upgradation, said Mr. Thakur.

The average plant load factor has decreased to 60 per cent from 90 per cent achieved last year. The 220 MW plants are now running at 150 to 160 MW so as to optimally use the fuel (uranium), he said.

He said that some of the uranium mining projects have been hampered due to delay in getting environmental clearances and also on account of the difficult terrain in which the mines are located. A new uranium mill, which was to go online, has also been delayed, Mr Thakur said.


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PostPosted: Nov 12, 2008 1:14 pm 
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dezakin wrote:
Rossing shows that you can do this even with low grade hard rock ores.


Some interesting background.....
Quote:
WNA Weekly Digest (16 December 2005)
Rössing mine to continue.
After three years study and deliberation Rio Tinto has decided that US$112 million will be invested in extending the life of the Rössing uranium mine in Namibia to 2016 and returning its annual output to 4000 t U3O8. Half the expenditure will be on new mine equipment and half on the mill refurbishment.
Rossing 13/12/05.

Quote:
NuclearFuel DECEMBER 5, 2005
Rio Tinto may soon decide on Rossing’s future
A Rio Tinto investment committee is scheduled to meet
Dec. 13 in London to discuss the future of its 68.6%-owned
Rossing Uranium Ltd. mine in Namibia. Most market analysts
expect Rio Tinto to give the go-ahead for an expansion
to keep the mine operating to 2017. But such an expansion
would occur in an area where substantially more overburden
would need to be removed to recover uranium using openpit
mining techniques.
If the expansion decision were nega-tive,
Rossing has said it expects to close its operations
around 2009.

Quote:
Rising Interest in Nuclear Power Brings New Life to Uranium Mining;
Firm's Boom Helps Namibian Town, Worries Environmentalists

Washington Post, 6 December 2006
Craig Timberg, Washington Post Foreign Service

This sandy little company town, with its tree-lined streets and concrete homes set amid a vast, forbidding desert, had all the signs of terminal decline just a few years back. Both banks closed. The only gas station shut off its pumps. And employable young men, realizing the bleak future of the giant uranium mine that gave Arandis life, began drifting away.

But something unexpected happened on the way to the funeral for Arandis: The nuclear industry, stagnant for two decades, reversed its fortunes at a time of rising oil prices and growing realization that burning fossil fuel caused global climate change. Nuclear went from being seen as a dirty source of energy to a comparatively clean, efficient one.

From that shift in perception, mainly in the minds of Westerners thousands of miles away, the fate of this remote African town went from doom to boom.

"The future was very dark," said the energetic mayor of Arandis, Daniel Muhuura, who like hundreds of residents here has spent his entire professional life working for Roessing Uranium Mine. "Now the future is very bright."

Dramatic turnarounds have happened across the continent as a quest for mineral riches, similar to the one that helped fuel the 19th century's "Scramble for Africa," has become a hot economic story of the decade. Decisions in boardrooms around the world have sent prices soaring for copper in Zambia, coltan in Congo and oil in Angola, Nigeria and Sudan.

From rising demand for these commodities, sub-Saharan Africa's economic growth has hit rates not seen in three decades.

Perhaps no renaissance, however, has matched that of the uranium industry's.

Roessing Uranium Mine opened in 1976 during nuclear power's heyday. But the Three Mile Island accident in 1979 and Chernobyl in 1986 caused a profound political backlash that nearly halted new reactor construction. Uncertainty about how to handle the dangerous radioactive waste created by nuclear power plants also contributed to its unpopularity.

By 2001, the price for uranium oxide had fallen to about $7 a pound, one-sixth of its peak. Two years later, facing massive losses, Roessing announced plans to close.

Under that plan, the mine was to cease operations in 2007 after having dug 1 billion tons of rock
out of a jagged, bleached landscape often compared to the surface of the moon. Instead, oil prices soared and global warming became the stuff of newspaper headlines and Hollywood movies. Interest in building new nuclear reactors grew, and the price of uranium oxide rose to $62.50 a pound.

Roessing, which recently made its first delivery to an increasingly energy-hungry China, has decided to continue mining until at least 2016, mine officials say.

They expect to end this year with Roessing's first substantial profit, and tax bill to the Namibian government, in five years.

And the mine, whose workforce dropped from 3,800 in the 1970s to 860 last year, has begun hiring again.

"It is definitely a dramatic change," said company spokesman Rehabeam Hoveka. "It is good news for Arandis. It is good news for Namibia, too."

A second uranium mine, meanwhile, is slated to open nearby soon. Three others within 60 miles are in various stages of development. So where Arandis was once going to be a mining town without a mine, soon there could be five in the area.

The boom in uranium mining has caused grumbling from the tourism industry, which fears the loss of pristine landscapes, and environmentalists, who fear damage to the fragile biodiversity of the Namib, regarded as the driest and oldest desert in the world. Some environmentalists also are concerned about the renewed growth of an industry they still regard as dangerous despite industry claims of safety improvements since the Chernobyl disaster.

"They cannot tell us that they are safer than before," said Bertchen Kohrs, head of Earthlife Namibia, speaking from Windhoek, the capital. "It starts here with mining uranium, the whole cycle starts. Who says that some day we won't have to take back the nuclear waste here in Namibia?"

Roessing mine is a massive, dun-colored canyon two miles long, nearly a mile wide and more than 1,000 feet deep. From its lip, the giant dump trucks that haul uranium ore from the mine floor look like children's toys.

Several crushing machines pulverize the rock into sand, then powerful acids extract the traces of uranium. The end product, after processing, is a fine gray powder that leaves the mine in steel drums weighing 900 pounds. Mine officials say each holds as much potential energy as 40,000 barrels of oil.

All of Roessing's uranium oxide is used by civilian reactors, mine officials say, and is exported only to countries approved by the International Atomic Energy Agency.

The government of Iran owns 15 percent of Roessing, a legacy of early investment in the 1960s by the shah there. Mine officials say no shipment of uranium has ever been made to Iran, and the country has no right to the mine's product. Roessing's majority owner is Rio Tinto, a global mining conglomerate.

Officials in Arandis say they hope to use the unexpected revival of the mine to secure the future of their town, which already has, by African standards, an enviable infrastructure, including paved roads, a soccer stadium, a library, streetlights and steady sources of electricity and clean water. Two small clothing factories and a technical college provide some jobs not directly affiliated with the mine.

The banks have not resumed operations, but one recently opened a cash machine in Arandis, and work on a new gas station is to begin this month, said Muhuura, the mayor. With population on the rise again, the town recently made a deal with a builder to construct 50 homes.

The mine also has donated one of its dump trucks to Arandis, where it sits massively, with giant rubber wheels twice the height of most men, in the center of town. It is the first piece of what town officials hope is an eventual mining museum, part of the plan to help the town survive the next big downturn in uranium demand, whenever it comes.

"We want to turn around to show the world that this town will never be a ghost town," Muhuura said.

Quote:
Mine Closure Warning Amid Uranium Price Concerns
Source: Rössing Uranium Limited / WNA / Cameco / ESA
Editor: Daniel MacIsaac
2004 January 10

Namibia's Rössing Uranium Limited has announced that unless there is a significant improvement in the company's financial fortunes this year, it expects to close down its Rössing uranium mine by 2007.

Rössing's business services manager, Rehabeam Hoveka, said in a statement issued last month: "With the current uranium price, high costs and the continued strengthening of the US dollar/Rand exchange rate, the Rössing uranium mine is running at a growing loss this year.

"The current plans are to mine out the present pit, which will be towards the end of 2007, after which the mine would close its operations."

Rössing said it has completed studies on a proposed Phase 2 extension of the existing open-pit mine. An environmental impact assessment indicates that the Phase 2 extension would prolong the life of the mine to 2015, produce approximately USD 500 million worth of uranium, employ 930 people annually and continue to make a significant contribution to the Namibian economy. Rössing's uranium production represented 2.5% of total GDP in Namibia in 2001 and 10% of the country's exports that year.

Figures compiled by the London-based World Nuclear Association (WNA) show that Rössing, part of the Rio Tinto group, produced 2333 tU or 6.5% of global uranium output in 2002, placing Namibia sixth among uranium-producing countries.

Rössing said, however, that the current combination of uranium prices, the continued rise of the Rand against the US dollar (USD) and production costs need "to improve significantly before a Phase 2 extension is possible". Indeed, business services manager Hoveka warned the mine may need to consider closing down even earlier than 2007.

At the same time, however, he stressed everything possible was being done to stabilise the mining operation, including "looking for support from current and potential new customers".

WNA analyst Steve Kidd told NucNet this week that while existing unfavourable market conditions were well understood, Rössing's announcement still came as "a bit of a shock" for the industry - and one whose "reverberations have not yet sunk in".

Mr Kidd said market trends and conditions at Rössing lie at the heart of the company's current troubles. He said that while uranium prices have been strengthening (to approximately USD 14.50 / pound by the end of 2003), most long-term supply contracts - negotiated in the devalued dollar - have failed to reflect the increased value. Mr Kidd added that, on the other hand, a general delay in the development of new nuclear-power projects has made clients wary of entering into long-term agreements in the first place. Instead, many have opted to buy uranium through short-term, "spot market"-style deals, promoting instability among suppliers like Rössing in the process.

Mr Kidd said for other uranium suppliers to make up the shortfall represented by a 2007 Rössing closure, they would require encouragement and "an adjustment in the market".

He said: "Suppliers would say they're happy to make up the difference, but that they need the price incentive to do it. But that can't happen overnight; and the situation is already bound up with tight supply in any case."

Mr Kidd said customers would probably have to accept agreements for longer-term supply contracts of between five and 10 years' duration. He added: "Those kinds of contracts have not been happening over the past years, so we have mines closing down rather than opening."

Meanwhile, Canada's Cameco Corporation, the world's largest supplier of uranium, released its own position paper on the impact of uranium prices on 9th January.

Cameco said "some of the recent and unexpected market developments" led it to review the impact of spot-price increases on its sales-contract portfolio. Cameco said it "feels it is prudent to remind investors that many of the company's contracts were signed years ago when spot prices were much lower. Consequently, the contracts have pricing terms which will limit the benefit of further spot prices increases in 2004."

While Cameco pointed out that it has benefited from spot price increases in 2003 (which saw an increase of more than 45%), it has also had to limit the length of contracts to retain "as much upside pricing potential as possible - while ensuring adequate cash flow with a mix of market-related and fixed-price contracts".

Cameco said it has more than 100 million pounds of uranium committed over the next five years. It said its committed sales, which declined rapidly over this period, will be replaced with contracts reflecting the current, significantly-improved market outlook.

Cameco president and chief executive Jerry Grandey said: "Future uranium prices must reflect the risks taken and returns required by producers to bring on new mines that will be needed in the coming years to provide secure supply to nuclear utility customers."

Cameco expects its uranium sales volumes to total approximately 32 million pounds this year.

The Euratom Supply Agency's (ESA) annual report for 2002 warned: "Known world reserves of uranium are more than enough to cover the requirements of existing reactors and are likely to continue to increase as exploration progresses but, as it takes many years from exploration to actual production, it cannot be excluded that there will be periods of instability with shortages of uranium and sudden price increases."
The ESA added that present levels of uranium would not be increased "until producers see an adequate price and return on their investment".
The briefing paper 'Environmental Assessment Impact on the Proposed Mine Life Extension of Rössing Uranium Limited' is available on the company's website (http://www.rossing.com).


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PostPosted: Nov 12, 2008 3:21 pm 
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dezakin wrote:
Because the Indian government placed emphasis on breeding rather than mining. Not terribly surprising when you have crooks and clowns like Lalu as representative Indian politicians. I think I've repeated this several times.


I saw a presentation from an Indian peace researcher like that at a conference, but in a more scientific way...

The unfortunate thing about India is the close connection between the civil and military fuel cycle. Therefore the use of the fuel is limited such that weapons grade to fuel grade plutonium is produced. Of course this results in higher fuel requirements.

But the big problem I had with this theory is that with all the Pu stock they have, why not reuse as MOX?

PS. What's wrong with breeders? The Indians have a really nice one, named the AHWR. Very advanced Pu to U-233 converter and a Th-U breeder. But well nice quality U-233 too...It's like a combination of a BWR and CANDU.

_________________
Liking All Nuclear Systems, But Looking At Them Through Dark And Critical Glasses.


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PostPosted: Nov 12, 2008 5:03 pm 
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STG wrote:
But the big problem I had with this theory is that with all the Pu stock they have, why not reuse as MOX?


IIRC the issue was that Indians did not have facilities suitable for MOX fuel fabrication (remote robotic facilities needed, which are not needed for WG Pu machining...), were unable to import them due to embargo, and now they are getting some after the US-Indian deal.


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PostPosted: Nov 12, 2008 8:57 pm 
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jaro wrote:
dezakin wrote:
We wont ever recover uranium from the sea simply because the hard rock resources will allways be so plentiful that it will be wasteful to do so.

Wasteful of what ? ...tidal flow ?

Of course not. Wasteful of capital that would be better invested in hard rock mines that return far more uranium per dollar invested, even at very low ore grades. Seawater uranium recovery is an interesting technology that will never be used because uranium will allways be too cheap for it to be worthwhile.


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PostPosted: Nov 12, 2008 9:07 pm 
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STG wrote:
PS. What's wrong with breeders? The Indians have a really nice one, named the AHWR. Very advanced Pu to U-233 converter and a Th-U breeder. But well nice quality U-233 too...It's like a combination of a BWR and CANDU.


Breeders often have a capital premium on them that makes the entire cycle worthless at any uranium price we care to imagine in the next several centuries. Even without a capital premium, solid fuel breeders are uneconomic because of fuel reprocessing and fabrication expenses. It doesnt begin to break even until uranium hits $800/kg, over ten times todays price.

And this is why I place so much emphasis on the LFTR, because no other breeder regime has any hope of closing the fuel cycle.


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PostPosted: Nov 14, 2008 10:51 am 
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Proposed AHWR design is not a breeder. It is a mix of CANDU and PWR (NOT BWR). It shall also use thorium fuel, with U233 and with reactor grade Plutonium as fissile components, It is expected to recover U233 used but Plutonium shall have to be fed. It shall be dependent on fast breeders reactors for fissile material. I only hope that LFTR, if and when constructed, shall require fissile feed only at srart. We may find out, inspite of all the calculations, that it requires additional feed from time to time. We must try out these things while we have sufficient plutonium recoverable from spent LWR fuel. Only Russians have the resources and are working on it. Indians are only making a valient try. They may even succeed if they get access to plutonium from reprocessing imported fuel.
Breeding in fast reactors and recovery of fissile material for re-use are the steps which can material-wise sustain nuclear power. Otherwise the subject of this discussion shall ring true in a few decades for the world, as it has been locally for India. Perhaps we should try replacement of sodium coolant in fast reactors with liquid salts including fluorides. Spherical fuel like in PBMR may also help to cut costs. A fast PBMR with metallic fuel and salt coolant is likely to be the shape of things to come. Any surplus fissile matter shall help thorium fuel supplements till fast thorium reactors are introduced.
Electro-refining of metallic fuel (like copper refining but remotely handled) may turn out to be most economic reprocessing.


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PostPosted: Nov 14, 2008 11:46 am 
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jagdish wrote:
Proposed AHWR design is not a breeder. It is a mix of CANDU and PWR (NOT BWR).

To the contrary: from the illustrations & quote below, you can see that it is a combination of CANDU and BWR, with flow from the reactor pressure tubes going directly to the steam drum.
Note in particular the caption on the "REACTOR BLOCK COMPONENTS" diagram, indicating "TO STEAM DRUM" and "FROM STEAM DRUM".
Quote:
The Primary Heat Transport (PHT) System is designed to cool fuel assemblies by boiling light water, which flow through the coolant channels by natural circulation.
During normal reactor operation, full reactor power is removed by natural circulation caused by thermosyphoning phenomenon. Primary circulation pumps are eliminated and the necessary flow rate is achieved by locating the steam drums at a suitable height above the center of the core, taking advantage of the reactor building height.
The steam-water mixture from each coolant channel is led through 125 mm NB tail pipes to four steam drums, which are located with an elevation difference of 39 m with respect to inlet feeder (coolant channel bottom). The steam at a pressure of 70 kg/cm2 is separated from the steam-water mixture in steam drums.
The steam is led to turbine by two 400 mm NB pipes. The steam from the turbine is condensed and after purification of the condensate and preheating, it is pumped back to the steam drums at a temperature of 165°C. The feed water is mixed with the water separated from steam-water mixture at 285°C in the steam drums. The water level in the steam drum is a function of reactor power and is maintained at a set level during power operation.
Orifices are provided at the entry to the coolant channels to improve the thermal hydraulic stability, and are sized to yield nearly uniform exit quality of steam in all the channels.

Gentilly-1, a prototype-scale CANDU-BWR was built & operated in Quebec during the 1970's. The reactor had a +ve reactivity coefficient, due to the use of NU. India's AHWR should fix that problem by using a slightly higher fissile content (ie. Pu from FBRs).


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PostPosted: Nov 14, 2008 9:36 pm 
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jagdish wrote:
Breeding in fast reactors and recovery of fissile material for re-use are the steps which can material-wise sustain nuclear power. Otherwise the subject of this discussion shall ring true in a few decades for the world, as it has been locally for India.


You're being willfully ignorant here. There is no uranium shortage now or for the next ten thousand years. Uranium follows a log normal distribution and costs less than 50/kg to produce from ore grades as poor as 200/ppm. If India is running into problems in uranium extraction, thats a problem exclusive to Indias incompetant ineffectual government and bribe based economy still under the license raj, not of resources.

http://nuclearinfo.net/Nuclearpower/WebHomeAvailabilityOfUsableUranium
http://nuclearinfo.net/Nuclearpower/UraniuamDistribution

Uranium resources have never been a significant cost component of nuclear power and never will. That India has a uranium shortage only means that India is incompetant.


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