India Nuclear News And Discussion

[Theo_Fidel]

AFAIK PFBR still has a positive void coeff. Reactor depends on large coolant flow to prevent problems.

[Sanatanan]

Thanks. I have to start with Imageshack first. I wanted to post something on the In-Service Inspector . . .

You're welcome.

By sheer coincidence, I happened to access this article just this morning --After seeing your post, I thought you may like to see it (if not already done so) and so am posting the link here:

In-Service Inspection Of BWR Core Shroud At TAPS.

This article is dated 1999. I think based on this work and other similar campaigns, approvals for life extension of TAPS BWRs were obtained.

I feel this work represents a very good example of indigenous technology development. No "tech" import from US nor from France nor from Russia, was needed for this important and difficult effort, even as early as in 1999 when the thugs had ganged up against India at the NSG and were trying their best to prevent India's attempts to be self reliant in important areas of technology.

[GuruPrabhu]

Santanam,

Yes, that is an old design which has evolved significantly. Also, note that the vessels in TAPS are 304 steel. The PFBR will have D9 steel (first time in India) for wrapper tubes and 316 steel for grid plate, which is good beyond 700K (unlike 304). This is an extra safety step. The steam generator will use a modified Ferritic steel while the roof-slab will use special grade low carbon steel (A48P2).

The safety concerns have been high on the agenda. There will be in-sodium electrochemical hydrogen meters installed with ~20 ppb resolution. In addition, there will be cover gas hydrogen meters with ~30 ppm resolution. Plus, there will be oxygen meters ityadi ityadi.

The folks at IGCAR believe that despite the high Na void worth in case of a LOFA, the passive cooling system will maintain the reactor in shutdown mode even at high Na temperatures. It is everyone's choice to believe this or not.

In the debate on nuke deal, a loud section was demanding that "Uncle wants to steal FBR tech". If the tech is no good, there is nothing there to steal.

[Amber G.]

^^^ Did not know much about D9 or 316 .. would like if post some more.
(Have read up a little on my own..thanks to google and you for an interesting article
Thermal creep properties of alloy D9 stainless steel and 316 stainless steel fuel clad tubes

[GuruPrabhu]

^^^ Did not know much about D9 or 316 .. would like if post some more.

My gyaan comes from this paper, which is the most comprehensive study of FBR materials that I know of:

http://www.igcar.ernet.in/igc2004/PFBR.pdf

It has more detail than any non-expert would care to know (but it is not from a gora source, so make what you will of this.)

[Amber G.]

^^^ Thanks!

[Sanatanan]

[quote="Theo_Fidel-ji"]
. . .
There are certain scenario's in which a Sodium reactor can go out of control, options are very limited at that point. A loss of coolant actually makes the fission reaction accelerate under some scenarios.
. . .
[/quote]
And again,

[quote="he"]
AFAIK PFBR still has a positive void coeff. Reactor depends on large coolant flow to prevent problems.[/quote]

If I remember correctly, this issue was discussed in this thread (may be a few weeks back) in reponse to an article by one Swami Iyer questioning the safety of PFBR, which in turn, was based on an article by a NPA.

An authentic samadhanam for the issue may be found here (perhaps this link ws also posted at that time):

Letter to the Editor: Design Robustness and Safety Adequacy of India’s Fast Breeder Reactor

[quote]
. . .
Sodium coolant used to remove the heat from the core in a sodium-cooled fast reactor can boil once its temperature exceeds about 900◦C and produces voids. In a fast spectrum reactor, once these voids are formed at the center, they introduce positive reactivity. The fact is that such a positive void coefficient by itself is not a concern, in view of the feedback coefficients like fuel Doppler effect higher neutron absorption cross-section at higher fuel temperature) and fuel expansion coefficient, which are much stronger and act well ahead of the occurrence of significant sodium boiling, thereby keeping the power coefficient of reactivity negative at all operating and accident conditions.
. . .
[/quote]

[GuruPrabhu]

Santanam-ji,

Thanks for posting that. The effects mentioned in that excerpt were described in this link I posted above:

http://www.nuceng.ca/ep6p3/class/Module ... dJun21.pdf

Basically, Rate = N * flux * cross section

With temperature rise, there is decrease in N (due to expansion) and cross section (due to Doppler increase in absorption). So, for a constant flux, there is a decrease in fission rate, which in turn decreases the flux as well, i.e., there is a lowering of the effective eta (breeding factor) and reactivity, with temperature rise. This is not a run-away condition.

All we can do is keep posting such facts and hope that the majority of BRF readers benefit from it. The few who claim that "FBR has not much to show for it" can continue to post in that vein. No problems.

[Theo_Fidel]

Thanx for the note Sanatanan,

And here is a response to that letter which demonstrates how the DAE has over-ridden its own findings to to allow this design factor in. As you noted all this has been posted before.

http://www.princeton.edu/sgs/publicatio ... Ramana.pdf

The positive void coeff is not a major design flaw or anything, just a design factor. The question has to be is if overheating of the fuel is necessary to arrest the fission chain reaction what now cools the core esp. as the U/Pu fuel continues to produce fission heat from radioactive isotopes as at Fukushima. Circulation must be restored or core melt down will proceed even without a nuclear chain reaction. It should be noted that most of the world FBR reactors do not depend on core over-heat and Doppler effect to arrest a runaway chain reaction. i.e. designed to have -ve void coeff from the start and coolant loss will not mean reactor over heat to 900c+.

There is no way to test this restraining mechanism as you would never allow it happen to your core in normal circumstances. The only reason the DAE has done this safety 'compromise is to save money. One must mention that the cost of the reactor has doubled from design estimates. It is currently running at 12 Crore per installed MW. To have gone all the way WRT to safety would have meant even more money. Such are the problems of dealing with this 'Rakhasa'.

Also here is a interesting link to a IGCAR presentation in 2009 on PFBR construction. Many of the tools, sensors and design details are shown with detailed photographs.

http://www-pub.iaea.org/mtcd/meetings/P ... apandi.pdf

WRT the FBTR a availability of 20% can only be called underwhelming. The 2002 sodium leak caused the reactor to shut down for 6 months. And this was a tiny leak in a relatively protected area compared to what it could have been.

[GuruPrabhu]

I should have added ...

The few who claim that "FBR has not much to show for it" can continue to post in that vein.

... quoting NPA sources.

[Theo_Fidel]

Another thing to keep in mind with the PFBR is that at present it requires ~ 2 Tonnes of Pu annually, which can only come from reprocessing. Dont even ask about the costs of that, Numbers such as $20 million per tonne are mentioned. Not to count the amount of radioactive waste reprocessing produces.

Verily Nuclear power promises much, delivers little.

[GuruPrabhu]

Not to count the amount of radioactive waste reprocessing produces.

some things simply need to be corrected. Reprocessing reduces waste -- how do you figure otherwise?

Forget technical details, this does not even pass the 6 year old test.

[Theo_Fidel]

Reprocessing is not resource, material or equipment free. Hold your tongue Theo hold your tongue...

[GuruPrabhu]

^^^ Yes, I agree that reprocessing does not happen by Djinn technique -- it does need materials and equipment. However, your claim was that it *produces* waste. Please explain.

Fine, if you want to hold your tongue -- but please give your brain a free reign.

Added later: If your contention is that it "produces" low-level waste, then say so. No new radioactivity is produced -- the existing radioactive nuclei are separated into 3 categories: reprocessed MOX, high-level waste and low-level waste.

[somnath]

Total reprocessign capacity in India is 230 tons now..

the ful fledged programme will need about 2300 - 4200 tons...The Cstep paper I referenced above has the details..

http://www.cstep.in/docs/CSTEP%20Nuclear%20Report.pdf

Which is preciely why we spent so much time making sure the "clean waiver" in the nuke deal included trade in reprocessing tech....

[Sanku]

Deserves posting here


http://www.businessspectator.com.au/bs. ... ty-f-GGEFH

No limit to Tepco liability: Japan govt

TOKYO - Tokyo Electric Power should face unlimited liability for damages stemming from its crippled nuclear power plant, Chief Cabinet Secretary Yukio Edano said, indicating Japan's government will take a hard line against the utility in its rescue plan.

The cap has been one of the most contentious issues in the talks. Tepco and its creditor banks have argued for a limit on compensation, warning that without one Tepco's credit ratings could be cut to junk, making it impossible for the utility to raise funds, sources say.

"At a Diet session in 1961, a grave natural disaster of an exceptional character was explained as one beyond the imagination of humankind," Mr Edano told a parliament committee. "The (March 11) earthquake was a very large one, but it was of a scale that had been experienced by humankind in the past."

[arnab]

Deserves posting here


http://www.businessspectator.com.au/bs. ... ty-f-GGEFH

No limit to Tepco liability: Japan govt

hmm I guess that means in an Indian context NPCIL (GOI) won't be able to hide under a 'limited liability' clause. But then we already knew that.

[somnath]

hmm I guess that means in an Indian context NPCIL (GOI) won't be able to hide under a 'limited liability' clause. But then we already knew that

ACtually a bit trickier than that..India's liability law limits the overall liability for NPCIL (to 1500 crores), and specifically "excludes" natural calamities like the one we had in Fukushima..Which means, err, as GP said sometime back, if something like that happens in Kalpakkam we would be back to Indian Railway style 2 lacs for every death compensation!

[Pratyush]

^^^

At the risk of trigring a major backlash. What is wrong with the Railway compensation??

PS:- Compensation should be dependent on the earning potential along with length of productive life left in the individual. IOW, a 30 year old individual deserves more compensation in case of unnatural death then a 60 year old man in siilar circumstances.

But then I will now retreat to the kave kamplex and start dhoti shiver.

[GuruPrabhu]

^^^

At the risk of trigring a major backlash. What is wrong with the Railway compensation??

PS:- Compensation should be dependent on the earning potential along with length of productive life left in the individual. IOW, a 30 year old individual deserves more compensation in case of unnatural death then a 60 year old man in siilar circumstances.

But then I will now retreat to the kave kamplex and start dhoti shiver.

No backlash at all. Please compute the earning potential of a 30 year old who makes Rs 20k per month. What if he makes Rs 50k per month? How far does Rs 4 lakhs take his bereaved family? Rather than dhoti shaking, just do some math.

[somnath]

Praful Bidwai on nuke power..

http://www.frontlineonnet.com/stories/2 ... 009800.htm

Seems taken off almost completely from certain "nationalists" in BR!

[Amber G.]

Continued growth in uranium production

Global production of uranium increased 6% in 2010, compared with the previous year, according to the World Nuclear Association (WNA). Kazakhstan maintained its position as the leading uranium producing country.

Figures compiled by WNA show that worldwide uranium production grew from 50,772 tonnes in 2009 to 53,663 tonnes in 2010, the highest level since the early 1990s.

Kazakhstan was the largest producing country, with output of 17,803 tonnes in 2010, a 27% increase from the 14,020 tonnes it produced in 2009. Canada and Australia maintained their respective second and third places, although both their uranium outputs dropped in 2010. Canadian production dropped 4% from 10,173 tonnes in 2009 to 9783 tonnes in 2010, while Australian output fell 26% from 7982 tonnes in 2009 to 5900 tonnes.

Two African nations - Namibia and Niger - were the fourth and fifth largest uranium producers in 2010, with output of 4496 tonnes and 4198 tonnes, respectively.
<snip>

[Amber G.]

Chinese nuclear construction continues apace

The reactor building dome of unit 2 at the Yangjiang nuclear power plant in China was recently installed, 16 days ahead of schedule. Meanwhile, the second ring of the containment vessel of unit 2 at the Haiyang plant has also been lifted into place.

On the morning of 29 April, the dome - with a diameter of 37 metres, a height of 11 metres and weighing 156 tonnes - was carefully lifted by crane and placed on top of the containment vessel walls of Yangjiang unit 2. The entire operation took about 80 minutes.
<snip>

[Pratyush]

No backlash at all. Please compute the earning potential of a 30 year old who makes Rs 20k per month. What if he makes Rs 50k per month? How far does Rs 4 lakhs take his bereaved family? Rather than dhoti shaking, just do some math.

GP,

That is exacty the point that I am making. You cannot club every one together and then pay a fixed lumpsum and hope that it will be enough for that life.

[GuruPrabhu]

That is exacty the point that I am making. You cannot club every one together and then pay a fixed lumpsum and hope that it will be enough for that life.

Yes, it has been proposed here that we need a Railways Liability Bill with Rs. 1,00,00,00,00,000 in escrow against future pay-offs (it is not a question of IF but WHEN the railways will kill more citizens).

Both Supplier (including companies like GE that provide locos) and Operator (IR) should be held responsible.

In fact, India should refuse to buy locos from other countries unless they agree to $400 billion in liability.

Delhi Metro is a huge sell-off with all of these imported trains. India should develop indigenous trains instead of buying from these snake oil salesmen.

Furthermore, Railways need to demonstrate that they are safe against a 10.0 earthquake over all of India where they have tracks.

I have many more laws in mind, but you get the picture.

[Sanku]

Very compelling logic. I am not aware of the washed out lines in Sendai running a bill of 130 Billion $ for clean up. Fukushima is.

When the road meets the tire, reality is out.

[Bade]

If the number above is correct, then what are the clean up costs if new clear bums were to go off over India in a stand-off with the immediate west or northern neighbour. Each mega city taken off the screen will be hundreds of Fukushima cost for clean up. And we are willing to take 2-3 big metro hits, before counter attack. Trillions of dollars in clean up required. So why have bum onlee ? Too expensive to use for a recovery after use.

[Lalmohan]

why clean up? abandon and build new cities

[Bade]

Hiroshima and Nagasaki was not abandoned. So clean up is possible. It is more economical to clean up than build at a new site which will require more evacuation in the Indian context with high overall population.

All these costs (inflated) of course, and clean up is probably not as expensive as is being claimed.

[Lalmohan]

yes yes but in indian context starting afresh is a far better proposition for the mess most of our cities are in

[Sanatanan]

This is a brief flashback into the Fukushima Thread.

About two and a half weeks ago, there was a discussion on the status of spent fuel transport flasks and spent fuel storage facilities in India.

[quote]Got some additional {information about spent fuel rods and dry storage facilities in India} from a nice paper from Argonne National Lab's library (written by P.K. Dey, Fuel Reprocessing Division in BARC).. pretty nicely written.
. . .

- Picture of a Dry casket being moved on an open bed of a truck gave the impression of lack (IMO) of a security.. I am sure things are more secure now. (Before 9/11 it was comparatively easy to get access inside an US reactor).[/quote]
Subsequent comment said:

[quote]One picture I saw (older pic), with cask tied on the truck platform (with something like "Buri nazar ka muh kala" sign in the back of truck for extra security) did not look that secure..[/quote]
The highlighted parts of the above quotes were intriguing for me and so I did some literature survey. Based on that, I have put down my thoughts on these issues as follows.

I could access a paper titled "An Indian Perspective for Transportation and Storage of Spent Fuel". From the URL of the document I feel this also-well-written-paper by P.K. Dey, might have been presented or submitted to the IAEA. The paper has several figures and photos including one of a PHWR Spent Fuel Cask (Flask) mounted on a trailer. I have posted it here as Figure 1. The "under-slung" bed of the trailer onto which the flask has been mounted and presumably securely bolted, would tend to lower the centre of gravity of the load and hence any tendency for the flask to overturn may be reduced. The bottom lugs of the flask through which the flask might be fastened to the trailer bed can be seen in Figure 2, which presumably is an earlier version of the flask. Nevertheless, I think, some means of lashing the flask to the trailer using liberally dimensioned tie rods or appropriate steel wire-ropes in conjunction with turn-buckles might have given additional safety for the mechanical integrity of the flask on the trailer. But, looking at the photographs, it seems to me that lashing of the flask to the trailer bed has not been considered at design time since there do not seem to be any eye-bolts or other such devices near the upper end of the flask, which is where lashing / tie rod attachment might be more effective. One would need to improvise.

Of course, if the spent fuel is being transported in the public domain (as opposed to just within the boundary of the plant site, from the reactor to a co-located reprocessing plant, in which case greater control can be exercised), I can quite imagine that the tractor trailer would actually be permitted to move only during day time and that too at very slow speeds (Indian road conditions may not permit anything other than that). The consignment would most probably be moving in a convoy of vehicles, both in front and at the rear, carrying armed security personnel with wireless and other communication equipment. Appropriately qualified personnel, trained in Nuclear Radiation Measurement and Control ("Health Physics" specialists) may form an integral part of the crew accompanying the flask.

It would be interesting to see the older picture that is referred to in the quoted post, showing how the flask was lashed to the trailer.

Figure 2 (from Nuclear India Magazine, April - May 1976 issue) shows what is probably an earlier version of the PHWR Spent Fuel Flask. It has fins, presumably to help decay heat transfer to the outside atmosphere. Compared to Figure 1, the second generation flask design shown in Figure 2 does not have these fins; I conclude that it must have been found that after sufficient decay time, the heat produced by the fuel rods is low enough to eliminate the necessity of having the fins; temperature on the out side surfaces of the flask would have been found to be within acceptable limits (one of the many advantages of Nat U Fuel Rods of PHWR!). At both ends of its journey, namely at the reactor as well as at the reprocessing facility, the flask would require to be immersed in the storage pool water (which provides the required shielding) to permit loading / unloading of the spent fuel rods from the flask. Thus ease of decontamination of the external surfaces of the flask to permit its transport in public domain, might have dictated the "smooth finish" in the improved model.

Right click on thumbnails below to see larger image in New Tab or Window of the Browser
Figure 1 ..................................... Figure 2


Policies adopted for spent fuel storage, transportation and reprocessing have strong linkages. I do have some queries / doubts on these aspects, in the Indian context. Hope to revert to this at some time in the future.

[Bade]

In such an event most of the structures are already down, just need to move the contaminated debris to safe waste disposal sites to rebuild in situ anyways. Surely one cannot leave the debris alone, as water and wind will pollute larger areas outside immediate impact centers if not disposed of properly. So clean up is essential and those costs remain even if one moves to another location to rebuild whole cities.

yes yes but in indian context starting afresh is a far better proposition for the mess most of our cities are in

[GuruPrabhu]

Very compelling logic. I am not aware of the washed out lines in Sendai running a bill of 130 Billion $ for clean up. Fukushima is.

The trains killed people. The reactors didn't. Is human life more important or residual radioactivity?

[Sanku]

If the number above is correct, then what are the clean up costs if new clear bums were to go off over India in a stand-off with the immediate west or northern neighbour. Each mega city taken off the screen will be hundreds of Fukushima cost for clean up. And we are willing to take 2-3 big metro hits, before counter attack. Trillions of dollars in clean up required. So why have bum onlee ? Too expensive to use for a recovery after use.

That is not a valid comparison for various reasons, I mention two obvious ones.
1) We are not talking of dismantling the current nuclear system. The discussion on liabilities arises in the post 123 world.
2) A commercial activity and a act of war are certainly not comparable.

Let us please not dilute the discussion by bringing in items such as comparison to railways et al. This merely leads to the conclusion that nuclear power can be supported only by very thin arguments, which is not really the case. There can be a valid case for NPPs when handled properly with all the issues duly handled.

Since this is BRF a lot goes, if statements like Nuclear sector == railway was made in any real world serious discussion, it would be quite disaster.

[Sanku]

Thanks Sanatanan Saar, a really helpful and knowledge post. Many thanks.

[GuruPrabhu]

The comparison to railways is causing problems, so rather than do the comparison, some folks are busy saying it is "invalid". The last excuse was that a person had a choice not to take a train.

I can not think of a more valid comparison -- nuke power and railways are both public utilities run by GOI. One kills people, other doesn't. Hence, the focus on the one that doesn't kill people is inexplicable.

[abhischekcc]

Nationalists on BR??!!!?!??!

Who woulda thunk it?

[Sanku]

The comparison to railways is causing problems, so rather than do the comparison, some folks are busy saying it is "invalid". The last excuse was that a person had a choice not to take a train.

The comparison with Delhi Jal Board and AEC now please?

I can not think of a more valid comparison -- nuke power and railways are both public utilities run by GOI. One kills people, other doesn't. Hence, the focus on the one that doesn't kill people is inexplicable.

They are both Govt utilities, one kills people, the other does not.

Let this thread be to discuss E Coli in DJB water now.

[Theo_Fidel]

Sanku,

Don't forget ICF Chennai explosion. Also Solar PV 'explosion' causing 1000 times the contamination.

out

[GuruPrabhu]

Let this thread be to discuss E Coli in DJB water now.

Brilliant suggestion!

Babudom works based on precedence. If a Babu is asked to look at liability of GOI in terms of compensation, said Babu will look around and say, "Oh, DJB killed folks due to negligence and didn't pay anything, so Chalta Hai onlee."

Why is nuke being singled out because of irrational fears of the invisible?

GOI can not work on irrationalities. It needs solid laws based on the existing norms in the country. The current norms are a massive Chalta Hai, or occasionally a puny "Take Rs 4 lakhs and go to hell".