Monju Madness!

SOURCE: David Ward ( SUBHEAD: $35 trillion and 15 years wasted are reasons to discontinue breeder reactor activity in Japan and elsewhere!

IB Publisher's note: Even though this is a long post it is a only a portion of a more detailed article. Click on link below for more.]  

By Steve from Virginia on 19 June 2011 for Economic Undertow - 

Image above: The Monju reactor, perched scenically at sea level, waiting for the next earthquake and tsunami. From the original article.

Those who think the end of the world is going to take place in 2012 may be onto something. It may be the end of the world for the nuclear power industry, which has been taking the international kicking. I am not the only one noticing!

Events — and the large numbers of plants — expose the industry to the law of averages. Despite the so-called ‘safety culture’ spin that has been promulgated in the United States and the West, nuclear plants appear to be no safer over the long term than other kinds of similarly scaled industrial ventures such as air travel or ocean liner cruising. The difference is the level of ‘process cost’ the nuke industry accepts to avoid the ‘nuisance deaths’ that accompany the better- rationalized coal electric generation- and auto industries.

A reactor will have more control rods — or redundant cooling pumps or a greater amount of concrete in the building or more pages/procedures in its operating manual — than a conventional thermal plant has equivalent safety or pollution control features. Both kinds of plants perform the same operation(s) more- or less the same way: the coal plant owns the adjacent fly- ash dump which is a leaky plastic lined pit.

The nuke is next door to its spent fuel dump – a leaky, water filled pit lined with concrete. The coal plant continuously vents its waste onto its neighbors by way of a smoke stack. The nuke saves is wastes and vomits them onto its neighbors intermittently.

Very similar (highly toxic) wastes mean quite similar outcomes. The difference is the nuke industry successfully pushes its nuisance deaths into the future, the large numbers of (older, badly sited) plants means the future is now!

The Fukushima Daiichi debacle is nowhere near the happy conclusion that TEPCO endlessly promotes. It is likely to become much worse. TEPCO’s Fabulous Filtering System intended to pull radioactive particles out of the water collecting under the facility works too well, leaving the system buzzing with dangerously radioactive sludge.

TEPCO is surprised: this is the same water radioactive enough to burn workers feet. It flows over and around ruined reactor cores, carrying whatever radioactive particles (waste) the cores emit. What is TEPCO (not) thinking?

Every day means more water pumped into reactors, more water carrying more radioactive materials outside the reactor containments with more isotopes accumulating in basements, ditches and in the aquifer under the plant. Soon enough, intensely radioactive water will overflow the basements into the ocean.

Several reactors in the US are threatened by flood waters resulting from abnormal snow pack in the Rocky Mountains along with heavy rains in the Upper Midwest. The Ft. Calhoun reactor in Nebraska is an island: it was shutdown before the flood and its core(s) are in spent fuel storage. Cooper Station is a GE boiling water reactor identical to those under siege @ Fukushima. It is also threatened by flooding, which effected the plant in 1993.

There are spent fuel lagoons at ground level at the sites which are not mentioned in media reports. There are more reactors in Louisiana and Mississippi whose operators are carefully watching the water.

There are 250+ tons of spent fuel at Ft. Calhoun, 200+ tons at Brownsville.

Flooding here, drought there: operators of France’s 44 river- side reactors are vulnerable to decreased flows due to a severe drought that has a grip on the entire north of Europe. Low water in French rivers has in the past led to shutdowns. If flows decrease sufficiently France will have real problems. Reactors need water even when shut down.

Meanwhile, here is the (stupid) drama taking place right now at the benighted Monju Fast Breeder Reactor:
Japan Strains to Fix a Reactor Damaged Before Quake
TSURUGA, Japan — Three hundred miles southwest of Fukushima, at a nuclear reactor perched on the slopes of this rustic peninsula, engineers are engaged in another precarious struggle.
Monju is 60 miles from Kyoto, a city of 1.5 million people.
The Monju prototype fast-breeder reactor — a long-troubled national project — has been in a precarious state of shutdown since a 3.3-ton device crashed into the reactor’s inner vessel, cutting off access to the plutonium and uranium fuel rods at its core.
Engineers have tried repeatedly since the accident last August to recover the device, which appears to have gotten stuck. They will make another attempt as early as next week.
But critics warn that the recovery process is fraught with dangers because the plant uses large quantities of liquid sodium, a highly flammable substance, to cool the nuclear fuel.
The Monju reactor, which forms the cornerstone of a national project by resource-poor Japan to reuse and eventually produce nuclear fuel, shows the tensions between the scale of Japan’s nuclear ambitions and the risks.
The plant, a $12 billion project, has a history of safety lapses. It was shuttered for 14 years after a devastating fire in 1995, one of Japan’s most serious nuclear accidents before this year’s crisis at the Fukushima Daiichi Nuclear Power Station. Prefecture and city officials found that the operator had tampered with video images of the fire to hide the scale of the disaster. A top manager at the plant recently committed suicide, on the day that Japan’s atomic energy agency announced that efforts to recover the device would cost almost $21.9 million. And, like several other reactors, Monju lies on an active fault.
The Monju plant is designed to ‘breed’ plutonium- reactor fuel by bombarding ordinary uranium 238 (depleted uranium) with fast neutrons from a core of medium- enriched uranium- 235 or plutonium. The heavy uranium absorbes a neutron or two and becomes plutonium- 239 or 240.

This bombarded uranium can be sent to a facility where plutonium is separated and processed into MOX fuel. So far, breeder reactors have been used to create plutonium fuel for nuclear weapons: commercial use has been problematic. Handling the plutonium in the liquid sodium- cooled/moderated breeder reactor is difficult requiring complex automated machinery.
Here is what the fracas is all about:
1. Report submitted by the Japan Atomic Energy Agency
On August 26, 2010, the in-vessel transfer machine (*) fell in the reactor vessel at the prototype fast breeder reactor Monju.
On November 9, 2010, as a result of the remote visual inspection of the inside of the in-vessel transfer machine, it was found that the gap at the top of the inner guide tube, which is normally 5-7mm in size, was actually 14.5mm.
It was therefore concluded that the in-vessel transfer machine was deformed, was no longer able to handle nuclear fuel, and could not be removed from the reactor vessel using conventional methods. (*)
In-vessel transfer machine One of components that comprise the refueling machine to transfer the reactor core elements between the reactor core and the fuel handling system during a refueling operation.

2. Effects of this event on plant safety It was confirmed that this event did not affect plant safety when the in-vessel transfer machine fell on August 26, 2010 and the current status remains unchanged.

3. Actions of NISA
The report was received by NISA in accordance with article 43-14 of “the rule for the installation, operation, etc. of nuclear power reactors in the research and development stage.”
Because this event occurred on August 26, 2010, NISA instructed JAEA to report the causes of this event and countermeasures against possible recurrences on August 27, 2010.
In addition, local nuclear safety inspectors observed the visual inspection which was carried out on November 9, 2010 and confirmed the current status of the facilities.
In future, NISA will continue to rigorously check the investigation into the cause of and corresponding countermeasures against possible recurrence of the event, as carried out by JAEA.
(Reference) Chronology of the Event Date Event
  • August 26, 2010 During the removal operation of the in-vessel transfer machine from the reactor vessel, in the machine fell inside of the reactor vessel.
  • August 27, 2010 NISA instructed JAEA to report the details of the delayed report, causes of this event and countermeasures against possible recurrence.
  • October 1, 2010 JAEA submitted the interim report to NISA.
  • October 13, 2010 During the removal operation of the in-vessel transfer machine from the reactor vessel, when the load was lifted to approximately 2 meters, an overload was detected, and the removal operation was stopped.
It is possible the in- vessel transport was damaged before it was loaded into the reactor last summer, but the damage was not noticed.

Outside of the usual proliferation/plutonium/spent fuel/radiation issues the great problem with breeders is the coolant. Because it is opaque sodium, the in- vessel refueling machine cannot be seen, only ‘implied’.

The liquid metal is an unforgiving material to work with. It is highly reactive, instantly forming oxides, burning in the presence of air, exploding when it comes into contact with water. Sodium melts @ 97.8 degrees Celsius.

It must be isolated at all times within corrosion- resistant vessels or under an inert- gas atmosphere. The equipment used to service the Monju is remote- controlled within a pressurized argon environment. This makes maintenance difficult.

Sodium or some other combination of metals with a low melting point is used as a moderator in breeders because it is more ‘transparent’ to neutrons. That is, it does not slow the neutrons emitted from the U- 235 or plutonium fuel.

A dense flux of high- energy ‘fast’ neutrons is necessary to efficiently convert U- 238 to plutonium. Both the fuel and the ‘target’ or blanket assemblies must also be placed physically close together, this requires greater heat- transfer capacity than what ordinary water provides.

The cause of the 1995 fire was the sodium- flow induced fatigue failure of a $50 part, a thermo-well sensor housing installed in a sodium cooling line.

Three tons of liquid sodium sprayed for over an hour through a hole the size of a dime and accumulated within a room next to the reactor core. Heat from the reaction and fire melted steel. Nobody bothered to shut off the air conditioning in the space which fed oxygen into the fire.

The leak was in the secondary liquid sodium circuit so no radioactive materials entered the environment but the vulnerabilities of this plant — conceived as an ‘nth- generation’ breeder plant were exposed.

The official reaction to the leak and fire was identical to the response to the ongoing calamity at Fukushima. The operator delayed releasing information about the extent of the leak and the resulting damage, instructing employees of the plant to lie to investigators.

Sodium leaks have plagued the ex-Soviet Beyolarsk fast breeder reactor. Sodium leaks and fires have been a feature of fast reactors worldwide. The combination of sodium reactivity and the stress of neutron bombardment is ‘a bridge too far’ for reactor hardware, high- strength alloys, gasket material and lubricants.

After six month’s exposure to fast neutron flux the various reactor transport machines are engaged to swap the U- 238 blanket assembles and fuel cores for ‘fresh’ replacements. The assemblies — containing 5% plutonium — are ready to be shipped to a nuclear fuel reprocessing facility so as to be refined and milled into new MOX fuel.

The Monju reactor is designed to produce 17kg of plutonium every six months. Because the plutonium can be refined to any level of enrichment, the entire process is designed to be audited/monitored by international observers including the International Atomic Energy Agency (IAEA).

The necessary fuel processing to chemically separate the plutonium from the uranium would be done at the Rokkasho Reprocessing facility. This plant is non- functional despite the staggering multi-year, multi- billion dollar investment on the part of its operator, Japan Nuclear Fuel Limited. Because of MOX/plutonium fuel hazards, completion of this plant wobbles between unlikely and uncertain. Without processing capability, the Monju plant and its output of plutonium/MOX fuel is superfluous.

Meanwhile, there are currently approximately 3,000 tons of spent fuel stored at Rokkasho. The left hand does not know or care what the right hand is doing.

Should a a fantasy world materialize out of the ruins of Fukushima where both plants are operational, large quantities of toxic plutonium fuel would be transported by sea or overland between distant parts of Japan. It’s a strange culture where putatively inexpensive baseload electricity is of greater value to ‘consumers’ than peace of mind and good health...

...The Three Stooges run a reactor: you cannot make this stuff up!...

...The breeding process is energy intensive: waste heat is directed by way of heat exchangers and a turbine set to a condenser. There are two sodium loops in series and a steam- generator where hot sodium boils water for the turbine. The electrical output is approximately 280 mw. The thermal output of the reactor is 840 mw.

A fundamental problem with this and other breeders is that the core is too small relative to its high thermal power output and neutron flux. To remove the excess heat, fast neutron reactors depend on complex and fragile heat exchangers that are vulnerable to corrosion, flow- induced fatigue and embrittlement.

The secondary heat exchanger or evaporator brings sodium and water together so as to generate steam for the turbine. The reactor is designed to operate under high water pressure. The high sodium primary temperatures thermally stress reactor components which requires elaborate engineering.

Meanwhile, the reactors under certain conditions can ‘run away’ or become ‘prompt critical’. There is little integral safety margin with this reactor such as a negative void coefficient or thermal negative feedback loops. Reactivity depends almost entirely on control rod insertion. Operators have not said — and may not know — whether control rods have been effected by the fuel transfer machine ‘problem’...

...Removing the coolant to have at the transfer machine is impossible with fuel in the reactor core. The reactor cannot be shut down because of decay heat. The fuel cannot be removed and put into fuel storage with the transfer machine in the way. This is all of a piece with the ‘You can’t get there from here’ Fukushima Follies where nothing can be done because nothing can be done.

The Monju plan is to partially dismantle the reactor lid on the ‘hot’ reactor so that the fallen machine has a larger opening through which it can be retracted. Consequently, Monju will not have an effective containment.
“The device will definitely come out this time,” said Toshikazu Takeda, director at the University of Fukui Research Institute of Nuclear Engineering, and head of a government panel that approved the latest repair plans. He said that engineers had recreated removal procedures at a lab and perfected their handling of the crane that will lift the device from the reactor vessel.
Right … ! Either that, or the reactor will blow up and contaminate 100,000 people with plutonium. Worst- case scenario is an ‘accident’ requiring the abandonment of Kyoto along with a large part of south western Japan.

The reactor business has a long way to go before it catches up with the auto industry death machine but seems intent on doing so.

A reasonable plan is to accept the failure of throwing of good money after bad. It is time to abandon the ‘digging out of a hole’ strategy. $35 trillion wasted and fifteen years of failure is a reason to discontinue breeder reactor/fuel reprocessing activity in Japan and elsewhere! It’s time for the establishment to start cutting losses while it possesses the wherewithal to do so.

See also:
Ea O Ka Aina: Time for a Cold Shutdown 6/17/11


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