On Tue, 19 Aug 2008 07:44:28 -0700 (PDT), nada 
wrote:

>On Aug 18, 7:36 pm, T. Keating  wrote:
>> On Mon, 18 Aug 2008 18:45:51 -0700 (PDT), dave.walt...@comcast.net
>> wrote:
>>
>> Snip...
>>
>> The technology claim is feasible based on many flawed premises..
>>   You're wrong on  almost every count..
>>    Hot Graphite burns when exposed to our atmosphere.  Obviously..
>>
>>    The reactor was not designed to produce electricity and was quite a
>> mess to cleanup.. (40 years after being shutdown.)   So much for
>> reprocessing the fuel in near real time.
>>
>> You claim only thermal neutron breeding.
>>      That's not going to yield a breeding ratio anywhere near
>> approaching one(1).   (which is not necessary goal for military
>> purposes.)
>>
>> Only a fast breeder is going to reach those goals.
>>
>> Therefore  you will NEVER EVER be free of the requirements for fresh
>> inputs of Pu or HEU.    Base case you've only extended the supply of
>> fuel by 30 to 40%.    Most of which will  be gone by the end of this
>> century.
>>
>> End of story..
>
>When you can find a physicist that agrees with you please do. The
>neutron splitting of thorium into Pa and Pa decay rate into U233 is
>well known. That's why YOU have no data to disprove the breeding ratio
>of a LFTR. There are 600,000 tons of high grade (50% purity) thorium
>in Idaho. Enough to power ALL of the US energy needs to 1000 years.
>Comeback again T. when you understand the subject under discussing.
>Oh, please don't forget some documentation that shows the breeding
>ration. I provided links from esblished experiments. You haven't, and
>can't.

I've seen no actual experiments claiming breeding ratios above
unity.(1.0).

Especially a molten salt based reactor, (aborbs too many neutrons).
Your entire premise is flawed. 

LFTR's are a dead end..

On Tue, 19 Aug 2008 14:02:32 -0700 (PDT), dezakin@usa.net wrote:

>
>
>T. Keating wrote:
>> On Tue, 19 Aug 2008 07:44:28 -0700 (PDT), nada 
>> wrote:
>>
>> >On Aug 18, 7:36 pm, T. Keating  wrote:
>> >> On Mon, 18 Aug 2008 18:45:51 -0700 (PDT), dave.walt...@comcast.net
>> >> wrote:
>> >>
>> >> Snip...
>> >>
>> >> The technology claim is feasible based on many flawed premises..
>> >>   You're wrong on  almost every count..
>> >>    Hot Graphite burns when exposed to our atmosphere.  Obviously..
>> >>
>> >>    The reactor was not designed to produce electricity and was quite a
>> >> mess to cleanup.. (40 years after being shutdown.)   So much for
>> >> reprocessing the fuel in near real time.
>> >>
>> >> You claim only thermal neutron breeding.
>> >>      That's not going to yield a breeding ratio anywhere near
>> >> approaching one(1).   (which is not necessary goal for military
>> >> purposes.)
>> >>
>> >> Only a fast breeder is going to reach those goals.
>> >>
>> >> Therefore  you will NEVER EVER be free of the requirements for fresh
>> >> inputs of Pu or HEU.    Base case you've only extended the supply of
>> >> fuel by 30 to 40%.    Most of which will  be gone by the end of this
>> >> century.
>> >>
>> >> End of story..
>> >
>> >When you can find a physicist that agrees with you please do. The
>> >neutron splitting of thorium into Pa and Pa decay rate into U233 is
>> >well known. That's why YOU have no data to disprove the breeding ratio
>> >of a LFTR. There are 600,000 tons of high grade (50% purity) thorium
>> >in Idaho. Enough to power ALL of the US energy needs to 1000 years.
>> >Comeback again T. when you understand the subject under discussing.
>> >Oh, please don't forget some documentation that shows the breeding
>> >ration. I provided links from esblished experiments. You haven't, and
>> >can't.
>>
>> I've seen no actual experiments claiming breeding ratios above
>> unity.(1.0).
>>
>> Especially a molten salt based reactor, (aborbs too many neutrons).
>> Your entire premise is flawed.
>
>I'm not sure where you get this idea. FLi7Be salt is very
>neutronically efficient, especially with the Be -> 2n reactions.
>Everyone for the past 40 years has come to the conclusion that a FLiBe
>salt run on the Th/U233 cycle has a breeding ratio above one.
>

FLiBE ... No such compound... doesn't exist in our universe. . 
Correct designation is  2LiF-BeF2. a mixture of two compounds. it was
used as a secondary coolant.   

The ORNL pyrolytic carbon moderated 7.4 MWt reactor was AIR cooled !!!

The fuel used in MSRE was LiF-BeF2-ZrF4-UF4(*)  (a mixture of 4
compounds.) 

(*) U233 isotope was used in UF4 mixture. 
The breeding blanket of Th232 was omitted in favor of neutron
measurements. 

Some obvious problems with the design.. 

Difficult, if not impossible to scale up GWt output levels.  Large
scale heat transfer (required for power generation) has a tendency to
separate out mixtures.  This level of cooling often results in uneven
mixtures and hot pockets. (Run-away chain reaction is a possibility.) 

Used a Th layered blanket design, which will always have inherently
LOW breeding ratio.  Lucky to achieve  0.2 breeding ratio, claims to
otherwise not substantiated.   

Claim of high burn up, contra indicated by extensive clean up
procedures needed to decommission reactor after 40 years. 

While the burn up of U233 is superior to other fuels.. This particular
experiment did not solve the U233 production problem.  Where a Pu or
HEU core provides the neutron source for breeding, resulting usual
amounts of radioactive isotopes.

----
  
The final ORNL's MSR design proposed using a fuel mixture
LiF-BeF2-ThF4-UF4  and a coolant of NaF-NaBF4,  
was NEVER BUILT nor tested !! 

http://www.answers.com/topic/molten-salt-reactor
"However, to date the molten salt reactor remains a "paper design",
that is, no molten salt reactors have been built other than the
experimental MSRE."


--- 

In Summary.. 

Only the very FOOLISH propose that  humanity stake it's ENTIRE  future
energy supply on a reactor design that's never been built, nor tested.
Even if you started today, a commercial design wouldn't be viable for
thirty, maybe forty years.    


Meanwhile .. 
  Renewables are practical today... 
  Pose no special environmental hazard. 
  Are subject of a near continuous stream of incremental improvements.
  Derives energy from a nearly inexhaustible source,  which will
likely outlast mankind and every other species on Earth.

T. Keating wrote:
> On Tue, 19 Aug 2008 07:44:28 -0700 (PDT), nada 
> wrote:
>
>> On Aug 18, 7:36 pm, T. Keating  wrote:
>>> On Mon, 18 Aug 2008 18:45:51 -0700 (PDT), dave.walt...@comcast.net
>>> wrote:
>>>
>>> Snip...
>>>
>>> The technology claim is feasible based on many flawed premises..
>>>   You're wrong on  almost every count..
>>>    Hot Graphite burns when exposed to our atmosphere.  Obviously..
>>>
>>>    The reactor was not designed to produce electricity and was
>>> quite a mess to cleanup.. (40 years after being shutdown.)   So
>>> much for reprocessing the fuel in near real time.
>>>
>>> You claim only thermal neutron breeding.
>>>      That's not going to yield a breeding ratio anywhere near
>>> approaching one(1).   (which is not necessary goal for military
>>> purposes.)
>>>
>>> Only a fast breeder is going to reach those goals.
>>>
>>> Therefore  you will NEVER EVER be free of the requirements for fresh
>>> inputs of Pu or HEU.    Base case you've only extended the supply of
>>> fuel by 30 to 40%.    Most of which will  be gone by the end of this
>>> century.
>>>
>>> End of story..
>>
>> When you can find a physicist that agrees with you please do. The
>> neutron splitting of thorium into Pa and Pa decay rate into U233 is
>> well known. That's why YOU have no data to disprove the breeding
>> ratio of a LFTR. There are 600,000 tons of high grade (50% purity)
>> thorium in Idaho. Enough to power ALL of the US energy needs to 1000
>> years. Comeback again T. when you understand the subject under
>> discussing. Oh, please don't forget some documentation that shows
>> the breeding ration. I provided links from esblished experiments.
>> You haven't, and can't.
>
> I've seen no actual experiments claiming breeding ratios above
> unity.(1.0).
>

Probably because you're head is surrounded by anti-nuclear 'sand' up to your 
neck.  Try looking.

OBTW, do you have any idea just *how hot* graphite has to get before it 
burns in air?  Thought not.

daestrom

On Tue, 19 Aug 2008 17:23:23 -0700 (PDT), dezakin@usa.net wrote:

>On Aug 19, 4:57 pm, T. Keating  wrote:
>> On Tue, 19 Aug 2008 14:02:32 -0700 (PDT), deza...@usa.net wrote:
>>
>> FLiBE ... No such compound... doesn't exist in our universe. .
>> Correct designation is  2LiF-BeF2. a mixture of two compounds. it was
>> used as a secondary coolant.  
>>
>> The ORNL pyrolytic carbon moderated 7.4 MWt reactor was AIR cooled !!!
>>
>> The fuel used in MSRE was LiF-BeF2-ZrF4-UF4(*)  (a mixture of 4
>> compounds.)
>>
>> (*) U233 isotope was used in UF4 mixture.
>> The breeding blanket of Th232 was omitted in favor of neutron
>> measurements.
>
>Congratulations on finding the wikipedia page.
>
>> Some obvious problems with the design..
>>
>> Difficult, if not impossible to scale up GWt output levels.  Large
>> scale heat transfer (required for power generation) has a tendency to
>> separate out mixtures.  This level of cooling often results in uneven
>> mixtures and hot pockets. (Run-away chain reaction is a possibility.)
>
>Do you just make this shit up? This wasn't reported by ORNL. You have
>potential problems of noble metals plating on the heat exchangers, but

 The 7.4MWt Reactor was AIR COOLED..  (Somewhat low thermal
disapation/gradiant).

There is a major issue when it comes to scaling up the design. How to
move enough coolant through the core without pressurizing?   It's
doubtful That one can cool the core @ 3GWt levels using gravity feed.
  Simple physics, I suspect that  max flow rate will top out
somewhere between ~5 to 15ft/sec.. Probably much lower..  ) 

Limiting Delta T in the core to 50C. indicates that one needs to move
~14 tonns of fuel through the core and into the heat exchanger each
second.   An even larger issue is scaling up of the heat exchangers.
Similar problems with the secondary cooling system.. 

  
>these are fission products and this poses a maintenance problem more
>than anything else. The fissonables are highly soluable in the salt.
>You dont even know what you mean by 'Run away chain reaction is a
>possibility.' Its a meaningless statement. I assume you want to say a
>criticality excursion is a possibility, but thats unsupported by the
>strongly negative temperature and void coefficients of these types of
>reactors.

Anytime you mix compounds with differing melting points and thermal
coefficients.. run through a heat exchanger a few millions of times,
it will undergo separation.   The larger delta T the more separation.

>
>> Used a Th layered blanket design, which will always have inherently
>> LOW breeding ratio.  Lucky to achieve  0.2 breeding ratio, claims to
>> otherwise not substantiated.  
>
>Now I know you dont know what you're talking about. LWRs have breeding
>ratios around .6

Bzzzt.. more like "0.3", Heavy water designs have a somewhat higher
breeding ratio but incur significant energy costs separating out
replacement D from the environment. 

>
>> Claim of high burn up, contra indicated by extensive clean up
>> procedures needed to decommission reactor after 40 years.
>
>This has nothing to do with the burn up or even the reactor. Thats
>radiolysis of the frozen salt when left unattended for years.

The experiment did NOT breed U233..   
   It was an experimental reactor that consumed U233 as a Fuel. 

>
>> While the burn up of U233 is superior to other fuels.. This particular
>> experiment did not solve the U233 production problem.  Where a Pu or
>> HEU core provides the neutron source for breeding, resulting usual
>> amounts of radioactive isotopes.
>
>And thats no worse than today, much better considering you have far
>less transuranics and those that exist can be incinerated in the
>reactor.
>
>> The final ORNL's MSR design proposed using a fuel mixture
>> LiF-BeF2-ThF4-UF4  and a coolant of NaF-NaBF4,  
>> was NEVER BUILT nor tested !!
>>
>> http://www.answers.com/topic/molten-salt-reactor
>> "However, to date the molten salt reactor remains a "paper design",
>> that is, no molten salt reactors have been built other than the
>> experimental MSRE."
>>
>> ---
>>
>> In Summary..
>>
>> Only the very FOOLISH propose that  humanity stake it's ENTIRE  future
>> energy supply on a reactor design that's never been built, nor tested.
>> Even if you started today, a commercial design wouldn't be viable for
>> thirty, maybe forty years.    
>
>And now we have the strawman...
>
>We dont need LFTR tomarrow or at all. LWRs are more than sufficient
>for several centuries. Perfecting LFTRs would be very desirable

Bzzzt.. recoverable UO2 fuel will be gone by the end of this century..

   After that.. it will cost wayyy more in energy/material
expenditures to retrieve new U235 supplies than one receives back. 
Uranium mining is a function of chemical & material transport problem.
Those inputs/energy requirements  increase significantly as the grade
of ore drops. 

>because it would make nuclear power production cheaper, more
>efficient, and safer, but its certainly not staking the future of
>humanity on a single energy supply.
>
>Now I could make a similar argument:
>
>Only the very FOOLISH propose that  humanity stake it's ENTIRE  future
>energy supply on a renewable energy regime that's never been built,
>nor tested. Even if you started today, a commercial renewable grid
>wouldn't be viable for thirty, maybe forty years.

Bullshit.. 

Known mature technology based on renewables is being deployed on a
large scale..  If the Sun ever stop's shinning the biosphere will be
toast anyway.. (no food & heat.) 

>> Meanwhile ..
>>   Renewables are practical today...
>
>In spite of wind powered Denmark having far higher electricity costs
>than nuclear powered France

The radioactive technology that France will be decommissioned in less
then a century and replaced with renewables..   

Oh.. and let's not forget that the French government operates the
public utility, meanwhile Demark uses a free market system. 

http://www.energistyrelsen.dk/sw23521.asp

Meanwhile,the French are providing massive subsidies to it's Nuclear
industry.. 

Lastly

http://www.windpower.org/composite-1971.htm
The Danes have built up it's wind turbine industry into a viable low
pollution export sector. 
 
http://www.renewableenergyworld.com/rea/news/infocus/story?id=46749
"Denmark to Increase Wind Power to 50% by 2025, Mostly Offshore"

>
>>   Pose no special environmental hazard.
>
>Tell that to the victims of banqiao dam.

A packed Soil dam built by the PLA (chinese army) using soviet
engineers designed for a 1 in 1000  yr.. flood..    then 1 in 2000yr
flood occurred in 1975 and over topped the dam.. it failed with
predictable results. 
 
Did it contaminate the SOIL for a thousand years??  NO.. 
Condemn generations of survivors to birth defects, and cancers?   NO..
How many lives did it save from yearly floods? 
   It was a Flood control project.. NOT a power generation project.. 

>
>>   Are subject of a near continuous stream of incremental improvements.
>
>Just like nuclear energy, imagine that.

Not really.. Despite massive subsidies, 
    Reactor improvements have ground to a halt..
        I.E.  Beating a dead horse !!!. 

    Physics is a harsh mistress that rarely forgives mistakes,
especially human errors and failings.   Which always seams to rear
it's ugly head when it comes to making a profit. . 

>
>>   Derives energy from a nearly inexhaustible source,  which will
>> likely outlast mankind and every other species on Earth.  - Hide quoted text -
>
>Where using the 160 trillion tonnes of fissionables would only last
>humanity 16 million years if you burn it at 1000 times our global
>energy consumption....

Bzzzzt..  Why in the world  would one propose dependency on fuel
source that requires mining all the Earth's surface?   You'll run out
of energy and materials longgggg before  you achieve your goal.. 

(P.S. Negative EROEI.. after concentrations drop below 100-200 PPM U.)