Energy From Thorium Discussion Forum

It is currently Dec 17, 2014 7:42 pm

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 9 posts ] 
Author Message
 Post subject: French MSR research
PostPosted: Dec 16, 2006 5:59 pm 
Offline
User avatar

Joined: Nov 30, 2006 9:18 pm
Posts: 2203
Location: Montreal
Actually, I think the nuclear share in France is closer to 80%.

More importantly though, there is some very interesting research going on in France, for example :
Quote:
http://lpsc.in2p3.fr/gpr/gpr/rsfE.htm
Parametric Studies of Molten Salt Reactors (MSR) and the Thorium Fuel Cycle
Laboratoire de Physique Subatomique et de Cosmologie
LPSC > Scientific projects > The Reactor Physics Group > Systems and scenarios

One of the co-authors of the above report, Dr. Daniel Heuer (Directeur de Recherche CNRS), was kind enough to reply to a querry I sent to their group.

I sincerely hope that they take the time to join the discussion on this forum.
I believe that we would all benefit -- Kirk is providing a truly wonderful service.


Top
 Profile  
 
 Post subject:
PostPosted: Jan 18, 2007 10:14 am 
Offline
User avatar

Joined: Nov 30, 2006 9:18 pm
Posts: 2203
Location: Montreal
Correction :
According to today's NUCLEONICS WEEK, France’s reactors "produced 428.7 terawatt-hours in 2006, 78.1% of total French power production and 89.6% of total domestic consumption" (i.e. they export quite a bit...)


Top
 Profile  
 
 Post subject:
PostPosted: Jan 18, 2007 1:18 pm 
Offline

Joined: Dec 01, 2006 12:26 pm
Posts: 11
ehh ouais ben


Last edited by Elling on May 05, 2007 5:52 am, edited 1 time in total.

Top
 Profile  
 
 Post subject: Re: French MSR research
PostPosted: Mar 15, 2007 12:29 pm 
Offline

Joined: Mar 07, 2007 11:02 am
Posts: 1062
Location: Ottawa
jaro wrote:
Actually, I think the nuclear share in France is closer to 80%.

More importantly though, there is some very interesting research going on in France, for example :
Quote:
http://lpsc.in2p3.fr/gpr/gpr/rsfE.htm
Parametric Studies of Molten Salt Reactors (MSR) and the Thorium Fuel Cycle
Laboratoire de Physique Subatomique et de Cosmologie
LPSC > Scientific projects > The Reactor Physics Group > Systems and scenarios

One of the co-authors of the above report, Dr. Daniel Heuer (Directeur de Recherche CNRS), was kind enough to reply to a querry I sent to their group.

I sincerely hope that they take the time to join the discussion on this forum.
I believe that we would all benefit -- Kirk is providing a truly wonderful service.



I have read most of their papers and in my opinion they are doing excellent work. The web page above does engage in a bit of excess criticism of the early MSR work but perhaps they felt the need to distance their work from earlier "abandoned" work.

They seem to be the first group in decades doing detailed reactor calculations while looking at changes to the base MSBR design. They do point out the serious probablem that MSBR actually did have a slight positive temperature coefficient. The early ORNL work does actually mention that this may be possible due to unknowns in the contribution graphite makes to this factor.

I have sent Kirk the pdfs I have on their work. I should check if there are some more recent publications as they seem to be drifting towards the idea of an epithermal reactor without graphite as the webpage above indicates. As Jaro mentions, hopefully we can get some of their group more involved on this site as well.


Top
 Profile  
 
 Post subject: Re: French MSR research
PostPosted: Mar 15, 2007 4:47 pm 
Offline
User avatar

Joined: Nov 30, 2006 9:18 pm
Posts: 2203
Location: Montreal
David wrote:
I have read most of their papers and in my opinion they are doing excellent work.

Thanks very much for your assessment David.

My last e-mail to the French group, back in November '06 was as follows:
Quote:
Merci beaucoup pour votre réponse.

Eh oui, vous avez bien compris la proposition: "il s'agirait de remplacer les grappes et le caloporteur présent dans les tubes de force par une circulation de sel."

J'ajouterais seulement que, évidement, toute la géométrie changerait en même temps -- soit le diamètre de tubes porte-combustible, ainsi que le "lattice pitch," pour optimiser la neutronique, et minimiser le dégagement de chaleur dans le modérateur.....

En ce qui concerne l'enrichissement isotopique du *combustible* - pour la conception du réacteur CANDU avancée (soit le CANDU "ACR" avec modérateur D2O et caloporteur H2O), on prévoie de l'uranium au ~2% U235. (Voir tableau ci-joint, ainsi que le texte "What is AECL's next-generation "Advanced CANDU Reactor (ACR)?" au http://www.nuclearfaq.ca/cnf_sectionA.htm#ngcandu )

Pour répondre à vos questions:

- le Zr présent pour isoler l'eau lourde du sel ne capture t-il pas trop (perte de régénération) ?

réponse:
Parce que les "tubes de force" ( = "Pressure Tubes" = PT) ne seront plus sous pression, comme c'est le cas présentement, avec du calo d'eau lourde, l'épaisseur du paroi peut être réduite de façon significative.
De plus, il ne serait plus nécessaire de mettre les tubes de force a l'horizontal pour accommoder les deux machines de rechargement de combustible (un de chaque coté -- voir images ci-joint).
En les mettant en vertical, on élimine d'un seul coup le charge lourd de grappes de combustible sur ces tubes (responsable du problème de « sagging » avec potentiel d’un contact éventuel avec les tubes concentriques de modérateur…. Voir image ci-joint).


- la température du sel est de 630 °C, est-ce pas trop pour avoir une isolation thermique suffisante ?

réponse:
Il n'y a pas question d'éliminer complètement le transfert de chaleur au modérateur. Il s'agit plutôt de le diminuer à un faible pourcentage de chaleur amené au modérateur par les gammas et les neutrons rapides. Ce dernier est faisable, a mon avis.


- quel est l'effet de l'eau lourde sur les coefficients de température
(coef de dilatation et modification de la thermalisation des neutrons)

réponse:
Veuillez SVP lire les textes suivants affichées par mon collègue, le physicien Dr Jeremy Whitlock, sur son site-web "Canadian Nuclear FAQ" :
1) "Why do CANDU reactors have a "positive void coefficient"? au http://www.nuclearfaq.ca/cnf_sectionD.htm#s et
2) "How do CANDU reactors meet high safety standards, despite having a "positive void coefficient"? au http://www.nuclearfaq.ca/cnf_sectionD.htm#t

Mais cet effet de l'eau lourde sur les coefficients de température sera sûrement diffèrent pour un réacteur MSR-D2O, comme vous pouvez l’imaginer, avec une géométrie totalement différente, et un enrichissement plus elevé…...

J'espère que ceci vous aidera dans les simulations pour vérifier tout ça.


Bien à vous,

Jaro Franta, Ing.


I have not had any response to this message, so I have no idea whether they have decided to do any work on the D2O-MSR.
If they have, it would likely be the first ever.

In an earlier message, there was a hint of sacrificing salt melting temperature for reduced FLiBe content in the fuel salt.
I think that's a good idea.
Besides lowering cost, it reduces upscatter of thermalized neutrons and boosts the fast-fission factor, it reduces the volume of hot material in the core (hence reducing heat transfer to the cold moderator), and the resulting higher fuel temperature improves overall energy conversion efficiency, while reducing HX size.

Whether the associated neutron kinetics would be manageable, I have no idea.

.


Top
 Profile  
 
 Post subject:
PostPosted: Jul 17, 2007 9:14 am 
Offline

Joined: Apr 11, 2007 6:17 am
Posts: 27
If you read french, a thesis about MSR :
http://lpsc.in2p3.fr/gpr/documents/theseFPerdu.pdf
(155 pages, 3.5Mb)

Another thesis (in english) :
http://www-dapnia.cea.fr/Phocea/file.ph ... 5-04-T.pdf
(141 pages, 3Mb)


Top
 Profile  
 
 Post subject: Re: French MSR research
PostPosted: Aug 02, 2008 5:15 am 
Offline
User avatar

Joined: Jun 24, 2007 10:43 am
Posts: 339
Location: Dallas, TX
I had intended to start a thread on the French Thorium Molten Salt Reactor, This link provided by Lars was my inspiration: http://hal.in2p3.fr/docs/00/13/51/49/PDF/ICAPP07_final.pdf.
The paper has an exciting title, "Optimized Transition from the Reactors of Second and Third Generations to the Thorium Molten Salt Reactor", and is authored by E. Merle-Lucotte, D. Heuer, M. Allibert, V. Ghetta, C. Le Brun, L. Mathieu*, R. Brissot, and E. Liatard.

The Abstract:
Molten salt reactors, in the configuration presented here and called Thorium Molten Salt Reactor (TMSR), are particularly well suited to fulfil the criteria chosen by the Generation IV forum, and may be operated in simplified and safe conditions in the Th/233U fuel cycle with fluoride salts. Amongst all MSR configurations in the thorium cycle, many studies
have highlighted the configurations with no moderator in the core as simple and very promising. Since 233U does not exist on earth and is not being produced today, we aim at designing a critical MSR able to burn the Plutonium and the Minor Actinides produced in the current operating reactors, and consequently to convert this Plutonium into 233U. This leads to closing the current fuel cycle thanks to TMSRs started with transuranic elements on a Thorium base, i.e. started in the Th/Pu fuel cycle, similarly to fast neutron reactors operated in the U/Pu fuel cycle. We will detail optimizations of this transition between the reactors of second and third generations to the Thorium cycle. Such a transition is based on a fleet of TMSRs with no moderator in the core, including TMSRs started with Plutonium and TMSRs directly started with 233U. We developed parametric studies to optimize these TMSRs, amongst which the study presented here, based on one of the main TMSR
parameters: the percentage of heavy nuclei in the fuel salt of the TMSR configuration, which modifies the moderation ratio of the reactor and thus influences both the initial fissile inventory and the spectrum of the reactor. We analyze the characteristics of each reactor configuration, in terms of deterministic safety parameters, fissile matter inventory, salt reprocessing, radiotoxicity and waste production, and finally deployment capacities.

Given that the French appear to have a serious LFTR development program and are doing preliminary research directed toward the development of a experimental prototype LFTR. I suspect that the French are interested in LFTR technology as an alternative to their failed LMFBR program. It would appear from the paper he French have chosen to concentrate on an unmoderated core. The French envision the TMSR as both a transuranium nuclear waste (Pu, NP, Am, Cm) burning system - the unmoderated core would give them some advantage in transuranium burning, and as a thorium fuel cycle reactor. The transuranium burners would also be thorium fuel cycle breeders.

Some interesting quotes:
Quote:
A fertile radial blanket surrounds the core. It contains a
binary fluoride salt LiF - ThF4 , with 28 mole % of 232Th.
This blanket has been designed such that it stops
approximately 80 % of the neutrons, thus protecting
external structures from irradiation while improving the
system’s breeding. The salt channel is also surrounded by
two axial reflectors. These reflectors are made of ZrC in
order to avoid the use of a moderator material.


Quote:
The general concept of the Thorium Molten Salt
Reactor (TMSR) is a 2500 MWth (1 GWe) reactor
operated in the 232Th/233U fuel cycle. In this article, TMSRs
may be started directly with 233U or with Plutonium and
minor actinides, mixed with Thorium. The reactor is
composed of a single large fuel salt channel, 1.25m radius
and 2.60m height, as shown on Fig. 1. One third of the 20
m3 of fuel salt circulates in external circuits and, as a
consequence, outside of the neutron flux.

We assume that helium bubbling in the salt circuit is able
to extract the gaseous Fission Products (FP) and the noble
metals within 30 seconds1,3.

We also consider an off-line
reprocessing of the total salt volume in a separate chemical
unit, with a complete extraction of the FPs. In this
reprocessing, the TRUs are not extracted but are reinserted
in the core to insure their self-burning in the TMSR. This
off-line reprocessing will be discussed in paragraph III.A.
We also assume that the 233U produced in the blanket is
extracted within a 6 month period.


Top
 Profile  
 
 Post subject: Re: French MSR research
PostPosted: Aug 02, 2008 7:39 am 
Offline
User avatar

Joined: Nov 30, 2006 9:18 pm
Posts: 2203
Location: Montreal
Charles Barton wrote:
I suspect that the French are interested in LFTR technology as an alternative to their failed LMFBR program.

This is like saying that Italy and Austria had a failed LWR program.
Or that ORNL had a failed MSR program.
Totally disingenuous.


Top
 Profile  
 
 Post subject: Re: French MSR research
PostPosted: Aug 02, 2008 8:39 am 
Offline

Joined: Dec 09, 2007 3:41 pm
Posts: 89
jaro wrote:

I have not had any response to this message, so I have no idea whether they have decided to do any work on the D2O-MSR.
If they have, it would likely be the first ever.

.


When I was emailing them for some advice this spring they mentioned they have a student working on a heavy water msr, but I have no clue on what has happened since. Atleast they are looking at it 8)

BTW jaro check your pm!


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group