ALARA STUDIES FOR EDF NUCLEAR POWER PLANTS. 2008 ISOE conference H. BERTIN EDF-UTO 2 Presentation draft 1. EDF and UTO presentation 2. From PANTHER-RP.

ALARA STUDIES FOR

EDF NUCLEAR POWER

PLANTS

H. BERTIN EDF-UTO2 2008 ISOE conference

Presentation draftPresentation draft

1. EDF and UTO presentation

2. From PANTHER-RP simulation tool to practical recommendations

3. The example of in-site recommendations implementation

4. Gain issued from the methodology implementation

1. A brief presentation of EDF Group and UTO

H. BERTIN EDF-UTO4 2008 ISOE conference

A brief presentation of the EDF GroupA brief presentation of the EDF Group

The EDF Group a leading player in the European energy industry.

EDF Group is present in all areas of the electricity value chain, from generation to trading, and active in the gas chain in Europe.

Leader in the French electricity market, the Group also has solid positions in the United Kingdom, Germany and Italy.

Breakdown of EDF Group's generation worlwide *

RE: Renewable Energies

Installed capacity

H. BERTIN EDF-UTO5 2008 ISOE conference

UTO: a Nuclear Technical Support UnitUTO: a Nuclear Technical Support Unit

In charge of Fleet Maintenance

for EDF NPP’s

(Nuclear Power Plants)

2. From PANTHER-RP simulation to practical recommandations

H. BERTIN EDF-UTO7 2008 ISOE conference

PANTHER-RP models and calculationsPANTHER-RP models and calculations

PANTHER-RP Model

Source workstation

Plans et iso = 3D models

Dose rates calculation for each source and for each workstation

Biological Protection

Autres9%

By-Pass de témpérature

3%

LAP3%

RIS BP3%

RIS MP33%

BF38%

LSE 20%

Radiological context

Dose rate reduction coefficient calculation for each option

spectrometry data, radiological map = radiological model

Maintenance programm = Workstations, task duration

Biological protection list = Workstations, task duration

H. BERTIN EDF-UTO8 2008 ISOE conference

An UTO recommandation exampleAn UTO recommandation example

5-

shielding definition

• BOUCLE 1 – Local R412 – RCP120VP–Radiological protection option

•

•

RCP120VP

12 mm lead shield in front of hot branch

Lead matress

12 mm lead shield

Lead matress aound RCP 120 valve

3. An implementation example

H. BERTIN EDF-UTO10

2008 ISOE conference

TRICASTIN exampleTRICASTIN example

The NPP has identified UTO recommendations in the logistic activities management

H. BERTIN EDF-UTO11

2008 ISOE conference

TRICASTIN exampleTRICASTIN example

UTO recommendations are also integrated in the shielding contractor documents

RCP 120 VP valve

Lead Screen

gratting

Hot Branch

Lead matress

4. Gains

H. BERTIN EDF-UTO13

2008 ISOE conference

Gains : the integrated doseGains : the integrated dose

In 2006 : radiological gains around 25 H.mSv issued from UTO recommendation implementation compared to implementation based on habits

An optimised shielding implementation : the methodology developed helps NPP in choosing the best ALARA radiation protection options.

Global dose decrease for a similar outage

Global outage dose

664,82

613,617

580

600

620

640

660

680

2005(VP) 2007(VP)

Year

Do

se

(H

mS

v)

TR1

Shielding contractor dose decrease

Shielding contractor dose

17,63

7,05

0

5

10

15

20

2005(VP) 2007(VP)

Year

Do

se (

Hm

Sv)

TR1

H. BERTIN EDF-UTO14

2008 ISOE conference

This progress, based on TRICASTIN example, is due to:This progress, based on TRICASTIN example, is due to:

More biological protections

Mechanical stress calculations

Contributing sources identification

Justification of the lead mattresses’ thickness from 6 mm to 12 mm

Optimal scenario definition

H. BERTIN EDF-UTO15

2008 ISOE conference

New biological protection  

Permanent shielding support

H. BERTIN EDF-UTO16

2008 ISOE conference

ConclusionConclusion

These elements leads to encouraging collective integrated dose decrease compared to the historical and empirical approaches that were previously implemented on-site.

A prototype tool, that will help NPPs to analyse the optimal shielding protection implementation scenario, will be tested in 2 years on a real outage in Tricastin in 2010.